Examination of the Cervical Spine

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CHAPTER 48 Examination of the Cervical Spine

Hillel M. Sommer, Brinda S. Kantha, Larry H. Chou

SCOPE AND LIMITATIONS

Perhaps there is no better example of the ‘art’ of medicine than in a review of the various physical examination techniques used in clinical diagnosis. More than any other organ system, the musculoskeletal system is the purview of a diverse group of medical specialists and subspecialists who care for persons with spinal and spine-related pain.

In the field of medicine alone, the responsibility for physical diagnosis is undertaken by many disciplines including neurology, neurosurgery, occupational medicine, orthopedic surgery, physical medicine and rehabilitation, sports medicine, etc. Beyond allopathic medicine there are osteopathic physicians, chiropractors, and physical therapists among others who examine the spine. While there are some elements common to all groups, each craft presents its own unique nomenclature and terms of reference and stakes a claim to the role of gatekeeper for musculoskeletal pathology.

This diversity leads to a heterogeneous approach to the physical diagnosis of spinal pain. Examination techniques vary widely both across and within disciplines. The algorithm used to make a diagnosis by examination is derived primarily from a particular practitioner’s own experience and education and promulgated via authoritative opinion. These techniques are passed down from generation to generation as one clinician incorporates it as part of his own routine, or copies it from other sources. Not surprisingly, then, the evidence base supporting the diagnostic utility of any particular clinical maneuver varies widely. The cervical spinal examination is no exception to this dilemma.

For example, cervical spinal range of motion is perhaps the most commonly performed assessment, common to most if not all practitioners, in the assessment of the patient presenting with neck pain. Notwithstanding the popularity of this examination component, there is a wide range of intra-subject variability depending upon the time of day it is measured. In addition, within a given individual, motion in a particular plane differs according to where the starting point of the motion is measured. Accordingly, establishing normal ranges for spinal motion is challenging.^1,²

This has led to the development of various devices and technologies that can measure spinal range of motion more precisely.³^–⁷ While certain devices have shown improved reliability as compared to manual physical examination techniques, the use of such devices is not commonplace in clinical practice, leaving the practitioner to rely upon manual techniques to guide clinical decision-making.

Compounding these reliability issues is the notion that impaired spinal range of motion correlates with impaired spinal function. In spite of evidence demonstrating a lack of correlation between loss of range of spinal motion and spinal dysfunction,^8,⁹ the use of range of motion as a diagnostic tool remains well engrained in medical culture. Accordingly, range of motion models are regularly used as the basis upon which spinal impairment is rated.

Even more problematic is the attempt to establish whether a particular spinal motion segment, within the multiarticulated spine, has an abnormally restricted or lax range of motion. Despite numerous descriptions of techniques for the palpation of spinal structures, the inter-rater reliability and validity for motion palpation are both lacking in literature support.¹⁰^–¹³

Consequently, there is no evidence-based normative database that represents a gold standard against which any single range of motion data set can be compared to determine whether it is ‘normal’ or not. Moreover, there is no hard and fast rule to determine whether a particular patient’s range of motion values are likely to be clinically relevant, even if they do fall outside the range of ‘normal.’ This example will be discussed in more detail later in this chapter.

The quest for sources of anatomic pain generators has led examiners to teach provocative maneuvers that are designed to provoke local or referred pain.¹⁴ As a result, many syndromic diagnoses have included reproduction of a patient’s habitual pain as an essential diagnostic element. Nevertheless, the combination of the subjectivity of the pain response to palpation and the inherent biases of both examiner and examinee, have limited the predictive value of this aspect of the examination.^15,¹⁶

WHY EXAMINE THE SPINE AT ALL?

The goal of the spinal physical examination is to provide the clinician with clues that support or refute the possible origin of spinal pain and dysfunction. This information is used in conjunction with the history to direct diagnostic testing and treatment to form a clinical report card. When the results of each of these components are concordant, the clinician can be more confident about the certainty of the clinical diagnosis.

In addition, cervical spinal pain can be broadly classified into one of three descriptive diagnostic categories: ominous, neurogenic, and non-specific.

Ominous spinal pain implies a diagnosis with potentially severe adverse health consequences including spinal tumors, infections, fractures, etc. Physical examination often detects focal abnormalities, but is generally insufficient to render a tissue-specific clinical diagnosis.

Neurogenic spinal pain implies a referral from the neural elements including the spinal nerves or spinal cord. In general, these presentations are associated with objective findings more readily and reliably demonstrable on physical examination, including altered spinal reflexes, diminished sensation, weakness on manual muscle testing, and possibly adverse dural tension.

Finally, non-specific spinal pain implies pain of non-ominous and non-neurogenic origin. In general, this diagnostic category is consistent with a more benign prognosis than the other two categories. The anatomic origin, if detectable by alternate means, may be discrete or diffuse. The spinal examination is often non-specific and exhibits wide variability among patients in this descriptive category.

Using this diagnostic frame of reference, the anatomic sources in both ominous and neurogenic spinal pain conditions are readily diagnosed using the clinical report card. In these two categories (neurogenic spinal pain in particular), the physical examination is a very powerful tool in the development of management decisions and in the determination of clinical progress.

However, the same cannot be said for non-specific pain disorders. Here, the physical examination is often insufficiently specific to render an anatomic diagnosis. The reader is referred elsewhere in this text for the specific techniques used to diagnose anatomic pain generators (disc, zygapophyseal joints, etc.).

Nevertheless, there is a role for physical examination, even in this category. Even in the absence of a discrete anatomic diagnosis, function can be assessed either quantitatively or qualitatively by physical examination. In this way the clinician has a measuring stick to use to gauge clinical progress, including response to treatment.

Therefore, the utility of the physical examination of the cervical spine is to provide the clinician with an overall impression of the patient. While individual physical examination maneuvers may be lacking in either sensitivity or specificity, the combination of clinical tests used, in the context of the clinical report card, is meaningful in providing the clinician with evidence to generate clinical hypotheses and working diagnosis upon which to base initial treatments.

Spinal examination is a dynamic process where findings may change over time, either by chance, as a response to intervention (sometimes even despite intervention) or as a reflection of the condition’s natural history. Repeated examinations over time, in the context of the clinical report card, may prove to be the best way to compensate for the deficiencies inherent in the examination process.

In the end, the clinician using physical examination techniques still has to rely somewhat on the art of medicine. The following physical examination protocol is but one of many approaches to clinical examination, and is a synthesis of techniques derived from many sources in the context of the authors’ collective clinical experiences.

PHYSICAL EXAMINATION

Since there is often an overlap in the symptoms associated with upper limb conditions and neck conditions referring to the upper limb, evaluation of the cervical spine should not only include a detailed neurological evaluation of the upper limbs, but also an examination of the upper limb joints that could potentially be the source of the presenting symptoms. Symptoms referable to the shoulder often mirror presenting complaints frequently seen in the cervical spine. The examination of the upper limb joints is outside the scope of the present chapter, so the focus will be on the remaining elements of the cervical spinal evaluation. For further information on the shoulder, please refer to Chapter 49.

The examination of the cervical spine is tailored to the clinical impression presented by the patient’s history. The presence of local or referred pain, motion restriction, guarding, posturing, etc. will influence the emphasis placed by the examiner on various examination techniques.

The various components of the examination should include inspection of posture and musculoskeletal symmetry, evaluation of range of motion in both sitting and supine positions, palpation of the bony and soft tissue structures, and special neural tests. In addition, a detailed neurological examination of the upper limbs must be performed.

Inspection

Inspection should be performed with the patient both standing and sitting. This provides the examiner with the opportunity to evaluate the patient’s habitual posture to look for signs of asymmetry and potential sources of soft tissue overload.

The skin should be inspected for scars, subcutaneous masses, and for lesions that may be consistent with herpes zoster (shingles). Since the thoracic spine is the base of support for the cervical spine, it too should be assessed for scoliosis, kyphosis, and scapular winging. Lastly, station and gait should be screened, specifically looking for signs of spasticity or altered motor tone. Any gait or balance abnormalities may direct further investigation of the central nervous system.

Poor posture, in particular, poor sitting posture, is considered to be a significant contributor in back and neck pain.¹⁷ When sitting in a slumped or unsupported position, there is a loss of lumbar lordosis, which results in a compensatory thoracic kyphosis. Consequently, there is a resultant compensatory forward inclination of the head with flexion of the lower cervical spine and hyperextension of the upper cervical pole to level the head horizontally.

Postural imbalances such as these may impart significant mechanical stress to the cervical spine during sitting. Therefore, it is important to evaluate the patient in both the seated and standing position for compensatory changes in cervical lordosis based on the posture of the lumbar spine.

The head-forward posture is typically associated with ‘rounded shoulders,’ with protracted scapulae and internally rotated shoulders. This is often associated with scapulothoracic muscle imbalance with weakness of the mid and lower trapezius, rhomboids, and serratus anterior, and tightness of the anterior shoulder girdle muscles (pectoralis and latissimus dorsi), upper trapezius, and levator scapulae.

Since many of these muscles have spinal attachments or are innervated by cervical nerves, abnormal scapulothoracic muscle mechanics can alter the mechanics of cervical paraspinal muscles. Over time, substitution patterns develop to compensate for these pathomechanical features, resulting in a vicious cycle of tissue overload often present in local or referred pain.

Diminished cervical lordosis is often the result of paravertebral muscle guarding. This is often a ‘reflex’ response to a variety of possible conditions including muscle overload or a structural abnormality. Altered cervical lordosis should be investigated with a detailed clinical examination and diagnostic imaging, if indicated.

Changes in cervical lordosis may also result from compensation for thoracic or lumbar spine posture. Thoracic kyphosis may arise from weak posterior and tight anterior shoulder and chest wall musculature. However, underlying congenital or developmental structural abnormalities must be excluded. These include Scheuermann’s kyphosis, a hemivertebrae, and scoliosis. Acquired thoracic kyphosis may be a result of fractures, both pathologic and traumatic, as well as infections such as tuberculosis.

In addition, the examiner should look for signs of muscle atrophy and side-to-side asymmetry that may provide clues of the underlying clinical diagnosis. Normal asymmetry such as depressed dominant shoulder needs to be recognized, and, unless extreme in nature, need not raise concern.

Muscle wasting is generally not seen in the neck itself, but rather in the upper limbs, periscapular region, or shoulder girdle. In particular, neurogenic cervical conditions may reveal a myotomal pattern of wasting that provides valuable clues as to the source of anatomic dysfunction.

Muscle atrophy, however, is not always indicative of a neurogenic source. Pain is a powerful inhibitor of function, and therefore disuse atrophy should also be considered when muscle asymmetry is noted.