Muscle Size and Quality of the Gluteal Muscles and Tensor Fasciae Latae in Women with Greater Trochanteric Pain Syndrome.

Greater trochanteric pain syndrome (GTPS) is prevalent in women and severely impacts quality of life. A key muscle group demonstrating reduced strength are the hip abductors. An understanding of specific muscles affected will help guide targeted rehabilitation. Objectives of this case-control study were to compare gluteal and tensor fasciae latae (TFL) muscle size and quality (fatty infiltration) in women with symptomatic GTPS to asymptomatic age-matched female controls. Magnetic resonance imaging of 16 women with GTPS (mean age 55.75 years, range 23-69) and 15 asymptomatic controls (mean age 55.60 years, range 31-66) was undertaken. Muscle volumes of the gluteus maximus, gluteus medius, gluteus minimus, and TFL were calculated. Fatty infiltration was rated using the Goutallier classification system for all muscles in their entirety, as well as anterior and posterior segments of gluteus medius and minimus. Muscle volumes and fatty infiltration were compared between groups. Significantly smaller muscle volumes were identified in the symptomatic group for the upper (P = 0.01) and lower (P = 0.04) portions of gluteus maximus, gluteus medius (P = 0.03), and gluteus minimus (P = 0.02). There was no difference in TFL (P = 0.18). Symptomatic participants displayed significantly greater fatty infiltration in gluteus maximus upper (P = 0.021) and lower (P = 0.049) when adjusted for BMI, and gluteus minimus (P = 0.018), particularly in the posterior portion (P = 0.04). Anterior gluteus minimus demonstrated high amounts of fatty infiltration in both groups. Gluteal muscle atrophy and fatty infiltration in women with GTPS suggests gluteus maximus and minimus may be an important target for rehabilitation. Clin. Anat., 33:1082-1090, 2020. © 2019 Wiley Periodicals, Inc.