Bare area on the trochanter and its correlations to gluteal tendon insertion dimensions

Gluteus medius and minimus tears have recently been reported to be very common and the main etiology of lateral sided hip pain. The purpose of this study was to determine whether there is any correlation between the dimensions of the tendon insertions and bare areas (BA) and various bony landmarks. Twenty-seven hemipelvises from adult male hips were included. The bony landmarks [anterior tip (Ta), posterior tip of trochanter, vastus tubercle (VT) and center of BA] were marked. The longitudinal lengths and widths (maximum) of posterosuperior (PS), lateral facets (LF), minimus insertion (Min) and BA and the distance between posterior (Tp) and Ta and between anterior/posterior tips and the VT or center of BA were measured using a digital caliper. A correlation analysis was performed between variables. There was a correlation between LF_length and Min_length (r = 0.4, P = 0.01) and between Ta-BA and PS + LF (r = 0.5, P = 0.003) or Min_length (r = 0.4, P = 0.016). LF_width was negatively correlated with BA_width (r = -0.4, P = 0.002). Tp-BA was negatively correlated with BA_width (r = -0.4, P = 0.01). LF_width was correlated with Tp-BA, and this nearly reached statistical significance (r = 0.3, P = 0.05). BA can be used intraoperatively as landmarks to estimate the width of the LF and also to determine the length of the longitudinal insertion of the gluteus medius and minimus tendons.