Cervical Nonorganic Signs: A New Clinical Tool to Assess Abnormal Illness Behavior in Neck Pain Patients: A Pilot Study

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1 170 Cervical Nonorganic Signs: A New Clinical Tool to Assess Abnormal Illness Behavior in Neck Pain Patients: A Pilot Study Jerry B. Sobel, MD, Patti Sollenberger, PT, Richard Robinson, Peter B. Polatin, MD, Robert J. Gatchel, PhD A ABSTRACT. Sobel JB, Sollenberger P, Robinson R, Polatin NATOMIC, NEUROLOGIC, physical, and psychosocioeconomic factors have been shown to affect the reporting of a PB, Gatchel RJ. Cervical nonorganic signs: a new clinical tool to assess abnormal illness behavior in neck pain patients: a pilot study. Arch Phys Med Rehabil 2000;81: back injury or the recovery process after such an injury, but psychosocioeconomic issues predominate. The list includes psychological determinates, 1-14 coping skills, 15 economic issues, 5,7-8 occupational issues, 5,16-22 education and income level, 1,5,18,23 litigation, 9 and nonorganic signs. 3,8,10,11,18,24,25 Two well-done studies highlight the importance of considering psychosocial factors in any back pain evaluation. Gatchel Objective: To develop and assess the reliability of a group of cervical nonorganic physical signs to be used as a simple screening tool for identifying patients with low neck pain who exhibit abnormal illness behavior. Design: Survey, consecutive sample. Data Set: Double masked. Setting: Functional restoration program. Patients: Twenty-six consecutive patients with complaints of chronic neck pain (greater than 4 months duration). Each patient was evaluated by a physician and then again by either a physical or occupational therapist, for the presence of specific cervical nonorganic signs. Both of the evaluations occurred on the same day. Main Outcome Measures: Five categories consisting of eight tests were appraised: (1) tenderness, (2) simulation, (3) range of motion, (4) regional disturbance, and (5) overreaction. Results: The percent agreement between raters ranged from a high of 100% for regional sensory disturbance, to a low of 68% for one of the simulation tests. The average agreement between raters across all of the nonorganic test signs was 84.6%. Likewise, kappa coefficients ranged from 1.00 to.16, reflecting differences in strength of agreement. Conclusion: For many years, the lumbar nonorganic signs (developed by Waddell and colleagues) have been a useful screening tool in the assessment of abnormal illness behavior in the low back pain population. For the first time, a group of cervical nonorganic signs have been developed, standardized, and proven reliable. Key Words: Nonorganic; Neck pain; Back pain; Rehabilitation; Psychosocial by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation From the Productive Rehabilitation Institute of Dallas for Ergonomics Research Foundation (Dr. Sobel, Ms. Sollenberger, Dr. Polatin) and the Department of Psychiatry, University of Texas Southwestern Medical Center (Mr. Robinson, Dr. Gatchel), Dallas, TX; and Sports Orthopedic and Rehabilitation (SOAR)/The Physiatry Medical Group, Menlo Park, CA (Dr. Sobel). Submitted for publication October 20, Accepted in revised form May 21, Presented at the 12th Annual North American Spine Society meeting, October 22-25, 1997, New York, and the Federation of Spine Associations 10th Annual Specialty Day of the American Academy of Orthopedic Surgeons annual meeting, February 16th, 1997, San Francisco. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated. Reprint requests to Jerry Sobel, MD, The Physiatry Medical Group, 2884 Sand Hill Road, #110, Menlo Park, CA by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation /00/ $3.00/0 and colleagues 6 studied 400 US workers presenting to a treatment facility within 6 weeks of their low back injury to determine whether psychosocial factors could predict chronic pain disability at 1 year. Using a combination of pain and disability analogue scores, plus workers compensation and personal injury status, 92.8% of the individuals were correctly classified into working or disabled at 1 year. When the Minnesota Multiphasic Personality Inventory (MMPI) Scale 3 scores (hysteria) were included in the analysis, 90.7% of the patients were accurately classified. A powerful discrimination model was developed to predict long-term low back pain disability without the use of physical measures, further emphasizing the crucial role of psychosocial factors in the recovery process. Waddell and associates 11 evaluated 200 back pain patients referred to an orthopedic clinic or problem referrals to a regional back clinic. All patients underwent full clinical, physical, and psychologic assessment. As part of that study, all patients were evaluated for the presence of inappropriate symptoms and signs suggestive of psychosocial distress. Factors influencing disability were analyzed, and physical impairment accounted for less than one half of the total disability scores (40.3%), while psychological distress and magnified illness behavior (ie, inappropriate symptoms and signs) explained 30.9% of the variance in low back disability. These data suggest that disability in patients with low back pain is multifactorial and must be evaluated in terms of psychosocial distress and illness behavior, as well as actual physical impairment. Nonorganic symptoms and signs have been described in the medical literature dating back to the early part of the twentieth century, 26,27 and were initially felt to be an indication of malingering. As medical research advanced, however, it became apparent that these symptoms and signs were more closely correlated with psychological distress and abnormal illness behavior rather than malingering. 2,10,24 Brown and colleagues 2 devised six criteria that revolved around patients attitudes toward their symptoms, treatment, and their reaction to illness, in an effort to identify a psychogenic component of illness. Criteria included: (1) a history of the present illness that is vague because of confused chronology and nonrelevant details; (2) expression of either open or veiled resentment toward, and criticism of, the doctors and ancillary personnel for alleged mismanagement or neglect; (3) dramatic descriptions of the symptoms and the patient s reactions to them; (4) difficulty in localization and description of pain and other symptoms; (5) failure of the usual forms of treatment to give significant relief from pain; (6) accompanying neurotic symptoms. The authors

2 CERVICAL NONORGANIC SIGNS, Sobel 171 concluded that in patients with four or more of these symptoms, the presence of complicating psychological factors in the illness was likely; in those with two or less, psychological factors were not important. In 1979, the Volvo award in clinical science was awarded to Waddell and colleagues for their article, Nonorganic Physical Signs in Low Back Pain. 10 Theirs was the first study to develop, standardize, and demonstrate the reliability of a group of lumbar nonorganic physical signs. Three hundred fifty British and Canadian patients were evaluated for the presence of eight nonorganic signs in five categories. The five categories and eight signs are: (1) tenderness (superficial or nonanatomic); (2) simulation (axial loading, rotation); (3) distraction (straight leg raising); (4) regional (weakness, sensory disturbance); (5) overreaction to examination. In 50 Canadian patients admitted to the back assessment and rehabilitation clinic of the workers compensation board for finalization of prolonged disability, the reliability of these signs between two examiners was determined. The patients were first examined on the day of admission, and then were reexamined on a different day within 1 week by the second examiner. The reliability of the eight nonorganic signs ranged from 78% to 86%, with multiple nonorganic signs showing the highest reproducibility of 86%. In a separate part of the study, 84 postoperative patients were found to have a low but consistent correlation with the neurotic triad on the MMPI (ie, Scales 1, 2, and 3), which is considered to be a nonspecific general measure of psychological distress. Furthermore, in another subset of patients, multiple nonorganic signs correlated closely with a surgeon s rating of overall psychological unsuitability. Other studies have also shown a correlation between these nonorganic signs and the first three scales on the MMPI. 24,28 One important point stressed by the authors is that the presence of nonorganicity on examination does not preclude the presence of significant concurrent organic pathology, and therefore, each patient must be thoroughly assessed. The nonorganic physical exam tests, as described above, have become an invaluable, simple, and rapid clinical screening tool to identify those patients that may need a more comprehensive evaluation of psychosocioeconomic factors that potentially affect recovery. 10,29,30 To date, there has not been a description of cervical nonorganic signs. The purpose of this study was to develop a set of cervical nonorganic physical signs, and to test their interexaminer reliability. The lumbar nonorganic signs developed by Waddell 10 were used as a starting point, and for those that could not be extrapolated to the cervical spine or upper extremities, new tests were developed. This is the first part of an ongoing research project to develop, standardize, and determine the overall usefulness of a set of cervical nonorganic signs in clinical practice. MATERIALS AND METHODS Subjects Twenty-six consecutive patients with chronic neck pain (20 men and 6 women) who were referred to a functional restoration program were selected for the study. The average age of the subjects was years (range, 28 to 61), and their average length of disability was months (range, 0.4 to 25). Patients were referred from physicians, nurse case managers, and insurance companies because they had failed to respond to primary and secondary level rehabilitation and/or surgical care for their neck pain. Procedure As part of their initial evaluations, each patient underwent a complete history and physical examination with special emphasis on the musculoskeletal and nervous system of the cervical spine and upper extremities. In addition to the standard exam, each patient was evaluated for the presence eight cervical nonorganic signs (described below). After the physician evaluation, either a physical therapist or occupational therapist reevaluated each subject for the presence of these specific physical signs. All physicians and therapists were trained to perform the nonorganic tests by one of the authors (JS). A standardized evaluation form was developed for the study. If the patient exhibited a positive sign, it was recorded as such and the number of positive signs was totaled and compared to the subsequent evaluation. For statistical purposes, each positive test was compared between examiners. Examination Technique A standardized set of eight physical examination signs, classified into five categories, was developed for this study. As a starting point, some of Waddell s lumbar nonorganic signs were extrapolated to the cervical spine, and an additional three signs were specifically developed for this project. The eight signs and five categories are as follows (table 1). Tenderness. Superficial. Examiner palpates the cervical spine region, comprised of the posterior aspect of the cervical and upper thoracic spine. See table 1 for criteria for a positive test. Nonanatomic. The areas of the cervical, thoracic, lumbar, and brachial regions are deeply palpated. If the patient also had concomitant low back pain, then pain on deep palpation of the low back was discounted and the region of the arm was added to the criteria (table 1). Simulation. When a simulation test is performed, the patient is under the assumption that the painful area is being tested when, in reality, it is not. A test is considered positive if the subject reports pain with the physical exam maneuver. Head/shoulder/trunk rotation in the sitting position. With the patient sitting on the examination table, facing the examiner, the clinician rotates the patient s trunk to the right and left using the patient s shoulders. Care must be taken to observe that the patient is rotating his or her head in the same plane as the shoulders. Head/shoulder/trunk/pelvis rotation while standing. Similar to the sitting test, the examiner rotates the patient s shoulders, trunk, and pelvis to the right and left as one unit. Care must be taken to observe that the patient is rotating his or her head in the same plane as the shoulders/trunk/pelvis (figs 1, 2; table 1 for positive test). Range of motion. Cervical rotation. The examiner asks the seated patient to rotate his or her head as far as possible to the right and then left (figs 3, 4; table 1 for positive test). This test was devised based on the fact that the majority of cervical rotation occurs in the upper cervical spine, and the majority of cervical spine lesions are in the mid to lower cervical spine. Regional disturbance. For motor or sensory changes to be classified under this category, the deficit has to fall out of what is considered normal neuroanatomy. For example, a patient who reports loss of sensation involving half of the body or an entire upper extremity would be considered to fall into this category as long as multiple nerve root or peripheral nerve injury has been ruled out. It must be emphasized that care must be taken to rule out multiple nerve root or peripheral nerve injuries before considering that either or both of the regional disturbance subcategories are positive.

3 172 CERVICAL NONORGANIC SIGNS, Sobel Palpation Superficial tenderness Nonanatomic tenderness Table 1: Reliable Cervical Nonorganic Signs and the Criteria for a Positive Test Sign Test Site Criteria for a Positive Test Palpation of cervical spine region and upper thoracic region Deep palpation of the cervical, thoracic, lumbar, and brachial regions Patient complains of pain with light touch or light pinching of the skin Patient complains of widespread tenderness, ie, outside of the cervical and upper thoracic region Simulation Rotation of head/shoulders/trunk/pelvis while standing Examiner rotates patient s head, shoulders, trunk, and pelvis Patient complains of neck pain with rotation. Cervical Range of Motion Patient rotates head as far as possible to the right and then left Rotation is less than 50% of normal in each direction Regional Disturbance Sensory loss Light touch or pinprick Patient reports diminished sensation in a pattern that does not correspond to a specific dermatome of a nerve root(s) or peripheral nerve(s) Motor loss Formal manual muscle testing, observation Weakness detected in a nonanatomic pattern; the hallmark being giveway weakness Also positive if patient is observed to have normal muscle strength but on formal test exhibits weakness Overreaction Examiner s observation Examiner feels the patient is overreacting during the examination. Reliable behaviors include: 1. Moderate to extremely stiff, rigid, or slow movements 2. Rubbing the affected area for more than 3sec 3. Clutching, grasping, or squeezing the area for more than 3sec 4. Grimacing due to pain 5. Sighing Sensory loss. For this test to be considered positive, the patient must report diminished sensation to either light touch or pinprick in a pattern that does not correspond to a specific dermatome of a nerve root(s) or peripheral nerve(s). Frequently, patients will report loss of sensation of the entire upper extremity, or below the elbow. Motor loss. On formal manual muscle testing, weakness is detected in a nonanatomic pattern. The hallmark of this test is giveaway weakness. In addition, a test would also be considered positive if, on observation, the patient demonstrates normal muscle strength, but on formal testing exhibits weakness. As an example, the patient uses his or her elbow extensors to get up onto the examination table, but is then noted to have less than antigravity strength on manual muscle testing of the elbow extensors. Overreaction. In this study, this category was considered positive if the examiner felt that the patient was overreacting during the examination. See table 1 for examples of overreaction. For the clinician, this is a very subjective category, and therefore, care must be taken not to let one s own emotional feelings about the patient interfere with the assessment of whether or not the patient is overreacting to the examination. In addition, the examiner must take into account that there can be a considerable degree of cultural variation in the response to painful maneuvers. 25 Scoring Criteria A standardized evaluation form was developed for the study. If the patient exhibited a positive sign, one point was given for that sign. It was possible for a patient to exhibit all eight signs. Total and individual scores were then compared between physicians and therapists for reliability of these nonorganic signs. RESULTS Table 2 presents the average percent agreement between examiners, and the kappa coefficients, for each cervical nonorganic sign. The comparison was made between the physician evaluation and that of the physical or occupational therapist. The percent agreement ranged from a high of 100% for regional sensory disturbance, to a low of 68% for the simulation test of rotating the head, shoulders, and torso in the sitting position. The kappa coefficients, likewise, ranged from a high of 1.00 to a low of.08. Complete agreement was recorded for regional sensory disturbance, and slight strength for the simulation test done in the sitting position and the overreaction signs of disproportionate verbalization and muscle tension. The average percent agreement between raters across all of the nonorganic test signs was 84.6%. Table 3 presents the average percent agreement and kappa values between examiners for patients that presented with one

4 CERVICAL NONORGANIC SIGNS, Sobel 173 or more signs, two or more signs, and so forth. As can be seen, for subjects presenting with two or more signs or greater, the agreement was quite high. This was also true when looking at the kappa coefficients. Fig 2. Rotation simulation test, with patient being rotated to the right as far as possible until patient reports pain (the head, shoulders, and pelvis are rotated in the same plane while standing). Fig 1. Rotation simulation test, with examiner preparing patient for rotation while patient is standing. DISCUSSION This is the first study to develop, standardize, and determine the interrater reliability of a group of cervical nonorganic signs. As a starting point, the lumbar nonorganic signs were used. The authors determined which signs could be easily extrapolated to the cervical spine, and for those that could not (eg, distraction straight leg raising), a new sign was developed. The average agreement between raters across all the nonorganic signs was found to be 84.6% (range, 68% to 100%). The highest percent agreement was for the regional disturbances sensory category at 100%, and the lowest was 68% for distraction test of rotation in a seated position. The kappa coefficients were essentially the same, with some exceptions. Those demonstrating only slight strength were simulation while sitting and overreaction (disproportionate verbalization and muscle tension). Such data suggest dropping these three signs, while keeping the others. There is another reason to recommend dropping the simulation test performed while in the sitting position. First, we found that it was the hardest test to perform. Often, it was difficult to get patients to rotate their heads in the same plane as the shoulders and torso, thus requiring that the test be repeated. Furthermore, it had the lowest percent agreement and kappa coefficient of all the cervical nonorganic signs. Table 1 presents those cervical nonorganic signs that we have established as being reliable between examiners. Waddell found the interrater reliability of the lumbar nonorganic signs to range from 78% to 86%. Kappa coefficients were not reported. Thus, our results for cervical nonorganic signs are comparable. Moreover, we found that as the number of signs increased in any given patient, the agreement between examiners also increased, from a low of 77% for one or more signs to a high of 92% for five signs. The lumbar nonorganic signs have become a mainstay in the clinical examination of the low back pain patient. When used properly, they can help identify those patients with underlying significant psychological distress. 10,30 There have been many studies that have found that the presence of nonorganic behavior in general, and the Waddell signs in particular, are predictors of suboptimal surgical and rehabilitation outcomes, 3,25,29,30-34 and their presence is associated with higher costs and greater lengths of disability. The authors believe that the cervical nonorganic signs can be equally as valuable. Werneke and colleagues 30 conducted a prospective study of 187 chronic back pain patients enrolled in a work-oriented physical rehabilitation program. Patients were screened at initial evaluation and program completion for the eight lumbar nonorganic signs. The principal outcome measure was either return to work or change in work status (eg, patients working part time/light duty improving to full-time/full duty). A patient was considered a success if he or she either returned to work or showed work status improvement. At program completion, there were 115 successes and 55 failures; 13 patients were not re-evaluated at program completion. In every instance, the failure group had a higher number of nonorganic signs. In addition, at least one sign was present at discharge in 47% of the failure group versus 12% of the successes. Eighty-two percent

5 174 CERVICAL NONORGANIC SIGNS, Sobel Table 2: Average Percent Agreement and Kappa Coefficients Between Examiners for Each Cervical Nonorganic Sign % Agreement Kappa* Palpation Superficial tenderness Nonanatomic tenderness Simulation Head and shoulders rotated (sitting) Head, shoulders, and pelvis rotated (standing) Range of motion (cervical rotation) Regional disturbances Weakness Sensory Overreaction Stiff movement Rubbing area Clutching area Grimacing Sighing Disproportionate verbalization Muscle tension * Kappas of 0 to 0.2 have slight strength,.21 to 0.4 have fair strength,.41 to 0.6 have moderate strength,.61 to 0.8 have substantial strength, and.81 to 1.00 have almost perfect strength of agreement. There was total agreement between raters for all rated signs. Fig 3. Initial assessment of cervical range of motion while in seated position baseline measure. of those in the successful group had a reduction in the number of behavioral signs from 71% to 0%, while only 44% of the failures reduced their signs (ie, only 21% reduced the number of signs to zero). Two studies evaluated the relationship between lumbar nonorganic signs and performance on physical capacity tests. Cooke and colleagues 32 demonstrated that those patients with three or more Waddell signs had lower performance values on serial lumbar dynamometer testing than those patients with two or less. Hirsch and coworkers 35 found similar results in a group of 85 men, aged 18 to 60 years, who had had low back pain for longer than 5 weeks. Patients with three or more Waddell signs performed significantly less well on almost all physical tests. Surgical outcome has also been shown to be influenced by the presence of nonorganic behavior. Waddell and colleagues 29 studied 185 white, native-born British patients before and after spine surgery. Nonorganic behavior was evaluated by recording inappropriate symptoms, signs, and by a pain diagram. The inappropriate symptoms were whole leg pain, whole leg numbness, whole leg giving away, pain at the tip of the tailbone, complete lack of pain-free intervals, intolerance to treatment, and emergency admissions to the hospital for back pain. 11 Inappropriate signs were quantified by the lumbar nonorganic signs. 10 The most important psychological factors found to affect surgical outcome were preoperative measures of inappropriate symptoms and inappropriate signs, increased bodily awareness, and depressive symptoms. Finally, a recent study by Gaines and Hegmann 36 highlights the importance of identifying Waddell signs in acute occupa- Table 3: Average Percent Agreement Between Examiners For Patients With Differing Number of Signs % Agreement Kappa Fig 4. Again, while in a seated position, the patient is asked to rotate her head as far as possible to the right to measure cervical range of motion. One or more signs Two or more signs Three or more signs Four more signs Five or more signs

6 CERVICAL NONORGANIC SIGNS, Sobel 175 tional low back pain. They found that in those patients with even one nonorganic sign, the median time to return to work was almost four times as long (58.5 vs 15 days), and those same patients had more physical therapy and computed tomography. CONCLUSION The lumbar nonorganic signs have certainly been shown to be a reliable clinical tool in the assessment of the patient with back pain. It is the hope of the authors that these cervical nonorganic signs will be as valuable in the assessment of neck pain patients. Ongoing research will further develop, standardize, and determine the use of these signs in clinical practice. Finally, a word of caution should be noted. Only one nonorganic sign in isolation from others may be present in some organic conditions, and should therefore be discounted (ie, multilevel dermatomal sensory loss in peripheral neuropathy or multilevel stenosis). References 1. Strand NE. 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