Predictive value of preoperative gluteus and iliacus muscle volumes for patient-reported outcomes following total hip replacement: a three-dimensional volumetric analysis.

INTRODUCTION

This study aimed to investigate the relationship between hip muscle mass and patient-reported outcomes (PROs) after total hip arthroplasty (THA) surgery for hip disease using 3D volumetric measurements of the gluteus muscle group and iliac muscle.

MATERIALS AND METHODS

Between January 2020 and December 2021, 85 patients who had undergone unilateral THA for osteoarthritis or osteonecrosis of the femoral head were enrolled. Using a 3D modeler program, automatically generated 3D reconstructed images of the hip muscles were obtained, and volumetric measurements were performed. Both unadjusted and height (m)-adjusted muscle volumes of the gluteus maximus (unadjusted volume: GmaxV; adjusted volume: GmaxI), gluteus medius (unadjusted volume: GmedV; adjusted volume: GmedI), gluteus minimus (unadjusted volume: GminV; adjusted volume: GminI), and iliacus (unadjusted volume: IliacV; adjusted volume: IliacI) muscles were measured on the affected side and both sides. Pearson correlation analysis between muscle volumes and postoperative 12-month PROs were performed.

RESULTS

The preoperative Gmax volume on the affected side was significantly associated with post-operative PROs, especially mHHS (GmaxV:  = 0.026; GmaxI:  = 0.005) and UCLA scores (GmaxV:  = 0.006; GmaxI:  = 0.002). For measurements on both sides, Gmed volume was the sole index showing a significant correlation with postoperative UCLA scores (GmedV:  = 0.023; GmedI:  = 0.043).

CONCLUSIONS

The current study suggests that preoperative gluteus muscle volume may have predictive value for postoperative PROs of hip disease patients who have undergone THA surgery.