Long-term follow-up of posttraumatic marrow edema of the knee

This paper defines the long-term course of patients in whom posttraumatic marrow edema (PTME) is noted both with and without associated findings. The MR studies of 41 patients (11 female, 30 male, aged 14--78 years) were reviewed, and the findings were correlated with subsequent therapy and long-term results. All patients were followed-up for at least 6 months. Ten patients had isolated marrow edema, defined as low-signal regions on T1-weighted images that became high-signal regions on T2-weighted images. Sixteen had associated minuscule injuries (usually in the compartment opposite the PTME), 12 had recognizable fractures (low-signal lines associated with the edema pattern), and 10 had cruciate injuries