INTRODUCTION

Neck discomfort commonly appears after sudden and unusual motion of the neck because the cervical spine is the most mobile segment of the spine. Many delicate and vital structures pass through the cervical spinal column, including the carotid and vertebral arteries, the spinal cord, and the spinal nerves, all of which require great protection.

Normal function of the cervical spine requires that all movements be accomplished without injury to the spinal cord and the millions of nerve fibers that pass through it. The spinal cord has the capacity to adapt itself to marked alteration in the length of the cervical spinal canal. Flexion of the neck lengthens the spinal canal, and extension shortens it. The thickness of the cervical spinal cord and the diameter of the spinal canal vary considerably from person to person.

The nerve roots in the neck are particularly vulnerable to injury because of their relatively horizontal position in comparison with those of the lumbar spine. Stretching of the spinal cord itself is greatest at the cervical spine, which also predisposes the cord and nerve roots to trauma (Tables 3-1 and 3-2).

TABLE 3-2 CERVICAL SPINE CROSS-REFERENCE TABLE BY SYNDROME OR TISSUE

Arthritis

Jackson cervical compression test Rust sign Soto-Hall sign Swallowing test

Brachial plexus Dural irritation Facet Fracture Intervertebral disc syndrome Meningitis Myospasm Nerve root Sprain Subluxation Tumor Vertebrobasilar artery syndrome

Many provocative tests can be used for the cervical spine. The anatomic structures commonly tested are dural tension, foraminal and vertebral canal patency, and muscle, tendon, or ligamentous injuries (Table 3-3). During investigation of the upper extremity, the examiner must differentiate between canal or nerve root lesions by physical examination and, if necessary, electrodiagnostic studies. Cervical spine canal stenosis, whether of bony or soft-tissue origins, can cause lower-extremity signs and symptoms. Most notable is long tract pain, or rhizalgia, appearing in an ipsilateral leg with a cervical nerve root lesion (Table 3-4).

TABLE 3-3 COMMON PROVOCATIVE TESTS TO EVALUATE THE SPINE

Provocative Test	Anatomic Structures Being Tested	Positive Finding(s)
Cervical Spine
Jackson compression test	Dural sheath, nerve root, spinal nerve	Radicular pain
Spurling compression test	Dural sheath, nerve root, spinal nerve	Radicular pain
Maximal foraminal compression test	Dural sheath, nerve root, spinal nerve	Radicular pain
Distraction test	Dural sheath, nerve root, spinal nerve	Relief of radicular pain
Shoulder depression test	Dural sheath, nerve root, spinal nerve, brachial plexus	Radicular pain to one or more dermatomes
E.A.S.T. test	Subclavian artery	Vascular compromise
Eden test	Scalene musculature	Radiculopathy to multiple dermatomes or vascular compromise
Thoracic Spine
Wright hyperabduction test	Pectoralis minor	Vascular compromise, subclavian artery, TOS
Tests for anterior thoracic wall	Peripheral nerve, muscles	Radicular pain, dull ache
Lumbar Spine
Straight leg raise	Dural sheath, nerve root, spinal nerve	Radiculopathy to one dermatome usually
Braggard test	Dural sheath, nerve root, spinal nerve	Radiculopathy to one dermatome usually
Bekhterev (Bechterew) test	Dural sheath, nerve root, spinal nerve	Radiculopathy to one dermatome usually
Neri bow string test	Dural sheath, nerve root, spinal nerve	Radiculopathy to one dermatome usually

E.A.S.T., Elevated arm stress test; TOS, thoracic outlet syndrome.

From Greenstein GM: Clinical assessment of neuromusculoskeletal disorders, St Louis, 1997, Mosby.

TABLE 3-4 CLASSIFICATION OF POST–SPINAL CORD INJURY PAIN STATES

Acute Phase Pains	Chronic Phase Pains
Acute nociceptive (spinal injury site) Early neurogenic Early burning Transitional zone pain	Nociceptive (musculoskeletal, spasm) Neurogenic Peripheral Transitional zone pain Double lesion syndrome pain Visceral pain (?) Central Central dysesthesia syndrome pain Syringomyelia pain Visceral pain (?) Psychogenic

Adapted from Beric A: Post-Spinal Cord Injury Pain States, Anesthesiol Clin North Am 15(2):445-463, 1997.

ESSENTIAL CLINICAL ANATOMY

The atlas consists of a pair of strong lateral masses that are linked by the anterior arch and the posterior arch. The posterior arch of the atlas is attached to the posterior rim of the foramen magnum by the atlantooccipital membrane.

Children often have lax ligaments, which increases spinal motion. This characteristic most commonly occurs in the cervical region. Increased motion seen during physical or X-ray examination should be differentiated from pathologic subluxation. On imaging of the cervical spine, the predental space should not exceed 3 mm. A predental space greater than 3 mm has been found in 20% of normal patients younger than 8 years and can be tracked on patients into early adulthood.

Pathologic subluxation of the atlas on the axis that compromises the spinal cord (compressive myelopathy) is associated with rheumatoid arthritis and ankylosing spondylitis. The common characteristic of these disorders is the destructive weakening of the atlantooccipital ligament system, with resultant translation of the structures.

The costal element in C7 is one of the most common from which accessory ribs may form (e.g., a cervical rib). Abnormal positioning of a cervical rib heightens the risk of compression of the nerves and vessels.

The articulations of the vertebral column are of great importance. The vertebral column supports much weight; serves as an axis for movement of the limbs, trunk, head, and neck; and protects the spinal cord from trauma.

The intervertebral discs are fibrocartilaginous flattened structures interposed between adjacent vertebral bodies. Each disc consists of a gelatinous inner region (i.e., the nucleus pulposus), surrounded by a solid ring of stiffer material (i.e., the annulus fibrosus).

The vertebral artery is closely related to the cervical spine and is the first branch of the subclavian artery. It enters the foramen of the transverse process of C6 and ascends through the remaining foramina of the tops of the cervical vertebrae. The vertebral artery passes beneath the posterior atlantooccipital membrane. The union of the two vertebral arteries forms the basilar artery.

ESSENTIAL MOTION ASSESSMENT

During a cervical spine range-of-motion assessment, the examiner should examine active then passive movements. For flexion, the patient brings the chin onto the chest; for extension, the patient bends the head backward as far as possible. For lateral flexion, the patient brings an ear toward the shoulder, first on one side and then on the other. For rotation, the patient looks over one shoulder and then the other. Repeating the movements while applying gentle pressure over the vertex of the skull may trigger pain or paresthesia in the arm if a critical degree of narrowing exists at an intervertebral foramen. In evaluating cervical spine range of motion, the examiner observes not only the total range of movement, but also the smoothness and comfort with which the patient accomplishes the motions (Figs. 3-1 to 3-8).

ESSENTIAL MUSCLE FUNCTION ASSESSMENT

The muscles of the vertebral column are often in an increased state of contraction, which stiffens the vertebral column to serve as a platform for movement of the head or limbs.

The intrinsic longitudinal vertebral muscles, placed more superficially, are collectively called the erector spinae. The cervical region contains elongated muscles originating from the spinous process (the splenius muscles) and others from the transverse processes (the semispinalis muscles). The suboccipital muscles are a special group of muscles linking the atlas, the axis, and the base of the skull.

ESSENTIAL IMAGING

BAKODY SIGN

PROCEDURE

BARRÉ-LIÉOU SIGN

PROCEDURE

BIKELE SIGN

PROCEDURE

BRACHIAL PLEXUS TENSION TEST

PROCEDURE