[Temporomandibular joint arthropathy in situ steroid injection].

INTRODUCTION: Temporomandibular disorders (TMDs) affect the masticatory muscles and the temporomandibular joints (TMJs). TMDs most often result from occlusal and/or muscular disorders and are then called primary or idiopathic TMDs. Less frequently, TMDs are related to local (trauma, infection) or general (rheumatoid arthritis) causes and are then called secondary TMDs. A little known iatrogenic cause of secondary TDM is the osteoarthritis that may be induced by intra-articular cortisone injections. We report one case of condylar lysis that occurred after one single intra-articular cortisone injection. OBSERVATION: A 62-years-old woman consulted for a long-lasting TMD on the left side manifesting itself through pain and noise. She benefited one year before from an intra-articular injection of cortisone by her rheumatologist for repeated closed lock of her left TMJ. Physical examination showed limited mouth opening with deviation on the left side. Lateral movements on the right side were impossible. The panoramic X-ray showed a condylar lysis on the left side that was on the CT scan. MRI additionally showed an anteriorly displaced and severely reshaped disc and an articular inflammation without intra-articular effusion. DISCUSSION: TMJ osteoarthritis secondary to unique or repeated intra-articular steroid injections are little-known. They are clinically expressed as typical TMDs and characterized on X-rays by condylar lysis and inflammation. Intra-articular injections of steroids are not totally harmless and other treatments must be preferred.