Giant Solitary Synovial Osteochondromatosis of The Knee in a Young Female

Introduction: Giant Synovial osteochondromatosis of Hoffa’s body is very uncommon. Although described as a benign disease, it can be destructive and can cause severe osteoarthritis and pain. Case report: We report an 18 year old female patient presented with a calcified mass inside the Hoffa’s body. Clinically, patient presented with eight-month history of progressively worsening left knee pain with associated swelling. The bony mass in the Hoffa’s body was evident on the X-ray. MRI showed synovial affectation. During the arthroscopy, all pathological synovial was removed and the bony mass was extirpated through a mini-arthrotomy. Diagnosis of a giant synovial osteochondromatosis was confirmed by histology and malignancy was ruled out. Five years after surgery the patient has been asymptomatic and motion range is complete. Conclusion: This case of primary synovial chondromatosis is interesting because it was presented in an age, gender and unusual location. At 5 years of postoperative follow-up the patient has had no recurrence and has showed excellent performance of the knee joint.