Podium (Sports) 11

Predictor Variables of Hamstring Tendon Diameter and the Influence of Hamstring Tendon Graft Diameter in Patient

Ted Matthew P. Evangelista, MD; Alberto Ma. V. Molano, MD, MHPEd, FPOA; Jeremy James C. Munji, MD, FPOA; Carmelo L. Braganza, MD, FPOA UST

Background: With increasing participation in organized sports among the younger population, more anterior cruciate ligament (ACL) injuries are being recognized. In our institution, the ACL is the most frequently reconstructed ligament among young athletes. However, there is paucity of data in the literature on the predictive variables of autologous hamstring tendon graft diameter as well as the influence of hamstring graft diameter in patient reported outcomes among the young, competitive athletes.

Objective: To identify the factors associated with hamstring tendon diameter and to determine the association of graft size diameter in patient reported outcomes among young athletes

Study design: Historical cohort study

Methods: Thirty-five (35) young competitive athletes that underwent arthroscopic ACL reconstruction using hamstring tendon autograft at our institution for complete ACL injury between January 2019 and January 2020 were identified from our computer database and archive of records. Information such as demographic data, anthropometric parameters, operative technique, and patient-related outcomes pre-operatively and at 1-year follow-up were likewise extracted from our database and archive of records.

Results: The mean age of study was 20.63 years old (SD=2.26). The mean graft diameter size among athletes was 8.29 mm (SD=0.91). Regression analysis showed that age (β=0.35, p=0.042), weight (β=0.48, p=0.004), height (β=0.62, p=0.0001), and pre-injury Tegner score (β=0.44, p=0.008) are significantly associated with graft size diameter. However, graft size diameter did not significantly influence return to previous activity level and other one-year post-operative patient-reported outcomes.

Conclusion: Pre-injury activity level, age, and anthropometric parameters (weight and height) are predictive factors of autologous hamstring tendon graft size diameter among young Asian athletes. The harvested hamstring tendon graft diameter did not influence the patient’s return to previous activity level and other patient reported outcomes at one year after arthroscopic ACL reconstruction. These findings support smaller hamstring grafts in Asians, suggesting grafts of less than 8 mm may be acceptable in this population.

Keywords: ACL reconstruction, hamstring autograft, graft size