Cervical Spondylosis

Original Editors - Gertjan Peeters

Top Contributors - Huart Deborah    

Definition/Description

Cervical spondylosis is a chronic degenerative process of the cervical spine that affects the vertebral bodies and intervertebral disks of the neck, and may progress into disk herniation, bone spur formation, compression of the spinal cord, or cervical spondylotic myelopathy.

Possible characteristics are:

•  Degenerative_Disc_Disease Formation of osteophytes
•  Facet and uncovertebral joint arthritis
•  Ossification of the posterior longitudinal ligament
•  Hypertrophy of the ligamentum flavum causing posterior compression of the cord especially as it buckles in extension;
•  Spinal stenosis Degenerative subluxation of cervical vertebra;
•  Dislocated fragment of annular cartilage compressing the spinal cord or nerve root
  

In some cases this degeneration also leads to a posterior protrusion of the annulus fibres of the intervertebral disc, causing compression of the nerve roots, pain, motor disturbances such as muscle weakness, and sensory disturbances. As the spondylosis progresses there may even be interference with the blood supply to the spinal cord where the vertebral canal is at its most narrow.

Clinically Relevant Anatomy

The cervical spine is made up of seven segments and is highly mobile. It performs 3 important functions; it forms the structural support for the head, protects the cervical spine cord and the exiting nerve roots enclosed within it. There is an important distinction between the high and mid cervical regions and the lower cervical region. The first two vertebrae, the atlas and axis, are anatomically and functionally different segments. The atlas is a uniquely shaped ring without a vertebral body, it articulates with the skull at the atlanto-occipital joint and allows for approximately 50% of the flexion and extension movements of the neck. It pivots on the odontoid process of the axis, which arises from the superior surface of the latter’s body. The atlanto-axial joint is responsible for approximately 50% of the rotational movement in the neck.(41) (Level of Evidence: 5) There is no intervertebral disc between C0-C1 and C1-C2. The lower five cervical vertebrae are roughly cylindrical in shape with bony projections . The intervertebral discs act as shock absorbers, stabilisers and allow the spine to be flexible.

The sides of the vertebrae are linked by small facet joints. Strong ligaments attach to adjacent vertebrae to give extra support and strength. We can split the cervical spine in three columns; anterior, middle and posterior part.

• Anterior: consists of the longitudinal anterior ligament , the annulus of the disc and the anterior part of the corpus vertebrae
• Middle: consists of the longitudinal posteriorligament , the posterior part of the annulus and the corpus vertebrae.
• Posterior: All the structures that are posteriorly positioned compared to the longitudinal posterior ligament.

Epidemiology /Etiology

Cervical Spodylosis can lead to different conditions ranging from axial neck pain to cervical myelopathy. It is the most common cause of nontraumatic myelopathy, resulting in paraparesis and quadriparesis. The incidence of neck pain in adults is approximately 20-50% per year, much of which is caused by spondylosis. (41) (Level of Evidence: 5) The prevalence of cervical spondylosis is similar for both sexes, although the degree of severity is greater for males. Approximately 95% of people by the age of 65 will have a degree of cervical spondylosis, the most prevalent spine dysfunction in elderly people. It has been estimated that 75% of persons over the age of 50 have a narrowing of the spinal canal or intervertebral foramina, and 50% of these cases are symptomatic.By age 65 that incidence increases to 75%. Spondylotic changes in the cervical spine occur at singular disc space levels in 15-40% of patients and at multiple levels in 60-85%. The discs between the 3rd and 7th cervical vertebrae are most commonly affected. Repeated occupational trauma may contribute to the development of cervical spondylosis. An increased incidence has been noted in patients who carried heavy loads on their heads or shoulders, dancers, gymnasts, and in patients with spasmodic torticollis, although this cause is not widely accepted. In about 10% of patients, cervical spondylosis is due to congenital bony anomalies, blocked vertebrae, malformed laminae that place undue stress on adjacent intervertebral discs.

Characteristics/Clinical Presentation

Symptoms can depend on the stage of the pathological process and the site of neural compression.Diagnostic imaging may show spondylosis, but the patient may be asymptomatic  Pain, paresthesias or muscle weakness, or a combination of these are the most commonly reported symptoms. McCormack et al  reported that intermittent neck and shoulder pain is the most common syndrome seen in clinical practice. Due to cervical radiculopathy, the pain most often occurs in the cervical region, the upper limb, shoulder, and/or interscapular region . In some cases the pain may be atypical and manifest as chest or breast pain, although it is most frequently present in the upper limbs and the neck. Chronic suboccipital headache could also be a clinical syndrome in patients with cervical spondylosis, which may radiate to the base of the neck and the vertex of the skull. Central cord syndrome may also be seen in relation to cervical spondylosis and in some cases dysphagia or airway dysfunction has been reported to be related cervical spondylosis.  Cervical spondylosis can also often cause cervical spondylotic myelopathy. 

Differential Diagnosis

• Other non-specific neck pain lesions - acute neck strain, postural neck ache or Whiplash, Fibromyalgia and psychogenic neck pain;
• Mechanical lesions - disc prolapse or diffuse idiopathic skeletal hyperostosis;
• Inflammatory disease - Rheumatoid arthritis, Ankylosing spondylitis or Polymyalgia rheumatica, Metabolic diseases - Paget's disease, osteoporosis, gout or pseudo-gout, Infections - osteomyelitis or tuberculosis, Malignancy - primary tumours, secundary deposits or myeloma;
  
• Adhesive Capsulitis in Physical Medicine and Rehabilitation;
• Brown-Sequard Syndrome;
• Carpal Tunnel Syndrome;
• Central Cord Syndrome;
• Cervical Disc Disease;
• Cervical Myofascial Pain;
• Cervical Sprain and Strain;
• Chronic Pain Syndrome;
• Diabetic Neuropathy;
• Multiple Sclerosis;
• Neoplastic Brachial Plexopathy;
• Osteoporosis and Spinal Cord Injury;
• Physical Medicine and Rehabilitation for Myofascial Pain;
• Radiation-Induced Brachial Plexopathy;
• Rheumatoid Arthritis;
• Traumatic Brachial Plexopathy. 

Diagnostic Procedures

Cervical spondylosis is often diagnosed on clinical signs and symptoms alone.

Signs:

• Poorly localised tenderness
• Limited range of motion, forward flexion, backward extension, lateral flexion, and rotation to both sides
• Minor neurological changes, such as inverted supinator jerks (unless complicated by myelopathy or radiculopathy.

Symptoms:

• Cervical pain aggravated by movement
• Referred pain
• Retro-orbital or temporal pain
• Cervical stiffness
• Vague numbness, tingling or weakness in upper limbs
• Dizzyness or vertigo
• Poor balance
• Rarely, syncope, triggers migraine.

Diagnostic imaging such as X-ray, CT, MRI, and EMG can also be used to confirm a diagnosis. C. Xu et al found that MRI can reliably determine the presence or degree of facet tropism, but not facet arthrosis. It is, therefore, advisable to augment CT with MRI for an accurate diagnosis.

Outcomes Measures

Visual analogue scale (VAS)

Short Form 36 (SF-36)

Neck Disability Index (NDI).

Spondylotic changes may result in direct compression and ischemic dysfunction of the spinal cord. Several clinical measures of disease severity have been developed such as the Japanese Orthopaedic Association (JOA) and the Nurick Classification scoring systems. These popular scales have been developed to quantify the extent and progression of this disease.

Test's such as Spurling’s test (A) and Bakody’s test (shoulder abduction release test B) can be used to differentiate between shoulder disorders and cervical spondylosis.

Examination

Muscle atrophy is assessed on the affected side in the upper limb, shoulders and scapular regions and compared with the unaffected side. Muscle strength is tested in 4 muscles representing the myotomes C5-C8. Anterior, middle, and posterior parts of the deltoid muscle are tested by resisting flexion, abduction, and extension of the humerus. Strength of biceps brachii is assessed by resisted elbow flexion when the forearm is supinated. Triceps brachii muscle strength is tested by resisted elbow extension from 90 degrees of elbow flexion. The dorsal interosseus muscles are tested by resisting the separation of the 2nd through 5th fingers. Sensitivity to light touch and to pain are also tested for the relevant cervical dermatomes.

Medical Management 

Cervical spondylosis is more often seen as a chronic condition, but in most cases it is not progressive and only in rare cases is surgery required. Initial management should be nonoperative.

There are various medications used to treat cervical spondylosis:

• Non-Steroidal Anti-Inflammatory Drugs (NSAID’s) although is an absence of clinical trials for the use of NSAIDs in the treatment of cervical spondylosis, but in theory they will reduce inflammation around the nerve, decreasing its sensitivity to compression.

• Opioid analgesics. The use of opoid analgesics has been limited/reduced because of the ineffectiveness in neuropathic pain, yet despite this, there is evidence that oxytocyne can be effective in the treatment of cervical spondylosis.

• Muscle relaxants. The use of muscle relaxants is effective for any associated spasm of the trapezius muscle, but the treatment duration is relative short, lasting for a maximum of two weeks.

• Corticosteroids There is limited evidence to support the use of systemic corticosteroids in the treatment of cervical spondyolosis.
  

Poor prognostic indicators and absolute indications for surgery are:

• Progression of signs and symptoms;
• Presence of myelopathy for six months or longer;
• Compression ratio approaching 0,4 or transverse area of the spinal cord of 40mm squared or less.
  

The goals of surgical treatment of cervical spondylosis are:

• Improvement or preservation of neurological function;
• Prevention or correction of spinal deformity;
• Maintenance of spinal stability.

Decompression may be achieved using an anterior, a posterior, or a combined approach. Recommended decompression is anterior when there is anterior compression at one or two levels and no significant developmental narrowing of the canal.

Anterior decompression, the different surgical options:

• Anterior cervical foraminotomy
• Anterior cervical discectomy without fusion
• Anterior cervical discectomy with fusion
• Cervical arthroplasty

For compression at more than two levels, developmental narrowing of the canal, posterior compression, and ossification of the posterior longitudinal ligament, posterior decompression is recommended: Posterior laminoforaminotomy/foraminotomy and/or discectomy

Physical Therapy Management

• There is little evidence for using exercise alone or mobilisation and/or manipulations alone.
• Mobilisation and/or manipulations in combination with exercises are effective for pain reduction and improvement in daily functioning in sub-acute or chronic mechanical neck pain with or without headache.
• There is moderate evidence that various exercise regimens, like proprioceptive, strengthening, endurance, or coordination exercises are more effective than usual care (analgesics, non-steroïdal anti-inflammatory drugs, or muscle relaxants)

Typically, treatment requires 15–20 sessions over a 3-month period. The treatment should individualised, but generally includes isometric exercises, proprioceptive re-education, manual therapy and postural education.

Manual therapy is defined as high-velocity; low-amplitude thrust manipulation or non-thrust manipulation.
Manual therapy of the thoracic spine will be used for reduction of pain, improving function, to increase the range of motion and to address the thoracic hypomobility

Thrust manipulation of the thoracic spine could include techniques in a prone, supine, or sitting position based on therapist preference. Also cervical traction can be used as physical therapy to enlarge the neural foramen and reduce the neck stress

Non-thrust manipulation included posterior-anterior (PA) glides in the prone position. The cervical spine techniques could include retractions, rotations, lateral glides in the ULTT1 position, and PA glides. The techniques are chosen based on patient response and centralisation or reduction of symptoms.

Postural education includes the alignment of the spine during sitting and standing activities.

Thermal therapy provides symptomatic relief only and ultrasound appears to be ineffective. Other methods such as infrared radiation, interferential therapy and massage can also be used in the treatment of cervical spondylosis.

Soft tissue mobilisation was performed on the muscles of the upper quarter with the involved upper extremity positioned in abduction and external rotation to pre-load the neural structures of the upper limb.

	- The therapist places his upper chest at the level of the patient’s middle thoracic spine, takes the patient’s elbows and pulls them towards themselves until the spine is firmly positioned against the their upper chest
	- The patient takes the patient's neck into both hands. - The patient’s arms are pulled downward to create spinal flexion down to the level the therapist wants to manipulate - The therapist stabilises the inferior vertebra - The therapist pushes through the patient’s arms
	- The patient clasps the back of their head with both hands. - The patient’s arms are pulled downward to create spinal flexion down to the level the therapist wants to manipulate. - The therapist uses their chest to stabilise and perform the manipulation of the targeted motion segment and uses their body to push down through the patient’s arms.

Home Exercices 

Exercises include cervical retraction, cervical extension, deep cervical flexor strengthening, scapular strengthening, stretching of the chest muscles via isometric contraction of flexor of extensor muscles to encourage the mobility of the neural structures of the upper extremity.

cervical Retraction Exercise	The patient retracts their head as far as comfortably possible with head and eyes remaining on the same level.
cervical extension exercises	The patient retracts the cervical spine, lifts the chin up, and extends the cervical spine to end range. Then 2-3 small right to left oscillations of the head are performed. The head is returned to the midline position, the chin tucked under and then return to the retracted position.
Deep neck flexor exercises	The patient nods the head and flattens the spine without pushing the head back into the table, with minimal activation of the sternocleidomastoid muscle during the deep neck flexor contraction.
Scapular strengthening exercises	Squeeze the shoulder blades together with or without resistance (seated or standing), without shrugging the shoulders (activating the upper trapezius muscle) during the exercise

Clinical Bottom Line

Cervical Spondylosis is a degenerative disorder at the level of the cervical spine. It can be described as the result of degeneration of the intervertebral discs or the corpus vertebrae in the cervical region. It is the most common cause of nontraumatic myelopathy, resulting in paraparesis and quadriparesis. The incidence of neck pain in adults is approximately 20-50% per year, much of which is caused by spondylosis. Approximately 95% of people by age 65 have cervical spondylosis to some degree, it’s the most common spine dysfunction in elderly people. The symptoms can depend on the stage of the pathologic process and the site of neural compression. On imaging studies you can see that there is a spondylosis, but the patient can’t have any symptoms at all. Most of the time cervical spondylosis is diagnosed on clinical signs and symptoms alone. C. Xu et al found that MRI can reliably determine the presence or degree of facet tropism, but not facet arthrosis. Therefor, it is advisable to augment CT with MRI for an accurate diagnosis. Surgical intervention is only in rare cases required, it should be chosen with great care. The treatment should be tailored to individual patients but includes supervised isometric exercises, proprioceptive reeducation, manual therapy and posture education.

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