| 1. |
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| 2. |
- Fridén, Jan, et al.
(författare)
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Adaptive Response in Human Skeletal Muscle Subjected to Prolonged Eccentric Training
- 1983
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Ingår i: International Journal of Sports Medicine. - 0172-4622 .- 1439-3964. ; :4, s. 177-183
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Tidskriftsartikel (refereegranskat)abstract
- The peripheral adaptation process associated with repeating eccentric training over a longer period of time was studied in m. vastus lateralis of eleven healthy males aged 24 +/- 4 years. The maximal dynamic concentric muscle strength was only slightly improved after 8 weeks of training. However, eccentric work capacity was dramatically increased (375%). A maximal eccentric stint immediately after fulfilled 8 weeks of training caused a selective glycogen depletion from the type 28 fibers. An increased number of type 2C fibers was observed. The ultrastructure analysis showed an essentially well-preserved fine structure. Volume density of mitochondria was somewhat higher in all fiber types after training. Z-band widths were not affected by eccentric training. It is concluded that skeletal musculature adapts itself in a functional manner to the extreme tension demands put on them. Improved coordination and reorganization of the contractile apparatus of muscle fibers are the determining mechanisms of this adaptation.
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| 3. |
- Fridén, Jan, et al.
(författare)
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Implementation of periodic acid-thiosemicarbazide-silver proteinate staining for ultrastructural assessment of muscle glycogen utilization during exercise
- 1985
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Ingår i: Cell and Tissue Research. - 0302-766X .- 1432-0878. ; :242, s. 229-232
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Tidskriftsartikel (refereegranskat)abstract
- Distribution of glycogen particles in semithin and ultrathin sections of biopsy samples from human muscles subjected to either short- or long-term running were investigated using PAS and Periodic Acid-ThioSemiCarbazide-Silver Proteinate (PA-TSC-SP) staining methods. Glycogen particles were predominantly found immediately under the sarcolemma or aligned along the myofibrillar I-band. After long-term exhaustive exercise type-1 fibers with a few or no glycogen particles in the core of the fibers were frequently observed. The subsarcolemmal glycogen stores of these "depleted" type-1 fibers were about three times as large as after exhaustive short-time exercise. Another indication of utilization of subsarcolemmal glycogen stores during anaerobic exercise was that many particles displayed a pale, rudimentary shape. This observation suggests fragmental metabolization of glycogen. Thus, depending on type of exercise and type of fiber differential and sequential glycogen utilization patterns can be observed
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| 4. |
- Fridén, Jan, et al.
(författare)
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Sublethal muscle fibre injuries after high-tension anaerobic exercise
- 1988
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Ingår i: European Journal of Applied Physiology and Occupational Physiology. - 0301-5548 .- 1432-1025. ; :57, s. 360-368
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Tidskriftsartikel (refereegranskat)abstract
- The vastus lateralis muscles of eleven male elite sprinters (17-28 years) were investigated in order to examine the impact of high tension anaerobic muscular work on muscle fibre fine structure. In an attempt to reproduce the training regimen six subjects ran 20 repetitions of 25 s on a treadmill with 2 min 35 s in between, at a speed corresponding to 86% of their personal best 200 m time. PAS-stained sections of biopsies taken approximately 2 h after training generally indicated glycogen depletion in type 1 and type 2B fibres. At the light microscopic level, no signs of inflammation or fibre rupture were observed. However, at the ultrastructural level, frequent abnormalities of the contractile material and the cytoplasmic organelles were detected. Z-band streaming, autophagic vacuoles and abnormal mitochondria were the most conspicuous observations. Control specimens from sprinters who did not perform the acute exercise routine also displayed structural deviations, although to a lesser degree. It is hypothesized that during sprint training the leg musculature is put under great mechanical and metabolic stress which causes the degenerative response reported here.
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| 5. |
- Fridén, Jan, et al.
(författare)
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Topographical localization of muscle glycogen: an ultrahistochemical study in the human vastus lateralis
- 1989
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Ingår i: Acta Physiologica Scandinavica. - 0001-6772 .- 1365-201X. ; 135, s. 381-391
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Tidskriftsartikel (refereegranskat)abstract
- The fine structural pattern of glycogen storage in resting and sprint-exercised human vastus lateralis muscle fibres of different types was analysed using ultrahistochemical methods. Three male subjects (31-36 years) performed 60 consecutive, supramaximal bouts of bicycle exercise, each starting every 1 min and having a duration of 8 s (including approximately 3 s of acceleration). The load was estimated to correspond to 200% of VO2-max. Five other subjects (22-27 years) constituted controls. Ultrathin sections stained with periodic acid-thiosemicarbazide-silver proteinate (PA-TSC-SP) clearly revealed a compartmental distribution of glycogen. Glycogen is stored at five topographically, and probably also functionally, different locations. They are the subsarcolemmal, intermyofibrillar, para-Z-disc, N2-line, and H-zone spaces. During the exercise, glycogen from the N2-line and para-Z-disc locations is preferentially utilized. Serial sections stained with uranyl acetate and lead citrate demonstrated that glycogen stores of the type 2 fibres were more depleted than those of type 1 fibres. The implications of the differential intracellular glycogen storage are discussed
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| 6. |
- Abrams, G. D., et al.
(författare)
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Pronator teres is an appropriate donor muscle for restoration of wrist and thumb extension
- 2005
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Ingår i: J Hand Surg [Am]. ; 30:5, s. 1068-73
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To compare the detailed architectural properties of the pronator teres (PT), extensor carpi radialis brevis (ECRB), and extensor pollicis longus (EPL) muscles to evaluate the suitability of PT-to-ECRB and PT-to-EPL surgical procedures. METHODS: Muscle physiologic cross-sectional areas and region-specific muscle fiber lengths were measured in cadaveric PT, ECRB, and EPL muscles (n = 10 muscles of each type). One-way repeated-analyses of variance measures and post hoc t tests with Bonferroni corrections were used for statistical comparisons. RESULTS: The ulnar head of the PT was present in 8 of 10 specimens. The average PT fiber length was similar to that of the ECRB (7.02 +/- 0.49 cm vs 6.17 +/- 0.27 cm) but was significantly longer than that of the EPL (5.44 +/- 0.25 mm). Fiber length in the humeral head of the PT was longer compared with the ulnar head (7.19 +/- 0.52 cm vs 4.14 +/- 0.25 cm). The average physiologic cross-sectional area of the PT was similar to that of the ECRB (3.5 +/- 0.4 cm2 vs 3.3 +/- 0.3 cm2) but was significantly larger than that of the EPL (3.5 +/- 0.4 cm2 vs 1.1 +/- 0.1 cm2). CONCLUSIONS: From an architectural point of view the PT is an excellent donor choice for transfer to the ECRB for restoration of wrist extension or to the EPL for restoration of thumb extension. Because there is fiber length heterogeneity within the PT, however, when the ulnar head is present it may limit the total excursion of the donor muscle. These data suggest that releasing the ulnar head of the PT before transfer may result in larger excursions of this important motor in tendon transfer surgery.
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| 7. |
- Amrutkar, Manoj, et al.
(författare)
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Genetic Disruption of Protein Kinase STK25 Ameliorates Metabolic Defects in a Diet-Induced Type 2 Diabetes Model
- 2015
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 64:8, s. 2791-2804
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the molecular networks controlling ectopic lipid deposition, glucose tolerance, and insulin sensitivity is essential to identifying new pharmacological approaches to treat type 2 diabetes. We recently identified serine/threonine protein kinase 25 (STK25) as a negative regulator of glucose and insulin homeostasis based on observations in myoblasts with acute depletion of STK25 and in STK25-overexpressing transgenic mice. Here, we challenged Stk25 knockout mice and wild-type littermates with a high-fat diet and showed that STK25 deficiency suppressed development of hyperglycemia and hyperinsulinemia, improved systemic glucose tolerance, reduced hepatic gluconeogenesis, and increased insulin sensitivity. Stk25(-/-) mice were protected from diet-induced liver steatosis accompanied by decreased protein levels of acetyl-CoA carboxylase, a key regulator of both lipid oxidation and synthesis. Lipid accumulation in Stk25(-/-) skeletal muscle was reduced, and expression of enzymes controlling the muscle oxidative capacity (Cpt1, Acox1, Cs, Cycs, Ucp3) and glucose metabolism (Glut1, Glut4, Hk2) was increased. These data are consistent with our previous study of STK25 knockdown in myoblasts and reciprocal to the metabolic phenotype of Stk25 transgenic mice, reinforcing the validity of the results. The findings suggest that STK25 deficiency protects against the metabolic consequences of chronic exposure to dietary lipids and highlight the potential of STK25 antagonists for the treatment of type 2 diabetes.
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| 8. |
- Anderson, K. D., et al.
(författare)
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Acceptable benefits and risks associated with surgically improving arm function in individuals living with cervical spinal cord injury
- 2009
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Ingår i: Spinal Cord. - 1362-4393. ; 47:4, s. 334-8
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Tidskriftsartikel (refereegranskat)abstract
- STUDY DESIGN: Secure, web-based survey. OBJECTIVES: To determine how quadriplegics in the US view tendon transfer surgeries (TTS) and what activities of daily living (ADL) involving arm/hand function are important in improving quality of life (QoL). SETTING: World wide web. METHODS: Individuals >or=18 years of age living with a cervical spinal cord injury (SCI). Participants obtained a pass code to enter a secure website and answered survey questions. A total of 137 participants completed the survey. RESULTS: Two-thirds of participants had injury levels between C4/5 and C5/6. Over 90% felt that improving their arm/hand function would improve their QoL. ADL that were ranked most important to regain were dressing, feeding, transferring in/out of bed, and handwriting. Less than half of the participants had never been told about TTS and only 9% had ever had TTS. Nearly 80% reported that they would be willing to spend 2-3 months being less independent, while recovering from surgery, to ultimately become more independent. Over 75% reported that the ideal time preferred to have TTS, if chosen, would be within 5 years post-injury. CONCLUSION: Regaining arm and hand function is of primary importance to individuals with cervical SCI, in particular, to increase independence in multiple ADL. There is a critical need in the US to improve awareness of TTS as a viable option for improving arm/hand function in some people. This information needs to be provided early after injury so that informed choices can be made within the first 5 years.
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| 9. |
- Andersson, Jonny K, 1972, et al.
(författare)
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Cost description of clinical examination and MRI in wrist ligament injuries
- 2018
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Ingår i: Journal of Plastic Surgery and Hand Surgery. - : Medical Journals Sweden AB. - 2000-656X .- 2000-6764. ; 52:1, s. 30-36
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The total number and cost of wrist MRIs in the catchment area of the Vastra Gotaland Region in Sweden (population 1 723 000) during 1 year was analysed, together with the number and content of referrals. Methods: Six radiology departments reported the numbers and rate of all MRI investigations intended to diagnose wrist ligament injuries (n=411) and other injuries to the wrist. Results: The additional cost of the difference between MRIs and a clinical examination by a hand surgeon, plus indirect costs for patients with suspected wrist ligament injuries, was calculated as 957 000 euros. Conclusions: It is recommended that MRI should only be used in patients in whom there are clinical difficulties in terms of diagnosing wrist ligament injuries. It is suggested that patients with suspected wrist ligament injuries should be referred directly to an experienced hand surgeon, capable of performing a standardised wrist examination and, when needed, diagnostic arthroscopy and final treatment. The proposed algorithm for the diagnosis and treatment of suspected wrist ligament injuries presented in the present study could save time for the patient and for the radiology departments, as well as reducing costs. The ability to implement the early and appropriate treatment of acute ligament injuries could be improved at the same time.
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| 10. |
- Andersson, Jonny K, 1972, et al.
(författare)
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Distal radio-ulnar joint instability in children and adolescents after wrist trauma.
- 2014
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Ingår i: Journal of Hand Surgery, European Volume. - : SAGE Publications. - 1753-1934 .- 2043-6289. ; 39:6, s. 653-661
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Tidskriftsartikel (refereegranskat)abstract
- This study retrospectively evaluated the medical records and radiographs of patients younger than aged 25 that were referred for a second opinion due to ulnar-sided wrist pain and persistent distal radio-ulnar (DRU) joint instability. We identified 85 patients with a major wrist trauma before the age of 18. Median age at trauma was 14 years. Median time between trauma and diagnosis of DRUJ instability was 3 years. Sixty-seven patients (79%) had sustained a fracture at the initial trauma. The two most common skeletal injuries related to the DRUJ instability were Salter-Harris type II fractures (24%) and distal radius fractures (19%). In 19 patients (22%), the secondary DRUJ instability was caused by malunion or growth arrest. Eighteen patients (21%) had no fracture; in spite of this, they presented with subsequent symptomatic DRUJ instability. Fourteen of these 18 patients had a triangular fibrocartilage complex (TFCC) tear, confirmed by arthroscopy, open surgery, or magnetic resonance imaging. In conclusion, late DRUJ instability due to wrist fractures or isolated TFCC tears was found to be common in children and adolescents.Level of evidence: IV.
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| 11. |
- Andersson, Jonny K, 1972, et al.
(författare)
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Efficacy of Magnetic Resonance Imaging and Clinical Tests in Diagnostics of Wrist Ligament Injuries: A Systematic Review.
- 2015
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Ingår i: Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association. - : Elsevier BV. - 1526-3231. ; 31:10
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Tidskriftsartikel (refereegranskat)abstract
- To investigate the diagnostic performance of magnetic resonance imaging (MRI) and clinical provocative tests on injuries to the triangular fibrocartilage complex (TFCC), the scapholunate (SL) ligament, and the lunotriquetral (LT) ligament.
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| 12. |
- Andersson, Jonny K, 1972, et al.
(författare)
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Patients With Triangular Fibrocartilage Complex Injuries and Distal Radioulnar Joint Instability Gain Improved Forearm Peak Pronation and Supination Torque After Reinsertion.
- 2020
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Ingår i: Hand (N.Y). - : SAGE Publications. - 1558-9455 .- 1558-9447. ; 15:2, s. 281-286
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Tidskriftsartikel (refereegranskat)abstract
- Forearm peak pronation and supination torque measurements are reduced up to 30% in patients with triangular fibrocartilage complex (TFCC) 1B injuries with concomitant distal radioulnar joint (DRUJ) instability. The aim of our study was to evaluate whether patients with TFCC 1B injuries, with concomitant DRUJ instability, improve in forearm peak pronation and supination torque following TFCC reinsertion surgery where postoperative DRUJ stability was achieved.We report a retrospective case series with short-term follow-up (20 months) of the postoperative forearm peak torque in pronation and supination in 11 patients (9 women/2 men, average age at surgery 32 years) operated on by TFCC reinsertion. Two of the initial 13 patients were later on reoperated due to recurring DRUJ instability and were therefore excluded in this follow-up study. Nine were treated by arthroscopic TFCC reinsertion and 2 by open technique. The forearm peak pronation and supination torque were measured pre- and postoperatively and compared with the uninjured side.On average, a 16% improvement of the forearm peak torque was achieved in the injured wrist, as well as clinically assessed DRUJ stability. Functional postoperative improvement was noted in all patients, with reduced pain, good satisfaction, and acceptance of the surgery and the final result.We conclude that patients with TFCC injuries and DRUJ instability gain improved forearm peak pronation and supination torque after reinsertion. We also conclude that forearm peak pronation and supination torque is a valuable tool in the preoperative diagnostics of TFCC injuries with DRUJ instability as well as in the postoperative follow-up.
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| 13. |
- Andersson, Jonny K, 1972, et al.
(författare)
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Patients with triangular fibrocartilage complex injuries and distal radioulnar joint instability have reduced rotational torque in the forearm.
- 2016
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Ingår i: The Journal of hand surgery, European volume. - : SAGE Publications. - 2043-6289. ; 41:7, s. 732-8
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Tidskriftsartikel (refereegranskat)abstract
- A total of 20 patients scheduled for wrist arthroscopy, all with clinical signs of rupture to the triangular fibrocartilage complex and distal radioulnar joint instability, were tested pre-operatively by an independent observer for strength of forearm rotation. During surgery, the intra-articular pathology was documented by photography and also subsequently individually analysed by another independent hand surgeon. Arthroscopy revealed a type 1-B injury to the triangular fibrocartilage complex in 18 of 20 patients. Inter-rater reliability between the operating surgeon and the independent reviewer showed absolute agreement in all but one patient (95%) in terms of the injury to the triangular fibrocartilage complex and its classification. The average pre-operative torque strength was 71% of the strength of the non-injured contralateral side in pronation and supination. Distal radioulnar joint instability with an arthroscopically verified injury to the triangular fibrocartilage complex is associated with a significant loss of both pronation and supination torque.
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| 14. |
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| 15. |
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| 16. |
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| 17. |
- Berglund, Maria, 1975-
(författare)
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Biomolecular Aspects of Flexor Tendon Healing
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Flexor tendon injuries in zone II of the hand (i.e. between the distal volar crease and the distal interphalangeal joint) can be costly for both the afflicted individual and society because of the high cost of a long rehabilitation period, complicated by tendon ruptures or scarring with adhesion formation, causing impaired range of motion. The aim of the present thesis was to characterize more fully the deep flexor tendon, the tendon sheath and their response to injury in a rabbit model in order to find potential targets to improve the outcome of repair. The intrasynovial rabbit deep flexor tendon differed from the extrasynovial peroneus tendon in the expression of collagens and transforming growth factor-β1 gene expression. Differences were also found in collagen III and proteoglycans between regions of the flexor tendon subjected to either compressive or tensile load. After laceration and subsequent repair of the flexor tendon, a shift in collagen gene expression from type I to type III occurred. Proteoglycans were generally increased with the notable exception of decorin, a potential inhibitor of the profibrotic transforming growth factor-β1 which was markedly increased during the first two weeks after repair in tendon tissue but remained unaltered in the sheaths. Both vascular endothelial growth factor and basic fibroblast growth factor mRNA levels remained essentially unaltered, whereas insulin-like growth factor-1 increased later in the healing process, suggesting potential beneficial effects of exogenous addition, increasing tendon strength through stimulating tenocyte proliferation and collagen synthesis. Matrix metalloproteinase-13 mRNA levels increased and remained high in both tendon and sheath, whereas there was only a transient increase of matrix metalloproteinase-3 mRNA in tendon. We could also demonstrate a significant increase of the proportion of myofibroblasts, mast cells and neuropeptide containing nerve fibers in the healing tendon tissue, all components of the profibrotic myofibroblast-mast cell-neuropeptide pathway.
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| 18. |
- Bersch, Ines, et al.
(författare)
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Electrical stimulation-a mapping system for hand dysfunction in tetraplegia
- 2018
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Ingår i: Spinal Cord. - : Springer Science and Business Media LLC. - 1362-4393 .- 1476-5624. ; 56:5, s. 516-522
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Tidskriftsartikel (refereegranskat)abstract
- Study design Retrospective data analysis Objectives To define the distribution of the motor points and excitability of the key wrist and finger actuators in order to detect upper (UMN) and lower motor neuron (LMN) lesions potentially influencing the development of a tenodesis grasp. Setting A rehabilitation centre for spinal cord injuries, Nottwil, Switzerland. Methods Forearm muscles of 32 patients with tetraplegia (AIS A-D) were tested bilaterally with electrical stimulation (ES) to differentiate whether UMN or LMN was present. For testing, a standardised mapping was developed. All patients underwent the same positioning schedule. Results Sixteen hands developed a tenodesis grasps, 24 hands showed neither shortening nor tightening of the finger flexors. Two patients developed unilateral tenodesis grasp and showed no tightening of the finger flexors on the contralateral hand. Seven patients developed tenodesis grasps symmetrically and bilaterally, whereas one maintained an essentially open hand without tightening of the finger flexors. All hands that developed a tenodesis grasp showed a LMN lesion of the M. extensor digitorum communis (EDC). The frequency of the tenodesis grasp differed significantly between the groups with and without intact reflex arc (p < 0.0001). Conclusion Surface ES may serve as a diagnostic tool to detect an UMN or LMN lesion of the key actuator muscles affecting the tenodesis grasp. These findings provide information that is essential for the choice of treatment to optimise function of the tetraplegic hand.
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| 19. |
- Bersch, Ines, et al.
(författare)
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Motor Point Topography of Fundamental Grip Actuators in Tetraplegia: Implications in Nerve Transfer Surgery
- 2020
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Ingår i: Journal of Neurotrauma. - : Mary Ann Liebert Inc. - 0897-7151 .- 1557-9042. ; 37:3, s. 441-447
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Tidskriftsartikel (refereegranskat)abstract
- The differentiation between an upper motoneuron (UMN) lesion and lower motoneuron (LMN) lesion of forearm muscles in patients with tetraplegia is critical for the choice of treatment strategy. Specifically, the M. pronator teres (PT), M. flexor digitorum profundus III (FDPIII), and M. flexor pollicis longus (FPL) were studied since they represent key targets in nerve transfer surgery to restore grasp function. Forearm muscles of 24 patients with tetraplegia were tested bilaterally with electrical stimulation (ES) to determine whether UMN or LMN lesion was present. For detecting and testing the nerve stimulation points, a standardized mapping was developed and clinically applied. The relationship between the anatomical segmental spinal innervation and the innervation pattern tested by ES was determined. The data of 44 arms were analyzed. For PT, 19 arms showed an intact UMN, 18 arms an UMN lesion, and seven arms partial denervation. For FDPIII, three arms demonstrated an intact UMN, 26 arms an UMN lesion, 10 arms partial denervation, and five arms denervation. For FPL, two arms presented an intact UMN, 16 arms an UMN lesion, 12 arms partial denervation, and 14 arms denervation. A total of 20.1% ES tested muscles were partially denervated. In four patients, only one arm could be tested because of surgery-related limitations. According to the level of lesion and the segmental spinal innervation, most denervated muscles were present in the patient group C6 to C8. The ES, together with the developed mapping system, is reliable and can be recommended for standardized testing in surgery and rehabilitation. It offers the possibility to detect if and to what extent UMN and LMN lesions are present for the target muscles. It allows for refined pre-operative diagnostics and prognostics in spinal cord injury neurotization surgery.
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| 20. |
- Bersch, I., et al.
(författare)
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Role of Functional Electrical Stimulation in Tetraplegia Hand Surgery
- 2016
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Ingår i: Archives of Physical Medicine and Rehabilitation. - : Elsevier BV. - 0003-9993. ; 97:6
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Tidskriftsartikel (refereegranskat)abstract
- The use of functional electrical stimulation (FES) to improve upper limb function is an established method in the rehabilitation of persons with tetraplegia after spinal cord injury. Surgical reconstruction is another well-established yet underused technique to improve the performance of the upper extremities. Hand surgery plays an essential role in restoring hand function, mobility, and quality of life in the tetraplegic population. The knowledge about the effects of FES on a structural and functional level is fundamental for understanding how and when FES can be used best to support the effect of hand surgery, both pre- and postoperatively. In this article we discuss principles of FES and how FES improves functional outcome after surgical reconstruction. The reported results are based on preliminary clinical observations. (C) 2016 by the American Congress of Rehabilitation Medicine
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| 21. |
- Bersch, Ines, et al.
(författare)
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Upper and lower motor neuron lesions in tetraplegia: implications for surgical nerve transfer to restore hand function.
- 2020
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Ingår i: Journal of applied physiology. - : American Physiological Society. - 1522-1601 .- 8750-7587. ; 129:5, s. 1214-1219
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Tidskriftsartikel (refereegranskat)abstract
- Nerve transfers (neurotizations) performed under optimal conditions can restore some voluntary control in muscles of the upper extremities in patients with tetraplegia. However, the type of motoneuron lesions in target muscles for nerve transfers influences the functional outcome. Using standardized maps of motor point topography, surface electrical stimulation reliably defines the kind and extent of motoneuron lesion in the sel,ected muscles. In a muscle with an intact lower motor motoneuron, nerve transfers can often successfully reinnervate the chosen key muscle. Conversely, in a lower motoneuron lesion, the nerve transfer outcome is less predictable. However, direct muscle stimulation appears to ameliorate the morphological precondition, a finding that necessitates new preoperative approaches to optimize reinnervation in denervated/partially denervated muscles. Therefore, understanding the impact of electrical stimulation in diagnostics, prognostics, and treatments of upper limbs in tetraplegia is critical for neurotization procedures.
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| 22. |
- Biering-Sørensen, F, et al.
(författare)
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International Spinal Cord Injury Upper Extremity Basic Data Set.
- 2014
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Ingår i: Spinal cord. - : Springer Science and Business Media LLC. - 1476-5624 .- 1362-4393. ; 52:9, s. 652-657
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Tidskriftsartikel (refereegranskat)abstract
- Objective:To develop an International Spinal Cord Injury (SCI) Upper Extremity Basic Data Set as part of the International SCI Data Sets, which facilitates consistent collection and reporting of basic upper extremity findings in the SCI population.Setting:International.Methods:A first draft of a SCI Upper Extremity Data Set was developed by an international working group. This was reviewed by many different organisations, societies and individuals over several months. A final version was created.Variables:The final version of the International SCI Upper Extremity Data Set contains variables related to basic hand-upper extremity function, use of assistive devices, SCI-related complications to upper extremity function and upper extremity/hand reconstructive surgery. Instructions for data collection and the data collection form are freely available on the ISCoS website (www.iscos.org.uk).Conclusion:The International SCI Upper Extremity Basic Data Set will facilitate consistent collection and reporting of basic upper extremity findings in the SCI population.
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| 23. |
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| 24. |
- Bjerkefors, Anna
(författare)
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Performance and trainability in paraplegics : motor function, shoulder muscle strength and sitting balance before and after kayak ergometer training
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Spinal cord injury (SCI) results in a complete or partial loss of motor and/or sensory function below the injury level. An SCI causes extensive functional impairment compelling many persons to wheelchair usage. Maintaining an adequate strength and control of trunk and shoulder muscles becomes essential, as the majority of every day tasks will be performed in a sitting position. Moreover, physical exercise is crucial to avoid risks connected with a sedentary life-style. Therefore, it becomes important to find suitable, effective, and attractive physical activities to retain and even improve motor functions achieved during rehabilitation. Ideally, such a training activity should be versatile and have the potential to improve several capacities beneficial to everyday life and thereby increase the independence of persons with SCI. Kayak paddling appears to fulfil several of the criteria for such an activity. Objectives: The overall aims were to see if, and to what extent, a period of training on a modified kayak ergometer could influence functional performance as well as specific qualities, such as, shoulder muscle strength and sitting balance control in a group of postrehabilitated persons with thoracic SCI. An additional aim was to understand more about the availability of the trunk muscles in a person with a clinically complete thoracic SCI and how the trunk muscles are used to maintain upright sitting in response to balance perturbations. Methods: Ten adult post-rehabilitated persons with thoracic SCI performed 30 sessions of kayak ergometer training for a 10-week period, with progressively increased intensity and balance demand in the medio-lateral direction. Pre- and post-training measurements included performance in functional wheelchair tests, maximal voluntary shoulder muscle strength, and trunk stability in response to support-surface translations. Electromyographic (EMG) recordings from deep and superficial trunk muscles were obtained in a sub-sample of two subjects, one with a high thoracic SCI and one able-bodied person. Results: There were significant improvements with training in functional performance, shoulder muscle strength, and the ability to maintain an upright sitting posture in response to balance perturbations in the group of persons with SCI. The EMG results revealed that the person with a high thoracic SCI, clinically classified as complete, was still able to activate trunk muscles below the injury, both in maximal voluntary efforts and in response to balance perturbations, but the response pattern differed from that of the ablebodied. Conclusions: The improvements in test-performance observed with the kayak ergometer training in the persons with SCI should enhance their capacity to master similar challenges in everyday life, which, in turn, might lead to a greater independence. The pilot data on muscle activation highlight the importance of including examination of trunk muscle function in persons with thoracic SCI in relation to injury classification, prognosis, and training prescription.
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| 25. |
- Brown, Stephen H. M., et al.
(författare)
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Mechanical strength of the side-to-side versus Pulvertaft weave tendon repair
- 2010
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Ingår i: The Journal of Hand Surgery. - : Elsevier BV. - 1531-6564 .- 0363-5023. ; 35:4, s. 540-545
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The side-to-side (SS) tendon suture technique was designed to function as a repair that permits immediate postoperative activation and mobilization of a transferred muscle. This study was designed to test the strength and stiffness of the SS technique against a variation of the Pulvertaft (PT) repair technique. METHODS: Flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) tendons were harvested from 4 fresh cadavers and used as a model system. Seven SS and 6 PT repairs were performed, using the FDS as the donor and the FDP as the recipient tendon. For SS repairs, the FDS was woven through one incision in the FDP and was joined with 4 cross-stitch running sutures down both sides and one double-loop suture at each tendon free end. For PT repairs, the FDS was woven through 3 incisions in the FDP and joined with a double-loop suture at both ends of the overlap and 4 evenly spaced mattress sutures between the ends. Tendon repairs were placed in a tensile testing machine, preconditioned, and tested to failure. RESULTS: There were no statistically significant differences in cross-sectional area (p = .99) or initial length (p = .93) between SS and PT repairs. Therefore, all comparisons between methods were made using measures of loads and deformations, rather than stresses and strains. All failures occurred in the repair region, rather than at the clamps. However, failure mechanisms were different between the 2 techniques-PT repairs failed by the suture knots either slipping or pulling through the tendon material, followed by the FDS tendon pulling through the FDP tendon; SS repairs failed by shearing of fibers within the FDS. Load at first failure, ultimate load, and repair stiffness were all significantly different between SS and PT techniques; in all cases, the mean value for SS was higher than for PT. CONCLUSIONS: The SS repair using a cross-stitch suture technique was significantly stronger and stiffer than the PT repair using a mattress suture technique. This suggests that using SS repairs could enable patients to load the repair soon after surgery. Ultimately, this should reduce the risk of developing adhesions and result in improved functional outcome and fewer complications in the acute postoperative period. Future work will address the specific mechanisms (eg, suture-throw technique and tendon-weave technique) that underlie the improved strength and stiffness of the SS repair.
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| 26. |
- Bunketorp Käll, Lina, 1975, et al.
(författare)
-
Adaptive motor cortex plasticity following grip reconstruction in individuals with tetraplegia
- 2018
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Ingår i: Restorative Neurology and Neuroscience. - : IOS Press. - 0922-6028 .- 1878-3627. ; 36:1, s. 73-82
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Tendon transfer is a surgical technique for restoring upper limb motor control in patients with cervical spinal cord injuries (SCI), and offers a rare window into cortical neuroplasticity following regained arm and hand function. Objective: Here, we aimed to examine neuroplasticity mechanisms related to re-established voluntary motor control of thumb flexion following tendon transfer. Methods: We used functional Magnetic Resonance Imaging (fMRI) to test the hypothesis that restored limb control following tendon transfer is mediated by activation of that limb's area of the primary motor cortex. We examined six individuals with tetraplegia who underwent right-sided surgical grip reconstruction at Sahlgrenska University Hospital, Sweden. All were right-handed males, with a SCI at the C6 or C7 level, and a mean age of 40 years (range = 31-48). The average number of years elapsed since the SCI was 13 (range = 6-26). Six right-handed gender-and age-matched control subjects were included (mean age 39 years, range = 29-46). Restoration of active thumb flexion in patients was achieved by surgical transfer of one of the functioning elbow flexors (brachioradialis), to the paralyzed thumb flexor (flexor pollicis longus). We studied fMRI responses to isometric right-sided elbow flexion and key pinch, and examined the cortical representations within the left hemisphere somatomotor cortex a minimum of one year after surgery. Results: Cortical activations elicited by elbow flexion did not differ in topography between patients and control participants. However, in contrast to control participants, patients' cortical thumb flexion activations were not topographically distinct from their elbow flexion activations. Conclusion: This result speaks against a topographic reorganization in which the thumb region regains thumb control following surgical tendon transfer. Instead, our findings suggest a neuroplastic mechanism in which motor cortex resources previously dedicated to elbow flexion adapt to control the thumb.
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| 27. |
- Bunketorp Käll, Lina, 1975, et al.
(författare)
-
Essential gains and health after upper-limb tetraplegia surgery identified by the International classification of functioning, disability and health (ICF)
- 2017
-
Ingår i: Spinal Cord. - : Springer Science and Business Media LLC. - 1362-4393 .- 1476-5624. ; 55:9, s. 857-863
-
Tidskriftsartikel (refereegranskat)abstract
- Study Design: A questionnaire-based survey. Objectives: To describe functional gains and health following upper-limb tetraplegia surgery using the International Classification of Functioning, Disability and Health (ICF) as a reference and to explore interconnections across different dimensions of functioning and health. Setting: A specialized center for advanced reconstruction of extremities at Sahlgrenska University Hospital, Gothenburg, Sweden. Methods: Fifty-seven individuals who participated in a satisfaction survey were included in the present study. Besides questions concerned with the respondents' satisfaction with different aspects of surgery, the measures included perceived overall health status (EQ-VAS) and achieved grip strength. Univariate analyses were used to explore interconnections between measures. Results: The gains could be subcategorized and linked to the ICF domains 'mobility', 'self-care', 'communication', 'domestic life', and 'community, social and civic life', with 'handling objects' and 'maneuvering a wheelchair' as the most frequently reported gains. The mean EQ-VAS score was 67 +/- 22. No significant correlation was shown between grip strength and activity gains, nor between grip strength and perceived overall health. The degree of satisfaction was, however, associated with self-reported overall health among participants. Conclusion: The functional gains achieved after tetraplegia surgery could be applied to the ICF constructs' body functions/structures and activity with possible implications on participation. The overall health perception was relatively high and could be linked to the degree of satisfaction among participants. Muscle strength is not necessarily transferable to activity performance. This emphasizes the importance of addressing factors other than strength in the post-surgical rehabilitation and assessments.
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| 28. |
- Bunketorp Käll, Lina, 1975, et al.
(författare)
-
Regional estimates of cortical thickness in brain areas involved in control of surgically restored limb movement in patients with tetraplegia.
- 2020
-
Ingår i: The journal of spinal cord medicine. - : Informa UK Limited. - 2045-7723 .- 1079-0268. ; 43:4, s. 462-469
-
Tidskriftsartikel (refereegranskat)abstract
- Spinal cord injury (SCI) causes atrophy of brain regions linked to motor function. We aimed to estimate cortical thickness in brain regions that control surgically restored limb movement in individuals with tetraplegia.Cross-sectional study.Sahlgrenska University hospital, Gothenburg, Sweden.Six individuals with tetraplegia who had undergone surgical restoration of grip function by surgical transfer of one elbow flexor (brachioradialis), to the paralyzed thumb flexor (flexor pollicis longus). All subjects were males, with a SCI at the C6 or C7 level, and a mean age of 40 years (range=31-48). The average number of years elapsed since the SCI was 13 (range=6-26).We used structural magnetic resonance imaging (MRI) to estimate the thickness of selected motor cortices and compared these measurements to those of six matched control subjects. The pinch grip control area was defined in a previous functional MRI study.Compared to controls, the cortical thickness in the functionally defined pinch grip control area was not significantly reduced (P=0.591), and thickness showed a non-significant but positive correlation with years since surgery in the individuals with tetraplegia. In contrast, the anatomically defined primary motor cortex as a whole exhibited substantial atrophy (P=0.013), with a weak negative correlation with years since surgery.Individuals with tetraplegia do not seem to have reduced cortical thickness in brain regions involved in control of surgically restored limb movement. However, the studied sample is very small and further studies with larger samples are required to establish these findings.
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| 29. |
- Bunketorp Käll, Lina, 1975, et al.
(författare)
-
Satisfaction with upper limb reconstructive surgery in individuals with tetraplegia: the development and reliability of a Swedish self-reported satisfaction questionnaire.
- 2017
-
Ingår i: Spinal cord. - : Springer Science and Business Media LLC. - 1476-5624 .- 1362-4393. ; 55, s. 664-671
-
Tidskriftsartikel (refereegranskat)abstract
- A questionnaire-based survey.To assess satisfaction after upper limb reconstructive surgery in individuals with tetraplegia and to determine the reliability of a Swedish satisfaction questionnaire.A center for advanced reconstruction of extremities, Gothenburg, Sweden.Seventy-eight individuals with tetraplegia were invited to participate in the survey assessing satisfaction with the result of surgery across various domains. Measures of reliability included stability and internal consistency of domains consisting questions regarding global satisfaction, activities and occupation/schooling.Fifty-eight individuals (76%) participated, among whom 47 (82%) completed the questionnaire twice for repeatability assessment. The responses in the domains relating to global satisfaction, activities and occupation/schooling were positive in 83%, 72% and 31% of participants, respectively. Ninety-five percent felt they had benefited from the surgery, and 86% felt that the surgery had made a positive impact on their life. The psychometric testing indicated that the questionnaire yields scores that are reliable by both test-retest and internal consistency, with the exception of the domain occupation/schooling that had a high prevalence of missing and neutral responses and seemingly represents separate and distinct entities.Surgical rehabilitation of the upper limb in tetraplegia is highly beneficial and rewarding from a patient perspective, leading to satisfactory gains in activities of daily living as well as enhanced quality of life. The questionnaire is a reliable instrument for measuring satisfaction after surgery. However, occupationally and educationally related aspects of the surgical outcome should constitute separate domains, and further modifications of the questionnaire are thus recommended.Spinal Cord advance online publication, 21 February 2017; doi:10.1038/sc.2017.12.
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| 30. |
- Byström, Martin, et al.
(författare)
-
Five-Year Results of a Randomized, Controlled Trial of Collagenase Treatment Compared With Needle Fasciotomy for Dupuytren Contracture
- 2022
-
Ingår i: Journal of Hand Surgery. - : Elsevier BV. - 0363-5023. ; 47:3, s. 211-217
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Over the past decade, collagenase treatment and needle fasciotomy (NF) have gained widespread popularity in the treatment of Dupuytren contracture. This prospective study was designed to compare the results of these treatments in terms of clinical and patient-reported outcomes. Methods: A prospective, randomized, controlled trial included patients with a contracture of 20° or more in a single metacarpophalangeal joint. Patients were allocated to treatment with either NF or collagenase Clostridium histolyticum. The primary outcome was a reduction in the metacarpophalangeal joint contracture to less than 5°. Secondary outcomes included recurrence, the presence of Dupuytren cords, and changes in patient-reported outcomes. The participants were examined 5 years after the intervention. Results: The study cohort comprised 156 patients divided into 2 equally sized groups. After 5 years, data were collected from 143 (92 %) of the initially enrolled participants. The mean time for the clinical follow-up was 5.1 years. In the remaining cohort without a second procedure, 51% (23 patients) in the collagenase Clostridium histolyticum group and 47% (27 patients) in the NF group still had extension deficits of less than 5°. Among the participants with a successful initial procedure, the recurrence rate was 56% (36 patients) in the collagenase Clostridium histolyticum group and 45% (30 patients) in the NF group. There were no differences between the 2 treatments in regard to passive joint extension, reduction of contracture, range of motion, or patient-reported outcomes. Conclusions: The 5-year outcomes for NF are similar to those for collagenase in terms of sustained correction, recurrence, presence of Dupuytren cords, and patient-reported outcomes for the treatment of metacarpophalangeal joint contractures. Type of study/level of evidence: Therapeutic I. © 2021 American Society for Surgery of the Hand
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| 31. |
- Dahlgren, A, et al.
(författare)
-
Activity performance and upper extremity function in cervical spinal cord injury patients according to the Klein-Bell ADL Scale.
- 2007
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Ingår i: Spinal cord : the official journal of the International Medical Society of Paraplegia. - : Springer Science and Business Media LLC. - 1362-4393. ; 45:7, s. 475-84
-
Tidskriftsartikel (refereegranskat)abstract
- STUDY DESIGN: Cross-sectional study. OBJECTIVES: (1) To examine whether the Klein-Bell ADL Scale (K-B Scale) discriminates cervical spinal cord injury (SCI) patients in daily activities and to explore its applicability in this group of patients. (2) To examine the association between basic ADL and upper extremity function. (3) To investigate if grip ability can be discerned in the scale. SETTING: Spinal Cord Injury Unit, Sahlgrenska University Hospital, Göteborg, Sweden. METHODS: Fifty-five patients with cervical SCI with no prior reconstructive hand surgery were included in the study. Analyses of the patient's independence were made according to the K-B Scale. Three additional analyses were carried out, the first examined whether the use of assistive devices and house and car adaptations influenced independence. The last two used different approaches to investigate whether arm and grip function could be detected in the K-B scale. RESULTS: Raw score in the K-B Scale can discriminate for independence in daily activities but the scale's weight scheme does not function for cervical SCI patients. Assistive devices and car and house adaptations can compensate for dependence in daily activities. Lack of grip function decreases the patient's ability to become independent. Diagnosis-related activities cannot be assessed in all items. CONCLUSION: The K-B Scale's raw score was useful assessing daily activities in cervical SCI patients. Its reliability in conjunction with arm and grip function in patients with cervical SCI has yet to be proven.
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| 32. |
- Dahlgren, Jörgen, et al.
(författare)
-
Strategiska vägval : En utredning om vetenskaplig informationsförsörjning vid Linköpings universitet
- 2003
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Tillgång till information i dess skilda former utgör en grundläggande och nödvändig förutsättning för universitetets verksamhet, för utbildningen och för forskningen. Utvecklingen på IT-området resulterar efterhand i nya vägar för att söka och finna information i växande mängder. Jämsides med detta pågår en förändring på utbildningsområdet, varmed tyngdpunkten förskjuts från undervisning till lärande och i ett livslångt perspektiv. För att förädla det s.k. informationssamhället till Kunskapssamhälle krävs god förmåga att finna, värdera och bearbeta information, vetenskaplig och annan. Vikten därav för vetenskaplig kunskapsutveckling, för problemlösning och kvalificerat beslutsfattande blir alltmer uppenbar. Utifrån utvecklingstendenser som dessa tillsatte rektor vid Linköpings universitet en särskild utredning i mars 2002. Den fick uppgiften att lämna förslag i syfte att öka ”studenternas och de anställdas möjligheter att ta tillvara och i universitetets verksamhet på ett kostnadseffektivt sätt nyttiggöra den moderna informationsteknikens potential för spridning av och sökande efter kunskap.” I sammanhanget riktades särskilt intresse mot universitetsbiblioteket som en pedagogisk resurs inom universitetet. Vidare efterfrågades en analys av formerna för finansiering och strategisk ledning av vetenskaplig informationsförsörjning vid Linköpings universitet.Strategiska vägval innehåller den slutförda utredningens fyra delstudier: Informationsförsörjning och pedagogisk utveckling, Mediemarknadens utmaningar, Elektronisk publicering vid Linköpings universitet samt Organisation och finansiering av biblioteksverksamheten vid Linköpings universitet.
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| 33. |
- Dahlgren, Jörgen, et al.
(författare)
-
Strategiska vägval : Slutbetänkande
- 2003
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Tillgång till information i dess skilda former utgör en grundläggande och nödvändig förutsättning för universitetets verksamhet, för utbildningen och för forskningen. Utvecklingen på IT-området resulterar efterhand i nya vägar för att söka och finna information i växande mängder. Jämsides med detta pågår en förändring på utbildningsområdet, varmed tyngdpunkten förskjuts från undervisning till lärande och i ett livslångt perspektiv. För att förädla det s.k. informationssamhället till Kunskapssamhälle krävs god förmåga att finna, värdera och bearbeta information, vetenskaplig och annan. Vikten därav för vetenskaplig kunskapsutveckling, för problemlösning och kvalificerat beslutsfattande blir alltmer uppenbar.Utifrån utvecklingstendenser som dessa tillsatte rektor vid Linköpings universitet en särskild utredning i mars 2002. Den fick uppgiften att lämna förslag i syfte att öka ”studenternas och de anställdas möjligheter att ta tillvara och i universitetets verksamhet på ett kostnadseffektivt sätt nyttiggöra den moderna informationsteknikens potential för spridning av och sökande efter kunskap.” I sammanhanget riktades särskilt intresse mot universitetsbiblioteket som en pedagogisk resurs inom universitetet. Vidare efterfrågades en analys av formerna för finansiering och strategisk ledning av vetenskaplig informationsförsörjning vid Linköpings universitet.Strategiska vägval innehåller den slutförda utredningens fyra delstudier: Informationsförsörjning och pedagogisk utveckling, Mediemarknadens utmaningar, Elektronisk publicering vid Linköpings universitet samt Organisation och finansiering av biblioteksverksamheten vid Linköpings universitet.
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| 34. |
- Dahlin, L., et al.
(författare)
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Handtransplantation och implantation av nervchips. Flera nyheter på väg inom handkirurgin.
- 2000
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Ingår i: Ugeskrift for Laeger. - 0041-5782. ; 162:12, s. 1725-1730
-
Forskningsöversikt (refereegranskat)abstract
- Injuries and diseases of the hand naturally have an enormous impact on hand function and on quality of life, both occupational and social. The majority of hand-injury patients are under 30 years of age. Hand surgery, an established specialty in Sweden since 1969, is of great importance in terms of clinical developments, education and research. In the coming decade, scientific and clinical advances are to be expected in several fields such as nerve injuries including brachial plexus lesion, microsurgery, flexor tendon injuries and tendon transfer. Bioimplant research and new advances at the biotechnological interface will yield new options in nerve reconstruction, microchip implants in the nervous system, and the restoration of muscle-tendon function following injury. Artificial limbs with advanced motor and sensory functions will be important future aids in the rehabilitation of amputees. Transplantation of human hands is another promising reconstructive procedure which may open iup new perspectives in the coming millennium.
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| 35. |
- Einarsson, Fredrik, 1968, et al.
(författare)
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Muscle biopsies from the supraspinatus in retracted rotator cuff tears respond normally to passive mechanical testing: a pilot study
- 2011
-
Ingår i: Knee surgery, sports traumatology, arthroscopy. - : Springer Science and Business Media LLC. - 1433-7347 .- 0942-2056. ; 19:3, s. 503-507
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The aim of the present study was to assess the function of the isolated muscle component in retracted rotator cuff tears. METHODS: Muscle biopsies were harvested from the supraspinatus and the ipsilateral deltoid in seven patients undergoing surgery for a large, retracted rotator cuff tear. Single fibres and fibre bundles were subjected to passive stretching in vitro with subsequent recordings of tension and sarcomere lengths using the laser diffraction technique. Stress-strain curves were plotted, and the elastic modulus was calculated for all preparations. Morphology was evaluated with regard to collagen fraction, ratio between fast and slow fibres, fibre size and fibre size variability using standard staining techniques. RESULTS: Intra-individual comparisons of the stress-strain curves showed a high degree of conformity in terms of both shape and tangent values, and there were no statistically significant differences in the elastic modulus for single fibres and bundles in the deltoid and supraspinatus muscles, respectively, supported by the analysis of the observed confidence interval of the differences between the paired values of the elastic modulus. There were no differences in collagen content, fibre size and ratio between fast and slow fibres in the deltoid and supraspinatus muscles, respectively. CONCLUSION: We conclude that muscle biopsies from the supraspinatus in retracted rotator cuff tears respond normally to mechanical testing in vitro.
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| 36. |
- Einarsson, Fredrik, 1968, et al.
(författare)
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Subscapularis muscle mechanics in children with obstetric brachial plexus palsy
- 2008
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Ingår i: The Journal of Hand Surgery (European Volume). - : SAGE Publications. - 1753-1934 .- 2043-6289. ; 33:4, s. 507-12
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigates the passive mechanical properties of the subscapularis muscle in children with a contracture as a result of obstetrical brachial plexus palsy. Muscle biopsies were harvested from nine children undergoing open surgery for shoulder contracture. Passive mechanical testing of single cells and muscle bundles was performed. Corresponding comparisons were made using muscle biopsies from seven healthy controls. Single muscle fibres from patients with obstetric brachial plexus palsy displayed a shorter slack sarcomere length, linear deformation of the fibre within a wider zone of sarcomere length and a greater relative increase in stiffness compared with muscle bundles. We conclude that secondary changes in muscle fibre properties will occur as a result of a longstanding lack of sufficient passive stretch, leading to compensatory changes in the extracellular matrix. These results suggest the presence of a dynamic feedback system constituting a muscle-to-extracellular matrix communication interface.
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| 37. |
- Ejeskär, Arvid, 1940, et al.
(författare)
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Clinical and radiographic evaluation of surgical reconstruction of finger flexion in tetraplegia
- 2005
-
Ingår i: J Hand Surg [Am]. - : Elsevier BV. - 0363-5023. ; 30:4, s. 842-9
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To define the order and frequency of elongation in tendon junctions in extensor carpi radialis longus (ECRL) to flexor digitorum profundus tendon transfer and its correlation to grip strength and lack of finger flexion. METHODS: Forty-seven tetraplegic patients had surgery involving the reconstruction of finger flexion with the transfer of the ECRL in a total of 62 arms. During surgery metal markers were placed on both sides of the tendon-to-tendon attachment site. After surgery the distance between the markers was measured on radiographs. Any increase in the distance between the markers was judged as elongation. The grip strength and mean pulp-to-palm distance were evaluated a minimum of 6 months after surgery. Three arms had a second surgery because of insufficient functional results. RESULTS: The average final elongation was 9 +/- 10 mm (mean +/- SD). The mean grip strength was 16 +/- 12 kPa (range, 0-50). The lack of flexion (mean value of pulp-to-distal palmar crease of 3 ulnar digits) was 0.8 +/- 1.2 cm on average. Elongation up to 15 to 20 mm still was compatible with good grasp. CONCLUSIONS: The tendon junction after a transfer of the ECRL to the finger flexors can be overloaded. Elongation therefore must be considered as one among several possible causes of an unsatisfactory result after this type of tendon transfer but elongation less than 15 mm usually is compatible with excellent function.
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| 38. |
- Fischer, Per, 1981-
(författare)
-
Hemi and total wrist arthroplasty
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Aim: To study implant survival and implant loosening following primary total wrist arthroplasty (TWA) using four different implants. To report outcome following wrist revision arthroplasty. To evaluate a new radial wrist hemi arthroplasty (RWHA) design clinically and biomechanically.Method: The studies included 136 primary TWAs and 16 revision TWAs, both studies with prospectively collected data. Six fresh frozen cadaveric wrist specimen were used for biomechanical analysis. The RHWA was evaluated clinically in a pilot series of 20 cases.Results: Total implant survival was 92% but with high frequency of implant loosening of surviving Re-Motion implants. None of the surviving Maestro implants were considered radiographically loose. Implant survival following revision arthroplasty was 75%, considerably lower than following primary TWAs. However, none of the patients with surviving revision implants had pain at rest and little or no pain in activity. The surgical procedure and placement of the RHWA was feasible. Overall, the kinematic and functional changes appeared acceptable compared to the native wrist. None of the patients underwent revision following RHWA but reoperation was performed in 7 patients on the indication of persistent pain. However, patients reported relief of pain and improvement of patient-reported outcome measures.Conclusion: High long-term implant survival and no signs of radiographic loosening was found for the Maestro implant. However, the Maestro implant is no longer available on the market and we believe there is a need for new TWA designs. Revision arthroplasty is a valid option in the management of failed TWA. However, implant survival is lower than for primary TWAs and as many as 25% require additional surgery. Promising results were found using the new RHWA design but the implant needs modification before further testing.
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| 39. |
- Fridén, Jan, et al.
(författare)
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Effect of muscle tension during tendon transfer on sarcomerogenesis in a rabbit model
- 2000
-
Ingår i: Journal of Hand Surgery-American Volume. - Philadelphia : Saunders Elsevier. - 0363-5023 .- 1531-6564. ; 25:1, s. 138-143
-
Tidskriftsartikel (refereegranskat)abstract
- Sarcomere number change was investigated in an animal model of tendon transfer. In 9 adult New Zealand white rabbits, the flexor digitorum longus muscle was cut distally and transferred and woven into the tibialis anterior tendon. Ankles were then immobilized for 3 weeks in 75 degrees flexion. Transferred flexor digitorum longus muscles were harvested and complete architectural analysis was performed. Sarcomere lengths were measured using laser diffraction. Serial sarcomere number in transferred flexor digitorum longus fibers was a strong function of the sarcomere length at the time of transfer. A highly significant negative correlation between these 2 parameters was approximated by a linear relationship. Based on this finding, we conclude that serial sarcomere number is significantly affected by the degree of stretch during the transfer itself. This could easily compromise the purpose of surgical tendon transfer by reducing the procedure to little more than a tenodesis.
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| 40. |
- Fridén, Jan, 1953-
(författare)
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Exercise-induced muscle soreness : a qualitative and quantitative study of human muscle morphology and function
- 1983
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Exercise-induced muscle soreness is characterized by stiffness, tenderness and pain during active movements and weakness of the affected musculature the days after unusually or particularly heavy work. The most pronounced subjective symptoms do not arise immediately but rather between a couple of hours to some days after the exercise (a delayed-onset of muscle soreness), the intensity of pain is greatest about 48 hours after the work. A particular association exists between muscle soreness and eccentric contractions. Despite the fact that muscle soreness is a well known phenomenon in the sphere of sports as well as working life, the pathophysiological mechanisms underlying this are still not understood.In the present study a detailed analysis of human muscle fibre population structure after high tension work (eccentric exercise) that gave rise to muscle soreness, was carried out. The objective was to elucidate how fibres of different types are influenced by repeated muscle contractions reaching extreme tension levels using qualitative and quantitative light and electron microscopic techniques. It was hoped that such morphological analysis would provide a basis for discussion of possible causes for muscle soreness. The muscle function after the work was measured by isokinetic methods.To improve the basis for the ultrastructural analysis the fibre populations in untrained and endurance trained human m. vastus lateralis of age-matched individuals were classified into different fibre type groups according to their ultrastructure. The selective glycogen depletion from Type 1 fibres seen after long term submaximal work, visualized electron microscopically with PA-TSC-SP staining, substantiated the usefulness of the appearance of the M-band to differentiate between fibre types. Stereological data showed that neither volume density of mitochondria nor of lipid droplets provide sufficient criteria to differentiate between fibre types.After an eccentric exercise regimen sore muscles (m. soleus or m. vastus lateralis) showed disturbances of the cross striated band pattern. Fibres with disorganized myofibrillar material made up 1/3, 1/2 and 1/10 of the analysed material, 1 hour, 3 and 6 days after exercise, respectively. The myofibrillar lesions were preferably localized in the Z-band. This showed streaming, broadening and sometimes total disruption. The Type 2 fibres were most affected.The reduction of strength was greatest with the most rapid contractions. Strength remained decreased the period when the structural damage was most pronounced. Eight weeks of eccentric muscle training reduced all the above negative effects.The results indicate that the Z-disc constitute the weak link in the myofibrillar contractile chain at high muscle tensions. It is suggested that the myofibrillar lesions are a direct result of mechanical tearing. Rupture of myofibrils is thought to result in formation of protein components and a con- sequental release of protein bound ions that via osmosis result in oedema and soreness. Training, using eccentric contractions over a long period of time leads to adaptations at the fibre level by a reorganization of the contractile apparatus as well as an optimization of nervous coordination.
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| 41. |
- Fridén, Jan, 1953, et al.
(författare)
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Fiber length variability within the flexor carpi ulnaris and flexor carpi radialis muscles: implications for surgical tendon transfer
- 2004
-
Ingår i: J Hand Surg [Am]. - : Elsevier BV. - 0363-5023. ; 29:5, s. 909-14
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The purpose of this study was to understand the detailed architectural properties of the human flexor carpi radialis (FCR) and flexor carpi ulnaris (FCU) muscles and their implications for tendon transfer surgery. METHODS: Muscle fiber length was measured in 6 separate regions of the FCU and FCR from 10 cadaveric specimens. Sarcomere length was measured by laser diffraction for normalization. Moment arms were estimated by measuring tendon excursion with respect to joint angle. The position of entry of the motor nerve branches into each muscle also was measured to establish limits for the safe length of muscle mobilization. RESULTS: Muscle fiber length varied significantly along both the FCU and FCR. Fiber length variability in the FCU was twice that of the FCR. Although the average fiber length for both muscles across all regions was similar (62.6 +/- 2.1 mm for the FCR and 63.1 +/- 4.0 mm for the FCU), the proximal fibers of the FCU were longer compared with the proximal fibers of the FCR and the distal fibers of the FCU were shorter compared with the distal fibers of the FCR. The 99% confidence interval for the second nerve branch entry into the muscles was located approximately 69 mm distal to the medial epicondyle for the FCU and approximately 73 mm distal for the FCR. CONCLUSIONS: These data show different designs of both the FCU and the FCR. The functional significance of fiber length variability is not clear but imply that, when used in tendon transfer, the properly mobilized FCU has a much greater excursion.
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| 42. |
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| 43. |
- Fridén, Jan, 1953, et al.
(författare)
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Mechanical feasibility of immediate mobilization of the brachioradialis muscle after tendon transfer
- 2010
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Ingår i: The Journal of Hand Surgery. - : Elsevier BV. - 1531-6564 .- 0363-5023. ; 35:9, s. 1473-1478
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Tendon transfer is often used to restore key pinch after cervical spinal cord injury. Current postoperative recommendations include elbow immobilization in a flexed position to protect the brachioradialis-flexor pollicis longus (BR-FPL) repair. The purpose of this study was to measure the BR-FPL tendon tension across a range of wrist and elbow joint angles to determine whether joint motion could cause repair rupture. METHODS: We performed BR-to-FPL tendon transfers on fresh-frozen cadaveric arms (n = 8) and instrumented the BR-FPL tendon with a buckle transducer. Arms were ranged at 4 wrist angles from 45 degrees of flexion to 45 degrees of extension and 8 elbow angles from 90 degrees of flexion to full extension, measuring tension across the BR-FPL repair at each angle. Subsequently, the BR-FPL tendon constructs were removed and elongated to failure. RESULTS: Over a wide wrist and elbow range of motion, BR-FPL tendon tension was under 20 N. Two-way analysis of variance with repeated measures revealed a significant effect of wrist joint angle (p<.001) and elbow joint angle (p<.001) with significant interaction between elbow and joint angles (p<.001). Because the failure load of the repair site was 203 +/- 19 N, over 10 times the loads that would be expected to occur at the repair site, our results demonstrate that the repair has a safety factor of at least 10. CONCLUSIONS: Our tendon force measurements support the assertion that the elbow joint need not be immobilized when the BR is used as a donor muscle in tendon transfer to the FPL. This is based on the fact that maximum passive tendon tension was only about 20 N in our cadaveric model and the failure strength of this specific repair was over 200 N. We suggest that it is possible to consider performing multiple tendon transfers in a single stage, avoiding immobilization, which may adversely affect functional recovery. These results must be qualified by the fact that issues unique to living tissues such as postoperative edema and tendon gliding cannot be accounted for by this cadaveric model.
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| 44. |
- Fridén, Jan, 1953, et al.
(författare)
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Novel concepts integrated in neuromuscular assessments for surgical restoration of arm and hand function in tetraplegia.
- 2012
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Ingår i: Physical medicine and rehabilitation clinics of North America. - : Elsevier BV. - 1558-1381 .- 1047-9651. ; 23:1, s. 33-50
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Tidskriftsartikel (refereegranskat)abstract
- Surgical restoration of key functions of the upper extremity has tremendous potential to increase autonomy, mobility, and self-esteem by resuming critical abilities in patients with tetraplegia. New strategies of surgical reconstruction and postoperative rehabilitation of upper extremity function in tetraplegic patients have been developed, based on basic science and clinical studies. In contrast to traditional hand reconstruction with separate flexors and extensors phases, combining 7 individual procedures provides key pinch and finger flexion together with passive opening of hand in one stage. Further research should aim at combining traditional algorithms with new approaches, such as immediate postoperative activation, combined procedures and nerve transfers.
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| 45. |
- Fridén, Jan, 1953, et al.
(författare)
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Passive muscle-tendon amplitude may not reflect skeletal muscle functional excursion
- 2006
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Ingår i: J Hand Surg [Am]. - : Elsevier BV. - 0363-5023. ; 31:7, s. 1105-10
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To quantify the gain in muscle mobility with progressive release of surrounding connective-tissue structures and to compare this property with the known architecture of each muscle. METHODS: Each of 5 different muscle tendon units (extensor carpi radialis brevis, extensor carpi radialis longus, flexor carpi ulnaris, flexor digitorum superficialis, pronator teres) was released from its insertion and secured into the jaws of a clamp attached to a servomotor that could be operated under length or force control to simulate the load placed on the tendon by a surgical assistant. A constant load of 5 N was applied to the tendon while the muscle-tendon unit was released surgically from the surrounding tissue in 1-cm increments. Mobility was plotted against release distance and analyzed by linear regression to yield mobility gain, the slope of the regression equation. One-way analysis of variance was used to compare mobility gain among muscles. RESULTS: In contrast to previous results from the brachioradialis muscle in which the mobility gain was large and highly nonlinear, mobility gain was small, consistent, and linear for all muscles studied. The smallest mobility gain was for the flexor digitorum superficialis and was highly linear. The largest gain was for the pronator teres and again was highly linear. In general, the mobility gain for the extensor carpi radialis brevis was similar to that of the extensor carpi radial longus. The flexor carpi ulnaris muscle was difficult to mobilize, and its gain was modest. There was no significant correlation between mobility gain of the forearm muscles during progressive release and the length of their fibers. CONCLUSIONS: The small mobility and complete lack of correlation with fiber length provide strong evidence that mobility gain does not accurately reflect muscle excursion as it is typically described. This calls into question the general practice of tensioning muscles by first passively extending the muscle and then choosing the attachment length as a particular portion of that passive relationship.
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| 46. |
- Fridén, Jan, 1953, et al.
(författare)
-
Reach out and grasp the opportunity: reconstructive hand surgery in tetraplegia
- 2019
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Ingår i: Journal of Hand Surgery-European Volume. - : SAGE Publications. - 1753-1934 .- 2043-6289. ; 44:4, s. 343-353
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Tidskriftsartikel (refereegranskat)abstract
- Reconstructive upper extremity surgeries in tetraplegia are technically challenging because of the many complicated real-time decisions that need to be made, e.g. extent of release of donor muscle-tendon complex, routing of donor muscles, tissue preparation and optimization, tensioning of muscle-tendon units, balancing joints and suturing tendon-to-tendon attachments. Nerve transfer surgeries can add functionality but also make the reconstruction planning more complex. In this overview, we present some of the fundamental muscle-tendon-joint mechanics studies that allow for single-stage surgical reconstruction of hand function as well as early postoperative activity-based training in patients with cervical spinal cord injuries. We foresee an increased need for studies addressing combined nerve and tendon transfer reconstructions in parallel with patient-perceived outcome investigations. These should be combined with implementation of assistive technology such as functional electrical stimulation for diagnostic, prognostic and training purposes.
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| 47. |
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| 48. |
- Fridén, Jan, 1953, et al.
(författare)
-
Simultaneous powering of forearm pronation and key pinch in tetraplegia using a single muscle-tendon unit.
- 2012
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Ingår i: The Journal of hand surgery, European volume. - 2043-6289. ; 37:4, s. 323-328
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Tidskriftsartikel (refereegranskat)abstract
- This study clinically assessed the concept that both thumb flexion and forearm pronation can be restored by brachioradialis (BR)-to-flexor pollicis longus (FPL) tendon transfer if the BR is passed dorsal to the radius. Six patients [two women and four men, mean age 32.3 years (SD 4.9, range 23-56)] underwent BR-to-FPL transfer dorsal to the radius and through the interosseous membrane (IOM). Lateral key pinch strength and pronation range of motion (ROM) were measured 1 year after surgery. A group of six patients [two women and four men, mean age 31.2 years (SD 5.0, range 19-52)] who underwent traditional palmar BR-to-FPL was included for comparison. Postoperative active pronation was significantly greater in the dorsal transfer group compared to the palmar group [149 (SD 6) and 75 (SD 3), respectively] and pinch strength was similar in the two groups [1.28 (SD 0.16) kg and 1.20 (SD0.21) kg, respectively]. We conclude that it is feasible to reconstruct lateral key pinch and forearm pronation simultaneously using only the BR motor.
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| 49. |
- Fridén, Jan, 1953, et al.
(författare)
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Tetraplegia Management Update
- 2015
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Ingår i: Journal of Hand Surgery-American Volume. - : Elsevier BV. - 0363-5023. ; 40:12, s. 2489-2500
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Tidskriftsartikel (refereegranskat)abstract
- Tetraplegia is a profound impairment of mobility manifesting as a paralysis of all 4 extremities owing to cervical spinal cord injury. The purpose of this article is to provide an update and analyze current management, treatment options, and outcomes of surgical reconstruction of arm and hand function. Surgical restoration of elbow and wrist extension or handgrip has tremendous potential to improve autonomy, mobility, and critical abilities, for example, eating, personal care, and self-catheterization and productive work in at least 70% of tetraplegic patients. Tendon and nerve transfers, tenodeses, and joint stabilizations reliably enable improved arm and hand usability, reduce muscle imbalance and pain in spasticity, and prevent joint contractures. One-stage combined procedures have proven considerable advantages over traditional multistage approaches. Immediate activation of transferred muscles reduces the risk of adhesions, facilitates relearning, avoids adverse effects of immobilization, and enhances functional recovery. Transfer of axillary, musculocutaneous, and radial nerve fascicles from above the spinal cord injury are effective and promising options to enhance motor outcome and sensory protection, especially in groups with limited resources. Improved communication between medical disciplines, therapists, patients, and their relatives should help that more individuals can benefit from these advances and could empower many thousands tetraplegic individuals "to take life into their own hands" and live more independently.
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| 50. |
- Fridén, Jan, 1953, et al.
(författare)
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The Extensor Pollicis Longus-Loop-Knot (ELK) Procedure for Dynamic Balance of the Paralyzed Thumb Interphalangeal Joint.
- 2013
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Ingår i: Techniques in hand & upper extremity surgery. - 1531-6572. ; 17:4, s. 184-6
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Tidskriftsartikel (refereegranskat)abstract
- Hyperflexion of the thumb interphalangeal (IP) joint interferes significantly with pinching between the thumb and the index finger in a paralyzed hand. The extensor pollicis longus-loop-knot (ELK) procedure was used successfully in 7 tetraplegic patients to balance the IP joint between strong restored flexor function and lacking or weak antagonism of the thumb extensors. A V-shaped incision was made over the extensor hood at the level of the IP joint, the extensor pollicis longus (EPL) tendon was elevated, a loop was formed, secured by sutures, and then turned proximally onto the EPL tendon itself and fixed on both sides. The operation reliably limited the maximum range of IP flexion at 20 to 30 degrees from neutral. Postoperative problems did not occur. The ELK procedure is easy and quick and secures the optimal setting of IP flexion with limited flexibility, which is advantageous compared with rigid bony arthrodesis. It also avoids certain disadvantages of the commonly used flexor pollicis longus split tenodesis and is therefore a valuable alternative for the correction of Froment's sign due to intrinsic or extrinsic paralysis of the thumb.
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