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Lumbar Spinal Stenosis


Peter J. Moley

, MD, Hospital for Special Surgery

Reviewed/Revised Oct 2022
Topic Resources

Lumbar spinal stenosis is narrowing of the lumbar spinal canal causing compression of the nerve rootlets and nerve roots in the cauda equina before their exit from the foramina. It causes positional back pain, symptoms of nerve root compression in the foramina, and lower-extremity pain during walking or weight bearing.

Spinal stenosis can be congenital or acquired. It may involve the cervical or lumbar spine. Acquired lumbar spinal stenosis (LSS) is a common cause of sciatica Sciatica Sciatica is pain along the sciatic nerve. It usually results from compression of lumbar nerve roots in the lower back. Common causes include intervertebral disk herniation, osteophytes, and... read more in middle-aged or older patients. The most common causes of LSS are osteoarthritis Osteoarthritis (OA) Osteoarthritis is a chronic arthropathy characterized by disruption and potential loss of joint cartilage along with other joint changes, including bone hypertrophy (osteophyte formation). Symptoms... read more Osteoarthritis (OA) , degenerative disk disorders, spondylosis Cervical Spondylosis and Spondylotic Cervical Myelopathy Cervical spondylosis is osteoarthritis of the cervical spine causing stenosis of the canal and sometimes cervical myelopathy due to encroachment of bony osteoarthritic growths (osteophytes)... read more , and spondylolisthesis Spondylolisthesis Spondylolisthesis is slippage of a lumbar vertebra in relation to the vertebra below it. Anterior slippage (anterolisthesis) is more common than posterior slippage (retrolisthesis). Spondylolisthesis... read more Spondylolisthesis with compression of the cauda equina. Other causes include Paget disease of bone Paget Disease of Bone Paget disease of bone is a chronic disorder of the adult skeleton in which bone turnover is accelerated in localized areas. Normal matrix is replaced with softened and enlarged bone. The disease... read more Paget Disease of Bone and ankylosing spondylitis Ankylosing Spondylitis Ankylosing spondylitis is the prototypical spondyloarthropathy and a systemic disorder characterized by inflammation of the axial skeleton, large peripheral joints, and digits; nocturnal back... read more Ankylosing Spondylitis .

Symptoms and Signs of Lumbar Spinal Stenosis

In patients with lumbar spinal stenosis, pain occurs in the buttocks, thighs, or calves during walking, running, climbing stairs, or even standing. This pain is referred to as neurogenic claudication. The pain is not relieved by standing still but by flexing the back or by sitting (although paresthesias may continue). Walking up hills is less painful than walking down because the back is slightly flexed. Patients may have pain, paresthesias, weakness, and diminished reflexes in the affected nerve root distribution.

Rarely, sudden nerve rootlet compression resulting from LSS or a large disk herniation may cause cauda equina syndrome Symptoms and Signs with distal leg paresis and sensory loss in and around the perineum and anus (saddle anesthesia), as well as bladder, bowel, and pudendal dysfunction; unlike in spinal cord injury, muscle tone and deep tendon reflexes are decreased in the legs.

Diagnosis of Lumbar Spinal Stenosis

  • Clinical evaluation

  • Sometimes MRI, electrodiagnostic studies, or both

Spinal stenosis is suspected based on characteristic symptoms of pain that is increased by exertion (neurogenic claudication) and relieved with sitting and/or with back flexion. Muscle strength is usually maintained, but focal weakness, sensory loss, and diminished deep tendon reflexes may be present.

Calf symptoms may simulate those of intermittent vascular claudication. Vascular claudication can be differentiated by relief with rest (not position change), skin atrophy, and abnormalities in pulses, capillary refill, and vascular tests.

Treatment of Lumbar Spinal Stenosis

  • Activity as tolerated, analgesics, and sometimes drugs that relieve neuropathic pain

  • Physical therapy

  • Possibly epidural corticosteroid injections

  • Surgery for severe cases

Epidural corticosteroid injections sometimes provide transient relief. In symptomatic patients who are poor candidates for surgical intervention, the combination of epidural injections and flexion-based physical therapy can result in some symptomatic improvement.

For advanced spinal stenosis, surgery involves decompression of nerve root entrapment by vertebral canal and foraminal encroachments, which sometimes requires laminectomy at 2 or 3 levels plus foraminotomies and sometimes fusion surgery.

Spinal stability must be preserved. Spinal fusion may be indicated if there is instability or severe, well-localized arthritic changes in 1 or 2 vertebral interspaces; however, some studies highlight the controversial nature of this approach (1, 2 Treatment references Lumbar spinal stenosis is narrowing of the lumbar spinal canal causing compression of the nerve rootlets and nerve roots in the cauda equina before their exit from the foramina. It causes positional... read more Treatment references ).

Treatment references

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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