Summary

With a minimum of a 5-years and a maximum of 10-years follow up we report a low re-rupture rate and excellent clinical outcomes following the use of a hybrid (synthetic and autograft) graft for ACL reconstruction.

Abstract

Introduction

Anterior Cruciate Ligament Reconstruction (ACLR) surgery is a very common and established procedure which requires the use of a graft. Autograft is traditionally used, whether that be Hamstrings, Patella Tendon or Quadriceps Tendon, however its use involves an associated donor site morbidity. There is also potential concern regarding the potential inconsistencies in laxity of such a graft. To avoid such donor site morbidity Allograft has been used but there remain questions regarding the quality, strength, consistency and safety of allograft. Synthetic grafts have previously been used and poor results reported. However, not all synthetic grafts should be considered equal as all synthetic biomaterials will have different biomechanical and biomaterial properties and profiles when compared with one another. We report the results from use of a plasma treated, polyethylene terephthalate, synthetic cylindrical graft for ACLR.

Methods

Over a 5-year period, 127 patients underwent ACLR using a synthetic graft (Xiros-Neoligaments Jewel ACL, Leeds, United Kingdom). A single hamstrings tendon was harvested and positioned within the cylindrical synthetic graft to provide a hybrid graft. Anatomical femoral tunnel position was established through an anteromedial portal. The graft was fixed using suspensory fixation (Smith & Nephew Endobutton) on the femur and aperture fixation (Metal Interference screw) on the tibia. Each patient was followed up to a minimum of 5 years with a mean of 8.4 years (range 5 to 10 years). Patients were assessed for Pre-injury and post-operative Tegner Activity Level, IKDC Score, Lysholm Score and occurrence of re-rupture.

Results

The overall mean pre-injury Tegner Activity Level was 6.1 compared to the post-op level of 5.5 (p > 0.05). The mean IKDC Score was 91.7. The mean post-op Lysholm score was 94.2. Seven patients (5.5%) suffered a traumatic re-rupture of their ACLR, producing a survival rate of 94.5% at a minimum 5-years follow up. Following the traumatic ruptures those undergoing revision ACLR underwent arthroscopy and the findings did not suggest any evidence of significant synovitis within the knee. No direct correlation was observed between age of graft and risk of re-rupture.

Discussion

While autograft is commonly used as an established graft choice for ACLR, the use of a non-autograft would avoid donor site morbidity. Allograft remains an option but provides some difficulties of its own. Synthetic grafts have a great appeal due to their lack of donor site morbidity and consistently reliable biomechanical properties. Previous synthetic grafts have demonstrated poor results. We present excellent results with low re-rupture rates from the use of a specific synthetic graft in a hybrid technique when used with a single hamstring tendon. Further studies should be performed to determine the long-term effects of the use of this graft, including ten-year follow up. We would advocate a randomised controlled trial of its use to provide a true comparison to autograft.