Osteonecrosis-like syndrome of the medial tibial plateau.

Thirty-six patients with an osteonecrosis-like lesion of the proximal tibia presented due to the sudden onset of pain along the medial side of the knee and marked tenderness over the medial tibial plateau. Initially, the roentgenograms were within normal limits or showed mild degenerative joint changes. All patients had positive radionuclide bone scans; the lateral view clearly demonstrated the lesion within the tibia. The symptoms remained severe for six to 12 weeks, after which they gradually resolved. Most patients were asymptomatic after nine to 12 months. Differentiating this entity from a torn meniscus or pes anserinus bursitis is difficult without obtaining a bone scan. As more bone scans are obtained, this may prove to be a common entity; recognition of the condition may prevent unnecessary surgery.