Predictive Value of Preoperative 3‐Dimensional Computer Tomography Measurement of Semitendinosus Tendon Harvested for Anterior Cruciate Ligament Reconstruction

PURPOSE: The aim of this study was to evaluate preoperative measurement of the semitendinosus tendon (ST) by 3-dimensional computed tomography (3-D CT), before using ST as the substitute in the anterior cruciate ligament (ACL) reconstruction. TYPE OF STUDY: Cross-sectional study to compare anatomic findings with clinical findings. METHODS: The study involved 28 patients who underwent ACL reconstruction using autogenous ST graft. Preoperative 3-D CT images of ST were obtained with a multidetector-row CT scanner, and rendered qualitatively by the volume-rendering technique. The length and cross-sectional area of ST measured with 3-D CT were compared with the length of the harvested ST and the cross-sectional area of the grafted quadrupled tendon. RESULTS: The total length of ST measured with 3-D CT ranged from 220.3 to 285.4 mm, with a mean (+/- SD) of 248.0 +/- 17.1 mm, and that measured at surgery ranged from 230.0 to 290.0 mm, with a mean of 257.1 +/- 16.5 mm. These 2 values showed a close positive correlation (gamma = 0.634, P = .002). The cross-sectional area of ST measured with 3-D CT ranged from 4.29 to 18.5 mm2 with a mean of 11.9 +/- 4.6 mm2, and that of the substitute measured at surgery ranged from 28.3 to 56.7 mm2 with a mean of 45.5 +/- 6.9 mm2). There was no significant correlation between the areas of ST measured by CT and the areas of ST measured during surgery. CONCLUSIONS: Preoperative 3-D CT imaging predicts the length of ST. These findings support the measurement of ST length by 3-D CT as a useful tool for planning ACL reconstructive surgery and for providing important preoperative information to patients. LEVEL OF EVIDENCE: Level III, diagnostic study.