Papillary endothelial hyperplasia within synovial haemangioma of the flexor tendon sheath of the wrist

A 60-year-old housewife presented with a painful and slowly enlarging swelling in the left wrist for 3 months. Plain X-ray showed mild soft tissue swelling and ultrasonography tenosynovitis of the flexor tendons. Exploration revealed a vascular growth involving the synovium of the flexor tendon sheath of the left little finger. Synovectomy and excision of the entire growth led to the diagnosis of synovial haemangioma with areas of recent haemorrhage and florid papillary endothelial hyperplasia. The recent haemorrhage corresponded to the sudden increase in size, while the papillary endothelial hyperplasia accounted for the persistence and gradual enlargement of the lesion. The patient made an uneventful recovery and remained well more than 2 ½ years after the operation.