Hip pain in three children accompanied by transient abnormal findings on MR images.

In a study of three children experiencing hip pain, low-signal-intensity patterns in the femoral head on T1-weighted magnetic resonance (MR) images eventually resolved, reverting to the normal signal patterns. These findings occurred in conjunction with documented clinical improvement of the patients' condition. T2-weighted images revealed isointense signals initially at the abnormal sites. Isointense signals prevailed on follow-up T2-weighted images. These MR imaging findings are likely due to transient bone marrow edema. These findings support the apparent sensitivity of MR imaging in the evaluation of marrow-based pathologic processes. Some pediatric patients with hip pain may have signs of transient bone marrow edema, rather than avascular necrosis, on MR images. Conservative management should be considered in such cases.