OBJECTIVE: To compare the morphologic, histochemical, and immunohistochemical characteristics of the tendons of the semitendinosus and the gracilis muscles to be used as autograft in anterior cruciate ligament reconstruction surgeries in men and in women. METHODS: Tendon samples of the semitendinosus and gracilis muscles of 36 patients (36 knees) were evaluated. Ages ranged from 15 to 46 years, with a mean of 29.3 years. Regarding color, 33 patients were caucasian, and three were non-caucasian. Regarding the sid, 23 knees were right knees, and 13 were left knees. Patients were divided into two groups: men (n = 20) and women (n = 16). Tendon samples were submitted to histological, histochemical, and immunohistochemical analyses. RESULTS: No statistically significant differences were seen with respect to age, race, side, inflammatory process, vascularization, and alcioanophilia between the groups under evaluation. There was increased cellularity of semitendinosus muscle tendons when compared to gracilis muscle tendons (males p = 0.03, and females p = 0.22). The authors could observe that women show a trend to greater presence of calcifications in the tendons of the semitendinosus and the gracilis muscles (p = 0.06 and p = 0.09), and to increased degeneration of the collagen fibers of the semitendinosus muscle tendons (p = 0.06). Regarding the presence of estrogen receptors in the tendons of semitendinosus and gracilis muscles, they observed an increased number of receptors in male patients. CONCLUSION: The different genders showed morphologic, histochemical, and immunohistochemical differences in the tendons of the semitendinosus between the tendons of the gracilis and semitendinosus muscles in the male gender.
Anterior cruciate ligament; Tendons; Immunohistochemistry; Comparative study
