A Huge Plantar Intramuscular Hemangioma in the Plantar Area Treated Surgically: A Case Report and Literature Review.

Intramuscular hemangioma (IH) is rare, accounting for only 0.8% of all hemangioma cases. In particular, IH of the foot has only been reported a few times. In such cases, the symptoms typically include tenderness and swelling, often in relation to physical activity, but tingling or impaired function may also be present. Here, we report a patient who presented with a significant IH in the plantar area treated surgically. A 25-year-old female visited our hospital with pain in the plantar aspect of the right foot. She had noticed a mass about 10 years prior. She had previously experienced pain only when pressing the mass, but the pain subsequently became more regular pain and was exacerbated by exercise. In fact, the pain became so intense that she could not sleep well. Upon physical examination, mild swelling and tenderness of the plantar area were noted in the second to the fourth metatarsal. Sensation and motor reflexes were normal and the results of Tinel's test were negative. Plain radiographs of the right foot revealed phleboliths scattered throughout the first to third intermetatarsal spaces. Magnetic resonance imaging revealed a space-occupying multilobulated mass (5.6 × 2.8 × 2.5 cm) located in the flexor digitorum brevis (FDB) muscle, which penetrated the plantar fascia and spread to the subcutaneous layer. In T2-weighted images, the lesion displayed a hyperintense signal compared to the surrounding skeletal muscle. Based on radiological findings, we suspected IH. The mass surrounded by the FDB muscle was exposed and completely removed via wide excision. IH consisting of cavernous-like vascular structures was diagnosed on pathology. At 1-year follow-up, the patient was almost asymptomatic and had recovered almost full range of motion in the plantar area. Histological analysis and surgery are recommended to remove intramuscular hemangiomas in the plantar area, but if the patient is not suitable for surgery, sclerotherapy or combination treatment should also be considered.