ABSTRACT
Cavernous hemangiomas are uncommon lesions and, as such, may enter the differential diagnosis of other lesions encountered more frequently in clinical practice, including pigmented villonodular synovitis and traumatic hemarthrosis. We report an illustrative case in a young patient in the Rheumatology Department of University Hospital of Fez in Morocco. The aim of our work is: To present to the reader this rare pathology. Of which the diagnosis can be late or misdiagnosed because of the non specificity of symptoms and the underestimation of this pathological entity. To assess the contribution of magnetic resonance imaging [MRI] in the diagnosis and surgical planning of synovial hemangioma of the knee. A 19 year old single Morrocan woman who presented a non specific chronic knee tumefaction secondary to cavernous angioma confirmed radiologically and histologically, with a good evolution after surgery. Cavernous hemangioma of the knee is a frequently misdiagnosed lesion. MRI is the exploration of choice for this vascular tumor of the synovial membrane, although a pathology study is needed to confirm the diagnosis. Early surgical treatment with excision of the tumor within wide margins of uninvolved normal synovial tissue as partial or total synovectomy is the therapy of choice