| 41. |
- Alfredson, Håkan, et al.
(författare)
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High thigh muscle strength but not bone mass in young horseback-riding females
- 1998
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Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 62:6, s. 497-501
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Tidskriftsartikel (refereegranskat)abstract
- To evaluate whether the type of weight-bearing loading subjected to the skeleton during horseback-riding was associated with differences in bone mass and muscle strength of the thigh, we investigated bone mass and isokinetic muscle strength in 20 female horse riders (age 17.9 +/- 0.6 years) who were riding 7.0 +/- 3.4 hours/week, and 20 nonactive females (age 17.8 +/- 1.1 years). The groups were matched according to age, weight, and height. Areal bone mineral density was measured in total body, head, lumbar spine, right femoral neck, Ward's triangle, and trochanter, the whole dominant and nondominant humerus, and in specific sites in the right femur diaphysis, distal femur, proximal tibia, and tibia diaphysis using dual X-ray absorptiometry. Isokinetic concentric and eccentric peak torque of the quadricep and hamstring muscles were measured using an isokinetic dynamometer. There were no significant differences in bone mass between the horseback riders and nonactives at any site measured. The horse riders were significantly (P < 0.05-0.01) stronger in concentric hamstrings strength at 90 degrees/second and 225 degrees/second and in eccentric quadricep and hamstring strength at 90 degrees/second. Horseback riding in young females is associated with a high muscle strength of the thigh, but not with a high bone mass.
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| 42. |
- Alfredson, Håkan, et al.
(författare)
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In situ microdialysis in tendon tissue : high levels of glutamate, but not prostaglandin E2 in chronic Achilles tendon pain
- 1999
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Ingår i: Knee Surgery, Sports Traumatology, Arthroscopy. - : Springer Science and Business Media LLC. - 0942-2056 .- 1433-7347. ; 7:6, s. 378-381
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Tidskriftsartikel (refereegranskat)abstract
- This investigation was to our knowledge the first to use the microdialysis technique to study concentrations of substances in a human tendon. In four patients (mean age 40.7 years) with a painful nodule in the Achilles tendon (chronic Achilles tendinosis) and in five controls (mean age 37.2 years) with normal Achilles tendons (confirmed by ultrasonography) the local concentrations of glutamate and prostaglandin E2 were measured under resting conditions. A standard microdialysis catheter was inserted into the Achilles tendon under local anesthesia. Sampling was performed every 15 min over a 4-h period. The results showed significantly higher concentrations of glutamate in tendons with tendinosis than in normal tendons (196 +/- 59 vs. 48 +/- 27 mumol/l, P < 0.05), and there were no significant changes in glutamate concentration over the period of investigation. There were no significant differences in the mean concentrations of prostaglandin E2 (83 +/- 22 vs. 54 +/- 24 pg/ml) between tendons with tendinosis and normal tendons. In conclusion, in situ microdialysis appears a useful method to study certain metabolic events in tendon tissue. The higher concentrations of the excitatory neurotransmitter glutamate in Achilles tendons with a painful nodule may possibly be involved in the pain mechanism in this chronic condition. Furthermore, there were no signs of inflammation in the tendons with painful nodules, as indicated by the normal prostaglandin E2 levels.
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| 43. |
- Alfredson, Håkan, et al.
(författare)
-
In vivo microdialysis and immunohistochemical analyses of tendon tissue demonstrated high amounts of free glutamate and glutamate NMDAR1 receptors, but no signs of inflammation, in Jumper's knee.
- 2001
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Ingår i: Journal of Orthopaedic Research. - 0736-0266 .- 1554-527X. ; 19:5, s. 881-886
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Tidskriftsartikel (refereegranskat)abstract
- This investigation describes, to our knowledge, the first experiment where the microdialysis technique was used to study certain metabolic events in human patellar tendons in combination with immunohistochemical analyses of tendon biopsies. In five patients (four men and one woman) with a long duration (range 12-36 months) of pain symptoms from Jumper's knee (localized tenderness in the patellar tendon verified as tendon changes with ultrasonography or MRI), and in five controls (four men and one woman) with normal patellar tendons, a standard microdialysis catheter was inserted into the patellar tendon under local anestesia. The local concentrations of glutamate (excitatory neurotransmitter) and prostaglandin E2 (PGE2) were registered under resting conditions. Samplings were done every 15 min during a 2 h period. In all individuals (patients and controls) biopsies were taken for immunohistochemical analyses. The results showed that it was possible to detect and measure the concentrations of glutamate and PGE2 in the patellar tendon with the use of microdialysis technique. There were significantly higher concentrations of free glutamate, but not PGE2, in tendons with tendinosis compared to normal tendons. In the biopsies, there were no inflammatory cell infiltrates, but, for the first time, it was shown that there was immunoreaction for the glutamate receptor NMDAR1 in association with nerve structures in human patellar tendons. These findings altogether indicate that glutamate might be involved in painful Jumper's knee, and further emphasizes that there is no chemical inflammation (normal PGE2 levels) in this chronic condition.
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| 44. |
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| 45. |
- Alfredson, Håkan, et al.
(författare)
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Intratendinous glutamate levels and eccentric training in chronic Achilles tendinosis : a prospective study using microdialysis technique.
- 2003
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Ingår i: Knee Surgery, Sports Traumatology, Arthroscopy. - : Springer Science and Business Media LLC. - 0942-2056 .- 1433-7347. ; 11:3, s. 196-199
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Tidskriftsartikel (refereegranskat)abstract
- Microdialysis has shown intratendinous glutamate levels to be significantly higher in Achilles tendons with painful tendinosis than in normal pain-free tendons, and treatment with eccentric training has shown good clinical results with diminished tendon pain during activity. In six patients with chronic painful Achilles tendinosis we performed microdialysis for 2 h, before and after the 12-week eccentric training program. The treatment was successful in all six patients, and the mean VAS score (amount of pain during Achilles tendon loading) decreased from 69 before treatment to 17 after treatment. There was no significant difference between the intratendinous glutamate levels before and after treatment. Our results offer no obvious neurophysiological explanation but showed that successful treatment with eccentric training was not associated with lowered intratendinous glutamate levels.
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| 46. |
- Alfredson, Håkan, et al.
(författare)
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Is There a Relationship Between Quadriceps Tendinopathy and Suprapatellar Plica? An Observational Case Series
- 2022
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Ingår i: International Medical Case Reports Journal. - : Dovepress. - 1179-142X. ; 15, s. 81-84
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Chronic painful quadriceps tendinopathy is a relatively rare condition known to be difficult to manage. Conservative management is first-line treatment and if that fails open intra-tendinous revision surgery followed by a long rehabilitation period is used. There is sparse research on etiology and new treatment methods. This observational study aimed to evaluate the intra-articular findings in patients with chronic painful quadriceps tendinopathy resistant to conservative management.Patients and Methods: Seven male athletes (mean age 33 years, range 22–40) suffering from chronic painful quadriceps tendinopathy in altogether 10 tendons, not responding to conservative management including heavy strength training, were included. Clinical examination and ultrasound scanning were used for diagnosis. Arthroscopy was used for evaluation of the inside of the knee.Results: In all 10 knees, there were obliterating major plica formations in the suprapatellar pouch.Conclusion: Obliterating plica formations in the suprapatellar pouch may be involved in the aetiology and pathology in quadriceps tendinopathy.
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| 47. |
- Alfredson, Håkan, et al.
(författare)
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Long-term loading and regional bone mass of the arm in female volleyball players
- 1998
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Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 62:4, s. 303-308
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, we compared the bone mineral content (BMC) and bone mineral density (BMD) in the arms of 11 female volleyball players (mean age 22.0 +/- 2.6 years) training for about 8 hours/week, and 11 nonactive females aged 24.6 +/- 3.1 years (mean +/- SD) not participating in regular or organized sport activity. Using dual X-ray absorptiometry (DXA), BMC was measured in the proximal and distal humerus, and BMD in the distal radius. Isokinetic concentric peak torque (highest value attained during 5 or 10 repetitions) of the rotator muscles of the shoulder and flexor and extensor muscles of the elbow were measured using an isokinetic dynamometer. The volleyball players had significantly higher BMC (P < 0.05) at the proximal humerus of the dominant arm compared with the nonactive group, but there were no differences between the groups in BMC of the distal humerus and BMD of the distal radius. In the volleyball players, BMC was significantly higher at the proximal humerus, at the distal humerus, and at the distal radius in the dominant compared with the nondominant arm. In the nonactive group, there were no significant differences in BMC and BMD between the dominant and nondominant arm at any site measured. Except for shoulder internal rotation strength and elbow flexion strength at 90 degrees/second that was higher in the dominant arm in the volleyball players, there were no significant differences in muscle strength of the rotator muscles of the shoulder and flexor and extensor muscles of the elbow between the dominant and nondominant arm in the volleyball players and nonactive controls. In the volleyball players, but not in the nonactive controls, there were several significant relationships between shoulder and elbow strength and BMC at the distal humerus of the dominant and especially the nondominant arm. These results show that young female volleyball players have a higher bone mass in the proximal humerus, distal humerus, and distal radius in the dominant compared with the nondominant arm, and a higher bone mass in the proximal humerus compared with nonactive controls. Muscle strength of the rotator muscles of the shoulder is not related to the higher bone mass in the proximal humerus of the dominant arm. Theoretically, the observed differences in bone mass can be related to the type of loading the skeleton undergoes when playing volleyball.
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| 48. |
- Alfredson, Håkan
(författare)
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Low recurrence rate after mini surgery outside the tendon combined with short rehabilitation in patients with midportion Achilles tendinopathy
- 2016
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Ingår i: Open Access Journal of Sports Medicine. - 1179-1543. ; 7, s. 51-54
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Tidskriftsartikel (refereegranskat)abstract
- Background: There is a general opinion that a structured and specific rehabilitation is needed after treatment of midportion Achilles tendinopathy to minimize recurrence of the condition. There is sparse knowledge about the recurrence rates in large patient materials after specific treatments for midportion Achilles tendinopathy.Aim: This study aimed to investigate the recurrence rates in a large number of patients with chronic painful midportion Achilles tendinopathy that had been surgically treated with the ultrasound (US) and Doppler (DP)-guided mini-surgical scraping technique. Postoperatively, a relatively simple rehabilitation protocol, including a range of movement exercises and gradually increased walking and biking before allowing free activity, was used.Materials and methods: From a database, information about the recurrence rates after US + DP-guided mini-surgical scraping, performed by a single surgeon on 519 tendons with US + DP-verified chronic painful midportion Achilles tendinopathy, was obtained.Results: Recurrence of painful midportion Achilles tendinopathy was found in 26 of 519 (5%) operated tendons, 13 from women and 13 from men. In 13 tendons, a close by located plantaris tendon was extirpated during the reoperation.Conclusion: In this large material on patients treated with US + DP-guided mini-surgical scraping for midportion Achilles tendinopathy, there were few recurrences, although only a simple and nonspecific rehabilitation protocol was used.
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| 49. |
- Alfredson, Håkan
(författare)
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Midportion Achilles tendinosis and the plantaris tendon
- 2011
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Ingår i: British Journal of Sports Medicine. - Loughborough : British Assoc. of Sport and Medicine. - 0306-3674 .- 1473-0480. ; 45:13, s. 1023-1025
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: When re-operating patients with midportion Achilles tendinosis, having had a poor effect of ultrasound (US) and Doppler-guided scraping, the author found the involvement of the plantaris tendon to be a likely reason for the poor result. The aim of this study was to investigate the occurrence of a plantaris tendon in close relation to the Achilles tendon in consecutive patients with midportion Achilles tendinosis undergoing treatment with US and Doppler-guided scraping. Material and methods: This study includes 73 consecutive tendons with chronic painful midportion Achilles tendinosis, where US+Doppler examination showed thickening, irregular tendon structure, hypo-echoic regions, and localised high blood flow outside and inside the ventral Achilles midportion. The tendons were treated with US+Doppler-guided scraping, via a medial incision. If there was a plantaris tendon located in close relation to the medial Achilles, it was extirpated. Results: An invaginated, or ‘close by located’, enlarged plantaris tendon was found in 58 of 73 (80%) tendons. Preliminary clinical results of the combined procedure, US + Doppler-guided surgical scraping and extirpation of the plantaris tendon, are very promising. Conclusions: A thickened plantaris tendon located in close relation to the medial Achilles seems common in patients with chronic painful midportion tendinosis. The role of the plantaris tendon in midportion Achilles tendinosis needs to be further evaluated and should be kept in mind when treating this condition.
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| 50. |
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