Sex differences in the functional status of the lower extremities in patients with chronic osteomyelitis and in persons under cyclic load

Aim. The paper aims to investigate sex-related structural and strength differences between lower leg and thigh muscles in patients with chronic osteomyelitis and in persons involved in regular physical activity. Material and methods. Patients with chronic osteomyelitis and young male sprinters (n = 10), male (n = 10) and female (n = 10) middle-distance runners and apparently healthy volunteers of the same age not involved in regular physical activity (n = 12) were examined. The structure and the maximum moment of thigh muscles, foot plantarflexor (PF) and dorsiflexor (DF) muscles were measured. Measurements were performed with a custom-made dynamometer of the Ilizarov Medical Research Center. The contractile activity of muscles was assessed by ultrasound sonography. Results. In patients with chronic inflammation of lower limb segments, pronounced changes in the structure of lower leg muscles were found. Muscle strength was significantly reduced, no sex differences in the structure and strength of lower leg muscles were observed. However, in middle-distance runners, sex differences were found in terms of the maximum moment of PF muscles. Female athletes showed the following values of the maximum moment of PF muscles: 171.2 ± 7.0 N • m (right leg), 169 ± 8.1 N • m (left leg), which was lower by 15.7 % and 19.6 % (p ≤ 0.05) compared to male athletes. No statistical differences were observed between male and female middle-distance runners in terms of the maximum moment of DF muscles. The relative moment of DF muscles was significantly reduced in male middle-distance runners compared to female athletes, whose results were 14.5% (right) and 9.5% (left) higher. In contrast, the relative values of PF muscles were higher in male middle-distance runners. In male sprinters and middle-distance runners, the moment of lower leg extensor muscles was higher than that of female athletes (р ≤ 0.05). In male sprinters and middle-distance runners, the contractile activity of lower leg flexor muscles was higher than that of female athletes by 32 % (right) and 34.8 % (left) (р ≤ 0.01). Conclusion. The results obtained can be used in the rehabilitation and treatment of patients with musculoskeletal pathology, as well as in sports medicine and science.