Patellar Tendon Length Change after Donor Tendon Repair in ACL Reconstruction

ABSTRACT

PURPOSE: Shortening of the patellar tendon after ACL reconstruction has been one of the causes of postoperative complieations such as anterior knee pain, patellar baja syndrome because of that reason, donor tendon defect was not closed generally. It took at least two years far the tendon to fill the gap by regenerated tendon tissue. But, sometimes protrusion of infra-patellar fat pad may prohibit the regenera-tion of patellar tendon, This study was designed to assess the amount of actual tendon shortening after tendon closure and complications because of it. MATERIALS AND METHODS: Thirty-two cases of arthroscopically assisted midthird patella tendon autograft ACL reconstruction were studied. Patella tendon defect was closed in all cases and the follow-up duration was more than 12 months. The patellar tendon length was measured before and after the defect site closure in operating room, Also, radiolagic tendon length changes were assessed using Insall-Salvati technique. RESULT: The mean patellar tendon length that had been measured in operating room was 51.5mm, 49.8mm (before and after the tendon defect closure). So, the mean shortening was 1.71mm(3.3%). The mean LT/LP ratio was 0.922, 0.894, 0.898(pre-operative and post-operative 6months, 12months). so, the radiologic mean shortening was 3.0%(6months), 2.6%(12months). There were only 4 cases of anterior knee pain and other complications were not found. CONCLUSION: Patellar tendon length change after donor tendon defect closure was about 3% and there were no complications associated with it.