Fibrolipohamartoma of the Upper Extremity: Treatment Results in Six Patients over Nine Years

Background: Fibrolipohamartoma (FLH) is a rare, benign congenital malformation of peripheral nerves, mainly the median nerve, less frequently of the ulnar or other nerves. Early symptom is an initially painless, slowly growing and circumscript swelling. Affections at the wrist level or the foot are occasionally accompanied by macrodactyly. Although FLH is a congenital disorder, because of absent or discreet symptoms, the diagnosis is often made in early adulthood only due to a compression neuropathy. Magnetic resonance image findings are pathognomonic, biopsies are not necessary. In the medical literature, FLH has been described for the past forty years only by means of case reports or small case series. Meanwhile, surgical decompression is considered as therapeutic gold standard, in case of an accompanying macrodactyly in combination with corrective procedures for length, breadth and axis. Aim of the study: To study long term results after surgical compression of FLH und thus an assessment of this therapeutical concept generally accepted as gold standard in this rare entity. Patients and Methods: Between 1994 and 2004 we treated 9 patients (8 women, 1 man) with 11 tumors, average age was 38 years (3-62). 2 of the 9 patients had macrodactyly. In 7 patients, the median nerve was affected, in one patient bilaterally, in 5 patients the ulnar nerve, and in one patient both ipsilateral median and ulnar nerves. Of those 9 patients, we were able to follow up 6 clinically and electroneurographically. In addition, the DASH-score was collected. Average follow-up after initial decompression was 9 years (2-23). We performed surgical decompression in 5 patients, one patient was treated conservatively. Results: Patients with affections of the median nerve showed tendentially better results after surgical decompression compared to those with FLH of the ulnar nerve, irrespective of the affected anatomical level. Surgical decompression led to a relief of the symptoms in all patients; an improvement of motor function, hypaesthesia and cold sensitivity, however, could not be demonstrated. Conclusion: FLH must be considered in the differential diagnosis of macrodactyly. We recommend surgical decompression, as it leads to relief of the symptoms. It does, however, not have a beneficial effect on already present motor impairments, sensory deficits and cold sensitivity. We strictly advise against tumor resection.