Secondary frozen shoulder following septic arthritis – An unusual complication of magnetic resonance arthrogram

INTRODUCTION: Magnetic resonance (MR) arthrogram is a commonly used investigation tool to detect various pathologies in the shoulder. The complications following this procedure is minor and rare. Septic arthritis is one of the rare complications which can develop after MR arthrogram. We report a case of secondary frozen shoulder after MR arthrogram induced septic arthritis. PRESENTATION OF CASE: A young, fit and well female patient underwent MR arthrogram to detect any labral tears. Two days following the procedure, she developed signs and symptoms suggestive of septic arthritis of the shoulder. The patient underwent repeated arthroscopic debridement and washout. The organisms isolated was Staphylococcus epidermidis. She was treated with six weeks of intravenous antibiotics. The patient developed stiffness of the shoulder due to secondary frozen shoulder which was treated with arthroscopic capsular release with good functional outcomes at three months. DISCUSSION: MR arthrogram is a rare cause of septic arthritis of the shoulder. The common method introducing the organisms is from the skin flora or contaminated arthrogram trays. The treatment is repeated arthroscopic washouts and six weeks of appropriate intravenous antibiotics. Residual pain, stiffness and chondrolysis are common sequelae of septic arthritis. CONCLUSION: Septic arthritis is a recognised and rare complication of MR arthrogram. Early and prompt diagnosis with arthroscopic washout and debridement combined with intravenous antibiotics helps to eradicate the infection. Secondary frozen shoulder is a late complication of sepsis in the joint.