Chapter 5 Palpatory Diagnosis of Subluxation

Palpation, motion palpation, joint play, end feel, reliability

After reading this chapter you should be able to answer the following questions:

Question 1	What are the three most frequently cited adjustive indicators evaluated by palpation?
Question 2	What is the reliability of spinal palpation?
Question 3	What strategies can be used to improve the reliability of palpatory procedures?

The hands are the primary tool of the chiropractor and are of utmost importance in identifying subluxation. The origin of the term chiropractic is the Greek cheiroprattien (done by hand), and current texts used in chiropractic education are replete with comprehensive palpatory techniques.¹^–⁴ Manual therapies are, however, not unique to chiropractic.

Historically, manual therapies can be traced to Eastern and Western cultures thousands of years before the advent of chiropractic.⁵ Hippocrates was a notable proponent of manual treatment, particularly for spinal conditions such as scoliosis and subluxation.^5,⁶

In light of modern advances in diagnostic imaging and other procedures, it may seem that the tedious process of palpation to evaluate the neuromusculoskeletal system is outdated. However, palpation remains recognized as an essential skill by disciplines such as osteopathy ⁷ and physical therapy,^8,⁹ which employ many techniques quite similar to those used by chiropractors. Beal,⁷ an osteopath, notes that “palpation is of prime importance in diagnosis, manipulative treatment, and prognosis” of musculoskeletal conditions. Magee⁹ describes numerous static and dynamic palpatory procedures for spinal and extremity articulations.

In quite another realm, Goble ¹⁰ offers practical advice for purchasing a horse. He states that

with recent advances in diagnostic techniques…there is a tendency to reduce our reliance on the most important part of purchase evaluation of the horse, the hands-on physical examination.

Human parallels are obvious in our age of cost-conscious health care, in which a thorough physical examination may render more useful information than expensive diagnostic tests.

History of Palpation in Chiropractic

Because the use of diagnostic palpation has stood the test of time, a brief review of its history in the chiropractic profession is of interest. In 1912 Gregory ¹¹ defined palpation as “the gentle application of the hand or fingers to the surface of the body for the purpose of determining the condition of the surface and adjacent parts of a certain locality or organ of the body.” He described palpable characteristics of the “spinal lesion” as follows:

1. Pain

2. Tender nerves

3. Thermic alterations

4. Congested neural cords

5. Contractured or contracted muscle

6. Spinous process malposition

7. Transverse process malposition

A contemporary study by Keating et al.¹² to evaluate interexaminer reliability of currently used palpation procedures showed remarkable similarity to indicators listed in 1912, with the addition of a dynamic component:

1. Osseous pain

2. Soft tissue pain

3. Temperature difference

4. Visual observation

5. Passive motion palpation

6. Muscle tension palpation

7. Active motion palpation

8. Misalignment palpation

Among the earliest chiropractic palpation techniques was nerve tracing, defined as

the art of following, by palpation, a tender nerve from its spinal origin to some inflammatory or pathological lesion or zone, or the act of tracing a tender spinal nerve from an inflammatory zone back to its spinal exit.¹¹

D.D. Palmer ¹³ identifies himself as the originator of nerve tracing, but B.J. Palmer¹⁴ also wrote extensively on the subject. According to B.J. Palmer, methodologic consistency and reliability appear to have been recognized as a problem even in his day (early twentieth century) shown by his observation that

so far all of the nerve tracing in chiropractic, while it has been excellent, has produced excellent results—has been used by many chiropractors with a large degree of success—has still shown a remarkable divergence of method and accuracy.¹⁴

It is interesting that early nerve tracing was not unique to the chiropractic profession. Cyriax, a medical doctor, published a paper on “nerve palpation” in 1914.¹⁵ Nerve tracing is no longer emphasized in chiropractic education.

In addition to the aforementioned static palpation techniques, various dynamic forms of palpation have developed within the chiropractic profession. Gillet ¹⁶^–¹⁸ developed and systematized motion palpation techniques that have been expanded and disseminated by Faye^2,^19,²⁰ and Schafer.²⁰ Palpation is currently defined as the application of manual pressures through the surface of the body to determine the shape, size, consistency, position, and inherent motility of the tissues beneath.²¹

Palpatory Indicators for Manipulation

Contemporary palpation techniques can be divided into static and motion procedures used in the adjustment decision-making process ^1,⁴:

Of the aforementioned palpatory techniques, some seem to be emphasized more than others. Bryner ²² surveyed 27 manuals and texts from chiropractic, osteopathic, physical therapy, and medical sources. He reported the frequency of citation of 15 different indicators for knee manipulation. He found the three most frequently cited indicators to be: (1) joint play abnormality, fixation, adhesion, tissue tension; (2) misalignment, displacement, prominence; and (3) tenderness, swelling.

He concluded that “more consensus between professional groups exists than is suggested in most professional forums.” A survey of chiropractic colleges ²³ found that all of the respondents (9 of 18 colleges surveyed) reported using joint play assessment and motion palpation as important indicators for joint manipulation. It was further concluded that improved standardization of procedures is needed, a concern also noted by others.^8,²⁴^–²⁷

Previous mention was made of selection of palpatory techniques that identify manipulable subluxation or manipulable lesion. Jull, Bogduk, and Marsland ²⁸ looked at this issue, as well as the accuracy of manual diagnostic techniques for specific localization of cervical zygapophyseal pain and dysfunction. The three palpatory criteria selected were: (1) abnormal end feel, (2) abnormal quality of resistance to movement, and (3) local pain on palpation.

This study was unique in many respects. First, its subjects were 20 patients with chronic (more than one year) neck pain. Second, they were evaluated with diagnostic nerve blocks to establish with certainty the vertebral level of their symptoms and that the zygapophyseal (facet) joints were indeed the source of pain. Third, the examiner blindly examined the subjects either before or after the diagnostic nerve block (1) to establish if the pain was the result of facet joint dysfunction; (2) if so, to identify the precise level of pain; and (3) to identify patients with nonfacet pain. The results were as follows:

1. The examiner correctly identified 15 of 20 patients with confirmed facet pain or dysfunction.

2. The correct segmental level was identified in all 15 patients.

3. Five patients with confirmed nonfacet pain were correctly identified.

4. It was concluded that “manual diagnosis by a trained manipulative therapist can be as accurate as can radiologically-controlled diagnostic nerve blocks in the diagnosis of cervical zygapophyseal syndrome.”²⁸

5. The three diagnostic indicators chosen were “highly specific for symptomatic zygapophyseal joints.”²⁸

These results are quite impressive, and although they have been replicated in the cervical spine (see Chapter 17), they cannot be generalized to other areas of the spine. Still they invite a closer look at the issue of reliability as it relates to palpation procedures.

Test Reliability

Background

Reliability is the reproducibility or consistency of measurement or diagnosis.²⁹^–³¹ It is the extent to which a test can produce the same result on repeated evaluation of an unchanged characteristic. When a test result is categorical in nature, such as the decision of whether to perform an adjustment, reliability is also called chance-corrected agreement or concordance.

Reliability evaluation is only one step in the determination of the clinical usefulness of a diagnostic or evaluative procedure.^32,³³ The accuracy or validity of a procedure—to what degree the test is on the mark and to what degree it actually evaluates what is intended—is of paramount importance. Direct assessment of the validity of adjustive indicators has remained elusive because of the absence of a “gold standard” for identifying manipulable subluxation. Reliability assessment thus continues to be the primary research being conducted on the clinical usefulness of palpation. Although strong consistency of measures does not ensure validity, reliability assessment is extremely important because it estimates the contribution of a test itself to the clinical decision-making process beyond what would be expected by examiner guessing or random measurement error.³⁴

Assessment

Reliability is evaluated by multiple blinded measurements performed on a sample of subjects. There are several types of reliability relevant to palpation (Table 5-1). Interexaminer reliability evaluates the consistency of different examiners and is determined through repeated assessment by two or more raters. Intraexaminer reliability is a measure of self-consistency; each rater must perform at least two measurements. Intraexaminer reliability is susceptible to overestimation because of difficulty of blinding the rater³⁵ and a tendency toward consistency of measurement error.³⁶

^{Table 5-1} Types of Reliability

Type	Evaluation
Interexaminer	≥ 2 raters
Intraexaminer	≥ 2 times
Interinstrument	≥ 2 instruments
Test-retest	≥ occasions

Interinstrument reliability evaluates the agreement between two diagnostic techniques or two instruments (same type or different kinds). For example, the reproducibility of pain thresholds by two different types of pressure algometer can be evaluated. Intertechnique reliability can be assessed only if both instruments use the same units of measurement.

Test-retest reliability seeks to determine if examiners or instruments are consistent over time. Measurement of this type of reliability is problematic because the stability of manipulable subluxation and other palpatory entities is largely unknown. Biomechanical changes may be responsible for any apparent lack of consistency over time.

Reliability Indices

The choice of the most appropriate reliability statistic depends on the type of measurement being made (Table 5-2). Although other statistical measurements have been used, they tend to give ambiguous results; in-depth discussions of reliability statistics may be found elsewhere.²⁹^–³¹

^{Table 5-2} Reliability Statistics

Scales and Indices
Nominal	Kappa
Ordinal	Weighted kappa
Interval	Intraclass correlation
Strength of Agreement
0.0	Chance
0.00-0.39	Poor-fair
0.40-0.59	Moderate
0.60-1.00	Good-excellent
1.00	Perfect