This study aims to develop and validate a predictive model for estimating the diameter of a quadrupled rectus femoris tendon graft used in anterior cruciate ligament (ACL) reconstruction. By analyzing patient anthropometric characteristics and intraoperative tendon measurements, we aim to identify reliable predictors of graft size to improve preoperative planning and surgical decision-making.

Graft diameter is a critical determinant of success in anterior cruciate ligament (ACL) reconstruction. Smaller graft sizes have been associated with increased failure rates. While predictive models exist for hamstring tendon grafts, no validated model currently exists for rectus femoris tendon grafts.

This study seeks to develop a predictive algorithm for estimating the diameter of a quadrupled rectus femoris graft using patient-specific anthropometric and tendon-related variables.

Data will be collected prospectively (or retrospectively if applicable) from patients undergoing ACL reconstruction using rectus femoris tendon autografts. Statistical modeling, including multivariate regression analysis, will be used to identify independent predictors and generate a predictive formula.

The study also aims to evaluate the diagnostic performance of the model in identifying clinically adequate graft sizes (≥8 mm or ≥9 mm).

Inclusion Criteria:

• Patients aged 18 years or older
• Undergoing primary ACL reconstruction
• Use of rectus femoris tendon autograft
• Availability of complete anthropometric and intraoperative data

Exclusion Criteria:

• Incomplete dataset

Patients undergoing ACL reconstruction with rectus femoris tendon autograft at a tertiary orthopedic center.