Do you want to get relief of your Lower Back Pain ?

SPINAL CANAL STENOSIS

Spinal canal stenosis is narrowing of the spinal canal and the consequent compression of the cord and the nerve roots. It may affect the cervical thoracic or lumbar spine.

Canal stenosis is common in lumbar vertebrae. One or more roots of the cauda equina may be affected due to the constriction in spinal canal before it exits through the foramen. This condition was first described by Portal in 1803.

LUMBAR CANAL STENOSIS

Lumbar canal stenosis is a cauda equina compression in which the lateral or anteroposterior diameter of the spinal canal is narrow with or without a change in the cross-sectional area. The nerve root canals and the IV foramen may also be narrowed.

Patient may present with low backache, neurological symptoms in the lower limbs and bladder, bowel dysfunctions in extreme cases

CLASSIFICATION

1. Generalized/localized
2. Segmental (local area of each vertebral spinal segment is affected).

• Central
• Lateral Recesses
• Foraminal
• Far Out

3. Anatomical area:

• Cervical (seen)
• Thoracic(rare)
• Lumbar (most common)

CAUSES

1. Pathological:

• Congenital , For Example. Achondroplasia
• Acquired- degenerstive , iatrogenic, and spondylitic.

2. Other Causes:

• Paget’s Disease
• Flurosis
• Kyphosis
• Scoliosis
• Fracture Spine
• DISH (Diffuse idiopathic skeletal hyperostosis) syndrome.

3. Latrogenic causes ,For Example, hypertrophy of posterior bone graft, incomplete treatment of stenotic condition, etc.

Degenerative lumbar disk disease leading to thickening and narrowing of the spinal canal is the most common cause.

CLINICAL FEATURES

Lumbar canal stenosis is common in males above 50 years. Usually, the symptoms are fewer in number, but the patient may complain of low backache.

Cauda equina claudication is the common symptom. Here, the patient complains of pain in the buttocks and legs after walking, which decreases sitting, rest and forward bending. Patient may complain of hypoesthesia and paresthesia. Usually, the patient finds no problem walking uphill or riding a bicycle. Nerve root entrapment in the lateral recess causes claudication and sciatica.

INVESTIGATIONS

Radiographs of the lumbar spine consisting of AP, lateral and oblique views are recommended. However radiology may not show stenosis. The following points are looked for:

• Reduced interpedicle distance.
• AP or midsagittal diameter of the affected vertebra (Normal-15 mm), absolute midsagittal diameter of the canal is decreased.
• Measurement of the lateral sagittal diameter.
• Hypertrophy and sclerosis of the facet joints.
• Reduced interlaminar space and short, stout spinous process.
• Associated features like presence of listhesis, prolapsed disk, osteophytes, etc.

TREATMENT

Conservative Methods

This aims at symptomatic relief of pain.

• Drug therapy like the NSAIDs, etc.
• Epidural steroids may help in some cases.
• Physiotherapy with heating modalities helps.
• Pelvic traction may help relieve compression.
• Exercises:  General  conditioning  exercises like walking, swimming   and   flexion-oriented exercises are  useful.
• Deweighted Treadmill Ambulation: This consists of applying vertical traction with a harness  while doing the treadmill  exercises. This offers twin benefits of both exercises and traction.
• Belts and corsets (soft): These  may  offer  some relief.

Surgical Methods

Most of the surgical methods described for lumbar canal stenosis aim at decompressing the constricted lumbar canal. Laminectomy is useful in central canal stenosis. Diskectomy and osteotomy of inferior articular process to remove the hypertrophic elements help.

For lateral canal stenosis laminotomy, disk excision, partial medial facetectomy and foraminotomy help. Spinal fusion to stabilize the lumbar spine is usually not required as instability is less commonly seen in lumbar canal stenosis.

It should be noted that neurogenic claudication responds poorly to the conservative treatment but responds well to surgical decompression.