Vastus lateralis vs rectus femoris muscle flaps for recalcitrant hip joint infection: an anatomical study comparing the effectiveness of acetabular dead space control.
INTRODUCTION: Eliminating recalcitrant prosthetic hip joint infections remains one of the greatest challenges in orthopaedic surgery. In such cases, the salvage procedure of femoral head excision (the Girdlestone procedure) is often performed. There has been emerging surgical interest in filling the resulting acetabular dead space with a pedicled muscle flap, to enable antibiotic delivery. Both vastus lateralis and rectus femoris muscle flaps have been described for this purpose with good success. This study is the first anatomical investigation comparing vastus lateralis and rectus femoris as candidates for interposition myoplasty following hip joint excision. METHODS: Following standard surgical technique, the Girdlestone procedure and interposition myoplasty of both rectus femoris and vastus lateralis were performed on 10 cadavers. The primary aim was to determine which muscle flap eliminated a greater volume of acetabular dead space. Secondary aims were to characterize the blood supply to rectus femoris and assess additional metrics indicative of the likelihood of flap success. RESULTS: The vastus lateralis flap eliminated more dead space than rectus femoris. However, the use of the rectus femoris flap was feasible in all cases and has several benefits, including ease of harvest, mobility and aesthetics. The location of the inferior vascular pedicle into rectus femoris was relatively consistent and the most effective predictor of flap success. CONCLUSION: Both vastus lateralis and rectus femoris are effective in reducing acetabular dead space. While vastus lateralis can fill a greater volume, the rectus femoris flap has technical advantages, related to the predictability of the blood supply.