Patellar tendon versus quadrupled bone-semitendinosus anterior cruciate ligament reconstruction: a prospective clinical investigation in athletes

Abstract

Purpose: Patellar tendon and hamstrings are both used in anterior cruciate ligament (ACL) reconstruction, and comparisons have been reported with different results. The purpose of this clinical study was to compare the results of ACL reconstruction in athletes with 2 different graft types, both using bone-to-bone healing: bone-patellar tendon-bone graft and a quadrupled bone-semitendinosus graft. Type of Study: Outcomes study. Methods: From 1994 to 1997, 2 groups of 40 athletes who underwent ACL replacement with patellar tendon and quadrupled bone-semitendinosus grafts were prospectively evaluated. Preinjury activity level, age, and gender were comparable in both groups. All patients were operated on by the same surgeon within 5 months from injury and underwent group-specific rehabilitation programs. An independent examiner performed the final evaluations at 36 months. Review included clinical examination, radiographs, computed analysis, isokinetic and functional strength tests, and subjective and objective evaluation with standard knee scores. Additional procedures were recorded. Statistical analysis was performed with both parametric and nonparametric tests. Results: Average surgical time was longer with the semitendinosus graft, and postoperative pain was higher in the patellar tendon group. Standard knee evaluation scores and subjective assessment revealed no significant differences. Isokinetic testing of flexion-extension and internal-external rotation showed lower quadriceps strength and a mild deficit of external rotation in the patellar tendon group and slightly lower flexor strength in the semitendinosus group at 12 months. Computerized laxity analysis showed no difference between the 2 groups with 90% of patients having less than 3 mm side-to-side difference, with a gender difference in the semitendinosus group. Kneeling pain was higher in patellar tendon group. Conclusions: The bone-patellar tendon-bone and quadrupled bone-semitendinosus autograft provide excellent grafts for ACL reconstruction. Both techniques are comparable regarding final stability, but in patients with extensor mechanism problems or those who engage in sports with a high incidence of patellar tendonitis, the semitendinosus graft should be considered.