Fracture of the lesser trochanter.

Isolated fracture or detachment of the lesser trochanter is an infrequent occurrence. In most cases the event is part of a complex of fractures involving the femoral neck and the greater trochanter. Isolated fracture caused by direct trauma is rare because of the anatomical location of the lesser trochanter which is protected anteriorly and posteriorly by large muscular masses, superiorly by the head and the neck of the femur, laterally by the femur itself, and medially by the ilio- and ischio-public branches of the pelvis. Trauma is usually indirect, caused by sudden traction by the iliopsoas muscle on the femoral tendinous insertion. The highest frequency is observed in young patients who are still growing where there is an imbalance between muscular strength and resistance of the osteochondral plate of the tendinous insertion. Particularly affected are adolescent athletes of male sex aged from 13 to 17 years. Similar overloading of traction in an adult would probably produce only muscular stretching. Diagnosis is based on radiographic ascertainment, obtained with the thigh in extra-rotation, supported by rather typical clinical findings such as acute pain in the inguinal region and in Scarpa's triangle, limping, passive movement of the hip in all directions with pain in maximum extension and relief when seated. Nonsurgical treatment with the limb resting in flexion, further confirmed by the case presented in this study, still remains the treatment of choice in most cases, obtaining excellent functional results. The authors believe that it was of interest to report this clinical case because of the rareness of the pathology observed and because of the specific features of its etiology.