Cervical osteochondrosis

Mechanism of development (pathogenesis)

The basis for the development of cervical radicular syndromes is intervertebral foraminal stenosis of a degenerative nature. Cervical vertebrae possess an important anatomical feature: their endplates are elevated laterally. These structures are called uncinate processes, and it is they that give the vertebral body its specific saddle-like shape.

The pathogenesis of compression develops in several stages:

1. Degeneration of the intervertebral disc begins, leading to a decrease in its height.
2. The body of the superior vertebra gradually sinks into the saddle-shaped depression of the inferior one.
3. Due to this, pressure on the uncinate processes increases manifold, triggering the process of their bone remodeling.
4. The processes deviate laterally and posteriorly, causing progressive narrowing (stenosis) of the intervertebral foramina.

Most commonly, the pathology affects the $C_V–C_{VI}$ and $C_{VI}–C_{VII}$ levels, somewhat less frequently the $C_III–C_{IV}$ and $C_{VII}–Th_I$ levels. Stenosis can form unilaterally or bilaterally, affecting one or several segments simultaneously. Furthermore, disc degeneration is frequently combined with arthrosis of the zygapophyseal (facet) joints, which further restricts neck mobility.

Clinical manifestations and radicular syndromes

The very first clinical manifestation of cervical osteochondrosis is cervical dysalgesia. Patients report intense and constant neck pain that manifests after sleep and sharply intensifies when attempting to turn the head (movements are sometimes accompanied by a crunching sound). On objective examination, the physician reveals a forced position of the cervical spine, sharp restriction of mobility, pronounced muscle tension, and tenderness upon palpation of paraspinal points and percussion of spinous processes.

When nerve roots are involved in the process, the symptoms depend on the severity of the lesion:

• Irritation stage: pain and paresthesias predominate in the innervation zone of the affected segments.
• Compression stage: sensory disturbances (hypoalgesia), motor disorders (paresis), and loss of reflexes join in.

The clinical picture is strictly tied to the level of the lesion:

• C3 and C4 roots: cause pain in the neck and shoulder girdle. In rare cases, partial diaphragmatic paresis is possible.
• C5 root: pain and hypoalgesia in the corresponding dermatome, motor weakness of the deltoid (m. deltoideus) and biceps brachii (m. biceps brachii) muscles.
• C6 root: pain syndrome in the C6 dermatome, weakness of the biceps brachii and brachioradialis (m. brachioradialis) muscles. Diminished biceps reflex is characteristic.
• C7 root: pain and paresthesias in the C7 dermatome, weakness of the triceps brachii (m. triceps brachii) and pronator teres (m. pronator teres) muscles. The triceps reflex is diminished, and trophic disorders—atrophy of the thenar eminence muscles—are possible.

Instrumental diagnostics

Comprehensive instrumental diagnostics is necessary for an accurate diagnosis and selection of patient management tactics. It is important to remember the clinical rule: in osteochondrosis, there is no constant parallelism between the severity of symptoms and the radiological picture.

• Radiography: standard spondylograms show decreased disc height, sclerosis of the endplates, presence of osteophytes, and static changes. Functional radiography (images in maximum flexion and extension) is critically important for identifying segmental instability and subluxations in the intervertebral joints.
• CT and MRI: indicated for the first signs of root compression, as well as when planning surgery. CT excellently visualizes bone structures and disc dimensions, while MRI allows for a detailed assessment of spinal cord anatomy, exact herniation localization, and the degree of compression of the dural sac and vessels.
• Electrophysiological tests: electromyography (EMG) and somatosensory evoked potentials (SSEPs) are used for topographic diagnosis of the nature and level of nerve structure lesions.

Principles of conservative treatment

The main goal of conservative orthopedic treatment during an acute period is spinal decompression. This helps reduce reflex muscle spasm and intradiscal pressure, which ultimately reduces nerve root irritation and reactive edema.

• Orthopedic regimen and traction: the patient is shown a supine position on a hard board with a small pillow under the head and a bolster (or a bag of warm sand) under the neck. Glisson's loop (in a vertical or horizontal position) is actively used for cervical traction.
• Medication support: analgesics and NSAIDs (rheopyrine, ibuprofen, voltaren, movalis), muscle relaxants (sirdalud), decongestants (furosemide), and sedatives (nozepam) are used.
• Therapeutic blockades: for rapid pain relief in cervical osteochondrosis, Popelyansky's novocaine blockade of the anterior scalene muscle is used. Technique: the neck is tilted toward the affected side, the head is turned to the healthy side, the sternocleidomastoid muscle is displaced medially, and an injection is made along the lower edge of the scalene muscle to a depth of 0.5–0.7 cm (2 ml of a 2% novocaine solution is administered).
• Physiotherapy and manual therapy: UV therapy in erythematous doses, novocaine electrophoresis, ultrasound, and diadynamic currents are prescribed. Electroanalgesia (Delta-101, Miorhythm devices) and reflexology methods are effective. Manual therapy is aimed at working with vertebral-motor segments to eliminate neurological manifestations.

Class and exam questions

What else to study on this topic

• Anterior scalene muscle syndrome: anatomical boundaries and clinical features.
• Comparative characteristics of cervical and lumbar osteochondrosis.
• Electrophysiological tests (EMG, SSEP) in topical diagnosis.
• Biomechanics of root compression in posterolateral and foraminal herniations.
• Technique of epidural and paraspinal blockades.

Other topics in the section "DeMyer's The Neurologic Examination" / "Duus' Topical Diagnosis in Neurology"

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