SUCCESSIVE USE OF THE PATELLAR LIGAMENT FOR RECONSTRUCTION OF THE ANTERIOR CRUCIATE LIGAMENT: 19 CASES

Abstract

Purpose: The difficulty of successive reconstructions of the anterior cruciate ligament (ACL) using an autologous graft depends on many factors. The choice of the new transplant is crucial. The purpose of this study was to assess outcome in 17 patients who underwent successive repairs of the ACL after failed patellar tendon graft where the same patellar ligament site was used to harvest the graft. This choice resulted from the width of the existing bone tunnels (irrespective of the type of screw used) that were often correctly positioned by contraindicated a relatively narrow transplant.

Material and method: The graft was obtained from the patellar ligament at the same site as used for the primary repair in 19 patients. The graft was medialised so half of the fibres were cicatricial and half were tendon with bone prolongations. Arthroscopy revealed a lesion of the distal portion of the transplant near the tibial inertion in nine cases, a proximal lesion in five cases and distension in five cases. Five patients had also had a contralateral plasty of the ACL. Mean age was 31 years. Symptoms included instability, alone or with pain. In 12 cases, partial meniscectomy was performed before or during the repeat plasty procedure. Minimum follow-up was one year for 17 patients with a mean of 21 months. IKCD and Lysholm-Tegner criteria were assessed. Laxity was measured at maximal manual traction using a KT 1000.

Results: Overall IKDC outcome was 2A, 10B, 4C, and 1D. Differential laxity at maximal manual traction, evaluated for the 12 patients with a healthy contralateral knee was 2.7 ± 1.3 mm (versus 1.7±1.9 mm in the control series). Mean pre-postoperative gain in the 17 patients was 5.4 ± 3 mm (versus 5.6 ± 2.4 mm in the control series). The predominant sign was residual pain (11/17). Pain was generally moderate and induced by exercise. Pain at the site of graft harvesting was frequent during the six months after surgery (11 cases) but rare after one year (2 cases).

Discussion: Due to the cartilage and meniscal history of this population of patients who had undergone several repairs of the ACL, the results were satisfactory and little different from those obtained with the same primary procedure in a control group. The residual laxity study showed that the mechanical quality of the transplant was good. Histology studies published on repeat patellar tendon harvesting have been discordant.

Conclusions: Repeat harvesting of the patellar tendon for ACL repair appears to be an excellent alternative since it is thicker than the primary transplant and thus fills the bone defects better than other transplants (particularly hamstring).