Severe heterotopic ossification post total knee arthroplasty in a patient with rheumatoid arthritis: a case report

Stiffness following total knee arthroplasty (TKA) can be a devastating complication to the patient by limiting his function. Various causes have been reported in the literature, including heterotopic ossification (HO). HO is one of the rarely reported complication of TKA characterized by deposition of bone cells in non-skeletal tissue. This is a case of 32-year-old female known to have rheumatoid arthritis with history of TKA 4-years-ago complaining of right knee pain and restricted range of motion. She was later found to have HO and was treated with a revision TKA. In conclusion, the incidence and outcome of HO following total knee replacement in patients with RA remains underexplored topic in the literature.