Idiopathic spinal epidural lipomatosis

OBJECTIVE: Spinal epidural lipomatosis (SEDL) is a rare disorder often associated with the administration of exogenous steroids or the elevation of endogenous steroids. Spinal epidural lipomatosis develops in some patients in the absence of elevated steroid levels. The limited information known about idiopathic SEDL comes predominantly from isolated case reports. We proposed to study our experience with idiopathic SEDL and to review the literature. METHODS: We identified eight symptomatic patients with idiopathic SEDL treated at our institution, which is the largest series reported. All patients were male and obese by body mass index (>27.5 kg/m²). The mean age of the patients was 35.4 years. Idiopathic SEDL was equally distributed between the thoracic and lumbar spine. Six patients underwent laminectomy and fat debulking with good postoperative results; two patients were treated with a weight loss diet, which resulted in the relief of symptoms after losing >15 kg each. RESULTS AND CONCLUSION: A review of our patients in conjunction with other reported cases reveals the following: 1) idiopathic SEDL occurs almost exclusively in the obese population; 2) idiopathic SEDL seems to occur with equal frequency between the thoracic and lumber spine; 3) a strong male predominance exists; 4) thoracic SEDL presents at an earlier age compared with lumbar SEDL; 5) surgical decompression remains the treatment of choice for the immediate relief of symptoms. Our experience suggests that idiopathic epidural lipomatosis may be a pathological entity that has been underdiagnosed.