Secondary Osteonecrosis of Both Tibial and Femoral Condyles Induced by Dexamethasone Overuse: A Case Report.

Osteonecrosis of the knee is a rare but serious condition that can lead to progressive joint destruction and functional impairment. Secondary osteonecrosis, particularly related to corticosteroid overuse, represents a challenging and often under-recognized clinical entity. We report the case of a 32-year-old female from Eastern Morocco who developed severe bilateral knee osteonecrosis involving both the distal femur and proximal tibia following prolonged self-medication with high-dose dexamethasone. The patient presented with chronic knee pain, stiffness, and functional limitation. Imaging studies, including magnetic resonance imaging, revealed characteristic osteonecrotic lesions with a serpiginous border and the double line sign in both the femoral and tibial components. Laboratory investigations excluded infectious, inflammatory, and hematologic causes. Given the extensive osteonecrotic damage and the patient's refusal of surgical intervention, a conservative management strategy combining physical rehabilitation, lifestyle modification, protected weight-bearing, and analgesia was adopted. This case highlights the devastating potential of unsupervised corticosteroid use and emphasizes the importance of early recognition, comprehensive patient history, and timely imaging to prevent severe joint degeneration. To our knowledge, this is the first reported case in Eastern Morocco with such extensive topographic involvement secondary to dexamethasone overuse, contributing valuable insight to the literature on corticosteroid-induced musculoskeletal complications.