HISTORY

It is important to ascertain the relationship of the present symptoms to any previous neck disorder. Has there been any previous injury to the neck? Or a sudden jerk of the head that might have jarred the cervical spine? Is there a history of ‘stiff neck’ – a common feature in the early stages of prolapsed cervical disc?

If pain in the upper limb is an associated symptom, it is important to determine its exact distribution. Pain caused by pressure upon a nerve root in the cervical region follows a clearly defined course which depends upon the particular nerve root involved, and it is usually severe. It commonly extends down the upper arm into the forearm and hand, radiating to one or more of the fingers. It is often accompanied by paraesthesiae, described as ‘pins and needles’ or ‘numbness’. In contrast, pain referred down the limb from a lesion of the shoulder or humerus is more diffuse and ill defined, and it seldom extends below the elbow.

EXPOSURE

The patient must be stripped to the waist. Preferably he should stand, or he may sit upon a stool.

STEPS IN CLINICAL EXAMINATION

A suggested routine for clinical examination of the neck is summarised in Table 12.1.

Table 12.1 Routine clinical examination in suspected disorders of the neck

DEFORMITY

The cervical spine normally has a slight anterior curvature (lordosis). Straightening of this curve, or an angulation in the reverse direction (kyphosis), is sometimes significant and may suggest an underlying abnormality. Any lateral or rotational deformity (torticollis) must also be noted.

MOVEMENTS

The movements to be examined are flexion, extension, lateral flexion to right and left, and rotation to right and left (Fig. 12.1). Flexion–extension movements occur mainly at the occipito-atlantoid joint but to some extent throughout the cervical spine. Lateral flexion takes place throughout the cervical spine. Rotation occurs largely at the atlanto-axial joint, with a small range of movement at the other joints. It is important to find out whether movement causes pain and, if so, whether the pain is felt locally in the neck or whether it is referred down the upper limbs. It should be noted also whether movement is accompanied by audible or palpable crepitation.

Fig. 12.1 Normal movements of the cervical spine in A flexion and extension, B lateral flexion and C rotation.

NEUROLOGICAL EXAMINATION OF UPPER LIMBS

This is an essential step in the investigation of the neck because cervical lesions so often interfere with the brachial plexus.

Muscular system. The muscles of the shoulder girdle, arm, forearm, and hand must be examined for wasting or fasciculation, a comparison being made on the two sides. The tone and power of each muscle group are then tested in turn and a comparison is made with the opposite limb. It is worth remembering the major root innervation for each muscle group when testing; C5 to deltoid, C6 biceps and wrist extensors, C7 triceps and wrist flexors, C8 finger flexors, and T1 to intrinsic muscles of hand.

Sensory system. Examine the patient’s sensibility to touch and pin prick. In appropriate cases test also the sensibility to deep stimuli, joint position, vibration, and heat and cold. The nerve roots supplying the sensory dermatomes in the upper limb are shown in Fig. 12.2. In the assessment of sensory loss it should be remembered that the middle or long finger, representing the central axis of the limb, is innervated mainly from the seventh cervical nerve. The radial half of the hand is innervated by the proximal roots of the brachial plexus (C5, C6) whereas the ulnar half is innervated from the more distal roots (C8, T1).

Fig. 12.2 Dermatomes of the upper limb. A knowledge of these in testing sensory impairment will assist in determining the level of root involvement in cervical spine disease.

Sweating. Feel whether the digits are moist or dry. Sweating is dependent upon intact sudomotor nerve fibres.

Reflexes. Compare on the two sides the biceps jerk (mainly C6), the triceps jerk (mainly C7), and the brachioradialis jerk (mainly C6).

From the findings elicited it should be possible to determine whether there is a neurological disturbance and, if so, whether it is of upper or lower motor neurone type, and the identity of the roots, trunks, or branches involved.

VASCULAR EXAMINATION OF THE UPPER LIMB

The subclavian artery is sometimes interfered with by a lesion of the neck. The efficiency of the circulatory system in each upper limb must therefore be determined. Judge and compare on the two sides the colour and warmth of the forearm, hand and fingers. Test and compare the radial pulses, first with the limb at rest, then with the shoulder depressed and the head rotated towards the side examined.

EXTRINSIC CAUSES OF NECK SYMPTOMS

Occasionally neck symptoms have their origin outside the neck itself. Thus pain may be referred to the neck from the ears or throat. These sites should be examined routinely for evidence of disease.

Symptoms in the upper limb that might suggest the possibility of a neck disorder involving the brachial plexus may in fact have their origin in the shoulder or elbow, or at any point along the peripheral distribution of the nerve trunks.

DIAGNOSTIC IMAGING

Radiographic examination. Routine radiographs of the cervical spine include an antero-posterior and a lateral projection. Additional projections are often required when it is desired to show a particular structure more clearly. For a study of the dens (odontoid process) of the axis a special antero-posterior projection is made through the open mouth. Occasionally oblique projections are required for a proper investigation of the intervertebral foramina and the facet joints, and is also valuable in revealing the size and shape of a cervical rib.

Other techniques of imaging. Magnetic resonance imaging (MRI) is used increasingly to demonstrate the relationship between the bony and neurological structures in the cervical spine. Computerised tomography (CT scanning) and radioisotope scanning may sometimes be required to demonstrate pathological changes in the bony structures.

INFANTILE TORTICOLLIS (‘Congenital’ torticollis; muscular torticollis)

In infantile torticollis (wry neck) the head is tilted and rotated by contracture of the sternomastoid muscle of one side. Strictly this is not a true congenital deformity because it arises after birth. With improvements in obstetrical practice it is now seen much less often than it was in the past.

Cause. This is uncertain. Probably there is interference with the blood supply of the sternomastoid muscle, caused by injury during birth.

Pathology. In the established condition, part of the affected muscle is replaced by contracted fibrous tissue. In some cases contracture is known to have been preceded, in early infancy, by a tumour-like thickening of the muscle (‘sternomastoid tumour’), the histology being that of muscle infarction and replacement by fibrous tissue.

Clinical features. The child, often between 6 months and 3 years old when brought for consultation, is noticed to hold the head on one side. On examination, the contracted sternomastoid muscle is felt as a tight cord. The ear on the affected side is approximated to the corresponding shoulder. In long-established cases there is retarded development of the face on the affected side, with consequent asymmetry (Fig. 12.3).

Fig. 12.3 Infantile torticollis. Note the tense cord-like left sternomastoid muscle and the facial asymmetry.

Diagnosis. The condition has to be distinguished from other forms of wry neck, including structural deformities of the cervical spine, ocular torticollis, muscle spasm from a local inflammatory lesion such as infected glands, and psychogenic (hysterical) torticollis. The important diagnostic features are the history, the cord-like contracted sternomastoid muscle, and the facial asymmetry. Imaging of the spine with plain radiographs is important to exclude any underlying vertebral abnormalities or subluxations.

Treatment. If the condition is seen at the stage of ‘sternomastoid tumour’, repeated stretching of the muscle under the supervision of a physiotherapist is effective. In established cases the contracted muscle should be divided at its lower attachment. After operation corrective exercises should be encouraged.

CONGENITAL SHORT NECK (Klippel–Feil syndrome)

This is an uncommon non-familial congenital malformation of the cervical spine characterised clinically by short neck and limitation of head movements. The cause is unknown.

The degree of abnormality varies widely. The bony deformity consists in fusion of two or more of the cervical vertebrae. Clinically, the neck appears short or absent, and the hair-line is low. The neck may also be webbed to the shoulder. Movements of the head are restricted. Radiographs show the underlying bony abnormality, but operation is seldom indicated.

CONGENITAL HIGH SCAPULA (Sprengel’s shoulder¹)

Congenital high scapula is an uncommon congenital deformity characterised by an abnormally high position and relative fixity of the scapula. The cause is unknown. The anomaly represents a failure of the scapula – originally a cervical appendage – to descend during development to its normal thoracic position. The scapular muscles are ill developed and may be represented only by tough fibrous bands.

Clinically, the scapula on one or both sides is abnormally high. Its attachments seem almost rigid and it does not rotate freely during abduction of the arm. The range of shoulder abduction is consequently impaired, but the functional disability is slight.

Treatment. The condition is often best left alone, but some cases are suitable for operation. The upper part of the scapula (above its spine) is excised after division of the contracted levator scapulae muscle and of tight fascial bands. The blade of the scapula is then divided vertically throughout its length near the vertebral border. This allows the main (lateral) part of the scapula to be displaced downwards relative to the medial strip, and the two parts are re-united with sutures through drill holes.

CERVICAL SUBLUXATION AND DISLOCATION (Spontaneous subluxation of the cervical spine; cervical spondylolisthesis)

Most displacements of the cervical spine are caused by injury, but in some circumstances there may be spontaneous displacement, usually forwards, of a cervical vertebra upon the one next below it.

Causes and pathology. There are three types, caused by:

Congenital or acquired non-fusion of dens. Occasionally the dens fails to fuse with the body of the axis by bone, being attached only by fibrous tissue (os odontoideum). Under the constant stress of superimposed weight the fibrous bond slowly stretches, allowing the dens, and with it the atlas and skull, to slide gradually forwards upon the axis (Fig. 12.4A). A similar condition may exist after fracture of the dens, but this would be preceded by a history of trauma. Instability may also be present in patients with Down’s syndrome and radiological screening may be indicated in patients with this condition.

Fig. 12.4 Three types of cervical spondylolisthesis or spontaneous subluxation. A Displacement of atlas with the dens permitted by congenital or post-traumatic non-fusion of the dens with the axis. B Displacement of atlas on axis, from softening of the transverse ligament of the atlas. C Subluxation of a cervical vertebra upon the one next below it from instability of the intervertebral joint after previous injury. Instability may also be caused by rheumatoid arthritis.

Inflammatory softening of the transverse ligament of the atlas. In this type the underlying cause is an inflammatory lesion in the upper part of the neck, such as rheumatoid arthritis or a severe local infection of the throat or glands. There is rarefaction of the atlas, with softening of the transverse ligament. In consequence the atlas is able to slide forwards upon the axis (Fig. 12.4B).

Instability from previous injury or from arthritis. A traumatic fracture- dislocation or subluxation at any level in the cervical spine may cause permanent instability, with a liability to slow redisplacement months or years after the initial injury (Fig. 12.4C).

In all types the upper segment is displaced forwards in relation to the lower. The spinal canal becomes progressively more flexed and narrowed, and there is always a grave risk of compression of the spinal cord.

Clinical features. In the inflammatory type there is complaint of ‘stiff neck’. The head is held rigidly, the cervical muscles being in spasm. In subluxation from congenital or post-traumatic instability there are discomfort and stiffness in the neck, and flexion deformity is apparent. Radiographs will show the displacement, its level and its type (Fig. 12.5).

Fig. 12.5 Lateral radiograph of upper cervical spine in rheumatoid arthritis showing atlanto-axial subluxation. The anterior arch of the atlas has displaced anteriorly because of destruction by the rheumatoid inflammatory process of the transverse ligaments that normally hold it against the odontoid process of the axis. As a result the odontoid peg (arrow) will compress the anterior aspect of the spinal cord and medulla with severe neurological complications.

Complications. In all types the complication to be feared is compression of the spinal cord. The first symptoms appear in the upper limbs and consist of root pain, paraesthesiae, motor weakness, or sensory impairment. Eventually, increasing cord compression may lead to spastic paralysis below the level of the lesion, and to bladder and bowel dysfunction.

Treatment. This depends upon the underlying cause and upon whether or not neurological disturbance is present.

Inflammatory type. The displacement is reduced by head traction, which is continued for two weeks. Thereafter the neck is immobilised in extension in a plaster jacket for 2 months. Atlanto-axial fusion may be required.

Congenital or post-traumatic instability. If subluxation is not complicated by neurological disturbance, treatment may be expectant (observation only), by a plastic collar to give support, or by local fusion of the spine, according to the severity of the displacement and of the local symptoms. If neurological disturbance is present, treatment is by preliminary skull traction to reduce the displacement, followed by operative fusion of the affected segments of the spine.

TUBERCULOSIS OF THE CERVICAL SPINE (Tuberculous cervical spondylitis)

Tuberculosis is far less common in the cervical spine than in the thoracic and lumbar regions. It is now seldom seen in Britain, but it still occurs commonly in Africa and in Eastern countries. The general features of tuberculosis of bone were described in Chapter 7p. 92.

Pathology. The infection begins in the front of a vertebral body, or in an intervertebral disc (Fig. 12.6A). Destruction of bone and intervertebral disc leads to anterior collapse with consequent cervical kyphosis (Fig. 12.6B). The degree of destruction varies widely, depending upon the virulence of the organism and the resistance of the patient. Formation of pus leads either to a retropharyngeal abscess (behind the prevertebral fascia), which may eventually point at the posterior margin of the sternomastoid muscle, or, if the pus tracks posteriorly, to a suboccipital abscess. The spinal cord may be damaged by direct pressure of an abscess, or by secondary thrombosis of the vessels of the cord.

Fig. 12.6 Tuberculosis of the cervical spine. A The infection begins at the front margin of a vertebral body close to the intervertebral disc, or possibly in the disc itself, as indicated by the shaded area. B The opposing surfaces of the bodies of C4 and C5 have been eroded and the intervening disc is destroyed. Pus has collected behind the prevertebral fascia, forming a bulging retropharyngeal abscess.

Clinical features. The disease occurs mainly in children and young adults. There is pain in the neck and occiput, aggravated by movement. In addition, one or more of the following symptoms may be present: difficulty in swallowing; abscess or sinus at the side or back of the neck; neurological symptoms from spinal cord dysfunction, the upper limbs being affected before the lower. On examination the head is held rigidly, often supported by the hands. The cervical muscles stand out in spasm. One or more of the spinous processes may appear prominent, due to cervical kyphosis. There is local tenderness on firm palpation over the spinous processes. All movements of the head and neck are restricted, and cause pain if forced. An abscess may be present in the suboccipital region, behind the sternomastoid muscle, or behind the pharynx (see below). Associated tuberculous lesions elsewhere are common.

Imaging. Radiographs always show diminution of disc space, usually some destruction of bone (Fig. 12.6B), and sometimes an abscess shadow. MRI scans will provide more detailed information on the extent of the soft tissue abscess and assist in planning surgical drainage.

Investigations. The erythrocyte sedimentation rate is raised in the active stage. The Mantoux test is positive. Pus obtained by aspiration of an abscess may yield tubercle bacilli.

Complications. Retropharyngeal abscess. This causes difficulty in swallowing (dysphagia), and the posterior wall of the pharynx is seen to bulge forwards in the midline. Eventually the abscess may point behind the sternomastoid muscle. If neglected, it may rupture into the pharynx.

Spinal cord dysfunction. If the spinal cord is affected there will be neurological signs (sensory, motor, and visceral) at and below the level of the lesion, which may progress to complete paralysis.

Diagnosis. Important diagnostic features are the history of tuberculous contact or disease, spasm of the neck muscles with restriction of all movements, abscess formation, and the radiographic findings.

Treatment. The principles of treatment are the same as for other forms of skeletal tuberculosis. Antibacterial therapy: combinations of antituberculous drugs were described on page 102. Local treatment is by support for the cervical spine by a halo splint or by a plastic collar until the disease is quiescent – often a matter of several months.

Operation is sometimes required and the following are the main indications:

PYOGENIC INFECTION OF THE CERVICAL SPINE (Pyogenic cervical spondylitis)

Infection of the cervical vertebrae or intervertebral discs with pyogenic organisms is uncommon. It is usually caused by the staphylococcus, streptococcus, or pneumococcus, and occasionally by other bacteria, including salmonella organisms or Brucella abortus.

Pathology. The organisms reach the spinal column by the general blood stream (from a septic focus elsewhere), by lymphatic channels (from a local infection, for instance in the pharynx), or possibly by the spinal venous plexus (from a focus in the pelvis). As in tuberculous spondylitis, there is destruction of bone and intervertebral disc, with or without abscess formation. The spinal cord may be damaged by direct pressure or by thrombosis.

Clinical features. The onset is usually acute or subacute, with pyrexia. The clinical features resemble those of tuberculous spondylitis (p. 192), but the course is more rapid. A suppurative process elsewhere in the body (for instance, in the pharynx or pelvis) is usually present. Radiographs show local osteoporosis or erosion of bone, diminution of disc space, and sometimes subligamentous new bone formation.

Investigations. The erythrocyte sedimentation rate and C-reactive protein level is raised and polymorphonuclear leucocytosis is to be expected.

Diagnosis. The condition must be distinguished from tuberculous spondylitis; the relatively rapid onset and course, with pyrexia and leucocytosis, and identification of the causal organism in pus, are the main diagnostic criteria.

Treatment. Appropriate antibiotic drugs (see p. 89) should be given systemically. The cervical spine must be immobilised in a rigid collar or brace; sometimes sustained head traction with a halo splint is required for relief of spasm. When there is an abscess it should be drained, especially if the spinal cord is threatened. Spontaneous fusion of the affected vertebrae usually makes operative fusion unnecessary.

RHEUMATOID ARTHRITIS (General description of rheumatoid arthritis, p. 134)

The cervical spine is the third most commonly affected in rheumatoid polyarthritis, after the hands and feet. In sero-positive disease up to 50% will show evidence of destructive synovitis in the vertebral joints. It is important that this be recognised, because there is a risk that destruction of the intervertebral joints may allow gradual forward subluxation of a cervical vertebra upon the one next below it, with danger to the integrity of the spinal cord. There is a particular risk of subluxation at the atlanto-axial joint due to softening of the transverse ligament of the atlas (see Fig. 12.5). Destructive changes may also occur at multiple levels below the axis vertebra and may result in subluxation causing progressive spinal cord or nerve root compression. It is important to remember that these destructive changes may occur insidiously without significant symptoms because of the involvement of the upper and lower limb joints; thus they may be overlooked until the onset of paralysis.

Warning symptoms that should alert the clinician to impending cord damage are sensory paraesthesia and sensations of ‘electric shocks’ in the hands with increased muscle tone and spasticity in the legs. Dizziness, tinnitus and vertigo may also occur and are indicative of vertebral artery insufficiency.

Treatment. If the patient experiences significant neck pain and erosion of the intervertebral joints or subluxation at any level are demonstrated radiologically, the neck should be splinted with a moulded soft plastic collar. In a few patients when neurological impairment becomes progressive MRI scanning is required to evaluate the extent of spinal cord compression. If this is present more active surgical treatment is indicated; initially with skull traction or a halo brace to correct the subluxation, followed by posterior spinal fusion or occipito-cervical fusion.

ANKYLOSING SPONDYLITIS

Ankylosing spondylitis is a disease that creeps up the spine from below having originated in the sacro-iliac joints and the lumbar spine. In a high proportion of cases – though by no means in all – it extends to involve the cervical region, with aching pain and permanent stiffness – sometimes total rigid ankylosis – of the intervertebral joints. Very occasionally the neck may become ankylosed in an extreme degree of flexion producing a ‘chin on chest’ deformity. When this interferes with swallowing and the ability to see ahead it may justify surgical correction by osteotomy and fusion. This is very high-risk surgery with a 20% mortality rate and should only be undertaken in specialised centres by surgeons with the necessary skills. The disease of ankylosing spondylitis as a whole will be described in Chapter 13 (p. 229).

CERVICAL SPONDYLOSIS (Cervical spondylarthritis; cervical spondylarthrosis; cervical osteoarthritis; cervical osteoarthrosis)

Degenerative changes are common in the cervical spine. Indeed, they are found almost universally in some degree in persons over 50 years of age. Beginning in the intervertebral discs, they affect the posterior intervertebral (facet) joints secondarily, causing pain and stiffness of the neck, sometimes with referred symptoms in an upper limb.

Cause. The primary degenerative changes may be initiated by injury, but usually the condition is simply a manifestation of normal ageing processes.

Pathology. Degenerative arthritis occurs most commonly in the lowest three cervical joints. The changes affect first the central intervertebral joints (between the vertebral bodies) and later the posterior intervertebral (facet) joints. In the central joints there is degenerative narrowing of the intervertebral disc, and bone reaction at the joint margins leads to the formation of osteophytes (Fig. 12.7A). In the posterior intervertebral joints the changes are those of osteoarthritis in any diarthrodial joint – namely, wearing away of the articular cartilage and the formation of osteophytes (spurs) at the joint margins (Fig. 12.7B).

Fig. 12.7 Osteoarthritis of the cervical spine. At first there is simply degeneration and narrowing of the intervertebral disc, with the formation of osteophytes anteriorly A. Later, the posterior or facet joints are affected: the articular cartilage is worn away and marginal osteophytes may encroach upon the intervertebral foramen B.

Secondary effects. Osteophytes commonly encroach upon the intervertebral foramina, reducing the space for transmission of the cervical nerves (Fig. 12.7B). If the restricted space in a foramen is reduced still further by traumatic oedema of the contained soft tissues, manifestations of nerve pressure are likely to occur. Exceptionally, the spinal cord itself may suffer damage from encroachment of osteophytes within the spinal canal.

Clinical features. The symptoms are in the neck or in the upper limb, or both.

Neck symptoms consist chiefly of aching pain in the back of the neck or in the trapezius area, a feeling of stiffness, and ‘grating’ on movement. Usually slight, they are liable to periodic exacerbations, probably from unremembered strains or repetitive movements: exacerbations may be interspersed with periods of freedom from pain. Occipital headache may be a feature if the upper half of the cervical spine is affected.

In the upper limb there may be a vague, ill-defined and ill-localised ‘referred’ pain spreading over the shoulder region, or there may be more serious symptoms from interference with one or more of the cervical nerves in their foramina. The main feature of nerve root irritation is radiating pain along the course of the affected nerve or nerves, often reaching the digits. There may also be paraesthesiae in the hand, in the form of tingling or ‘pins and needles’. Noticeable muscle weakness is uncommon.

On examination, the neck may be slightly kyphotic. The posterior cervical muscles may be somewhat tender but they are not in spasm. Movements are not markedly diminished except during acute exacerbations or when the degenerative changes are very advanced. Audible crepitation on movement is common. In the upper limb objective findings are usually slight or absent, for nerve pressure is seldom great enough to produce well-defined objective neurological signs (compare prolapsed intervertebral disc). Thus demonstrable motor weakness or sensory impairment is exceptional. Depression of one or more of the tendon reflexes is, however, fairly common.

Radiographic features. There is narrowing of the intervertebral disc space, with formation of osteophytes at the vertebral margins, especially anteriorly (Fig. 12.8A). A single vertebral level may be affected – often at the C5–C6 or C6–C7 level – or there may be changes at more than one level. Encroachment of osteophytes upon an intervertebral foramen is demonstrated best in oblique projections (Fig. 12.8B) or on CT scans. In a few patients with clinical evidence of neurological impairment MRI scanning may be indicated to identify nerve root or cord compression.

Fig. 12.8 Cervical spondylosis. Note in the lateral view A the narrowed intervertebral space, with marginal osteophyte formation, at C5–C6 and at C6–C7. The oblique view B shows severe encroachment of osteophytes upon an intervertebral foramen (compare with the normal foramen below).

Diagnosis. Distinction has to be made from:

Fig. 12.9 Seven causes of interference with the brachial plexus or its roots. 1. Tumour of cord. 2. Tumour of spinal column. 3. Tumour of nerve root. 4. Prolapsed cervical disc. 5. Cervical spondylosis (osteoarthritis). 6. Cervical rib. 7. Tumour at thoracic inlet.

Treatment. There is a strong tendency for the symptoms of cervical spondylosis to subside spontaneously, though they may persist for many weeks and the structural changes are clearly permanent. Treatment is thus aimed towards assisting natural resolution of temporarily inflamed or oedematous soft tissues. In mild cases such measures include anti-inflammatory analgesic drugs and muscle relaxants as well as various forms of physiotherapy. Ultrasound, short-wave diathermy, massage, and intermittent traction have all been used, but none have been shown to be effective in large clinical trials. Some benefit has been shown for mobilisation and strengthening exercises. Manipulation is sometimes recommended, but in the presence of extensive osteophytes it is hazardous because it may damage the spinal cord; it should therefore be employed with extreme caution, and only by those familiar with a gentle technique. In the more severe cases it is wise to provide rest and support for the neck by a closely fitting protective cervical collar (Fig. 12.10A), but this should only be worn for a few weeks until the acute symptoms subside to prevent atrophy of the spinal muscles.

Fig. 12.10 Cervical collars used in the treatment of painful neck disorders. The simple polythene support A gives only symptomatic relief and minimal support. The more rigid adjustable orthosis B and C can be fitted to limit flexion and extension of the spine and provides some stability in more severe disease.

In the exceptional cases in which radiculopathy or myelopathy is progressive and bony impingement can be demonstrated by imaging, surgical decompression may be required. For nerve root compression this can be achieved by a foraminotomy procedure, but where cord compression is present the type of operation is dictated by the site of bone impingement. In the commoner anterior compression from osteophytes on the vertebral body, an anterior discectomy combined with an interbody fusion gives best results. When compression is posterior from thickening of the laminae, a posterior laminectomy is required with a lateral facet joint wiring and fusion.

PROLAPSED CERVICAL DISC

Displacement of intervertebral disc material in the cervical spine is much less common than it is in the lumbar region. It is characterised by pain and stiffness in the neck, often with neurological manifestations in the upper limb and occasionally with signs of spinal cord compression.

Cause. Sudden jarring injury may be a predisposing factor, though a history of injury cannot be obtained in every case. Probably an intrinsic degenerative change in the substance of the disc makes it prone to rupture and displacement.

Pathology. The disc between C5–C6 and that between C6–C7 are those most frequently affected. Part of the gelatinous nucleus pulposus protrudes through a rent in the annulus fibrosus at its weakest part, which is postero-lateral; or part of the annulus itself may be displaced. If slight, the protrusion bulges against the pain-sensitive posterior longitudinal ligament, causing local pain in the neck. If large, the protrusion herniates through the ligament and may impinge upon the nerve leaving the spinal canal at that level (postero- lateral prolapse) (Fig. 12.11A), or occasionally upon the spinal cord itself (central prolapse) (Fig. 12.11B). Healing is probably by shrinkage and fibrosis of the extruded material rather than by its reposition within the disc. Secondary effects: Prolapse of a disc accelerates its degeneration and predisposes to the development of osteoarthritis (cervical spondylosis) in later years.

Fig. 12.11 Prolapsed cervical disc. A shows a postero-lateral prolapse, with compression of the issuing nerve. B shows the much less common central prolapse, with impingement upon the spinal cord.

Clinical features. Central protrusions. These lead to manifestations of spinal cord compression and may be confused with spinal cord tumours or other central neurological disorders. They fall within the province of the neurosurgeon rather than the orthopaedic surgeon.

Postero-lateral protrusions. A typical clinical picture is as follows. The patient sustains an injury to the neck – often a jarring or twisting strain – which may seem slight at the time and may cause no immediate effects. Hours or days later there is a rapid development of acute ‘stiff neck’ with severe pain made worse by coughing or similar strains. Later still, the pain begins to radiate over the shoulder and throughout the length of the upper limb; it is felt strictly in the course of a cervical nerve, and characteristically it is severe. Paraesthesiae are felt in the digits. On examination, there is limitation of certain neck movements by pain, but movement in at least one direction (often lateral flexion) is free. In the upper limb there is a full range of joint movements. There are slight muscle wasting and slight sensory impairment in the distribution of a cervical nerve. The corresponding tendon reflex (biceps jerk in C5–C6 lesions; triceps jerk in C6–C7 lesions) is depressed or absent.

Variations. The characteristic features described are not always present. Variations are common. Thus a history of injury is not always obtainable. The symptoms may be confined to the neck, the upper limb being spared; or they may be confined entirely to the upper limb. Motor changes (wasting and weakness) may be marked, sometimes amounting to almost complete paralysis of a muscle or a group of muscles; or on the other hand they may be absent. Similarly, wide variations in the degree of sensory impairment are noted.

Imaging. Radiographs characteristically show a normal appearance in the first attack, but narrowing of one of the disc spaces (usually C5–C6 or C6–C7), denoting long-standing disc degeneration, is often demonstrable. Magnetic resonance imaging may show the displaced disc material and its relationship to the nerve roots and cord (Fig. 12.12).

Fig 12.12 A and B Sagittal and axial MR scans showing a posterior cervical disc protrusion at the C6–C7 level. On the axial scan B the disc material is seen lying on the left side of the canal extending into the exit foramen (arrow) and compressing the underlying C6 nerve root.

Diagnosis. Prolapsed cervical disc has to be differentiated:

The main conditions that may be confused with it are the same as those listed in the differential diagnosis of cervical spondylosis (p. 196). A confident diagnosis is justified only when a suggestive history is associated with the signs of a lesion of a single cervical nerve, and provided always that other possible causes have been excluded by careful investigation.

Relationship between prolapsed disc and cervical spondylosis

The clinical features of the two conditions are similar. Distinction is difficult if the radiographs show arthritic changes, because the arthritis may be only incidental and itself symptomless. Nerve pressure is probably greater in prolapsed disc than in osteoarthritis: consequently the symptoms tend to be more clearly defined and pain very severe; and the objective signs are more marked.

Course. There is a strong tendency to spontaneous recovery, but symptoms often persist with decreasing severity for as long as six months or more.

Treatment. This depends upon the nature and severity of the individual case. When the symptoms are slight no treatment other than perhaps a mild analgesic drug is required. In the more severe cases treatment is advisable, especially in the early acute stage. If the neck is ‘stiff’ and if movements aggravate the neck and limb pain, rest for a few weeks in a supportive collar made from heat-moulded reinforced plastic or a more rigid adjustable orthosis (Fig. 12.10) is the most satisfactory method. Pain is usually severe, necessitating fairly intensive analgesic therapy. As the acute symptoms gradually subside, physiotherapy in the form of graduated neck exercises to restore full mobility and muscle strength is often helpful.

In cases of intractable radicular pain or myelopathy surgical treatment may be required. Removal of the affected degenerative disc material can be achieved through an antero-lateral approach to the vertebral bodies (Fig. 12.13). This displaces the sterno-mastoid muscle and contents of the carotid sheath laterally, with the strap muscles, trachea and oesophagus moved medially to expose the pre-vertebral fascia. It is important to confirm the correct intervertebral space with intra-operative radiography before disc removal. Distraction of the vertebral bodies facilitates removal of the disc and the space created is then filled with a block of autogenous cortico-cancellous bone graft to produce an anterior interbody fusion. The technique can also be applied to disc degeneration at more than one level by the use of a longer strut graft (see Fig. 4.4A), usually reinforced with a plate and screws. Postoperatively the neck is immobilised in a light collar until there is radiological evidence of bone healing.

Fig 12.13 Surgical approach to the anterior aspect of the cervical spine. In the mid-cervical spine, dissection between the trachea and oesophagus medially and the carotid sheath laterally is relatively avascular compared with the posterior approach through thick muscle layers.

Because of the loss of movement that follows intervertebral fusion, attempts are now being made to replace the degenerate disc with an artificial prosthetic replacement, but as yet the procedure is experimental and no long-term results are available.

CERVICAL RIB

A cervical rib is a congenital over-development, bony or fibrous, of the costal process of the seventh cervical vertebra. It often exists without causing symptoms, especially in the young, but in adult life the tendency to gradual dropping of the shoulder girdle may lead to its causing neurological or vascular disturbance in the upper limb.

Pathology. The over-developed costal process may be unilateral or bilateral. It may be of any size from a small bony protrusion, often with a fibrous extension, to a complete supernumerary rib. The subclavian artery and the lowest trunk of the brachial plexus arch over the rib. In a proportion of cases the nerve trunk suffers damage at the site of pressure against the rib; this accounts for the neurological manifestations. The vascular changes are probably similarly accounted for by local damage to the subclavian artery, from which thrombotic emboli may be repeatedly discharged into the peripheral vessels of the upper limb.

Clinical features. Cervical rib is often symptomless. When symptoms occur, they usually begin during early adult life. They may be neurological, vascular, or combined.

Neurological manifestations. The sensory symptoms are pain and paraesthesiae in the forearm and hand, most marked towards the medial (ulnar) side, and often relieved temporarily by changing the position of the arm. The motor symptoms include increasing weakness of the hand, with difficulty in carrying out the finer movements.

On examination, there is usually an area of sensory impairment – sometimes complete anaesthesia – in the forearm or hand. The affected area does not correspond in distribution to any of the peripheral nerves, but may be related to the lowest trunk of the brachial plexus. There may be wasting of the muscles of the thenar eminence or of the interosseous and hypothenar muscles.

Vascular manifestations. The changes that have been observed range from dusky cyanosis of the forearm and hand to gangrene of the fingers. The radial pulse may be weak or absent.

Radiographic features. Radiographs show the abnormal rib: if small, it is seen best in oblique projections (Fig. 12.14). In cases of suspected vascular obstruction arteriography is required.

Fig. 12.14 Cervical rib. Typical appearance of a small supernumerary rib. This one caused severe neurological symptoms and signs. A cervical rib is shown best in an oblique radiograph such as this.

Diagnosis. Radiographic demonstration of a cervical rib does not prove that it is the cause of symptoms. The condition has to be distinguished:

The diagnosis of symptomatic cervical rib depends upon the detection of the characteristic neurological signs or vascular disturbance in association with a demonstrable supernumerary rib. Prolapsed intervertebral disc at C7–T1 gives a similar clinical picture neurologically, and indeed it may often be the true cause of symptoms ascribed to a cervical rib; but in prolapsed disc there is a strong tendency to natural recovery, which is not the case with cervical rib. Arteriography may be conclusive by revealing obstruction of the subclavian artery.

Treatment. This depends upon the severity of the subjective and objective manifestations. In mild cases physiotherapy in the form of ‘shrugging’ exercises, to improve the tone of the elevator muscles of the shoulder girdle, is adequate. But if the neurological or vascular signs are well marked, and especially if they are increasing, operation is advisable. First the scalenus anterior muscle is divided. If this does not demonstrably release the lowest nerve trunk from constricting pressure the scalenus medius should be divided and the abnormal rib removed.

Occlusion of the subclavian artery may be amenable to reconstruction by vein grafting if the diagnosis is made before irreversible changes in the limb have occurred.

SCALENUS SYNDROME (First rib syndrome; thoracic outlet syndrome)

Occasionally the neurological manifestations characteristic of cervical rib occur in the absence of a demonstrable skeletal abnormality. They have been ascribed to trapping of nerves between the first rib and the clavicle (costo-clavicular compression), or between the first rib and the scalenus anterior muscle; and to stretching of the lowest trunk of the brachial plexus over the normal first rib. More often, they are caused by a tough fibrous band in the scalenus medius muscle, which may lead to kinking of the lowest trunk of the brachial plexus, demonstrable at operation. The symptoms are easily confused with those from a prolapsed intervertebral disc between C7 and T1. Treatment should be conservative at first, as for prolapsed disc. Gradual improvement would support the diagnosis of disc prolapse. But if the symptoms persist with undiminished intensity for a long time a true scalenus syndrome is probably the cause. In that event it may be justifiable to explore the plexus, to divide the scalenus anterior and the scalenus medius, and if necessary to excise the first rib.

SOFT-TISSUE STRAIN OF THE NECK (‘Whiplash’ injury)

Soft-tissue strain of the neck – commonly termed whiplash injury – is a common cause of persistent pain and stiffness in the neck. It occurs frequently in occupants of cars struck violently from behind by other vehicles (‘rear-end shunts’). Similar strains may also occur in head-on collisions.

Mechanism of injury and pathology. At the moment of impact the head is first thrown backwards as the vehicle in which the victim is seated is suddenly jolted forwards, often without any warning. This is followed by rebound flexion of the neck, often so extreme that the chin abuts against the manubrium of the sternum, and by a second extension movement. It is assumed that there is strain of the deep muscles and ligaments of the cervical spine. In the great majority of cases in which the patient attends at a hospital, radiographs do not show any structural damage in the spinal column.

Clinical features. At impact the patient usually feels jolting or ‘wrenching’ of the neck or of one or other shoulder; but often there is no severe pain initially and the patient may think at first that he has escaped significant injury. However, within hours of the accident – occasionally as late as a day or more afterwards – there is increasing pain and ‘stiffness’ in the back of the neck, often with extension of the pain to the top and back of one or other shoulder. The neck pain is usually accompanied by severe headache, which may be persistent. Examination shows restriction of the range of movement of the cervical spine, usually in all directions at first, but later more localised.

Symptoms from whiplash injury of the neck are often very slow to subside, and whereas some patients show full recovery in a matter of weeks, it is common for patients to complain of lingering neck and shoulder pain, with or without recurrent headaches, for as long as one or two years, and sometimes even longer. In long protracted cases it is often found that the patient has become demoralised, and consequent psychological upset may delay recovery.

Treatment. Whiplash strain does not respond well or regularly to any particular form of treatment: as is so often the case with soft-tissue strains, time is the best healer. In general, the principles of treatment should be to provide support and rest for the neck in the initial stages, in the form of a protective cervical collar. But after a week or so the emphasis should be rather on the restoration of mobility by regular exercises within the limits imposed by pain, preferably under the supervision of a physiotherapist.

TUMOURS IN RELATION TO THE CERVICAL SPINE AND EMERGING NERVES

Tumours involving the cervical spine or the related nerves may arise:

Tumours of the spinal column are more often malignant than benign, and predominantly metastatic rather than primary tumours. A meningeal tumour (meningioma) is an uncommon cause of compression of the spinal cord. A tumour arising in nerve (neurofibroma) occurs occasionally within an intervertebral foramen, where it may grow inwards to compress the spinal cord and outwards towards the surface (‘dumb-bell’ tumour). A tumour at the apex of the lung (Pancoast’s tumour) is a well-recognised cause of severe pain from invasion of the brachial plexus.

Clinical features. The effects of these tumours vary according to their site and nature. Broadly, there may be:

Destruction and collapse of cervical vertebrae. The commonest cause is a metastatic carcinoma (Fig. 12.15). The clinical features are local pain and, usually, flexion deformity. The spinal cord or the issuing cervical nerves may be involved, with corresponding signs of spinal cord compression or peripheral nerve defect.

Fig. 12.15 Partial destruction of the body of the third cervical vertebra by a metastasis from a renal carcinoma.

Spinal cord compression. Interference with the function of the spinal cord may be caused by tumours of the cord itself or of its meninges, by tumours of nerves (neurofibroma), or by tumours of the bony spinal column. The clinical manifestations depend upon the location of the tumour. Typically, root pain at the level of the lesion is followed by lower motor neurone changes at the same level and by progressive upper motor neurone paralysis and visceral dysfunction below the lesion.

Interference with the brachial plexus. Nerves forming the brachial plexus may be involved by tumours of the nerves themselves (neurofibroma), by bone tumours, or by tumours at the thoracic inlet (Fig. 12.16). The predominant features are severe pain along the course of the nerve or nerves affected (neck or upper limb) and increasing motor and sensory impairment in the distribution of the nerves.

Fig. 12.16 Tumour at the thoracic inlet (apical lung carcinoma or Pancoast’s tumour) causing well-marked opacity at the apex of the right lung. This tumour should always be borne in mind in the differential diagnosis of pain in the upper limb.

Imaging. Plain radiographs will usually help in discovering a tumour arising in the bones of the spinal column or eroding the bones from outside (Fig. 12.15). They may also reveal a tumour at the thoracic inlet (Fig. 12.16). Computerised tomography or magnetic resonance imaging may give more precise information. Radiographs of the chest may reveal an apical lung tumour or pulmonary metastases.