Cauda equina syndrome secondary to idiopathic spinal epidural lipomatosis

A challenging diagnosis of spinal epidural lipomatosis: A case report and review of the literature

INTRODUCTION

Spinal Epidural Lipomatosis (SEL) is a rare disorder of pathological overgrowth of the spinal epidural fat in the extradural space. The pathogenesis of SEL usually involves exogenous steroid use or endogenous steroids overproduction. However, idiopathic cases have been reported. Magnetic resonance imaging (MRI) is the gold standard for diagnosis. Both conservative and surgical approaches are employed in management of these patients.

CASE PRESENTATION

A 17-year-old male presented to our hospital complaining of progressive lower limb weakness, loss of sensation with urinary incontinence which ended up with paraplegia. He underwent extensive investigations and received multiple inaccurate diagnoses. MRI of the thoracic spine showed spinal epidural lipomatosis with dorsal kyphosis. Hemi-laminectomy for spinal cord decompression and trans-pedicular fixation for correction of kyphosis were performed showing excellent outcomes.

CLINICAL DISCUSSION

Diagnosing SEL can be challenging due to its symptom overlap with other neurological conditions. Thus, higher levels of clinical suspicions and utilization of numerous diagnostic modalities including MRI are required. Treatment is largely determined by the clinical presentation and the severity of symptoms. Given the severity of neurological symptoms in our case, surgical intervention was performed resulting in fully regained functionality of previously paralyzed muscles.

CONCLUSION

This case highlights the rare presentation and the diagnostic challenges of spinal epidural lipomatosis SEL in a young patient who was misdiagnosed for 9 consecutive months before receiving the correct diagnosis, emphasizing the importance of considering SEL in the differential diagnosis for progressive neurological deficits and the importance of MRI, especially in atypical cases.

Extravertebral low back pain: a scoping review

BACKGROUND

Low back pain (LBP) is one of the most common reasons for consultation in general practice. Currently, LBP is categorised into specific and non-specific causes. However, extravertebral causes, such as abdominal aortic aneurysm or pancreatitis, are not being considered.

METHODS

A systematic literature search was performed across MEDLINE, Embase, and the Cochrane library, complemented by a handsearch. Studies conducted between 1 January 2001 and 31 December 2020, where LBP was the main symptom, were included.

RESULTS

The literature search identified 6040 studies, from which duplicates were removed, leaving 4105 studies for title and abstract screening. Subsequently, 265 publications were selected for inclusion, with an additional 197 publications identified through the handsearch. The majority of the studies were case reports and case series, predominantly originating from specialised care settings. A clear distinction between vertebral or rare causes of LBP was not always possible. A range of diseases were identified as potential extravertebral causes of LBP, encompassing gynaecological, urological, vascular, systemic, and gastrointestinal diseases. Notably, guidelines exhibited inconsistencies in addressing extravertebral causes.

DISCUSSION

Prior to this review, there has been no systematic investigation into extravertebral causes of LBP. Although these causes are rare, the absence of robust and reliable epidemiological data hinders a comprehensive understanding, as well as the lack of standardised protocols, which contributes to a lack of accurate description of indicative symptoms. While there are certain disease-specific characteristics, such as non-mechanical or cyclical LBP, and atypical accompanying symptoms like fever, abdominal pain, or leg swelling, that may suggest extravertebral causes, it is important to recognise that these features are not universally present in every patient.

CONCLUSION

The differential diagnosis of extravertebral LBP is extensive with relatively low prevalence rates dependent on the clinical setting. Clinicians should maintain a high index of suspicion for extravertebral aetiologies, especially in patients presenting with atypical accompanying symptoms.

Transthyretin amyloid deposition in ligamentum flavum (LF) is significantly correlated with LF and epidural fat hypertrophy in patients with lumbar spinal stenosis

Lumbar spinal stenosis (LSS) is a degenerative disease characterized by intermittent claudication and numbness in the lower extremities. These symptoms are caused by the compression of nerve tissue in the lumbar spinal canal. Ligamentum flavum (LF) hypertrophy and spinal epidural lipomatosis in the spinal canal are known to contribute to stenosis of the spinal canal: however, detailed mechanisms underlying LSS are still not fully understood. Here, we show that surgically harvested LFs from LSS patients exhibited significantly increased thickness when transthyretin (TTR), the protein responsible for amyloidosis, was deposited in LFs, compared to those without TTR deposition. Multiple regression analysis, which considered age and BMI, revealed a significant association between LF hypertrophy and TTR deposition in LFs. Moreover, TTR deposition in LF was also significantly correlated with epidural fat (EF) thickness based on multiple regression analyses. Mesenchymal cell differentiation into adipocytes was significantly stimulated by TTR in vitro. These results suggest that TTR deposition in LFs is significantly associated with increased LF hypertrophy and EF thickness, and that TTR promotes adipogenesis of mesenchymal cells. Therapeutic agents to prevent TTR deposition in tissues are currently available or under development, and targeting TTR could be a potential therapeutic approach to inhibit LSS development and progression.

The Most Impactful Articles on Cauda Equina Syndrome

Cauda equina syndrome (CES) is an uncommon condition that can lead to permanent neurological deficits if not diagnosed and addressed promptly. Varying prognoses, including retropulsed fracture fragments, disc herniations, and epidural abscesses, can result in CES. Our objective was to identify the top 50 most impactful articles on CES and analyze the characteristics of these publications. In August of 2021, we used the Web of Science Core Collection bibliographic database to query the phrase "cauda equina syndrome." Articles between 1900 and 2021 were included in the search, and these articles were ranked based on the number of citations. The following variables were recorded: title, first author, journal, year of publication, number of citations, country of origin, the institution of publication, and topic of the paper. A total of 2096 articles matched the search criteria. The top 50 most impactful articles ranged from 43 to 439 in their number of citations. All articles on the list were published in English, with the year of publication ranging from 1938 to 2014. The United States accounted for the greatest number of articles published at 27. The medical journal Spine accounted for the greatest number of publications at nine. And the 2000s was the decade with the most cited articles. It is generally acknowledged that the clinical signals for CES are diverse with no predictive value on patient outcomes. Similar uncertainty exists in the etiology of the condition, though CES induced by spinal anesthesia is a factor of particular interest. Additionally, it is generally recognized that delayed diagnosis of the condition often results in permanent neurological deficits. Identification of the most impactful articles on CES is critical in drawing attention to this significant condition.

Rates of Future Lumbar Fusion in Patients with Cauda Equina Syndrome Treated With Decompression

INTRODUCTION

The long-term risk of conversion to lumbar fusion is ill-defined for patients with cauda equina syndrome (CES) treated with decompression. This study aimed to identify the rates of fusion in patients with CES and compare those rates with a matched lumbar spinal stenosis (LSS) group.

METHODS

Patients with CES who underwent decompression were identified in a national database and matched to control patients with LSS. The rates of conversion to fusion were identified and compared. Multivariate logistic regression analysis identified independently associated risk factors. A subanalysis was conducted after stratifying by timing between CES diagnosis and decompression.

RESULTS

The rate of lumbar fusion in the CES cohort was 3.6% after 1 year, 6.7% after 3 years, and 7.8% after 5 years, significantly higher than the LSS control group at all time points (1 year: 1.6%, P = 0.001; 3 years: 3.0%, P < 0.001; 5 years: 3.8%, P < 0.001). CES was independently associated with increased risk of conversion to fusion (odds ratio: 2.13; 95% confidence interval: 1.56 to 2.97; P < 0.001). Surgical timing was not associated with risk of conversion to fusion.

CONCLUSIONS

After 5 years, 7.8% of patients with CES underwent fusion, a markedly higher rate compared with patients with LSS. Counseling patients with CES on this increased risk of future surgery is important for patient education and satisfaction.

Percutaneous full-endoscopic uniportal decompression for the treatment of symptomatic idiopathic lumbar spinal epidural lipomatosis: Technical note

Background

Lumbar spinal epidural lipomatosis (SEL) is a rare condition characterized by an excessive accumulation of adipose tissue within the spinal canal, compressing the dura sac and/or nerve roots. When conservative treatments fail and clinical symptoms progress quickly and seriously, surgical decompression should be considered. With the rapid development of endoscopic armamentaria and techniques, the pathological scope that can be treated by percutaneous endoscopic spine surgery is ever expanding.

Objective

In this paper, the authors describe a patient with lumbar spinal epidural lipomatosis who was treated with a percutaneous full-endoscopic uniportal decompression surgery successfully. This article aims to validate the feasibility of percutaneous full-endoscopic uniportal decompression for the treatment of symptomatic idiopathic spinal epidural lipomatosis via interlaminar approach.

Methods

We describe a case of a 69-year-old man with a 10-year history of low back pain, intermittent claudication, and bilateral leg neuropathic pain. He was diagnosed with lumbar epidural lipomatosis, which did not respond to conservative therapy. After a comprehensive evaluation, he underwent percutaneous endoscopic spine surgery to remove hyperplastic adipose tissue and decompress nerve roots and dura sac.

Results

The patient was treated with a percutaneous full-endoscopic uniportal decompression surgery successfully. After the procedure, his leg pain decreased and his walking capacity improved. There were no surgery-related complications, such as cerebrospinal fluid leakage, incision infection, etc.

Conclusions

The case with SEL was successfully treated with a percutaneous full-endoscopic uniportal surgery, which has the advantages of excellent presentation of anatomical structures, expanded field of vision, less surgical-related trauma, and bleeding. The key point of the procedure is to release and cut off the bands which divide the epidural space into small rooms filled with excess adipose tissue.

Lumbar laminotomy and replantation for the treatment of lumbar spinal epidural lipomatosis: A case report

RATIONALE

Lumbar spinal epidural lipomatosis (SEL) is a rare condition characterized by excessive overgrowth of extradural fat within the lumbar spinal canal. Surgical decompression is commonly performed to treat symptomatic SELs. Fenestration or laminectomy with epidural fat debulking was a routine surgical procedure according to the literature, that may be causing postoperative lumbar instability. In the present study, we presented a brief report of lumbar SEL and introduced another surgical approach.

PATIENT CONCERNS

A 55-year-old man complained of severe low back pain and right leg radicular pain for a year, accompanied by neurogenic intermittent claudication. He received a variety of conservative treatments, including non-steroidal anti-inflammatory drugs, acupuncture, and physical therapy. However, his pain did not diminish. Finally, a posterior epidural mass in the dorsal spine extending from the L3 to L5 level, which caused dural sac compression was found on lumbar magnetic resonance imaging. This mass was homogeneously hyperintense in both T1W1 and T2W1 images, suggestive of epidural fat accumulation.

DIAGNOSES

Lumbar SEL.

INTERVENTIONS

The patient underwent lumbar laminectomy, epidural fat debulking, and spinous process-vertebral plate in situ replantations.

OUTCOMES

The patient presented with complete recovery of radiculopathy and low back pain after surgery. Postoperative magnetic resonance imaging showed that the increased adipose tissue disappeared, and the dural sac compression was relieved. A computed tomography scan revealed the lumbar lamina in situ. He was able to walk normally and remained relatively asymptomatic for 12 months after the operation at the last follow-up visit.

LESSONS

Lumbar laminotomy and replantation provide an ideal option to treat lumbar SEL because it can achieve sufficient and effective decompression, simultaneously reconstruct the anatomy of the spinal canal, and reduce the risk of iatrogenic lumbar instability.

An investigation and validation of CT scan in detection of spinal epidural adipose tissue

To investigate the accuracy of computed tomography (CT) in evaluating spinal epidural adipose tissue compared to magnetic resonance imaging (MRI).CT scan images and matched magnetic resonance images of total 368 patients between July 2014 and July 2016 were evaluated. Hounsfield units (HU) of epidural fat (EF), dural sac (DuS), ligamentum flavum, bone of facet joints, and paraspinal muscles were measured for comparison. Anteroposterior diameter of the EF, anteroposterior diameter of the DuS, transverse diameter of the DuS, cross-sectional area of the EF, and cross-sectional area of the DuS were measured at each disc level from L1-2 to L5-S1.Fat tissue showed exclusive negative HU significantly different from all other periphery tissues. Pearson correlation coefficient analyses showed significant positive correlations between CT and MRI measurements; Bland-Altman plots also depicted satisfied agreement. Overgrowth of spinal EF was more commonly found at L2-3 and L3-4 levels in present study, and body weight, age, and gender were significantly associated with amounts of EF both on CT and MRI.The CT scan is a satisfied alternative of MRI for the evaluation of spinal epidural adipose tissue.

Spinal Epidural Lipomatosis: A Review of Pathogenesis, Characteristics, Clinical Presentation, and Management

STUDY DESIGN

Narrative review of available literature.

OBJECTIVE

To summarize current trends in pathogenesis and management of spinal epidural lipomatosis (SEL) and suggest areas where more research would be of benefit.

METHODS

The available literature relevant to SEL was reviewed. PubMed, Medline, OVID, EMBASE, Cochrane, and Google Scholar were used to review the literature. Institutional review board approval is not applicable for this study.

RESULTS

This article clearly summarizes current trends in the pathogenesis and management of SEL.

CONCLUSIONS

Possible etiologies of SEL include exogenous steroid use, endogenous steroid hormonal disease, obesity, surgery induced, and idiopathic disease. Comorbidities such as acquired immunodeficiency syndrome and Scheuermann's disease have also been implicated in the pathogenesis of SEL. Steroid-induced SEL seems to have a proclivity for the thoracic region of the spine and has a higher incidence of paraplegia when compared with other forms. Several treatment modalities exist for SEL and are dictated by the underlying cause of the disorder. These include weight reduction, cessation of steroid medications, treatment of underlying endocrine abnormalities, and surgical decompression. Conservative treatments generally aim to decrease the thickness of adipose tissue in the epidural space, but the majority of patients tend to undergo surgical decompression to relieve neurologic symptoms. Surgical decompression provides a statistically significant reduction in symptoms, but postoperative mortality is high, influenced primarily by the patient's preoperative comorbidities. Physicians should consider the underlying cause of SEL in a given patient before pursuing specific treatment modalities, but alarm symptoms, such as the development of acute cauda equina syndrome, should likely be treated with urgent surgical decompression.

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.

Spinal epidural lipomatosis is a previously unrecognized manifestation of metabolic syndrome

BACKGROUND CONTEXT

Spinal epidural lipomatosis (SEL) is a condition in which excess lumbar epidural fat (EF) deposition often leads to compression of the cauda equina or nerve root. Although SEL is often observed in obese adults, no systematic research investigating the potential association between SEL and metabolic syndrome has been conducted.

PURPOSE

To elucidate potential association between SEL and metabolic syndrome.

STUDY DESIGN

An observational study used data of a medical checkup.

PATIENT SAMPLE

We retrospectively reviewed data from consecutive subjects undergoing medical checkups. A total of 324 subjects (174 men and 150 women) were enrolled in this study.

OUTCOME MEASURES

The correlation of EF accumulation with demographic data and metabolic-related factors was evaluated.

METHODS

The degree of EF accumulation was evaluated based on the axial views of lumbar magnetic resonance imaging. Visceral and subcutaneous fat areas were measured at the navel level using abdominal computed tomography. Metabolic syndrome was diagnosed according to the criteria of the Japanese Society of Internal Medicine. The correlation of SEL with metabolic syndrome and metabolic-related conditions was statistically evaluated.

RESULTS

The degree of EF accumulation demonstrated a significant correlation to body mass index, abdominal circumference, and visceral fat area. However, age, body fat percentage, and subcutaneous fat area showed no correlation with the degree of EF accumulation. Logistic regression analysis revealed that metabolic syndrome (odds ratio [OR]=3.8, 95% confidence interval [CI]=1.5-9.6) was significantly associated with SEL. Among the diagnostic criteria for metabolic syndrome, visceral fat area ≥100 cm² (OR=4.8, 95% CI=1.5-15.3) and hypertension (OR=3.5, 95% CI=1.1-11.8) were observed to be independently associated with SEL.

CONCLUSION

This is the first study to demonstrate that metabolic syndrome is associated with SEL in a relatively large, unbiased population. Our data suggest that metabolic-related conditions are potentially related to EF deposition and that SEL could be a previously unrecognized manifestation of metabolic syndrome.

Rapid Development of Spinal Epidural Lipomatosis after Treatment of Metastatic Castration-Resistant Prostate Cancer with Second-Generation Androgen Receptor Antagonists

BACKGROUND

Previous studies have described the association of spinal epidural lipomatosis with several conditions including chronic steroid therapy, Cushing's syndrome, obesity, Paget disease, and hypothyroidism. We present a report of rapid development of spinal epidural lipomatosis after treatment with second-generation anti-androgen therapy, a new strategy for treatment of metastatic castration-resistant prostate cancer that has been increasingly employed in the past few years. A comprehensive discussion of the underlying molecular networks involving androgen receptor blockage and adipocyte differentiation, as well as the clinical implications of such a phenomenon, are provided.

CASE DESCRIPTION

We describe the clinical and radiological evolution of a 58-year-old male patient with metastatic prostate cancer, who developed new onset of rapidly progressing lumbosacral epidural lipomatosis with significant compression of the nerve roots of the cauda equina a few months after initiation of treatment with second-generation androgen receptor antagonists.

CONCLUSIONS

The underlying pathophysiology of adipose tissue growth following the administration of anti-androgen therapy is discussed, with emphasis on both the canonical Wnt/β-catenin pathway as well as in the Wnt-independent pathway involving direct activation of downstream transcription factors from the T-cell factor family by the androgen receptor. As second-generation androgen receptor antagonists have been increasingly used for treatment of castration-resistant stage metastatic prostate cancer, new onset of symptomatic epidural lipomatosis should be considered as a possible differential diagnosis, especially because the urinary symptoms of cauda equina compression may be improperly attributed to the primary prostate neoplasm.

Obesity and spinal epidural lipomatosis in cauda equina syndrome

BACKGROUND CONTEXT

Although lumbar disc herniations are common, only a small portion of these herniations lead to cauda equina syndrome (CES), which is an uncommon but debilitating disorder. Why some patients with herniation develop CES, when most do not, remains unknown. Preexisting subclinical epidural lipomatosis may limit canal space such that an otherwise benign herniation causes CES.

PURPOSE

This study determines whether patients with an acute disc herniation and CES have a greater body mass index (BMI) and greater quantity of epidural fat compared with control subjects with non-CES symptomatic lumbar herniated discs.

STUDY DESIGN/SETTING

A retrospective case-control series at a university-based level-1 trauma center was carried out.

PATIENT SAMPLE

There were 33 CES and 66 control subjects identified from a prospectively maintained database of patients who underwent surgical management for a lumbar disc herniation between 2007 and 2012. Each CES case had two non-CES control patients matched by gender and age within 5 years except 5 CES cases that matched only one non-CES control.

OUTCOME MEASURES

The outcome measures included weight, height, age, gender, and BMI. Radiographic outcome measures included the proportion of lumbar spinal canal occupied by fat and herniated disc on preoperative magnetic resonance imaging.

METHODS

Patient charts and preoperative radiographs were retrospectively reviewed. For each patient, a blinded reviewer determined the proportion of lumbar spinal canal occupied by fat, and the maximal proportion of the canal occupied by herniated material at the involved level. Patient demographics and radiographic measures were compared between CES and control groups using chi-square or Student t tests. A second blinded reviewer re-assessed a series of radiographs, and the intraobserver variability was determined by Spearman correlation. Logistic regression was used to model the preoperative factors associated with having an acute disc herniation and CES.

RESULTS

The CES cases had higher BMI (31.8 kg/m², 95% confidence interval [CI] 29.5-34.0 vs. 28.1 kg/m², 95% CI 26.7-29.5 in controls; p=.007), focally narrower canals (14.6 mm, 95% CI 13.8-15.3 mm vs. 16.4 mm, 95% CI 15.4-17.3 mm in controls; p=.003), and a greater percentage of spinal canal occupied by epidural fat (31.3%, 95% CI 26.1%-36.6% vs. 21.9%, 95% CI 18.7%-25.1% in controls; p=.003) and herniated disc material (54.5%, 95% CI 46.9%-62.0% vs. 34.4%, 95% CI 30.3%-38.5% in controls; p<.0001). Logistic regression confirmed canal width at the involved level, BMI, amount of canal occupied disc, and proportion of canal occupied by fat as independent predictors of having an acute disc herniation and CES.

CONCLUSIONS

Obesity is a risk factor for CES from disc herniation. The CES cases also had a greater amount of herniated material, focally narrower canal, and larger epidural fat deposits. The latter may be the mechanism linking obesity with CES.

Epidural lipomatosis with cauda equina syndrome in chronic alcoholic patient: A case report

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Case of epidural lipomatosis with cauda equina syndrome in chronic alcoholic patient is provided.

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Posterior decompression was applied and neurologic deficit was significantly recovered.

•

MRI is the best imaging tool of choice. Short T1 inversion recovery (STIR) sequence may be useful for confirmation of diagnosis as lipid is hypointense in this sequence.

Introduction

Epidural lipomatosis of the lumbar spine is a rare condition, which is described as the accumulation of fat in the extradural territory.

Presentation of case

We report the case of a 60-year-old, non-obese, and chronic alcoholic man who was transferred to our spine department with cauda equina syndrome (CES) for 4 months. On magnetic resonance imaging (MRI), spinal epidural lipomatosis (SEL) was confirmed in the multilevel lumbar lesion. A decompression surgery was performed and the patient recovered significantly.

Discussion

The patient was not obese, had no abnormal liver laboratory test results, and no history of steroid injection or administration. The clinical signs at onset suggested bilateral lower cauda equina dysfunction, indicating a more diffuse involvement, consistent with lumbosacral epidural lipomatosis.

Conclusion

This case report is the first description of SEL in a non-obese, chronic alcoholic patient who was neither receiving steroids nor had any kind of endocrinopathy.

Potential Involvement of Obesity-Associated Chronic Inflammation in the Pathogenesis of Idiopathic Spinal Epidural Lipomatosis

STUDY DESIGN

Multicenter case-control study.

OBJECTIVE

To characterize the pathogenesis of idiopathic spinal epidural lipomatosis (SEL).

SUMMARY OF BACKGROUND DATA

SEL is often associated with the history of steroid use or endocrine disorders; however, the pathogenesis of idiopathic SEL remains poorly understood.

METHODS

Sixteen patients who underwent lumbar decompression surgery due to severe idiopathic SEL were included in the study (L group, 15 men and 1 woman; mean age, 71.5 yrs). Fifteen patients without SEL, who underwent decompression surgery for lumbar canal stenosis, were selected as controls (C group, 14 men and 1 woman; mean age, 70.3 yrs). The following parameters were analyzed in these two groups: body mass index (BMI), medical history, histology, the size of adipocytes in the epidural fat (EF) tissues, and the expression level of the transcripts for adiponectin, leptin, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and IL-8.

RESULTS

The mean BMI of the L group was significantly higher than that of the C group (29.1 vs. 25.2 kg/m, P = 0.006), and there was a significant correlation between BMI and the width of EF in both groups. The average adipocyte size in the EF was significantly larger in the L group than in the C group (2846.8 vs. 1699.0 μm, P = 0.017). Furthermore, the expression levels of the transcripts for TNF-α and IL-1β in the L group were significantly higher than those in the C group [2.59-fold increase (P = 0.023) and 2.60-fold increase (P = 0.015), respectively].

CONCLUSION

Our data suggest that the pathogenesis of idiopathic SEL is associated with obesity. In addition, the increased expression of two major inflammatory cytokines in the EF in the L group may indicate that SEL is causally related to chronic inflammation.

LEVEL OF EVIDENCE

3.

Patient-reported outcome of surgical treatment for lumbar spinal epidural lipomatosis

BACKGROUND CONTEXT

Spinal epidural lipomatosis (SEL) is a rare condition characterized by an excessive accumulation of fat tissue in the spinal canal that can have a compressive effect, leading to clinical symptoms. This condition has a distinct pathology from spinal stenosis associated with degeneration of the intervertebral discs, ligaments, and facet joints. Several different conservative and surgical treatment strategies have been proposed for SEL, but its treatment remains controversial. There is a lack of evidence documenting the success of surgical decompression in SEL, and no previous studies have reported the postoperative outcome from the patient's perspective.

PURPOSE

The aim of the present study was to evaluate patient-rated outcome after surgical decompression in SEL.

STUDY DESIGN

A retrospective analysis of prospectively collected data was carried out.

PATIENT SAMPLE

A total of 22 patients (19 males; age: 68.2±9.9 years) who had undergone spine surgery for SEL were identified from our local Spine Surgery Outcomes Database, which includes a total of 10,028 spine surgeries recorded between 2005 and 2012. Inclusion criteria were epidural lipomatosis confirmed by preoperative magnetic resonance imaging (MRI) scans and subsequent decompression surgery without spinal fusion.

OUTCOME MEASURES

The Core Outcome Measures Index (COMI) was used to assess patient-rated outcome. The COMI includes the domains pain (separate 0-10 scales for back and leg pain), back-specific function, symptom-specific well-being, general quality of life (QOL), work disability, and social disability.

METHODS

The questionnaires were completed preoperatively and at 3, 12, and 24 months postoperatively. Surgical data were retrieved from the patient charts and from our local Spine Surgery Outcomes Database, which we operate in connection with the International Spine Tango Registry. Differences between pre- and postoperative scores were analyzed using paired t tests and repeated measures analysis of variance.

RESULTS

At 3-months follow-up, the COMI score and scores for leg pain and back pain had improved significantly compared with their preoperative values (p<.005). The mean decrease in COMI score after 3 months was 2.6±2.4 (range: -1.3 to 6.5) points: from 7.5±1.7 (range: 3.5-10) to 4.9±2.5 (range: 0.5-9.6). A total of 11 patients (50%) had an improvement of the COMI of more than the minimal clinically important change (MCIC) score of 2.2 points. The mean decrease in leg pain after 3 months was 2.4±3.5 (-5 to 10) points. Overall, 17 patients (77.3%) reported a reduced leg pain, 12 (54.6%) of whom by at least the MCIC score of 2 points. The significant reductions from baseline in COMI and leg and back pain scores were retained up to 2 years postoperatively (p<.02). The general QOL item of the COMI improved significantly after surgery (p<.0001). Over 80% of the cohort rated their preoperative QOL as bad (n=13) or very bad (n=5), whereas 3 months after surgery, only 7 patients rated their QOL as bad, and one as very bad (36%).

CONCLUSIONS

The present study is the first to demonstrate that surgical decompression is associated with a statistically significant improvement in patient-rated outcome scores in patients with symptomatic SEL, with a clinically relevant change occurring in approximately half of them. Surgical decompression hence represents a reasonable treatment option for SEL, although the reason behind the less good response in some patients needs further investigation.

[Spinal epidural lipomatosis as a rare side effect in steroid-dependent Jo-1 antibody syndrome]

Spinal epidural lipomatosis (SEL) of the thoracic and lumbar spine is a rare entity, which leads to compression of the spinal canal. The exact pathogenesis is still unknown. It most commonly occurs in patients with long-term exogenous or endogenous glucocorticoid excess or morbid obesity but there are also idiopathic forms. The symptoms depend on the severity of the SEL and can manifest as clinically asymptomatic, non-specific back pain, radiculopathy up to spinal cord compression. The diagnosis is usually achieved by magnetic resonance imaging (MRI) of the affected spinal segments. The treatment varies between discontinuation of glucocorticoids, weight reduction up to multisegmental decompressive laminectomy. The following case report presents the findings of SEL in a patient with steroid-dependent Jo-1 antibody syndrome and provides a current literature review on this rare 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.

[Spinal epidural lipomatosis]

Spinal epidural lipomatosis (SEL) is a rare condition affecting the thoracic and lumbar spine, characterized by a hypertrophy and hyperplasia of the rich vascularized fat tissue inside the spinal canal. The etiology of SEL is unknown. A high number of cases are associated with obesity, corticosteroid intake and a dysbalance in adrenocorticotropic hormone (ACTH)-cortisone metabolism. It can be an incidental radiographic finding or present with symptoms, such as low back pain, weakness of the lower limbs, dysesthesia, radiculopathy, claudication or even cauda equina syndrome. The interdisciplinary treatment consists of weight reduction, weaning from corticosteroids and in persisting cases or neurologic alterations in surgical decompression of the spinal canal. The following article presents a current review and a case report of this rare entity.

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 epidural lipomatosis in children with hematologic malignancies

Abnormal fat deposition in the epidural space or spinal epidural lipomatosis (SEL) due to corticosteroid treatment or obesity may cause obstruction to cerebrospinal fluid flow. Little is known about SEL in patients with hematologic malignancies who require frequent lumbar punctures and corticosteroid treatment that places them at risk. Records and radiologic images of patients with SEL and leukemia or non-Hodgkin lymphoma (NHL) treated at a single institution from 1999-2009 were reviewed. Risk factors were compared with 405 control patients with leukemia. Fourteen patients with leukemia or NHL were diagnosed with SEL. The majority of patients underwent diagnostic imaging after unsuccessful lumbar punctures within 1 month of their primary diagnosis. Prior to SEL diagnosis, all patients received systemic and/or intrathecal corticosteroids. SEL diagnosis led to modification of intrathecal administration in eight patients, including Ommaya reservoir placement in four patients. All patients completed protocol-specified chemotherapy without neurologic symptoms or surgical intervention. Risk factors for developing SEL include older age and high body mass index. Investigation for SEL in leukemia or lymphoma patients with difficult lumbar punctures is warranted. Placement of an Ommaya reservoir may facilitate safe CNS-directed therapy in severely affected patients.

Spinal cord stimulation in a patient with spinal epidural lipomatosis

BACKGROUND AND OBJECTIVE

Spinal cord stimulation is the most commonly used implantable neurostimulation modality for management of pain syndromes. For treatment of lower extremity pain, the spinal cord stimulator lead is typically placed in the thoracic epidural space, at the T10-T12 levels. Typically, satisfactory stimulation can be obtained relatively easily. Anatomical variability in the epidural space, such as epidural scarring, has been reported to prevent successful implantation of spinal cord stimulators. Spinal epidural lipomatosis describes an abnormal overgrowth of adipose tissue in the extradural space. Cases have documented spinal epidural lipomatosis complicating intrathecal baclofen pump implantation or causing repeated failure of epidural analgesia. However, so far, there is no published literature describing how spinal epidural lipomatosis affects spinal cord stimulation.

CASE REPORT

We report a case of spinal cord stimulation in a patient with spinal epidural lipomatosis. Very high impedance was encountered during the trial spinal cord stimulator lead placement. Satisfactory stimulation was only obtained after repeated repositioning of the spinal cord stimulator trial lead. Post-procedure thoracic spine magnetic resonance imaging revealed marked thoracic epidural lipomatosis. At the level where satisfactory stimulation was obtained, the thickness of the epidural fat was within normal limits. The patient eventually underwent placement of a laminotomy lead with good coverage and pain relief.

CONCLUSION

Spinal epidural lipomatosis significantly increases the impedance in the epidural space, making effective neurostimulation very difficult to obtain. Physicians should consider the possibility of spinal epidural lipomatosis when very high impedances are encountered during lead placement.

Dorsal epidural spinal lipomatosis

The authors report a case of a thoracic epidural spinal lipomatosis causing severe neurological deficits along the review of pertinent literature. The patient is a 56-year-old woman who presented with acute onset of severe paraparesis; she was investigated with cervical and thoracic MRI and then surgically managed because of an intraspinal mass compressing the cord. The operation consisted in the excision of the mass confirmed to be a fibrolipoma by pathological analysis. The patient attained complete neurological recovery and at 18 months follow-up she reported a generalised well-being. Thoracic lipomas are rare lesions that presenting mostly with back pain; however, in rare instances they may cause progressive and/or abrupt neurological dysfunction. Appropriate imaging can help in the diagnosis and management of such cases.

Sudden paraplegia following epidural lipomatosis and thoracal compression fracture after long-term steroid therapy: a case report

Sudden paraplegia secondary to the posterior spinal epidural compression and vertebral compression fracture as a complication in corticosteroid treatment is extremely rare. The authors presented a case 49-year-old man with chronic relapsing attack of Still's disease. After the identification of pathology, the surgical evacuation of lipid tissue and pedicle-based instrumentation showed therapeutic success. To the authors' knowledge, this is the first case showing both vertebral fracture and paraplegia that required urgent surgery in the follow-up Still's disease.

IMPACT OF BODY HABITUS ON PERIOPERATIVE MORBIDITY ASSOCIATED WITH FUSION OF THE THORACOLUMBAR AND LUMBAR SPINE

OBJECTIVE

Spinal fusion is performed in patients ranging from young and healthy to aged and frail. Although recent population trends in the United States are toward obesity, no large-scale study has evaluated how body habitus affects mortality, complications, and resource utilization for lumbar spine fusion. Such information is important for patient selection and to confirm the safety of such procedures in this population.

METHODS

Data for 244 170 patients who underwent thoracolumbar or lumbar spine fusion for degenerative disease between 1988 and 2004 were collected from the Nationwide Inpatient Sample database, and subjects were grouped by surgical approach and body habitus. Multivariate logistic regression evaluated group effects on selected postoperative complications, length of stay, resource utilization, and discharge disposition.

RESULTS

This study confirms that body habitus affects perioperative morbidity sustained by patients undergoing thoracolumbar or lumbar spine fusion. Demographic heterogeneity exists for race, geography, and number of diseased levels among body habitus groups, prompting application of multivariate logistic regression for outcomes. For all approaches, higher body mass index associated with increased transfusion requirements and likelihood of discharge to assisted living. Furthermore, morbidly obese patients undergoing posterior fusion sustained more wound complications and postoperative infections.

CONCLUSION

This nationwide study describes inpatient complications encountered during fusion surgery in patients who are obese. For a given surgical approach, patients with higher body mass index sustain increased transfusion requirements and utilize more resources during thoracolumbar and lumbar spine fusion. Nevertheless, the findings of equivalent mortality, length of stay, and other complication rates suggest that patients who are obese remain safe surgical candidates.

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.

Spinal epidural lipomatosis--a brief review

Spinal epidural lipomatosis (SEL) is a rare disorder characterized by overgrowth of fat in the extradural space, causing compression of the neural elements. It is frequently associated with the administration of exogenous steroids or elevation of endogenous steroids. We present two patients, both with epidural lipamotosis of idiopathic origin. One was 53-year-old man with progressive mid-thoracic and lower limb pain with associated weakness and neurogenic claudication due to thoracic epidural lipomatosis. The second was a 68-year-old male with lumbar epidural lipomatosis. Co-morbidities for the first patient included diabetes and obesity; however, there was no history of steroid administration. An MRI scan revealed thoracic cord compression, with significant stenosis at T4-T9. The second patient complained of progression of longstanding lumbar pain and claudicant symptoms. There was no history of steroid intake. An MRI revealed stenosis at L4-S1 and diffuse anterior lipomatosis. A literature review revealed 49 cases of idiopathic SEL and 62 of secondary SEL. We aimed to delineate the differences between these two relatively distinct entities including their anatomical distribution, clinical presentation and prognostic implications.

Does abdominal obesity cause increase in the amount of epidural fat?

It is known that epidural fat does not alter in obese people. This study aims to find out a possible relationship with epidural fat and abdominal obesity. In this cross-sectional study, 63 patients who were referred to our clinic for lumbar magnetic resonance imaging (MRI) examination were evaluated. Patients with the history of steroid treatment, thyroid disease or Cushing disease were excluded. Waist circumferences (WC), body weight and height were measured and subsequently body-mass index (BMI) was calculated (kg/m(2)). On midsagittal T1-weighted images, anterior epidural fat (AEF), posterior epidural fat (PEF) and posterior subcutaneous fat (SCF) thicknesses were measured at the S1 level. The results were compared with age, gender, body weight, height, WC and BMI. There were 31 men and 32 women, age ranged 19-77 years (mean 49). The mean BMI was 29.25 kg/m(2) (20.7-52.7); the mean WC was 97.4 +/- 13.2 cm (72-122) in women and 97.6 +/- 9.8 cm (72-118) in men. Cutoff value of WC was considered as 88 cm for women and 95 cm for men. BMI > 27.5 was considered to be obese. No statistical difference with respect to epidural fat thickness between genders was determined in AEF and PEF (P = 0.237, P = 0.616). SCF was significantly thicker in women (P = 0.021). A very poor and negative correlation was found between age and PEF (r = 0.373, P = 0.003), and a very poor and positive correlation between weight and PEF was found (r = 396, P = 0.001). The thickness of the epidural fat was not differ between obese and nonobese people (p = 0.571 for AEF and p = 0.307 for PEF). The thickness of the epidural fat was not different in people whose WC was greater than normal values in both gender (p > 0.05). Epidural fat is not affected by age, gender, BMI and WC which means that epidural fatty layer. A clear correlation has not been found between epidural fat amount and obesity or abnormal fat distribution yet.

Epidural Angiopomatosis of the Thoracic Spine: Case report and literature review

Spinal epidural angiolipomatosis (SEA) is a rare benign neoplasm of adipose tissue with a prominent vascular component. Classified as either idiopathic or secondary to chronic steroid therapy it accounts for 0.14% of all spinal axis tumours. The clinical and radiological features and treatment of a case in a 24-year-old male are described and discussed together with a review of the literature and previous reports.

Epidural lipomatosis

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.

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.

Thoracic spinal epidural lipomatosis associated with adolescent scoliosis

Although a variety of neural axis abnormalities in association with idiopathic scoliosis have been reported, there are no documented cases of spinal epidural lipomatosis (SEL) in a child with scoliosis. An otherwise healthy, neurologically intact 14-year-old girl presented with spinal deformity. Radiographs confirmed a left thoracic, right lumbar Lenke class 5CN scoliosis. Preoperative magnetic resonance imaging (MRI) demonstrated extensive SEL in the thoracic spine. She underwent posterior spinal fusion with segmental instrumentation using bony anchors that did not violate the spinal canal. Intraoperative spinal cord monitoring and postoperative clinical course were uneventful. SEL should be added to the list of potential abnormalities to be looked for in children with spinal deformities undergoing preoperative MRI of the neural axis.

Myeloneuropathic presentation of spinal epidural lipomatosis

Spinal epidural lipomatosis (SEL) is accumulation of unencapsulated fat tissue within the epidural space of the spinal canal. The most common cause of SEL is corticosteroid therapy, whereas most of the non-corticosteroid-dependent cases are idiopathic. If unrecognized, it may result in diagnostic confusion with other neuropathic or myelopathic conditions. We report 2 cases of SEL. The first case is of a 30-year-old man who received corticosteroid therapy for an acute and probably immune-mediated demyelinating process. Subsequently, the addition of compressive effects of SEL resulted in diagnostic confusion and initial workup at other centers for spinal cord malignancy and vascular malformation. The patient's symptoms improved after decompression surgery. The second case is of a 63-year-old woman with a history of type 1 diabetes mellitus that presented with increasing numbness in the lower extremities. She was initially diagnosed with diabetic neuropathy; however, the presence of myelopathic signs led to further investigation and diagnosis of SEL. Decompression surgery resulted in improvement of symptoms.

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.

Epidural spinal lipomatosis with acute onset of paraplegia in an HIV-positive patient treated with corticosteroids and protease inhibitor: case report

STUDY DESIGN

Case report.

OBJECTIVE

To report a case of HIV-related lipodystrophy with a rapid onset of symptoms from epidural lipomatosis in the wake of protease inhibitor and steroid treatment.

SUMMARY OF BACKGROUND DATA

Symptomatic spinal epidural lipomatosis is considered to be a rare condition usually presenting with slowly progressive cord or nerve root compression. Only 2 cases of spinal lipomatosis in HIV-related lipodystrophy have been reported.

METHODS

We describe the case of a 41-year-old male with HIV who received protease inhibitor medication and had neurologic deficits rapidly develop.

RESULTS

The patient had complete paraplegia develop within 12 hours from admission following a 1-day history of unsteady gait and a 3-day history of leg numbness. After diagnosis of epidural lipomatosis on magnetic resonance imaging, the patient underwent decompressive thoraco-laminectomy. He recovered well and was able to walk by postoperative day 4.

CONCLUSION

It is important to maintain an awareness for the possible association between HIV lipodystrophy and symptomatic epidural lipomatosis.

Is epidural lipomatosis associated with abnormality of body fat distribution? A case report

CASE REPORT

To report a case of epidural lipomatosis in a patient with abnormal adipose tissue distribution, glucose intolerance and mixed hyperlipidemia. A 63-year-old male patient presented with low back pain radiating to the left calf on standing and walking (walking distance <100 m). He weighed 97.5 kg, was 1.73 m tall (BMI 32.6 kg/m2) and had a waist circumference of 113 cm. He had a glucose intolerance after a 75-g glucose oral load test. CT-Myelography revealed voluminous epidural lipomatosis around L4-L5 and L5-S1. Low calorie diet and reduction in alcohol intake achieved a weight loss of 17.5 kg in 7 months (80 kg, BMI 25.8 kg/m2, waist circumference 94 cm) and dramatic improvement in low back pain, walking distance (>500 m) and reduction of lipomatosis on CT-scan. Our case suggests a relationship between central obesity phenotype and epidural lipomatosis. Specific insulin resistance treatment might be proposed for these patients if this hypothesis is confirmed in further studies.

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.

Is Epidural Fat Associated With Body Habitus?

OBJECTIVE

To evaluate, in the spine, the relationship between the amount of epidural fat to body weight, height, body mass index (BMI), presence of obesity, depth of posterior subcutaneous fat, as well as gender and age.

METHODS

At 1.5 T, 101 random patients were analyzed. In the lumbar spine, we calculated the depth of the anterior and posterior epidural fat, as well as posterior subcutaneous fat, separately at the L3-4, L4-5, and L5-S1 levels. Obtained via questionnaire was patient's age, gender, body weight, height, with a calculated BMI (body weight/height, kg/m). Statistical analysis was performed to assess the correlation between epidural and subcutaneous fat with age and gender, weight, height, BMI, and presence of obesity (BMI > 27.5 kg/m).

RESULTS

There were 66 men and 45 women, age ranged 14-83 years old (mean 43). The weight range was 47.6-135.4 (mean 79.5 kg); height range was 124.5-208.3 (mean 169.7 cm); BMI range was 16.9-42.8 (mean 27.8). Female gender correlated only with subcutaneous fat depth (sum, r=-0.31, P=0.002). Younger patients had more anterior epidural fat (sum, r=-0.22, P=0.024) but not posterior epidural fat (sum, r=0.01, P=0.954) or subcutaneous fat (sum, r=0.09, P=0.0357). Weight correlated with posterior epidural fat (sum, r=0.21, P=0.037) and subcutaneous fat (sum, r=0.51, P <0.0001). Height showed correlation negatively with posterior subcutaneous fat thickness (sum, r=-0.25, P=0.014), but had no significant correlation with epidural fat. BMI showed a correlation with posterior subcutaneous fat (r=0.71, P <0.0001 for sum). Somewhat unexpectedly, BMI had no correlation with either posterior (r=0.12, P=0.221 for sum) or anterior epidural fat (r=0.11, P=0.271 for sum), and most importantly the presence of obesity was associated only with subcutaneous fat (P <0.0001), but not with any specific or summated epidural fat measurement (P=0.0801-0.7692).

CONCLUSION

Weight but not body habitus is associated with specific, usually posterior, patterns of epidural fat deposition. Overall obesity is unrelated to epidural fat.

Epidural Steroid Injections in the Treatment of Symptomatic Lumbar Spinal Stenosis Associated with Epidural Lipomatosis

Epidural lipomatosis has been implicated as a cause or contributor of symptomatic lumbar spinal stenosis. Although epidural steroid injections have been very successful for symptomatic treatment of spinal stenosis; their role in treatment of symptomatic stenosis secondary to epidural lipomatosis is unclear. A review literature (MEDLINE, PubMed) found no reports justifying the use of steroids. We present two patients with lumbar epidural lipomatosis causing or contributing to symptomatic spinal stenosis. Both patients presented with unilateral lower limb radicular symptoms unrelieved with conservative measures such as medications and physical therapy. They were treated with a single transforaminal epidural steroid injection at the symptomatic level. Both had 80-85% pain relief. These reports suggest a beneficial role of epidural steroid injections for patients with symptomatic lumbar spinal stenosis caused by or contributing to epidural lipomatosis.

Spinal epidural lipomatosis: a review of its causes and recommendations for treatment

Spinal epidural lipomatosis is most commonly observed in patients receiving long-term exogenous steroid therapy, but can also be seen in patients with endogenous steroid overproduction, obesity, or idiopathic disease. With this condition, there is hypertrophy of the epidural adipose tissue, causing a narrowing of the spinal canal and compression of neural structures. A majority of patients will present with progressive myelopathy, but radicular symptoms are also common. Conservative treatment—weaning from steroids or weight loss—can reverse the hypertrophy of the adipose tissue and relieve the neural compression. If conservative management fails, surgery with decompressive laminectomy is also very successful at improving the patient's neurological symptoms.