Biomechanical Comparison of Proximal Hamstring Reconstruction Using Distal Hamstring Graft Versus Fascia Lata Graft for Treatment of Chronic Hamstring Injury.

BACKGROUND

Surgical reconstruction using autografts is often required in treating chronic proximal hamstring injuries where the hamstring has retracted >5 cm. There is a paucity of evidence that evaluates reconstructive procedures using the 2 most popular autografts, distal hamstring and fascia lata.

PURPOSE

To (1) compare failure load and elongation at failure between the proximal hamstring tendon reconstruction with distal hamstring and fascia lata grafts and (2) compare the stiffness between these reconstructions and the native state.

STUDY DESIGN

Controlled laboratory study.

METHODS

Seven pairs of human cadaveric hemipelvises (mean age, 60.4 ± 5.0 years; 6 male, 1 female) with no evidence of previous injury or abnormality were dissected to the proximal hamstring origin. Through use of a dynamic tensile testing system, each specimen underwent preconditioning followed by a distraction test to determine the native specimen stiffness. Each pair of specimens was assigned to undergo proximal hamstring reconstruction with distal hamstring and reconstruction with fascia lata. Each specimen then underwent preconditioning followed by pull to failure. The failure load, elongation at failure, mode of failure, and stiffness were determined for each repair.

RESULTS

The distal hamstring group exhibited a greater failure load (mean, 334 ± 108 N;

CONCLUSION

The distal hamstring group achieved higher failure load and stiffness than the fascia lata group, and stiffness of the distal hamstring group was not significantly different from that of the native tendon. Elongation at failure was not different between repair techniques. Although distal hamstring graft failure predominantly occurred in 3 distinct locations, failure of the fascia lata repair occurred predominantly at the tendon-graft interface. These cadaveric results suggest that it may be more clinically appropriate to use distal hamstring versus fascia lata for proximal hamstring reconstruction.

CLINICAL RELEVANCE

Our time-zero study suggests that the proximal hamstring reconstruction with distal hamstring could be the preferred surgical treatment for chronic hamstring injury over reconstruction with fascia lata. The failure load of reconstruction with distal hamstring was inferior to that of primary suture anchor, suggesting that rehabilitation after reconstruction should not be more aggressive than the standard postoperative rehabilitation protocol for acute repair.

Déclaration de conflit d'intérêts

One or more of the authors has declared the following potential conflict of interest or source of funding: S.U. has received consulting fees from Smith & Nephew and ConMed. M.J.P. has received royalties from Smith & Nephew Inc, Arthrosurface, Bledsoe, ConMed Linvatec, DJO, SLACK Inc, and Elsevier; has ownership/is a shareholder in Arthrosurface, MJP Innovations LLC, Vail Valley Surgery Center, and Vail MSO Holdings LLC; is a shareholder in MIS, EFFRx, Olatec, iBalance (Arthrex), Manna Tree Partners, Stryker, Trimble, 3M, Bristol Myers, Squibb, Pfizer, AbbVie, and Johnson & Johnson; has received support for education from Smith & Nephew Inc, ConMed Linvatec, Ossur, Arthrex, and Siemens Medical Solutions; has received speaking and consulting fees from Smith & Nephew Inc, MIS, Olatec, and NICE Recovery Systems; and has received hospitality payments from Siemens Medical Solutions and Synthes GmbH. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.