Intraneural lipoma of the median nerve: a case report

Introduction

Intraneural lipomas and lipofibromas (also called lipofibromatous hamartomas) are rare, benign tumours occurring in peripheral nerves in the forearm and wrist. They usually present as asymptomatic masses, but if they are large enough, they may cause symptoms of compression neuropathy. Intraneural lipomas and lipofibromas differ with regard to anatomy and clinical behaviour: the former tumour has a well-defined capsule and most commonly occurs within the median nerve in the forearm and wrist. It is diagnosed in the fourth and fifth decades of life and seen more frequently in women. The latter (lipofibroma) has no capsule, is infiltrative in nature, is composed of fatty and fibrous tissue and also most commonly seen in the median nerve. It occurs in a younger age group with no sexual predominance. Due to these differences, these lesions are managed differently [1] [2].

Intraneural lipomas are very rare tumours, reported only as single cases. They were most commonly found in the median nerve in the forearm and wrist and single cases have been reported within the ulnar and radial nerves (radial: two cases in posterior interosseous nerve and one in superficial branch of the nerve) [1] [2] [3] [4] [5] [6] [7] [8]. All except two reported cases included location of the tumour in the forearm; only two cases were reported on digital nerves [2] [9]. In this article we report a case of intraneural lipoma found in the median nerve in the wrist, proximal to the carpal tunnel. The tumour was accidentally diagnosed in a patient suffering from long-lasting bilateral carpal tunnel syndrome (CTS).

Publication History

Article published online:
24 October 2023

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