[Chronic hydarthrosis of the knee in a Tunisian patient: tabetic arthropathy].

Tabetic arthropathy (TA) is a type of neuropathic arthropathy that has become rare. The purpose of this report is to describe a case of tabetic arthropathy involving the knee. A 53-year-old man was hospitalized for painless right knee arthropathy. Clinical examination demonstrated hydarthrosis of the right knee, peripheral neuropathic syndrome of the lower limbs, and paralysis of the IXth and Xth cranial pairs. Plain radiography showed the presence of lytic lesions in the internal femoral condyle and tibial plateau. Syphilitic serology tests were positive in the blood and cerebrospinal fluid.