Harvesting hamstring tendons for ACL reconstruction influences postoperative hamstring muscle performance.
ABSTRACT Anterior cruciate ligament (ACL) reconstruction using hamstring tendons has recently received attention because of less donor site morbidity. It has been reported that harvesting hamstring tendons has little effect on postoperative hamstring muscle performance based on the peak torque value of the hamstring strength. However, recent studies have clarified some adverse effects of harvesting hamstring tendons. There is still argument about the influences of harvesting hamstring tendons on postoperative hamstring muscle performance. The purpose of this study was to evaluate the postoperative hamstring muscle performance measured by various parameters after harvesting hamstring tendons for ACL reconstruction.
We evaluated the postoperative hamstring muscle performance after harvesting hamstring tendons in 58 patients who underwent ACL reconstruction. We assessed peak torque value, total work, and peak torque angle in the isokinetic hamstring strength test and active knee flexion angle. We classified the patients into three groups according to the type of hamstring used for ACL reconstruction: 1) the autologous semitendinosus tendon (ST); 2) the autologous ST and the gracilis tendon, which were harvested from the ipsilateral knees; and 3) allogeneic fascia lata.
This study clearly demonstrated that the peak torque value and total work in the patients in each group compared to preoperative normal knees were not statistically different; however, the more hamstring tendons were harvested, the more loss of active knee flexion angle was observed and the more the peak torque angle was shifted to a shallow angle, suggesting that the hamstring strength might be weaker at the deep flexion angle.
Physicians should recognize that the ACL reconstruction using autologous hamstring tendons is not appropriate for sportsmen or women who are required to flex their knees deeply or powerfully in their performance.
Article: Correlation between Hamstring Flexor Power Restoration and Functional Performance Test: 2-Year Follow-Up after ACL Reconstruction Using Hamstring Autograft.[show abstract] [hide abstract]
ABSTRACT: To evaluate the restoration of the flexor power and the correlation between the flexor power and functional performance tests (FPTs) after anterior cruciate ligament (ACL) reconstruction with hamstring autograft. Twenty-three men, who underwent ACL reconstruction with hamstring autograft, were evaluated using Lysholm, Subjective IKDC, Tegner activity score, isokinetic flexion and hyperflexion power test, and the FPTs at 1 and 2-year follow-up. We analyzed the mean change from 1 to 2 year and the correlation between both the flexion and hyperflexion power deficit with the FPTs at each follow-up. Mean age of the patients was 30.9 years (range, 19 to 44). Tegner activity score was significantly increased from 5.7 to 6.3 (p=.010). Hyperflexion power of the involved knee deficits significantly decreased at 2 year follow-up compared with 1 year (p<.001). There was a correlation between the flexor power deficit and the co-contraction, carioca, and involved one-legged hop test at each follow-up. However, no significant correlations were revealed between the hyperflexion power deficit and the FPTs. Hyperflexion power deficit after ACL reconstruction with the hamstring autograft decreased at 2 year follow-up compared to 1 year and does not affect the results of the FPTs.Knee surgery & related research. 06/2012; 24(2):113-9.
Article: Hamstring strength recovery after hamstring tendon harvest for anterior cruciate ligament reconstruction: a comparison between graft types.[show abstract] [hide abstract]
ABSTRACT: The purpose of this study was to investigate hamstring strength after harvest of 1 or 2 hamstring tendons for anterior cruciate ligament reconstruction. We recruited 50 individuals who had returned to regular sporting activity to participate in a comparative study at a mean of 32.5 months after anterior cruciate ligament reconstructive surgery (30 in semitendinosus-gracilis group and 20 in semitendinosus group). Isokinetic hamstring strength (at 60 degrees/s and 180 degrees/s with the peak torque and torque produced at 60 degrees, 90 degrees, and 105 degrees of knee flexion recorded) and isometric hamstring strength (at 30 degrees, 90 degrees, and 105 degrees of knee flexion) were measured, and the standing knee flexion angle was used to evaluate functional hamstring strength recovery. No significant differences between the groups were found in any of the isometric or isokinetic strength measures or in the standing knee flexion angle. No relation was found between the standing knee flexion angle and the isometric hamstring strength results obtained at 105 degrees of knee flexion (r(2) = 0.034). These findings show that the choice of hamstring tendon graft-that is, semitendinosus alone or semitendinosus and gracilis-is unlikely to significantly influence postoperative hamstring strength outcomes in athletes returning to sports postoperatively. Both graft choices showed strength deficits of between 3% and 27% compared with the nonoperated limb, indicating that hamstring strength deficits persist despite successful completion of rehabilitation. The results also show that the standing knee flexion angle should not be used as a surrogate clinical measure of hamstring strength. Level III, retrospective comparative study.Arthroscopy The Journal of Arthroscopic and Related Surgery 04/2010; 26(4):462-9. · 3.02 Impact Factor
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ABSTRACT: The tissue engineering field has made great strides in understanding how different aspects of tissue engineered constructs (TECs) and the culture process affect final tendon repair. However, there remain significant challenges in developing strategies that will lead to a clinically effective and commercially successful product. In an effort to increase repair quality, a better understanding of normal development, and how it differs from adult tendon healing, may provide strategies to improve tissue engineering. As tendon tissue engineering continues to improve, the field needs to employ more clinically relevant models of tendon injury such as degenerative tendons. We need to translate successes to larger animal models to begin exploring the clinical implications of our treatments. By advancing the models used to validate our TECs, we can help convince our toughest customer, the surgeon, that our products will be clinically efficacious. As we address these challenges in musculoskeletal tissue engineering, the field still needs to address the commercialization of products developed in the laboratory. TEC commercialization faces numerous challenges because each injury and patient is unique. This review aims to provide tissue engineers with a summary of important issues related to engineering tendon repairs and potential strategies for producing clinically successful products.Journal of musculoskeletal & neuronal interactions 06/2011; 11(2):163-73. · 2.00 Impact Factor