Abstract
Purpose of the study: Free patellar tendon plasty is the most common technique for repairing anterior knee laxity. Functional outcome can be compromised by invalidating knee pain. The purpose of this prospective randomized study was to compare the outcome of plasty procedures using hamstring tendon versus patellar tendon autografts.
Material and methods: From May 1998 through May 2001, 100 patients presenting an isolated grade I anterior cruciate ligament (ACL) tear were included. Exclusion criteria were: history of fracture, advanced-stage laxity (grade II or greater), and contralateral ACL tear. Randomization was performed in the operative theater using the closed envelop method. Two groups of 50 patients were designated: group A: arthroscopic free bone-tendon-bone patellar autograft; group B: arthroscopic free four-strand hamstring autograft. Two metallic interference screws were used for fixation in both groups. The two groups were comparable for demographic features and clinical, radiological, and instrumental laxity variables recorded before surgery. The position of the tunnels was noted according to Aglietti and was the same in the two groups. The same rehabilitation protocol in a dedicated center was used for both groups. All patients (none lost to follow-up) were assess using the IKDC 1993 criteria with objective instrumental measurement of residual laxity. The level of significance was set at 5%.
Results: There was no significant difference between the groups regarding: resumption of sports activity (level and delay), joint motion, ligament examination, the overall IKDC score, and radiological findings ate mean 40±13 months (range 13–69 months) follow-up. Pain at the harvesting site was observed in 34.78% of patients in group A at six months and in 39.5% of those in group B. Conversely, anterior pain was found in 8.5% of patients in group B at six months and 6.6% at one year (p< 0.05). This statistically significant difference disappeared at two years. Instrumental differential laxity was 0.57±1.3 mm in group A and 1.22±1.9 mm in group B (p=0.56, but with power < 80%). There were two cases of repeated traumatic tears in each group. Repeated meniscectomy was performed in one patient in group A and in three in group B (p=0.3074).
Conclusion: The results at 40 months follow-up of this prospective randomized study with no patients lost to follow-up confirmed the minimal morbidity observed at the harvesting site for hamstring plasty. There was no significant difference between the transplants (patellar tendon, hamstring). Anterior pain with the patellar tendon plasty attenuated after two years. Residual laxity was greater when using the hamstring method.
Correspondence should be addressed to SOFCOT, 56 rue Boissonade, 75014 Paris, France.
