SPINAL STENOSIS

Jung U. Yoo, M.D.Professor and Chairman

Department of Orthopedics and Rehabiliatation

Oregon Health and Science University

STABILITY

• ORDINARY ACTIVITIES MAY GENERATE OVER 1000LB OF FORCE

MOTION

NEUROPROTECTION

• SPINAL CORD• NERVE ROOTS

PATHOPHYSIOLOGY

• “Three-joint Complex”– a large tripod with the

disc as the front support and two facet joints as the back supports

– Any alteration in one of these joints can lead to damage to the others

STENOSIS

STENOSIS

• Compresses the exiting nerve root

FORAMINAL STENOSIS

CANAL SHAPE

• Round

• Triangular

• Trefoiled (15%)

• Trefoiled & asymmetric

DEGENERATION & STENOSIS

PREVALENCE

• Most common indication for spinal surgery in patients over 60 y.o.

• 400,000 Americans are estimated to have spinal stenosis

STENOSIS

• Narrowing of the spinal canal or neuroforamina

• causing a symptomatic compression of the neural element.

SYMPTOMS

• Neurogenic claudication

• Radicular pain

• Weakness

• Sensory abnormalities

• Back pain

PHYSICAL FINDINGSPhysical Finding Literature

Review

• Limited lumbar extension 66-100%• Muscle weakness 18-52%• Sensory deficit 32-58%

• Katz JN, et al: Diagnosis of lumbar spinal stenosis. Rheum. Dis. Clin. North Am. 20:471-483, 1994

NEUROGENIC CLAUDICATION

• Cardinal symptom of lumbar stenosis

• Progressive pain and/or paresthesia in the back, buttock, thigh and calves brought on by walking or standing, and relieved by sitting or lying down with hip flexion

POSTURE

AMBULATION

DIFFERENTIAL DIAGNOSIS

• Vascular claudication

• Osteoarthritis of hip or knee

• Lumbar disc protrusion

• Intraspinal tumor

• Unrecognized neurologic disease

• Peripheral neuropathy

• Root symptoms• Unilateral• No claudication• Acute or chronic

FORAMINAL STENOSIS

• Claudication• Radicular pain• Weakness is rare• Acute or chronic

LATERAL RECESS STENOSISLATERAL RECESS STENOSIS

CENTRAL STENOSIS

• Varied presentation• Classically with

neurogenic claudication

• Some may only have back pain

• Rarely painless progressive weakness

DIAGNOSTIC TESTS

X-RAY

• Screening exam• Stenosis cannot be

diagnosed

X-RAY

• Instability such as scoliosis or listhesis

CT SCAN

• Difficult to diagnose stenosis

• Replaced by MRI• May be useful for those

who cannot have an MRI

CT SCAN

• Excellent bony detail

MRI

• Non-invasive• Soft tissue

visualization• Gold standard

MRI

• Sagittal images• Visualization of

foramen

• Excellent for intra-canal pathology

• Poor for foraminal pathology

• Replaced by MRI

MYELOGRAPHYMYELOGRAPHY

• Invasive• 1% spinal headache• Recurrent stenosis• Inability to obtain MRI

MYELOGRAPHYMYELOGRAPHY

MYELOGRAPHY

• Excellent visualization of spinal canal

CT-MYELOGRAPHY

• Excellent for recurrent stenosis

• Invaluable in surgical planning

CT-MYELOGRAPHY

MRI

• Expensive• Patient cooperation• Claustrophobia• Open MRI

EMG-NCS

• Differentiation between neuropathy and radiculopathy

• Acute active denervation vs. chronic denervation

TREATMENT

NONOPERATIVE RX

• Rest

• Analgesic

• Oral steroid

• Physical therapy

• Bracing

• Spinal injection

REST

• Short term activity modification for acute pain

• Long term activity modification is not recommended

ANALGESIC

• NSAIDS• Tylenol• Narcotics• Neurontin

Oral Steroid

• Effective for acute pain

• Short duration therapy

• ? Chronic or repeat tapering dose

PHYSICAL THERAPY

• Avoid extension exercises acutely

• William Flexion Exercises

• Water aerobics• Strengthening of weak

muscle groups

SPINAL INJECTIONS

• Epidural steroid

• Transforaminal root block

• Facet joint injection

EPIDURAL STEROID

• Commonly prescribed• 50% short-term efficacy• Not as selective• May not require

fluroscope

TRANSFORAMINAL ROOT BLOCK

• Highly selective• Diagnostic as well as

therapeutic• Delivers medicine to

the floor of spinal canal

FACET INJECTION

• Facet for back pain• Not for radicular pain• May act as epidural in

40% of cases

SPINAL INJECTION

• Most effective for acute pain

• May not be indicated in cases of acute denervation or progressive motor loss

OPERATIVE TREATMENT

• Decompression of neural element

• Stabilization of unstable segment

“LAMINECTOMY”

DECOMPRESSION OF LATERAL RECESS

• Undercutting the ventral aspect of the facet joints and the associated ligamentum flavum.

• Medial facetectomy if necessary

• The traversing nerve root underneath the facet joint must be visualized

FUSION

• Sagittal instability• Scoliosis• Iatrogenic pars defect• Greater than 50% facet

joint resection

INSTRUMENTATION

Thank you