Intraneural fibrolipoma are rare benign tumours composed of fibrofatty tissue infiltrating the epineurial and perineurial spaces of peripheral nerves. These masses can cause compression neuropathies, presenting with pain and sensory disturbance. Involvement of digital nerves is extremely rare with a paucity of cases documented within the literature.
We report on a 64-year-old man presenting with a five-year history of a slowly enlarging painful subcutaneous mass in the pulp of the right ring finger following crush injury. MRI identified a lobulated fatty mass extending from the proximal interphalangeal joint to pulp, closely associated with the ulnar digital neurovascular bundle.
The patient was initially planned for marginal excision under local anaesthesia. However intra-operatively, the lobulated fibrofatty mass was found to be inseparable, arising within and expanding the digital nerve fascicles necessitating sacrifice. Subsequent histopathological review shows this to be an intraneural fibrolipoma, infiltrating the epineural and perineurial spaces.
This case highlights an extremely rare presentation of intraneural fibrolipoma involving a digital nerve. Surgical management of these lesions is a significant reconstructive challenge, underscoring its importance as a differential diagnosis during pre-operative workup and planning.