Tri-compartmental tubercular arthritis of knee masquerading as popliteal fossa tumor: a case report

Abstract

A 50-year old woman of moderate socioeconomicstatus presented to the outpatient clinic of the Ortho-paedics Department at NEIGRIHMS, Shillong, India,complaining of gradual onset of swelling at the back ofher right knee and flexion deformity of the same knee for6 months.She had experienced dull aching pain from 1–2monthsaftertheappearanceof theswelling.Thepainwasgradually increasing and the patient had suffered sleepdisturbance due to pain for the last 2 weeks. She gave ahistory of feeling feverish, especially in the evenings, andof loss of appetite for the last month with no history ofweight loss . The patient did not have symptoms pertain-ing to any other joint. There was no history of swelling,paresthesiae or weakness of the right leg, foot or ankle,and no history of chest pain, cough or hemoptysis, orexposure to tuberculosis.Physical examination revealed atender globular swelling which was soft to firm in consis-tency and measured 6 cm ¥ 8 cm in the right poplitealfossa.Wasting of the right thigh and leg was present. Theskin over the swelling was normal with no dischargingsinus around the knee. There were no dilated veins. Thelocal temperature was not raised. Both medial and lateraljoint lines were tender. There was no joint effusion orsynovial thickening. The patella had restricted mobilitybut was non-tender.The range of motion (flexion) of theknee was from 30