A previously unreported cause of pain after total knee arthroplasty.

Total knee arthroplasty achieves consistently excellent results in most patients. The most common causes of failure are loosening and infection. This article reviews the records of five patients in whom intraarticular fibrous tissue hypertrophy was the cause of pain after total knee arthroplasty. All of the patients had increasing pain and decreasing knee motion. Evaluation for loosening, malalignment, intraarticular debris, and infection gave negative results. Examination revealed a blocked range of motion and a palpable, tender, intraarticular mass. Injection of anesthetic relieved the symptoms. Surgical excision of the hypertrophic fibrous tissue relieved symptoms and increased knee range of motion. This cause of pain in the total knee arthroplasty patient is rare.