Ultrasound examination of soft tissue injury of the lower limb in athletes.

We performed ultrasonography on 32 athletes complaining of intense pain in a swollen and tender thigh or calf after a contusion or stretching trauma. The ultrasonogram was used to visualize the presence and size of a suspected hematoma. The findings included the following: 7 patients with a circumscribed, anechoic lesion compatible with a liquefied hematoma; 10 patients with a circumscribed lesion of mixed echogenicity compatible with areas of liquefied hematoma, coagulated blood, and edema; and 15 patients with a diffuse change in echogenicity of the whole muscle. The circumscribed liquefied, and mixed hematoma were more common after contusion trauma, while the diffuse type was more common after injury caused by stretching. Ultrasonography is useful in localizing the hematoma and in characterizing the different types. Differentiation is important in diagnosis and choice of treatment.