Clinical Implications of the Epidural Fat Thickness in the Management of Lumbar Spinal Stenosis

Could Spinal Epidural Lipomatosis Be the Hallmark of Metabolic Syndrome on the Spine? A Literature Review with Emphasis on Etiology

Spinal epidural lipomatosis is defined by an excessive amount of epidural fat in the spinal canal, usually in the lumbosacral tract: a well-known cause of lumbar pain and spinal stenosis with a possible wide range of neurological symptoms. Recent research data reveal that, nowadays, obesity has become the main cause of spinal epidural lipomatosis. Moreover, this condition was recently recognized as a previously unknown manifestation of metabolic syndrome. Radiological studies (CT and MRI) are the only tools that are able to diagnose the disease non-invasively. Indeed, radiologists play a key role in disease recognition, with subsequent possible implications on patients' systemic health assessments. Despite its clinical importance, the condition is still underreported and neglected. The current literature review summarizes all the main etiologies of spinal epidural lipomatosis, particularly regarding its linkage with metabolic syndrome. An overview of disease characteristics from diagnosis to treatment strategies is also provided.

Imaging of muscle and adipose tissue in the spine: A narrative review

Interpretation of the morphology and characteristics of soft tissues, such as paravertebral muscles and fat, has always been a "relative blind spot" in the spine. The imaging features of the non-bony structures of the spine have been studied and reinterpreted, and changes in the non-bony structure are associated with spinal disease. Soft tissue parameters such as, the "paraspinal muscle cross-sectional area," "subcutaneous fat thickness," and the "paraspinal muscle fat infiltration rate" on computed tomography, magnetic resonance imaging and other imaging techniques are reproducible in the diagnosis, treatment and prognosis of spinal disorders and have the potential for clinical application. In addition, focus on the association between sarcopenia and spinal epidural lipomatosis with spinal disorders is increasing. Currently, there is no summary of studies on fat and muscle in the spinal region. Given this, within the context of recent research trends, this article provides a synthesis of research on adipose and muscle tissue in the spine, discusses advances in the study of the imaging manifestations of these structures in spinal disorders, and expands the perspectives.

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.