Prediction of the quadruple hamstring autograft thickness in ACL reconstruction using anthropometric measures

Objective: The aim of this study was to determine whether simple anthropometric measurements, such as height, weight, body mass index (BMI), age, and thigh circumference can be used to accurately predict the diameter of hamstring tendons for anterior cruciate ligament (ACL) reconstruction surgery. Methods: One hundred sixty-four consecutive male patients who underwent ACL reconstruction using quadruple hamstring autograft between January 2010 and December 2011 were prospectively evaluated. Anthropometric measurements including height, weight, BMI, age and thigh circumference were recorded preoperatively. The thickness of the quadruple hamstring autograft was intraoperatively determined using sizing cylinders. Correlation coefficients (Pearson’s r) and stepwise, multiple linear regression were used to determine the relationship between the outcome variable (hamstring graft diameter) and the predictor variables (age, height, weight, BMI, thigh circumference). Results: Correlation analysis revealed a positive relation between the height, weight and graft thickness (p=0.000 and p=0.002, respectively). Taller and heavier patients tended to have thicker quadrupled hamstring graft. However, age, thigh circumference, and BMI did not correlate with the graft thickness (p=0.700, p=0.290 and p=0.727, respectively). Stepwise, multiple linear regression indicated that height was statistically important as a predictor for hamstring graft diameter (R2=0.157, p=0.0001) and yielded the following regression equation for predicting quadrupled hamstring graft thickness: graft thickness = [(height in cm) ¥ 0.052) - 1.07] mm. Conclusion: Height can be used as a practical and accurate measurement to preoperatively predict quadruple hamstring graft diameter in male patients. Identification of possible hamstring tendon autograft insufficiency allows for preoperative determination of additional graft source possibilities, resulting in a more prompt surgical strategy.