Synovial haemangioma of the knee

Abstract

Introduction: Synovial hemangioma is a benign vascular malformation of the synovium, usually found as a monoarticular lesion, most frequently in the knee either as a localized or diffused form. The symptoms include prolonged low-intensity pain, which does not interfere with the activities of daily living, occasional swelling, and sometimes hemarthrosis of the joint unrelated to the injury. The gold standard for diagnosis nowadays is magnetic resonance imaging, while treatment options include removal of the lesion with either open or arthroscopic surgery, embolization, or radiotherapy. We report a case of a patient who underwent arthroscopic removal of intra-articular localized synovial hemangioma of the knee. Case report: A 36-year-old man presented with one year of low-intensity pain in the anterior part of the knee and with occasional swelling, which was not the result of an injury. At physical examination, full range of motion and no knee swelling was present. The mild pain on palpation in the anterior part of the lateral joint space was noted. Magnetic resonance imaging of the knee showed the anterolateral part nodular tumor in contact with the Hoffa fat pad. The lesion was arthroscopically excised, and the diagnosis of the synovial hemangioma was confirmed on histopathologic examination of the arthroscopic biopsy. During the three-and-half-year follow-up, the patient was symptom-free, while the control magnetic resonance imaging of the knee performed 24 months after surgery demonstrated no recurrence of the synovial hemangioma. Conclusion: Treatment of synovial hemangioma of the knee depends on its extension and location, so it must be individualized, and today, surgical removal is considered the method of choice. Although there are no definitive guidelines, the prevailing opinion is that all localized forms of synovial hemangioma of the knee should be removed by arthroscopic surgery, which we did in our patient.