Abstract

Tuberculosis of a prosthetic knee joint is rare. Early diagnosis would improve the outcome, but this is usually not achieved. We report the case of a 73-year-old woman who presented with a painful and swollen knee joint, 14 years after total knee arthroplasty. Radiographs and haematological investigations were inconclusive. Synovial tissue and pus obtained by needle biopsy did not reveal any microorganism on smear examination nor in culture. A diagnosis of tuberculosis was made on the basis of a positive polymerase chain reaction. The patient made a complete recovery following brace immobilization for 3 weeks and administration of anti-tubercular drugs for 18 months. There was no recurrence after a follow-up period of 3 years. Awareness of delayed tuberculosis as an important differential diagnosis in infected prosthetic joints helps to avoid delay in management. The authors found 23 other cases of periprosthetic tuberculosis after total knee or hip replacement. Their case is probably the only periprosthetic knee tuberculosis in the literature which healed with medication only. This shows that conservative treatment is possible when there is no loosening of the implant. However, surgical treatment is necessary in most cases and must be individualized.