[MRI-based measurement of muscle damage after minimally invasive hip arthroplasty].

Muscle trauma in minimally invasive hip arthroplasty using a direct anterior approach was assessed by magnetic resonance imaging (MRI) in 25 patients preoperatively, as well as 6 months after total hip replacement. The MRI evaluation included the measurement of changes in muscle cross-sectional area (CSA = atrophy) and fatty infiltration of the muscles. Using MRI, preoperatively existing and operatively caused muscle tissue damage could be detected by assessing changes in muscle CSA and fatty infiltration. Even preoperatively, a muscular atrophy and fatty infiltration could be demonstrated in the diseased hip. Using the minimally invasive direct anterior approach, a postoperative significantly reduced CSA and significantly increased fatty degeneration was detected for the M. tensor fasciae latae and the M. glutaeus minimus. No increased damage of the M. glutaeus medius could be detected.