Fibrolipomatous hamartoma of the median nerve with isolated thumb macrodactyly

F ibrolipomatous hamartomas (FLH) are rare tumors primarily involving the wrist, although they have been described in the foot and leg. It was first described by Mason in 1953 as a rare benign tumor of the hand. FLH is often associated with the median nerve and can become painful or cause weakness when compressed by the palmar fascia. Two-thirds of patients with FLH also have macrodactyly. MRI may assist in the diagnosis of these soft-tissue tumors. In a study by De Maeseneer et al., these tumors were hypointense on T1and T2-weighted images and followed the typical branching of the nerves.The typical clinical course of patients with FLH includes paresthesias in the hand, macrodactyly, and a palpable mass. While median nerve involvement is involved in 80% of patients, ulnar and peroneal nerve involvement has been described. We present the case of a 14-year-old boy with chronic hand swelling, median nerve weakness and paresthesia, and isolated macrodactyly. The patient’s parents were informed that details of his case would be presented for print and electronic publication and provided informed written consent.