Lumbar Stenosis

Normal Anatomy

Pathophysiology Refers to a narrowing of the vertebral canal, lateral recesses or intervertebral forearm Commonly caused by degenerative changes Not all individuals with narrowing of spaces are symptomatic Description rather than a diagnosis Pain occurs due to diminished space around the vascular and neural structures of the lumbar spine

root

Mechanism Of Injury Insidious Traumatic Congenital/Inherited Idiopathic (hereditary) Achondroplastic Short/Tbick Pedicles (in lateral stenosis) Acquired Stenosis Degenerative changes (Spondylosis) Ligamentous Hypertrophy (LF or PLL) Facet Joint Hypertrophy Osteophyte formation Disc protrusion Spondylolisthesis Infection Foreign bodies Traumatic Fractures Lumbar Instability

Subjective Presentation will depend on associated pathology Insidious history of back pain Gradual onset of radiating pain in to unilateral or bilateral buttock and extremities Aggravated by positions that reduce space (commonly extension) Leg cramping at night Neurogenic Claudication (different than vascular claudication which worsens on exertion rather than with positions that reduce space)

Objective Presentation depends on associated pathology Pain or limited range with movements that close space (commonly extension) Posture may be kyphotic with reversal of lumbar and cervical curves Possible tightness in posterior musculature of lower extremities Possibly reduced reflexes and sensation changes – commonly originating from L5 nerve root

Differential Diagnosis Cauda Equina Syndrome – immediate onward referral Spinal vascular malformations, tumours, infections – immediate onward referral Non-specific lower back pain (neuro claudication uncommon) Pain originating from hip or knee joint Peripheral neuropathy Ateriovascular Disease (vascular claudication)

Special Tests Kemp’s Test for Lumbar Spine AKA ‘Quadrant Test’ or ‘Extension Rotation Test’ Limited evidence to support diagnostic accuracy May not be appropriate if patient is highly irritable

Further Investigation CT with intrathecal myelography MRI EMG – limited evidence suggesting some accuracy determining symptom severity Axial 3-dimensional image from computed tomography myelography in a patient with severe spinal stenosis. The stenotic pattern (yellow arrow) results from hypertrophic facet joints (black arrow), bulging of disc annulus (white arrow), and thickened ligamentum flavum posteriorly.

Sagittal T1-weighted magnetic resonance image of the spine in discitis Sagittal T1-weighted magnetic resonance image of the spine in discitis. Note the posterior bulging of the vertebral body endplate and disc annulus into the spinal canal (black arrow). The endplates of the disc interspace enhance following an injection of gadolinium diethylenetriamine pentaacetic acid (white arrows), whereas the central abscess within the disc space remains dark (yellow arrow)

General Management Analgesia Gabapentin Activity modification

Conservative Management Manage the underlying pathology (cause/direction of compression) Maintain function as much as possible Address any reversible conditions: obesity, general deconditioning etc. Pain Relief NSAID’s, Ice, Massage Restore Normal ROM Thoracic, Lumbar Restore Normal Neurodynamics Soft tissue techniques, joint mobilisation, nerve sliders Restore Normal Muscular Activation Consider functional deficits VS daily requirements for each individual Use of lumbar support (weight-belt) for symptom modification if necessary

Surgical Management Epidural Corticosteroid injections Posterior Approach Decompressive Laminectomy Decompressive Laminectomy with fusion (for multilevel symptoms) Anterior Approach Discectomy Fusion (for multilevel symptoms)