Summary

A new surgical technique to repair lateral meniscus posterior root avulsions with the aisd of suture anchors is presented. It is technically feasible, reproducible and allows an anatomical repair of the LMPHA. The use of an all-suture anchor permits a faster surgical technique compared to the use of transosseous tunnels, avoiding the possible complications derived from their use.

Abstract

Introduction

Lateral Meniscus Posterior Horn Avulsion (LMPHA) is a relatively frequent injury that many times is found only at surgery. It has been described that it can happen in as much as 12% of ACL tears.
Until now, surgical procedures described to repair a LMPHA use transosseous tunnels. Initially, a proposal to use the ACL tibial tunnel for the posterior horn sutures was made, but it has been shown that pathologic biomechanical alterations derive from a misplacement of only 3 mm, and nowadays most repairs are done using independent tunnels with the aid of ACL guides. Unfortunately, those guides are cumbersome due to the anatomical relationship of the lateral femoral condyle to the lateral meniscus posterior horn footprint, and their use increases significantly the surgical time.
The use of arthroscopic anchors has been described for the repair of medial meniscus posterior horn avulsions, using a posteromedial portal, and it has been demonstrated that there are no significant biomechanical differences between the use of transosseous tunnels or anchors for the repair of the medial meniscus.
Until now, there are no published surgical techniques to reattach the LMPHA using arthroscopic anchors.
The purpose of this study is to present an all-arthroscopic technique to repair the lateral meniscus posterior root avulsions, avoiding the use of osseous tunnels and restoring the anatomical posterior horn footprint. To make it possible, we have used all-suture shoulder surgery anchors that allow the possibility of bending the guide pins, to reach areas not accessible to rigid implants.
MATERIAL AND METHODS: Four cadaver knees were used to optimize the surgical technique and test its feasibility. The posterior root of the lateral meniscus was elevated with an 11 blade scalpel, marking the footprint to check the accuracy of the repair, both before and after ACL resection, to evaluate the behavior of the guide pins in both situations. All-suture 1.4 mm JuggerKnot (Biomet, Warsaw. USA) implants were used. Those are implants frequently employed for instability repair in shoulder surgery, and they were placed with the help of the curved cannulas provided by the manufacturer.
Different access portals, cannula curves and flexible reamer were tested to evaluate the most effective configuration, and the possibility of placing two anchors in the posterior root footprint. Also, different arthroscopic portals were used, to test visualization, suture technique and suture management, and several suture configurations (simple, mattress and lasso-loop) were performed.

Results

The best access for anchor placement is obtained through a high parapatellar medial portal that allows the necessary obliquity to reach the lateral meniscus posterior horn footprint. Using an arthroscopic cannula is advisable. A spinal needle must be used to prepare a template to bend the curved guide before introducing it in the knee. The JuggerKnot curved guide allows bending to the angle required to reach the footprint without detrimental effects in the technique. The curved arthroscopic burr allows cruentation of the anatomical footprint. If surgeons decides so, it is possible to place two anchors in the anatomical footprint without difficulty. The use of 4 portals is advisable for a comfortable management of the anchor and the sutures, even when it is technically feasible to perform the procedure using only 3 portals. .

Conclusions

This new surgical technique is technically feasible, reproducible and allows an anatomical repair of the LMPHA. The use of an all-suture anchor permits a faster surgical technique compared to the use of transosseous tunnels, avoiding the possible complications derived from their use.