What are the causes of myelopathy in the lumbar spine?

From the Guidelines

Myelopathy in the lumbar spine is a misnomer, as true myelopathy cannot occur in the lumbar spine, and what is often referred to as "lumbar myelopathy" is actually cauda equina syndrome or lumbar radiculopathy, which requires immediate medical attention if symptoms of cauda equina syndrome are present 1.

Definition and Diagnosis

Myelopathy refers specifically to damage or compression of the spinal cord, but the spinal cord typically ends at the L1-L2 vertebral level in adults, forming the conus medullaris before continuing as the cauda equina (a bundle of nerve roots) 1.

• The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel 1.
• Imaging plays a crucial role in the evaluation of myelopathy with MRI the preferred modality 1.

Treatment and Management

Cauda equina syndrome is a serious neurological condition involving compression of the nerve roots below the spinal cord, presenting with symptoms like lower back pain, leg weakness, saddle anesthesia, and bowel/bladder dysfunction 1.

• It requires immediate medical attention, usually surgical decompression within 48 hours to prevent permanent neurological damage 1.
• Treatment depends on the underlying cause, which may include herniated discs, tumors, infections, or trauma 1.
• Conservative management with pain medications, physical therapy, and activity modification may be appropriate for milder cases of lumbar radiculopathy, but any signs of cauda equina syndrome warrant emergency evaluation 1.

Importance of Distinction

The distinction between myelopathy and radiculopathy is important because they involve different anatomical structures and may require different treatment approaches 1.

• A multidisciplinary approach is necessary for the optimal diagnosis and management of patients with spinal metastases or other conditions that may cause myelopathy or radiculopathy 1.
• Guidelines such as the Dutch national guideline on metastases and hematological malignancies localized within the spine provide evidence- and consensus-based recommendations for the standard of care 1.

From the Research

Myelopathy in Lumbar Spine

• Myelopathy is a clinical diagnosis based on symptoms and physical examination findings, with compressive myelopathy from degenerative disease of the vertebral column being the most common cause in older adults 2.
• The diagnosis of myelopathy involves laboratory and imaging tests, particularly magnetic resonance imaging, to suggest a cause and rule out other conditions 2, 3, 4.
• Myelopathies can be caused by various factors, including infectious, immune-mediated, nutritional, vascular, and neoplastic etiologies 2, 3, 4.

Clinical Approach to Myelopathy Diagnosis

• A clinical approach to myelopathy diagnosis involves an integrative strategy to evaluate patients with suspected myelopathy, providing advice on diagnostic approach and outlining the framework for etiologic diagnosis 3.
• Advances in diagnostic neuroimaging techniques and improved understanding of immune pathogenic mechanisms have expanded knowledge of inflammatory and noninflammatory myelopathies 3.
• Myelopathies exhibit a wide variety of motor, sensory, gait, and sensory disturbances, producing major neurologic disability, and knowledge of clinical variety and strategies for precise diagnosis can help improve outcomes 3.

Evaluation and Management of Acute Myelopathy

• Acute myelopathies are characterized by a rapidly progressive course, reaching nadir within hours to a few weeks, and may result in severe disability 4.
• Awareness of clinical and magnetic resonance imaging characteristics of different myelopathies is fundamental for a correct diagnosis, and neuroimaging helps distinguish compressive etiologies from intrinsic etiologies 4.
• Differentiation between various myelopathies is essential to establish timely and appropriate treatment and avoid harm from unnecessary procedures 4.

Treatment of Lumbar Radiculopathy

• Epidural steroid injections (ESIs) can be used to treat lumbar radiculopathy, with evidence suggesting they probably reduce short-term pain and disability, and possibly decrease long-term disability 5.
• The use of ESIs in lumbar spinal stenosis possibly reduces short-term and long-term disability, but there is insufficient evidence to determine whether they reduce long-term pain 5.
• Further studies are needed to determine the effectiveness of ESIs in reducing pain and disability in cervical and lumbar radiculopathies and spinal stenosis 6, 5.