Gender differences of muscle and crural fascia origins in relation to the occurrence of medial tibial stress syndrome.

Although women reportedly have a higher prevalence of medial tibial stress syndrome (MTSS) than men, the possible role of gender-based anatomical differences has not been investigated. The aim of the present study was to investigate the presence of gender-based differences in the range of muscle attachments along the entire medial tibia, the proportion of muscle attachment at the middle and distal thirds of the medial margin of the tibia, the structure of the crural fascia, and chiasm position. The specimens were 100 legs of 55 Japanese cadavers. Statistical analysis was carried out using a chi-square test to compare anatomical features between the sexes. The flexor digitorum longus (FDL) had a higher proportion of attachment to the middle and distal thirds of the medial margin of the tibia than the soleus (SOL; P < 0.001). The proportion of the SOL attachment to the middle and distal thirds of the medial margin of the tibia was 33.3% in men and 72.5% in women (P < 0.001). The soleal aponeurosis was not observed in any specimen. In all specimens the FDL formed the top layer of both chiasms. These results suggest that the higher prevalence of MTSS reported among women may be the result of gender-based anatomical differences.