Comparison between hamstring autograft and free tendon Achilles allograft: minimum 2-year follow-up after anterior cruciate ligament reconstruction using EndoButton and Intrafix

Abstract

Purpose: This study is to compare the clinical and radiographic results of anterior cruciate ligament (ACL) reconstruction with four-stranded autogenous hamstring tendon and two-stranded free tendon Achilles allograft fixed with EndoButton in the femoral tunnel and Intrafix in the tibial tunnel.

Materials and methods: 106 patients diagnosed with ACL rupture underwent ACL reconstruction. Autogenous hamstring tendon was used in 33 patients (group I) and free tendon Achilles allografts were used in 32 patients (group II). Median age was 23 years old (20-51) in group I and 22 years old (20-55) in group II. Range of motion, Lachman test, Pivot shift test, IKDC score, Lysholm score and side-to-side difference (SSD) were evaluated preoperatively and at the last follow-up. Tegner activity scale was evaluated before injury and at the last follow-up.

Results: The mean follow-up periods were 28.1 months in group I and 31.6 months in group II. Range of motion of the knee was not different from that of the unaffected side in most cases except one flexion deficit in group I and three in group II (n.s.). One in group I and three in group II showed grade two or three laxity on Lachman test at the last follow-up. One in group I and three in group II showed clear positive results on Pivot shift test at the last follow-up. Thirty in group I and 26 in group II were classified to IKDC A or B at the last follow-up (n.s.). Median Lysholm scores were 98 (85-100) in group I and 99 (85-100) in group II at the last follow-up (n.s.). Median Tegner activity scales were 6 (5-9) in group I and 6 (4-9) in group II at the last follow-up (n.s.). The mean SSD at the last follow-up were 1.4 ± 2.0 mm in group I and 1.9 ± 2.4 mm in group II (n.s.).

Conclusion: Clinical and radiological outcomes of ACL reconstruction with two-stranded free tendon Achilles allograft were comparable to those of four-stranded autogenous hamstring tendon. This technique is reasonable to accomplish good results without some weaknesses when using allograft with bone block.

Level of evidence: Therapeutic randomized controlled prospective study, Level I.