Isolated hamstring tendon autograft should be avoided in high-risk patients undergoing anterior cruciate ligament reconstruction

Aims: Younger patients are at the highest risk of repeat injury after anterior cruciate ligament (ACL) reconstruction. The hamstring tendon autograft remains the most popular choice of graft in the world, but its use in these high-risk patients is controversial. The aim of this study was to compare revision rates between the bone-patellar tendon-bone (BTB) and hamstring tendon autografts in a high-risk patient population. Methods: Prospective data recorded in the New Zealand ACL Registry were analyzed. Primary ACL reconstructions performed between April 2014 and March 2022 were included, allowing for a minimum follow-up of two years. High-risk patients were analyzed using the following criteria: age between 14 and 25 years, ACL rupture during sporting activity, time from injury to surgery within 12 months, grade 2 pivot shift, and a minimum preinjury Marx activity score of 8. The rate of revision was compared between the BTB and hamstring tendon autografts using a univariate chi-squared test and multivariable Cox regression survival analysis to calculate hazard ratios (HRs) with 95% CIs. Results: A total of 3,482 high-risk primary ACL reconstructions were analyzed. A lateral extra-articular procedure was performed in 175 cases with no revisions performed during the study period. The rate of revision was 11.4% (238/2,091) with the hamstring tendon autograft versus 4.3% (60/1,391) with the BTB autograft (p < 0.001). The hamstring tendon autograft had a 2.5-times higher risk of revision compared with the BTB autograft (adjusted HR 2.5 (95% CI 1.9 to 3.3); p < 0.001). The number needed to treat with a BTB autograft to prevent one revision was 14 patients. Conclusion: Isolated hamstring tendon autograft has a high rate of revision and should be avoided in high-risk patients undergoing ACL reconstruction.