The anatomy of the hip abductor muscles.

The anatomy of the hip abductors has not been comprehensively examined, yet is important to understanding function and pathology in the gluteal region. For example, pathology of the hip abductor muscle-tendon complexes can cause greater trochanteric pain syndrome, and may be associated with gluteal atrophy and fatty infiltration. The purpose of this study was to investigate the detailed morphology of gluteus medius (GMed), gluteus minimus (GMin), and tensor fascia lata (TFL), and determine whether the muscles comprised anatomical compartments. The gluteal region from 12 cadavers was dissected and data collected on attachment sites, volume, fascicular and tendinous anatomy, and innervation. Three sites of GMed origin were identified (gluteal fossa, gluteal aponeurosis, and posteroinferior edge of the iliac crest) and the distal tendon had lateral and posterior parts. GMed was the largest in volume (27.6 ± 11.6 cm(3); GMin 14.1 ± 11.1 cm(3); TFL 1.8 ± 0.8 cm(3)). Fascicles of GMin originated from the gluteal fossa, inserting onto the deep surface of its distal tendon and the hip joint capsule. TFL was encapsulated in the fascia lata, having no bony attachment. Primary innervation patterns varied for GMed, with three or four branches supplying different regions of muscle. Distinct secondary nerve branches entered four regions of GMin; no differential innervation was observed for TFL. On the basis of architectural parameters and innervation, GMed, and GMin each comprise of four compartments but TFL is a homogenous muscle. It is anticipated that these data will be useful for future clinical and functional studies of the hip abductors.

Hip abductor muscle volume in women with lateral hip pain: a case-controlled study.

UNLABELLED: Pathology of the hip abductor muscles and their associated tendons is implicated in the aetiology of lateral hip pain (LHP). Muscle atrophy is an important factor to consider in the diagnosis of this condition as it could result in reduced muscle volume and associated decreases in strength. PURPOSE: (1) To estimate the volumes of the gluteus medius (GMed), gluteus minimus (GMin) and tensor fascia lata (TFL) muscles, and (2) to examine pathological changes of the soft tissues in the vicinity of the hip joint, in women with and without LHP. METHODS: Twenty female participants (10 with LHP and 10 age-matched controls) underwent magnetic resonance imaging. Two radiologists reviewed the images for signs of pathological changes. Hip abductor muscle volumes were estimated using cross-sectional areas and Cavalieri's method. Differences in volume between sides, study groups and the three muscles were assessed. RESULTS: The volume of GMed was the largest (292.5 ± 33.3 cm3), followed by GMin (82.1 ± 12.1 cm3), then TFL (49.7 ± 18.9 cm3). No differences were evident in the volumes of the hip abductor muscles in individuals with LHP when compared to age- and sex-matched controls (GMed, p = 0.30; GMin, p = 0.40; TFL, p = 0.90). Pathology of the soft tissues was not specific to the symptomatic hips. CONCLUSIONS: Novel muscle volume data are presented for GMed, GMin and TFL in the context of LHP. Further research is needed to determine if symptom severity and duration have an impact on the extent of muscle atrophy in this population.