Peripheral nerve compression secondary to adjacent lipomas.

BACKGROUND: Nonneural sheath origin tumors include some rare benign and malignant lesions, and the compression of peripheral nerves by benign fatty tumors is infrequently reported in the medical literature. This study aims to review the authors' experience in treating patients with peripheral nerve compressions secondary to adjacent lipomas.
METHODS: This study is a retrospective analysis of data about the patients who presented peripheral nerve compressive symptoms secondary to lipomas in the upper and lower limbs, treated during the period of 1999 to 2006. Included in the cases were those wherein the tumor was in contact with the nerve and the symptoms matched a respective nerve sensitive and/or motor innervation pattern.
RESULTS: The upper extremity was the site of 5 (62.5%) of 8 lipomas, followed by the lower limb (2 lesions, 25%), and 1 tumor involved the brachial plexus (12.5%). In 5 cases, the clinical picture was similar to some entrapment neuropathy. Ultrasound imaging was useful to define the mass as a nonneural sheath origin tumor; MRI allowed a better analysis of the relationship of the tumor with other vascular, bony, or ligamentous structures. The lesions were ressected in all the patients, and there was good outcome in 7 cases (87.5%). Otherwise, we could identify signs of external compression on the direct inspection of the involved nerves in only 2 cases.
CONCLUSIONS: The surgical treatment offers good outcomes in pain relief and neurological recovery, but one should not expect a real compression effect of the lipoma on the nerve during surgery.