Spondylosis: any or various degenerative diseases of the spine Myelopathy: any disease or disorder of the spinal cord or bone marrow Radicular: of, relating to, or involving a nerve root Radiculopathy: any pathological condition at the nerve roots. Definitions of Spinal Disorders
A non-specific term Refers to any lesion of cervical spine of a degenerative nature (non-inflammatory disc degeneration) Cervical Spondylosis
Imbalance between formation & degradation of proteoglycans & collagen in disc With aging, a -ve imbalance with subsequent loss of disc material -> degenerative changes Factors influencing severity of degeneration Heredity Trauma Metabolic Other environmental effects, eg. smoking Pathology
Degeneration -> Disc herniation Stenosis Instability Spine unable to withstand physiologic loads -> significant risk for neurologic injury, progressive deformity & long-term pain & disability Not common in cervical spondylosis except those with stiffness in middle & lower segments who develop compensatory hypermobility at C3-4 or C4-5 -> myelopathy
Cervical spinal instability Radiographic criteria of White >11o angulation >3.5 mm translation of adjacent subaxial segments
Most people with degenerative changes of the cervical spine remain asymptomatic. Symptomatic patients are usually older than 40 years of age and present with symptoms that are caused by the compression of neural structures. There are three main symptom complexes related to cervical spondylosis: 1.Neck pain 2.Cervical radiculopathy 3.Cervical myelopathy Presentation
Narrowing of intervertebral disc Sclerosis of endplates Osteophyte formation
Similar changes may occur in facet joints
Most frequently in C5-6 & C6-7
Incidence of spondylosis on X-rays in asymptomatic patients
80% in 51-60 age group 95% in 61-70 age group Radiological findings
Incidence of Spondylosis on MRI in asymptomatic patients
A condition caused by compression of a nerve root in cervical spine. Involves a specific spinal level with sparing of levels immediately above & below. Peak age:50-54 year Disc protrusion =22% spondylosis=68% 41% had associated lumbar radiculopathy Cervical Radiculopathy
C7 monoradiculopathy-most common,C6-7 level. Pain post. aspect of arm, posterolateral forearm,middle finger Tricep and fingers extensor weakness Tricep reflex reduce. 90% not treated surgically were asymptomatic. Cervical Radiculopathy
C3 radiculopathy-involving C2C3 disk. Uncommon Sensory-post.neck,suboccipital and ear No detectable muscle motor. C4 radiculopathy-neck and shoulder pain No significant motor deficit. Radiating pain-base of the neck,midshoulder and scapula. No reflex changes. Radiculopathy
C5 :deltoid muscle- difficulty in elevating of arm. Weakness of supraspinatus-infraspinatus Decrease bicep reflex C6:herniation bt.C5C6. top of neck,along the bicep into lat. Aspect of the forearm and onto dorsal surface of hand between thumb and index finger. Bicep and brachoradialis reflex decrease.
C8 radiculopathy-numbness small finger and medial half of the ring finger. Most of intrinsic muscles of the hand. Lose fine fingertip and grip strength.
Largely secondary to mechanical compression of nerve roots. 5 articulations: intervertebral disc 2 uncovertebral 2 facets joints Patho-anatomy
Innervation of the cervical intervertebral disc ST=cervical sympathetic trunk VA=vertebral artery; ALL=anterior longitudinal ligament PLL=posterior longitudinal ligament SVN=cervical sinuvertebral nerve
Half of adult population will experience neck and radicular pain. Rarely progressed to myelopathic state (Less and Turner, 1963) Natural history
Varies greatly-Pain, paraesthesia and weakness. Classically:significant radicular pain and refered trapezial and periscapular pain. Only 55% had pain in a strictly radicular pattern.(Henderson et al,1983,neurosurgery). Other studies:60%-70% motor weakness,70% reflex changes. Often described symptoms that correlate with various head position. Clinical features
Exacerbation with neck hyperextension and tilted toward affected side. Modified spurling test(combination of head extension and head tilt) Shoulder abduction relief sign-specific for soft disc herniation. Symptoms and examination
Acute-disc herniation:Posterolateral, mid-line and intra-foraminal Insidious-degenerative Uncovertebral-compress nerve root anteriorly. Neuroforaminal narrowing by:osteophytes superior facet, decrease disc height Cervical disc herniation and degenerative spondylosis
Indications: significant pain or deficits after 6 weeks or progressive neurologic deficits Approach should be determined by position & type of lesion Soft lateral discs easily removed by posterior approach Spurs & more paramedian discs via anterior approach Surgical procedures
Anterior cervical discectomy & fusion
Anterior foraminotomy (Jho’s procedure)
Posterior cervical foraminotomy For unilateral osteophytes, facet hypertrophy, extruded disc causing unilateral radiculopathy Avoids bone fusion but often does not efficiently eliminate the herniated disc materials
Indications for this approach:
Progressive or persistent symptoms arising from unilateral or bilateral lateral disc herniations
Spondylotic neural foraminal compromise at one to two levels.
Sacrifice the spinal motion at the herniated disc level.
C/I-congenital stenosis, stenosis arising predominantly from posterior structures, and disease at greater than three levels
ANTERIOR CERVICAL DISCECTOMY AND FUSION
provides an effective elimination of the compressing herniated portion of the disc or bone spurs, while preserving the remaining disc between the vertebrae and maintaining spinal motion Anterior cervical microforaminotomy(Jho procedure)
Myelopathy = Cord dysfunction Cervical Spondylitic Myelopathy (CSM) introduced by Brain et. al. 1952. CSM= gait abnormality and weakness or stiffness of the legs which usually develop insidiously. > 50% CM are CSM. Other causes for myelopathy are trauma, tumour and congenital. Cervical Myelopathy
Pathology 1.Developmental stenosis: AP diameter of spinal canal of 12 mm or less . 2.Dynamic stenosis: defined as Penning’s jaw diameter - distance from posterior inferior corner of vertebral body, to anterior margin of subjacent lamina, 12 mm or less, a/w 2 mm of retrolisthesis with neck in extension 3.Disc herniation 4.Segmental OPLL (Ossification of posterior longitudinal ligament) 5.Continuous OPLL 6.Posterior spur 7.Calcification of ligamentum flavum (CLF): tends to occur in elderly women
1 & 2 most common
Cervical Myelopathy(Static stenosis)
Pain usually absent.
Discomfort varies from aching to
Gait disturbances,clumsy hands,
spasticity,sphincter disturbances, motor weakness. Cervical Myelopathy
The proximal motor groups of the legs are more involved than the distal groups (which is the opposite of the pattern with lumbar stenosis) Clinical Presentation
Hyperreflexia, positive Hoffmann’s sign, Babinski test, clonus, sensory and motor changes. Myelopathic hand syndrome: thenar atrophy, positive finger escape sign and grip release test. Positive Lhermitte’s sign: electric shock sensation with neck flexion Physical findings
Many patients have evidence of significant compression on neuroradiologic imaging but are relatively asymptomatic No patient ever return to normal state. 75% episodic worsening. 20% slow and steady progression. 5% rapid onset with lengthy disability. Myelopathy rarely developed in patient with spondylosis. Generally, once moderate signs and symptoms of myelopathy develop,the ultimate prognosis is poor. Cervical Myelopathy:natural history
Scapulohumeral reflex. (tap on scapula spine-pathology above C4) L’Hermitte’s sign. (flexion on neck Paresthesia / shock down to extremities) Babinski sign. Cervical Myelopathy(signs)
Plain X-ray for stenosis Normal = ~17 mm Absolute (AP canal diameter <10 mm) or relative (10-13 mm) stenosis are risk factors for myelopathy, radiculopathy, or both Pavlov's ratio (canal/vertebral body width) Should be 1.0, with <0.85 indicating stenosis Ratio of <0.80 is a significant risk factor for lateral neurologic injury This identifies a congenitally narrow canal OPLL
MRI Shows cervical disc prolapse well Demonstrates spinal cord well High intensity signal can be found in spinal cord on T2, representing myelomalacia (necrosis/cavity formation) CT shows OPLL & bone spurs best
Brown-Sequard syndrome. Unilateral cord lesion. Cross motor and sensory dysfunction. Cervical Myelopathy(clinical syndromes)
Central cord syndrome. Typically Upper limbs are more affected than lower limbs. Cervical Myelopathy(clinical syndromes)
Motor system syndrome. Anterior cord syndrome. Spinal thalamic tract. Cortical spinal tract. Minimal sensory complaints. Cervical Myelopathy(clinical syndromes)
May display findings such as slight gait disturbance and mild hyper-reflexia but may have no functional deficits and no weakness.
Re-evaluation every 6 to 12 months to look for deterioration of neurologic function or a change in symptoms.
Muscle relaxants Analgesics NSAID Physiotherapy Cervical support Conservative management
Absolute indication = neurological deficit which is progressing Patients with cord compression on MRI but no objective symptoms or findings of myelopathy best treated non-operatively
Herniation shows better improvement after surgery, older patients & those with dynamic stenosis show less improvement.
Indications for surgery
Surgical approaches No controlled prospective studies comparing anterior & posterior approaches Approach depends on Location of pathology Levels of involvement Stability of spine Presence of kyphotic deformity
Indications: Generally recommended if disc herniation or posterior spur causing compression at 1 or 2 levels Also indicated if there is kyphotic deformity, so that correction can be achieved Options: Anterior discectomy & interbody fusion with anterior spinal instrumentation With more extensive anterior decompression involving excision of osteophytes - discectomy & corpectomy with strut graft fusion Anterior Decompression & Fusion
Ant. Corpectomy strut grafting better decompression kyphotic deformity more problem if >3 level Operative management
Generally recommended if there is compression of spinal cord at 3 levels or more, in developmental stenosis or calcification of ligamentumflavum Options Laminoplasty Directly decompresses cord posteriorly & indirectly decompresses cord anteriorly Requirements Straight or lordotic cervical spine Stable spine Multilevel cord compression
Laminectomy - poor outcome due to spinal instability & kyphosis
Posterior decompression +/- fusion
Canal expansive laminoplasty decompression of spinal canal with reduced risk for kyphotic deformity No fusion Z-plasty (Hattori) Hemi-lateral open (Hirabayashi) Bilateral open (Kurokawa)
Cervical Myelopathy(evaluation) < 7 = severe 8-12 = moderate 13-16 mild Max = 17