Cervical Spine Surgery. Orthopaedic Nursing Seminar. Dr Michelle Atkinson. Friday October 21 st Cervical Disc Herniation

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1 Cervical Spine Surgery Dr Michelle Atkinson The Sydney and Dalcross Adventist Hospitals Orthopaedic Nursing Seminar Friday October 21 st 2011 Cervical disc herniation The most frequently treated surgical pathology in the spine Cervical Disc Herniation at any disc level from C2 to the sacrum, most frequently involved are those segments with great range of motion or axial loading forces. C4-5 C5-6 L3-4 C6-7 L4-5 L5-S1

2 Cervical Disc Herniation In the cervical spine, C5-6, C6-7 and C4-5 are the most frequent discs (in that order) to herniate. C4-5 C5-6 L3-4 C6-7 L4-5 L5-S1 Disc Herniation L3-4, L4-5, L5-S1 are most frequently involved in the lumbar spine. Thoracic disc herniation is much less common C4-5 C5-6 L3-4 C6-7 L4-5 L5-S1 Cervical Disc Herniation Protrusions most frequent at posterolateral margins of the disc Central posterior protrusions are often limited by the fibers of the PLL. PLL Disc Anatomy Review The structural changes of disc herniation are not the same as those seen with degenerative disc disease. Disc herniation is thought to be the culmination of a series of acute traumatic events to the disc. The anterior longitudinal ligament (ALL) generally contains anterior and anterolateral protrusions. ALL PLL Nuclear herniation

3 Disc Anatomy Review Four Degrees of Herniation The intervertebral disc is the largest avascularstructure in the body. It receives nutrition by way of passive diffusion through the central vertebral endplates. Because the disc is avascular, it cannot heal itself the way other normal tissues do. Internal disruption and damage to the disc are permanent. arteries veins There are four degrees of disc herniation: Nuclear herniation This occurs when the nucleus ruptures through the innermost fibers of the annulus fibrosus but does not cause any disruption or distortion of the outer annular fibers. Nuclear herniation Four Degrees of Herniation Disc protrusion Also known as a bulging disc, this occurs when the ruptured nucleus distorts the outermost fibers of the annulus causing them to bulge outward. The term prolapsed disc is synonymous with protrusion or bulging. Four Degrees of Herniation Nuclear extrusion This describes a complete split in the annulus that allows nuclear material to leak out into the surrounding spaces. In this type of herniation, the protruded material remains attached to the nuclear material remaining inside the disc. Disc protrusion Nuclear extrusion

4 Four Degrees of Herniation Sequestered nucleus Cervical Disc Herniation Cervical discs are slightly different in anatomical form than lumbar discs: The nucleus is smaller The extruded nuclear substance is no longer attached to the material. remaining inside of the disc. The sequestered fragment(s) may float around the spinal canal and become totally remote from the site from which it originally extruded. Sequestered nucleus well supported on the lateral margins from the uncinate processes. Most occur in the postero-lateral margins Aging decreases the proteoglycan and water content of the disc, more prolapse after the third decade of life. Uncinate processes Major or minor trauma more susceptible to herniation later in life. Nucleus pulposus Herniation Clinical Presentation and Patient Assessment symptoms: neck pain radicular arm pain myelopathy paralysis or paraesthesiae of the upper extremities. Clinical Presentation and Patient Assessment Symptoms may begin abruptly or insidiously. There may be a history of episodes that resolved.

5 Radiographic and Diagnostic Evaluation plain cervical radiographs provide a general assessment of alignment and the extent of degenerative changes. MRI is generally considered the study of choice in evaluating cervical disc herniations CT scan and cervical myelogram occasionally. Discography of the cervical spine Nerve conduction and EMG studies are rarely indicated Large disc herniation Treatment of Cervical Disc Herniations Conservative treatment There is a high likelihood that cervical radiculopathy will resolve without the need for surgery. Treatment of Cervical Disc Herniations Treatment of Cervical Disc Herniations Surgical treatment Continued pain anterior discectomy without fusion, partial anterior discectomy discectomy with fusion posterior laminectomy posterior laminotomy posterior laminoplasty Left foraminal stenosis Left foraminal stenosis caused by an acute herniated cervical disc as seen on axial CT scan. C5 C6 Disc herniation Sagittal MRI confirms herniation at C5-6. Anterior cervical plate

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7 Neurologic Injury to the Spinal Cord Sagittal cross section of a spondylotic spine. This close-up view shows endplate osteophyte (O) and ligamentum flavum (LF) compressing the spinal cord (SC) and leading to complete neurologic loss below the injury. Note the spinal cord hemorrhage (H).

8 Disc Anatomy Review Degenerative disc disease, which is part of the normal aging process, is a long-term process involving all the components of the motion segment. Reduced disc height and motion segment degeneration as a result of the normal aging process.

9 Degenerative Disc Disease This disease is actually a degenerative process of the entire motion segment. Degenerated discs Degenerated disc disease cervical spine C4 C5 Extruded disc material osteophytes Vertebral artery More information Degenerative Disc Disease The following changes to the motion segment may occur from degenerative disc disease: The disc loses water causing it to shrink in volume The disc space begins to narrow. Concurrently, the facet joints begin to override and wear away at the hyaline cartilage surfaces. Compressive loads are transferred away from the nucleus/central endplate interface to the peripheral annulus/vertebral endplate margins Sclerosis of the central endplate further reduces disc nutrition The motion segment becomes hypermobile due to the narrowed space and overriding of the facets Osteophytes develop in an attempt to stabilize excessive motion Osteophytes may encroach on neurological structures Degenerative disc disease may be found in every spinal level. However, the most frequently affected levels by region are: Cervical 5-6 Lumbar 4-5 Lumbar 5-S1 Back The word stenosisis derived from the Greek stenos: narrow, Spinal Stenosis Spinal canal (tube) created by spinal foramina Spinal Stenosis Spinal stenosis can be either developmental or acquired. Developmental forms are present at birth, while acquired forms occur after birth. The most common form of spinal stenosis is the acquired degenerative type. Although stenosis may occur anywhere in the spinal canal, the most frequently involved regions for degenerative spinal stenosis are in the lower cervical and lower lumbar areas. These areas also correlate with the more common sites associated with degenerative disc disease. Thickened ligamentum flavum Central stenosis Stenosis may occur in the central spinal canal (central stenosis) where the spinal cord or Lateral recess stenosis cauda equina are located, in the tract where the nerve root exits the central canal (lateral recess stenosis) or in the lateral foramen (foraminal stenosis) where the individual nerve roots exit out to the body. Foraminal stenosis

10 Spinal Stenosis The actual cause of degenerative spinal stenosis is unknown. However, changes in the three-joint complex of the motion segment are thought to lead to narrowing of the canal and nerve tracts. Degenerative changes may begin in the disc, in either facet joint, or in all three places simultaneously. Eventually, all three joints are involved. Exiting nerve root Osteophyte causing lateral recess stenosis Foraminal stenosis spinal cord Vertebral body Vertebral artery Stenosis of the Cervical Spine One Degeneration unique of the degenerative three-joint complex change is the most noted in the common cervical cause spine of spinal is the stenosis development in the cervical of region. The anatomic changes noted in the cervical osteophytes spine are similar in the to those area of of the the lumbar uncinate spine. These include disc degeneration, hypertrophy of the facet processes. joints, thickening These lateral and redundancy osteophytes of the ligamentum may be flavum and formation of traction osteophytes. a source of pain and they can cause Together, these degenerative changes may lead to compression the development of the of spinal vertebral stenosis artery, which may which be is central, lateral or foraminal. in close proximity to the uncovertebral joint. Obstruction of the vertebral artery may result in reduced circulation to the brain and can lead to fainting spells. Nerve root Spinal cord Axial cross section of stenotic cervical spine osteophytes Thickened ligamentum flavum Radiographic Studies A-P and lateral plain films should be done initially. Oblique films may be helpful in evaluating osteophytes in the foramina. Flexion and extension films can be used to check for segmental instability. CT scan with myelography is excellent for determining lateral recess stenosis. However, MRI is done more routinely as it is not as invasive as myelography and does not expose the patient to radiation. Preoperative radiographic studies showing severe cervical degeneration of C4-5, C5-6, and C6-7. Lateral recess Lateral MRI shows canal stenosis Axial Lateral CT x-ray myelogram reveals at significant C5-6 reveals compromise from disc material significant disc at degeneration canal compromise and anterior with C5-6 and C6-7. lateral bone spurs recess on stenosis C4, C5, and on the C6. right. Degenerated discs Retropulsed Bone spurs disc material Dye in the thecal sac Treatment DECOMPRESSIONsurgery may be done from the anterior, posterior or combined LAMINECTOMYand LAMINOPLASTYare the most common posterior surgical approaches. Conservative Anterior care is generally discectomy, limited with to or individuals without fusion, who sufferradicular is usually done symptoms for single level treatments for degenerative cervical stenosis. Laminectomy involves partial or complete only. stenosis. Non-operative It may treatment also be done options for multiple may include level immobilization lesions. Multiple in level a cervical stenosis removal of the posterior elements allowing increased space for the neural structures. collar, may be Laminoplasty flexibility treated and by is strengthening anterior corpectomy the surgical reconstruction exercises, with pain structural of medications bone the posterior and grafting elements anti-inflammatory and stabilization. that allows agents. Microdiscectomy, with frank either myelopathy open or from through degenerative minimally stenosis invasive shouldbe technique,may considered also be for employed surgical to for Patients increased intervention canal as soon space as but possible. maintains Additionally, the posterior those arch. individuals There are with numerous significant techniques deformity for remove a disc causing a stenosis. Finally, patients who exhibit symptoms of vertebral artery laminoplasty. and/or compression instability may benefit surgical from candidates. a decompression of the offending osteophytes in the uncovertebral joint complex. Cut lamina Lateral view Laminoplas A. Shows spinal cord ty done B. Posterior laminectomy at compression from from those levels allows for ossification of the posterior Notched lamina to form decompression of the spinal posterior longitudinal approach a hinge Superior view cord. ligament at the C4, creating a C5, and C6 levels. hinge on one side of the lamina allowing the Two methods of an anterior opposite corpectomy are illustrated: the lateral view side to shows be a procedure using rongeurs, and the raised axial view shows a burr being used. Either technique away from can be done to decompress the neural the structures. spinal cord. This allows for decompres sion of the central

11 Cervical Stenosis Case Study Bone graft Anterior cervical plate Cervical plate A. B. Posterior lateral (A.) and AP (B.) x-rays of the same patient following a two-level corpectomy (C5 and C6) with structural anterior bone graft and anterior plating C4-C7. The preoperative images can be seen in the Radiographic Evaluation section. Thank You