| 1. |
- Flinck, Marianne, et al.
(author)
-
Biomechanical comparison of semi-rigid pediatric locking nail versus titanium elastic nails in a femur fracture model.
- 2015
-
In: Journal of children's orthopaedics. - : SAGE Publications. - 1863-2521 .- 1863-2548. ; 9:1, s. 77-84
-
Journal article (peer-reviewed)abstract
- The treatment for length-unstable diaphyseal femur fractures among school-age children is commonly intramedullary elastic nails, with or without end caps. Another possible treatment is the semi-rigid pediatric locking nail (PLN). The purpose of this biomechanical study was to assess the stability of a length-unstable oblique midshaft fracture in a synthetic femur model stabilized with different combinations of intramedullary elastic nails and with a PLN.Twenty-four femur models with an intramedullary canal diameter of 10.0 mm were used. Three groups with various combinations of titanium elastic nails (TEN) with end caps and one group with a PLN were tested. An oblique midshaft fracture was created, and the models underwent compression, rotation, flexion/extension, and a varus/valgus test, with 50 and 100 % of the forces generated during walking in corresponding planes.We present the results [median (range)] from 100 % loading during walking. In axial compression, the PLN was less shortened than the combination with two 4.0-mm TEN [by 4.4 (3.4-5.4) mm vs. 5.2 (4.8-6.6) mm, respectively; p = 0.030]. No difference was found in shortening between the PLN and the four 3.0-mm TEN [by 7.0 (3.3-8.4) mm; p = 0.065]. The two 3.0-mm TEN did not withstand the maximum shortening of 10.0 mm. In external rotation, the PLN rotated 12.0° (7.0-16.4°) while the TEN models displaced more than the maximum of 20.0°. No model withstood a maximal rotation of 20.0° internal rotation. In the four-point bending test, in the coronal and the sagittal plane, all combinations except the two 3.0-mm TEN in extension withstood the maximum angulation of 20.0°.PLN provides the greatest stability in all planes compared to TEN models with end caps, even though the difference from the two 4.0-mm or four 3.0-mm TEN models was small.
|
|
| 2. |
- Janarv, Per-Mats
(author)
-
Anterior cruciate ligament injuries in children
- 2000
-
Doctoral thesis (other academic/artistic)abstract
- The thesis discusses the two most common injuries to the anterior cruciate ligament (ACL) in children: The rupture in the substance of the ACL and the anterior tibial spine (ATS) fracture. The latter is an avulsion fracture of the tibial attachment of the ACL. The injuries and their treatment are studied in two clinical papers. Two experimental studies in rabbits are connected to the clinical studies and focuses on two fields of evident interest in the treatment of the injuries: 1) The limitations of ACL reconstruction in children, with respect to drilling and tendon grafting across a growth plate (physis), and the risk of growth disturbances; and 2) The influence of growth on knee laxity after an ATS fracture. Twenty-eight consecutive children with ACL ruptures were followed for 3 - 5 years in order to describe the outcome of nonoperative treatment, to identify variables relevant to failure of nonoperative treatment, and to evaluate an over-the-top procedure for ACL reconstruction avoiding drill holes across the physes. 68% of the patients in whom nonoperative treatment was attempted had been operated on at follow-up, i.e. the injury has a marked impact on knee function in children. The patients not operated on were younger at the time of injury and had a lower activity level at follow-up. The surgical procedure improved knee function, but there was a correlation between high activity level and low subjective knee function indicating that the knee function was not completely restored. A controlled and measurable drill injury was made across the distal femoral physis in rabbits. The relative size of the drill injury necessary to cause growth disturbance was found to be 7 - 9%. A transphyseally placed tendon, even as a free graft, prevented solid bone bridge formation in the drill hole and growth disturbance. The results are of possible clinical significance when discussing improvement of ACL reconstruction in children. The long-term course of ATS fractures sustained in childhood was evaluated 10 - 39 years after injury in 61 adults. Age at injury, residual fracture displacement after healing, and the type of ATS fracture according to Meyers & McKeever were compared with objective and subjective knee function. The injury appears to be a relatively benign injury in the long term. The subjective knee function was excellent or good in 87% of the subjects. Age at injury did not influence the outcome. Only in patients with a totally avulsed ATS fragment (type 111), was there a correlation between residual fracture displacement and knee laxity, which in turn was correlated to subjective knee function. A method to measure anterior knee laxity in rabbits was developed using a materials testing machine. The results of the subsequent experimental study on the influence of growth on knee laxity after healing of a displaced ATS fracture type Ill, support the theory that further growth may reduce the functional elongation of the ACL caused by the fracture.
|
|
| 3. |
- Mostroem, Eva Bengtsson, et al.
(author)
-
Pre- and postcontrast T1 and T2 mapping of patellar cartilage in young adults with recurrent patellar dislocation
- 2015
-
In: Magnetic Resonance in Medicine. - : Wiley. - 1522-2594 .- 0740-3194. ; 74:5, s. 1363-1369
-
Journal article (peer-reviewed)abstract
- PurposeTo examine the cartilage quality in young adults with recurrent patellar dislocation in childhood using different magnetic resonance imaging parameters. MethodsSixteen young adults with unilateral recurrent patellar dislocation were investigated 5 y (mean, 8.5 y) after the first dislocation. Pre- and postcontrast T1 and precontrast T2 relaxation times were analyzed in four superficial and four deep patellar cartilage regions of both knees. Two hours after intravenous injection of 0.2 mM/kg Gd-DTPA(2-), postcontrast T1 [T1(Gd)] and R1 [1/T1 (precontrast)-1/T1 (postcontrast)] were analyzed in the regions. Muscle performance and patient-reported outcome were evaluated. ResultsWhen comparing the injured side with the noninjured side, differences were seen in the superficial half but not the deep half of the cartilage. T1(Gd) was shorter in the central part, whereas T2 was shorter in the periphery of the patellar cartilage (P<0.05). R1 demonstrated similar differences between healthy and diseased cartilage as T1(Gd) alone. The knee function was not correlated to the degenerative changes. ConclusionThe short T1(Gd) centrally indicates degenerative cartilage changes consistent with loss of glycosaminoglycans. Precontrast and R1 calculations may be excluded in clinical dGEMRIC, which simplifies the procedure. A decrease in T2 may be a very early sign of joint pathology but warrants further investigation. Magn Reson Med 74:1363-1369, 2015. (c) 2014 Wiley Periodicals, Inc.
|
|
| 4. |
- Schmitz, Jesper Kraus, et al.
(author)
-
Poorer patient-reported outcome and increased risk of revision at a 5-year follow-up among patients with septic arthritis following anterior cruciate ligament reconstruction: a register-based cohort study of 23,075 primary anterior cruciate ligament reconstructions
- 2023
-
In: Knee Surgery, Sports Traumatology, Arthroscopy. - : SPRINGER. - 0942-2056 .- 1433-7347. ; 31:10, s. 4090-4098
-
Journal article (peer-reviewed)abstract
- PurposeThe primary aim of this study is to analyse the patient-reported outcomes after ACLR complicated by septic arthritis. The secondary aim is to examine the 5-year risk of revision surgery after primary ACLR complicated by septic arthritis. The hypothesis was that patients with septic arthritis after ACLR are more likely to have lower PROMs scores and an increased risk of revision, compared with patients without septic arthritis.Materials and methodsAll primary ACLRs, with a hamstring or patellar tendon autograft (n = 23,075), in the Swedish Knee Ligament Register (SKLR) between 2006 and 2013 were linked with data from the Swedish National Board of Health and Welfare to identify patients with postoperative septic arthritis. These patients were verified in a nationwide medical records analysis and compared with patients without infection in the SKLR. The patient-reported outcome was measured using the Knee injury and Osteoarthritis Index Score (KOOS) and the European Quality of Life Five Dimensions Index (EQ-5D) at 1, 2 and 5 years postoperatively and the 5-year risk of revision surgery was calculated.ResultsThere were 268 events of septic arthritis (1.2%). The mean scores on the KOOS and EQ-5D index were significantly lower for patients with septic arthritis on all subscales on all follow-up occasions compared with patients without septic arthritis. Patients with septic arthritis had a revision rate of 8.2% compared with 4.2% in patients without septic arthritis (adjusted hazard ratio 2.04; confidence interval 1.34-3.12).ConclusionPatients suffering from septic arthritis following ACLR are associated with poorer patient-reported outcomes at 1-, 2- and 5-year follow-ups compared with patients without septic arthritis. The risk of revision ACL reconstruction within 5 years of the primary operation for patients with septic arthritis following ACLR is almost twice as high, compared with patients without septic arthritis.
|
|
