Summary

Double-bundle anatomic reconstruction for posteromedial ligament injury yield favorable functional outcomes and stability as assessed by valgus stress radiography is restored to within half millimeter compared to the native knee.

Abstract

Introduction

Isolated ligamentous injuries to the posteromedial structures of the knee, including the medial collateral ligament (MCL) and posterior oblique ligament (POL), can be managed conservatively in the vast majority of cases due to their propensity to heal. However, combined injuries or high grade tears which are not repaired early result in valgus instability. There are multiple described techniques of reconstructing these structures of which, the method described by LaPrade et al is based on strict adherence to anatomic landmarks. There is no published study which has independently verified the outcomes of this reconstruction other than by the designer surgeons. The aim was to assess the radiological and clinical outcome of double-bundle anatomic medial reconstruction when performed in isolation or combined with other ligament reconstructions.

Materials And Methods

This was a prospective study between April 2014 and June, 2017 which included patients with chronic (> 6 weeks old) posteromedial ligament injury with or without other ligament and meniscus lesions. Pre-operative valgus stress radiographs were taken as per a previously technique [2] and functional level was recorded as per the International Knee Documentation Committee (IKDC) and Tegner-Lysholm scores [3]. All patients underwent double-bundle posteromedial reconstruction with ipsilateral hamstring tendons by a single surgeon. The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) were reconstructed using bone-patella tendon-bone and central quadriceps tendon from the same knee. Simultaneous surgery for the meniscus was also performed as per the merits of the tear. All patients were followed up for a minimum of 12 months post surgery. Patients reported outcomes were collected in the form of IKDC and Tegner-Lysholm scores. Valgus stress radiographs were taken to calculate and compare the extent of medial knee joint opening.

Results

Thirty patients (20 males, 10 females) were enrolled with a mean age of 30.6±7.9 years. 2 patients had isolated medial sides lesions, 23 had an associated ACL while 5 ACL plus PCL tears. The mean follow up was for 27.2±9.7 months. The pre-operative valgus opening improved from 7.5±2.1 mm to 0.4±1.3 mm on stress radiographs. There were 19 patients who had a tighter medial side by 1.3±0.6 mm, while 11 patients were looser by 1.1±0.6 mm. The mean IKDC score improved from 58±8.5 to 77.6±9.7 (p<0.00001). The mean Tegner-Lysholm score improved from 62.3±11.8 to 87.6±7.8 (p<0.00001) with 12 excellent, 10 good and 8 fair outcomes. Three patients required manipulation for stiffness, 1 had superficial infection which was managed with oral antimicrobial therapy while 3 had persistent hypoesthesia suggestive of saphenous nerve injury. No patient had undergone a revision surgery till last follow up.

Conclusions

The results from our cohort suggest that double-bundle anatomic reconstruction for posteromedial ligament injury yield favorable functional outcomes. The stability as assessed by valgus stress radiography is restored to within half millimeter compared to the native knee. This is probably the first independent series to have validated the findings of the inventors of this technique.