Idiopathic spinal extradural lipomatosis in a non-obese otherwise healthy man

A Novel Percutaneous Biportal Endoscopic Technique for Symptomatic Spinal Epidural Lipomatosis: Technical Note and Case Presentations

OBJECTIVE

To describe a minimally invasive decompression technique for symptomatic spinal epidural lipomatosis using percutaneous biportal endoscopic surgery.

METHODS

In this report, we describe the indirect decompressive effect that was gained by partial laminotomy and ligamentum flavectomy under biportal endoscopic view. Direct neural decompression was then performed by removal of proliferated fat. We described the technical process and compared pre- and postoperative radiating leg pain, life quality, and a radiologic grading system of neural compression.

RESULTS

This technique was performed successfully in 3 patients with idiopathic spinal epidural lipomatosis. Radiating pain was reduced, and functional disability and radiologic compression were improved. Postoperative instability and surgical complications related to the procedure were not observed.

CONCLUSIONS

Percutaneous spinal endoscopy is a minimally invasive muscle-preserving technique for spinal lipomatosis that achieves neural decompression directly by lipoma removal and indirectly by partial bone and ligament removal.

Clinical and imaging characteristics in patients undergoing surgery for lumbar epidural lipomatosis

Background

Lumbar epidural lipomatosis (LEL) is characterized by abnormal accumulation of unencapsulated adipose tissue in the spinal epidural space. Such accumulation compresses the dural sac and nerve roots, and results in various neurological findings. However, the pathophysiology of LEL remains unclear. This study examined the associations between imaging and clinical findings in detail, and investigated the mechanisms underlying symptom onset by measuring intraoperative epidural pressures in LEL.

Methods

Sixteen patients (all men; mean age, 68.8 years) were enrolled between 2011 and 2015. Mean body mass index was 26.5 kg/m². Four cases were steroid-induced, and the remaining 12 cases were idiopathic. All patients presented with neurological deficits in the lower extremities. Cauda equina syndrome (CES) alone was seen in 8 patients, radiculopathy alone in 4, and both radiculopathy and CES (mixed CES) in 4. All patients subsequently underwent laminectomy with epidural lipomatosis resection and were followed-up for more than 1 year. We investigated the clinical course and imaging and measured epidural pressures during surgery.

Results

Subjective symptoms improved within 1 week after surgery. Mean Japanese Orthopaedic Association (JOA) score was 15.2 ± 2.8 before surgery, improving to 25.4 ± 2.5 at 1 year after surgery. On magnetic resonance imaging, all lipomatosis lesions included the L4–5 level. On preoperative computed tomography, saucerization of the laminae was not observed in radiculopathy cases, whereas saucerization of the posterior vertebral body was observed in all radiculopathy or mixed CES cases. Intraoperative epidural pressures were significantly higher than preoperative subarachnoid pressures. The results suggest that high epidural pressure resulting from the proliferation of adipose tissue leads to saucerization of the lumbar spine and subsequent symptoms.

Conclusions

Clinical courses were satisfactory after laminectomy. In LEL, epidural pressure increases and symptoms develop through the abnormal proliferation of adipose tissue. Higher epidural pressures induce saucerization of the laminae and/or posterior vertebral body. Furthermore, the direction of proliferative adipose tissue (i.e., site of saucerization) might be related to the types of neurological symptoms.

Spinal cord compression secondary to idiopathic thoracic epidural lipomatosis in an adolescent: A case report and review of literature

INTRODUCTION

Spinal epidural lipomatosis (SEL) is a rare condition that presents with progressive spinal cord or nerve root compression. It is commonly reported in patients receiving long-term exogenous steroid therapy or in patients with endogenous steroid overproduction. The occurrence of this condition as an idiopathic entity is rarely reported.

CASE PRESENTATION

The authors present the clinical course and outcome of a 16-year-old male student, who presented with progressive spastic paraparesis of a one-year duration caused by idiopathic spinal epidural lipomatosis. Magnetic resonance imaging (MRI) study of the thoracic spine revealed marked compression of the spinal cord from a large dorsally located extradural mass extending from the T-4 to T-12 vertebral bodies. The patient underwent posterior thoracic laminoplasty from the T4 to T10 vertebral levels. He experienced gradual neurological, and he was able to walk without assistant by the end of 3-month follow-up period from surgery.

CONCLUSION

Idiopathic SEL is very rare, since no predisposing factors can be identified, and should be included in the differential diagnosis when patients present with spinal neurological compromise. MRI is the imaging modality of choice, and decompressive laminectomy and debulking of the fatty lesion is the main treatment modality in patients with progressive course of the disease..

Idiopathic Spinal Epidural Lipomatosis in the Lumbar Spine

Overgrowth of epidural fat, known as spinal epidural lipomatosis (SEL), can cause symptomatic compression of the spinal cord, conus medullaris, or cauda equina. Suggested predisposing factors such as obesity, steroid use, and diabetes mellitus have been based on a few reported cases, many of which were not surgically confirmed. There is a paucity of epidemiological data in surgically confirmed cases for this disorder. The purpose of this independently reviewed, retrospective, matched cohort analysis was to compare the demographics and incidence of comorbidities of patients who underwent lumbar decompression for SEL vs degenerative stenosis without SEL. Two surgeons' databases were reviewed to identify patients older than 18 years who underwent decompression surgery for magnetic resonance imaging-verified, symptomatic lumbar SEL. A matched control group comprised an equal number of patients with degenerative stenosis (n=14). Demographic data, body mass index, symptom type/duration, comorbidities, complications, treatment history, and associated pathology were collected from medical records. Previously suggested risk factors, such as obesity, endocrinopathy, and epidural steroid injections, were not significantly different between the SEL and control groups. Furthermore, there were no differences in operative times, complications, or blood loss. The only noted difference between the 2 groups was the preoperative duration of symptoms, on average double in patients with SEL. This series represents the largest of its kind reported to date. Because symptom duration was the only difference noted, it is postulated to be the result of lack of awareness of SEL. Future prospective study in a larger group of patients is warranted. [Orthopedics. 2016; 39(3):163-168.].

Unusual Spinal Epidural Lipomatosis and Lumbosacral Instability

Introduction. Epidural lipomatosis is most frequently observed in patients on chronic steroid treatment. Only a few idiopathic epidural lipomatosis cases have been described. Material and Methods. 64-year-old male patient presented with low back pain and left leg pain. Later, the patient experienced neurogenic claudication and radicular pain in the left leg without urinary dysfunction. Plain radiography and magnetic resonance imaging demonstrated an abnormal fat tissue overgrowth in the epidural space with compression of the dural sac, degenerative disc disease at L4-L5 level, and instability at L5-S1. Endocrinopathic diseases and chronic steroid therapy were excluded. If conservative treatment failed, surgical treatment can be indicated. Results. After surgery, there was a gradual improvement in symptoms and signs, and six months later the patient returned to daily activities and was neurologically normal. Conclusion. In the absence of common causes of neurogenic claudication, epidural lipomatosis should be considered. The standard test for the diagnosis of epidural lipomatosis is magnetic resonance (MR). At first, conservative treatment must be considered; weight loss and the suspension of prior corticosteroid therapy are indicated. In the presence of neurological impairment, the operative treatment of wide surgical decompression must be performed soon after diagnosis.

Idiopathic thoracic epidural lipomatosis with chest pain

Spinal epidural lipomatosis (SEL) is an overgrowth of the normally encapsulated adipose tissue in the epidural space around the spinal cord in the thoracic and lumbar spine causing compression of the neural components. Idiopathic SEL in non-obese patients is exceptional. Idiopathic SEL can result in thoracic myelopathy and lumbar radiculopathy. A thoracic radiculopathy due to idiopathic SEL has not been reported yet. We report a case of idiopathic SEL with intractable chest pain and paresthesia. We suggest that idiopathic SEL should be considered as a cause of chest pain.

[Spinal cord compression caused by idiopathic dorsal epidural lipomatosis: Case report and critical review of the literature]

We report the case of a patient with spinal cord compression evolving over 36 months with spastic paraparesis. Anatomic imagery showed epidural lipomatosis. No predisposing factors were found. Surgical treatment was decided. A T1-T10 laminectomy with excision of the surplus epidural fat was performed. Immediate and medium-term postsurgical follow-up was favorable with the disappearance of the pyramidal syndrome. Other cases found in literature and the principal predisposing factors are discussed.

Lumbar nerve root compression due to extradural, intraforaminal lipoma. An underdiagnosed entity?

Intraspinal extradural lipomas, not associated with spinal dysraphism, are rare lesions. True adult lipomas have to be distinguished from angiolipomas and from epidural lipomatosis. The authors report a unique case of a patient with unilateral lumbar nerve root compression caused by extradural, intraforaminal, true adult lipoma. A 62-year-old woman suffered severe left L-5 radiculopathy that progressively worsened during the 12 months prior to presentation. She did not experience improvement with conservative therapy. An MR imaging study of the lumbar spine revealed shifting of the left L-5 nerve root caused by a small extradural intrarecessal (that is, the beginning of the intravertebral foramen)/intraforaminal mass with MR imaging characteristics of fatty tissue. No other relevant intraspinal pathology could be identified. A left L4-5 fenestration was carried out. A small fatty intrarecessal/intraforaminal mass compressing severely the left L-5 root was identified and completely resected. The histological examination revealed a lipoma. The patient recovered completely and is fully mobile and symptom free 1 year after the operation. Intraspinal lipomas should be considered in cases of radiculopathy, especially in the absence of relevant degenerative or tumorous pathology and in the presence of nerve root shifting caused by fatty tissue.

Decompression of idiopathic symptomatic epidural lipomatosis of the lumbar spine

Epidural lipomatosis has been implicated as a cause or contributor of symptomatic lumbar spinal stenosis. Symptomatic spinal epidural lipomatosis (SEL) of the lumbar spine is a rare disease, often associated with steroid overload. Idiopathic lipomatosis is even much less frequent. Signs and symptoms depend upon the level and degree of nerve root compression. Diagnosis is best based on MRI. Weight reduction can be curative, however, after failure of medical treatment or in severe cases surgical decompression should be performed. A 70-year-old man with both lower limb severe paresthesia and radicular symptoms unrelieved with conservative treatments such as medications and physical therapy was treated by surgical decompression. Obesity, endocrinopathic disease, and chronic steroid therapy were excluded. Interlaminar fenestration, lateral recess decompression and fat debulking were applied at all levels through the L2-S1. After surgery there was a gradual improvement in symptoms. We report a rare case of idiopathic SEL which has shown entire evolvement of lumbar spine with specific increase of radiological and clinical severity from L2-3 to L5-S1 in a non-obese patient.

Decompression of idiopathic lumbar epidural lipomatosis: diagnostic magnetic resonance imaging evaluation and review of the literature

Object

Idiopathic symptomatic spinal epidural lipomatosis (SEL) is a rare condition, and few reports have discussed diagnostic imaging criteria. To evaluate factors relating to its clinical symptoms, correlations between clinical features and the presence of spinal epidural fat were investigated, and the literature concerning idiopathic SEL was reviewed.

Methods

Morphological gradings of epidural fat were evaluated in seven patients with idiopathic SEL by using magnetic resonance (MR) imaging. In addition, body mass index (BMI), the number of involved vertebral levels, grade, and preoperative Japanese Orthopaedic Association (JOA) score were analyzed. Surgery resulted in symptomatic relief, with a mean JOA score recovery rate of 67.4%. Grading of epidural fat tended to display a slight negative correlation with preoperative JOA score, whereas a strong significant positive correlation was found between the number of involved vertebral levels and BMI.

Conclusions

The number of involved vertebral levels and obesity are strongly correlated, whereas severity of dural compression is not always significantly associated with neurological complications. These results indicate that epidural fat of the lumbar spine contributes to neurological deficits. In addition, weight-reduction therapy appears to decrease the number of vertebral levels involved. Magnetic resonance imaging–based grading is helpful for the diagnosis and evaluation of idiopathic lumbar SEL. Moreover, symptoms and neurological findings are important for determining the surgical approach.

Spinal epidural lipomatosis: case reports, literature review and meta-analysis

BACKGROUND CONTEXT

Symptomatic spinal epidural lipomatosis (SEL), a rare cause of spinal cord compression, has most often been associated with exogenous steroid use.

PURPOSE

Identify four associations with SEL, correlate the associated groups with level of disease and compare treatment with outcome data in these groups.

STUDY DESIGN/SETTING

Case reports of three patients and analysis of 104 cases from the literature.

PATIENT SAMPLE

Three patients from the senior author's practice.

OUTCOME MEASURES

Not applicable.

METHODS

The authors report three new cases of SEL not associated with steroid use. They review all available English literature and present a table of all 104 reported cases.

RESULTS

The clinical course of three new patients is reported.

CONCLUSIONS

Associated conditions are exogenous steroid use, obesity, endogenous steroid excess, and some remain idiopathic. Although SEL is a rare condition, our review of the literature reveals many more reported cases than previously thought. With increased awareness of this condition and improved imaging techniques, further studies of this disease should be undertaken.

A case of idiopathic spinal epidural lipomatosis presented with radicular pain caused by compression with enlarged veins surrounding nerve roots

OBJECTIVE

To report a case of idiopathic spinal epidural lipomatosis (SEDL) presented with unique radicular pain most likely caused by enlarged veins surrounding nerve roots.

PATIENT

A 26-year-old male presented with radicular pain of the right T6-T7 area. He also showed Becker's nevus in the corresponding area. CT myelography and magnetic resonance imaging revealed epidural lipomatosis posterior to T4-T8 of the spinal cord. Surgical removal of adipose tissue and a hemilaminectomy of T4-T7 were performed and resulted in relief of the radicular pain.

CONCLUSIONS

Lipomatosis was histologically confirmed and surrounded by enlarged veins. These abnormally enlarged veins compressed the nerve roots and were thought to cause radicular pain. Also, Becker's nevus of this case seems to have some relationship with SEDL.

Epidural lipomatosis secondary to indinavir in an HIV-positive patient

A human immunodeficiency virus-positive patient receiving indinavir therapy developed a slowly progressive paraparesis. Magnetic resonance imaging findings were consistent with epidural lipomatosis. On discontinuing indinavir, symptoms gradually remitted. Although indinavir, a protease inhibitor, is known to cause abnormal fat accumulation, to the best of our knowledge this is the first report of epidural lipomatosis.

Cauda equina syndrome secondary to idiopathic spinal epidural lipomatosis

STUDY DESIGN

Three cases of idiopathic epidural lipomatosis are reported.

OBJECTIVES

Description of the relationship between spinal pathologic overgrowth of fat tissue and neurologic symptoms.

SUMMARY OF BACKGROUND DATA

Idiopathic epidural lipomatosis is a very rare condition; it is usually secondary to chronic steroid therapy or endocrinopathic diseases.

METHODS

Three men with a mean age of 58.5 years, who experienced intermittent claudication, bilateral radicular pain in both legs, and urinary dysfunction with hypoesthesia in the perineal region, were evaluated by plain radiography and magnetic resonance imaging, the results of which demonstrated a pathologic overgrowth of fat tissue in the spinal canal with a marked impingement of the dural sac. Obesity, endocrinopathic diseases, and chronic steroid therapy were excluded for all patients. Surgical treatment was performed by wide multilevel laminectomies, fat debulking, and instrumented posterolateral fusion.

RESULTS

After surgery there was a gradual improvement in symptoms and signs so that 2 years later the patients returned to daily activities and were neurologically normal.

CONCLUSIONS

Spinal epidural lipomatosis can be a cause of back pain but rarely radicular impingement. Magnetic resonance imaging is the procedure of choice. The treatment must be performed early by wide surgical decompression.

Ninety-degree rotation of the thoracic spinal thecal sac. Case report

This 44-year-old man presented with a 4-year history of progressive spastic weakness of his legs. He was found to have epidural lipomatosis behind the thoracic spinal cord, and the nerve roots exited from the posterior and anterior midline planes of the dura, indicating a 90 degree rotation of the thoracic cord. Magnetic resonance images clearly demonstrated the segmental thoracic nerve roots exiting from the dorsal midline of the dura, a finding confirmed at surgery. The authors found only one previously published case of rotation of the spinal cord. Directed mechanical stress caused by deformation of the rotated spinal cord, rather than compression from adipose tissue, is proposed as the mechanism of the myelopathy. The extent, location, and thickness of the associated extradural adipose tissue is suggestive of epidural lipomatosis. The lipomatous tissue might have been an epiphenomenon and cord rotation an isolated congenital anomaly. Alternatively, asymmetrical growth of epidural fat may have exerted torque, rotating the thecal sac.

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.