Research Review by Dr. Kent Stuber©

Date:

Apr. 2008

Study Title:

Assessment of neck pain and its associated disorders: Results of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and its Associated Disorders

Authors:

Nordin M, Carragee EJ, Hogg-Johnson S, et al

Authors’ Affiliations:The Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders.
  • Nordin – Departments of Orthopaedics and Environmental Medicine and Program of Ergonomics and Biomechanics, School of Medicine and Graduate School of Arts and Science, New York University; Occupational and Industrial Orthopaedic Center, New York University Medical Center
  • Carragee – Department of Orthopaedic Surgery, Stanford University School of Medicine; Orthopaedic Spine Center and Spinal Surgery Service, Stanford University Hospital and Clinics
  • Hogg-Johnson - Institute for Work and Health, Toronto; Department of Public Health Sciences, University of Toronto

Publication Information:

Spine 2008; 33(4S): S101-S122.

Summary:

The Neck Pain Task Force (NPTF) evaluated articles on assessment of neck pain and associated disorders from two perspectives:
  1. The emergency room clinical assessment
  2. The non-emergency clinical assessment (this is likely of more interest for most Research Review Service readers, and will be the focus of this review)
Briefly, there are a few TERMS that readers will need to bear in mind when reading about research related to diagnostic testing:
  • Validity – the accuracy of a test, generally compared with a gold standard.
  • Sensitivity – a measure of validity, the percentage of disease positive patients who will have a positive test result.
  • Specificity – a measure of validity, the percentage of disease negative people who will have a negative test.
  • Positive predictive value – a measure of validity, the likelihood that a person has a condition if they have a positive test result.
  • Negative predictive value – a measure of validity, the likelihood that a person does not have a condition if they have a negative test result.
  • Reliability – essentially the consistency of a test, essential for validity. Can be intra-observer (same observer repeated) or inter-observer (looking for consistency between observers).
  • Phase I studies of a diagnostic test – look for differences between affected and unaffected individuals on a test.
  • Phase II studies – evaluate if certain test results mean a patient is more likely to have a target disorder.
  • Phase III studies – look to see if a test distinguishes those with or without a target disorder in those one might suspect of having the disorder.
  • Phase IV studies – evaluate if patients with the disorder who take a certain test have better health outcomes than those who have not had the test.
In their literature search, the NPTF identified 95 admissible studies related to diagnosis and assessment of neck pain and associated disorders.

With respect to non-emergency clinical assessments, no studies were identified on taking a patient history, however the NPTF advocates the use of a “Red Flag” system akin to that which clinicians will be familiar with when evaluating patients with low back pain to help rule out serious conditions (including but not limited to: trauma, pathological fracture, tumor, cord compromise due to cervical myelopathy, systemic diseases, infection, intractable pain, and prior medical history including neck surgery).

With respect to the clinical assessment in non-emergency situations, 63 admissible studies were identified. Reliability of the entire clinical examination is generally low and not well studied as only one study looked at the effect of a composite of examination procedures.

Inter-examiner reliability for visual inspection varied from fair to excellent and improved as the level of disease prevalence decreased. Range of motion testing of the neck was evaluated in 15 studies: inter-rater reliability varied from slight to moderate, visual estimation by the clinician was deemed as reliable as using an external device (such as a CROM). Muscle strength was evaluated in 7 studies and showed slight to moderate inter-examiner reliability. Cervical flexor endurance was found to distinguish well between WAD II patients and healthy controls.

Seven studies looked at palpation: inter-examiner reliability of trigger point assessments was found to be fair to moderate; using an algometer increased reliability for a trigger point assessment from moderate to excellent.

Provocation tests for neck pain with radicular involvement have been evaluated in 3 studies, and have been found to have high predictive values when compared with a gold standard. Contralateral rotation of the head and extension of the arm and fingers in particular has high accuracy for identifying cervical root irritation with sensitivity ranging from 0.77 to 0.90 and specificity ranging from 0.22 to 0.94. Evaluating for non-organic signs in patients with chronic neck pain had high inter-rater reliability.

Blood testing, functional testing (lifting, stepping, walking), and manipulation and mobilization testing for diagnostic purposes all displayed varying levels of reliability.

Electrodiagnostic testing including EMG have been subject of numerous studies. Needle and surface EMG have each been the gold standard in 3 studies respectively, and no conclusions could be drawn from them until further high level research is conducted. The NPTF notes that the American Academy of Neurology has found surface EMG to be an unacceptable clinical tool in the evaluation of patients with low back pain, and it appears that they feel that this statement could be repeated in the neck.

The reliability of MRI reading for degenerative or pathologic findings was rated as moderate, and the NPTF note that positive MRI changes in the cervical spine were common in asymptomatic patients, and that trend increases significantly with age. There are no apparently unique findings on MRI for patients with benign WAD when compared with controls.

The NPTF noted that questionnaires cannot establish a diagnosis, but they can be useful for determining neck pain impact, monitoring change in condition, establishing functional deficits and/or psychomotor status, and they may be helpful for choosing treatments. 19 studies on 13 different questionnaires were admitted by the NPTF. The Visual Analog Scale (VAS) is the most commonly cited pain measure – it is easy to use and has good psychometric properties, often being used as the gold standard against other questionnaires for evaluation of pain and function/disability. The Neck Disability Index (NDI) was found to be the most valid of the tools reported for measuring pain and it has moderate to good agreement with the SF-36. The NDI has been used as a gold standard for assessing function/disability related to neck pain.

Conclusions & Practical Application:

Based on their evaluation of the literature, the NPTF make the following clinical recommendations for non-emergency assessment of neck pain. These will be divided into Do’s and Don’ts along with the level and type of evidence. My comments appear in italics:

DO:
  1. Use manual provocation tests of the neck and upper extremities for suspected cervical radiculopathy (to rule it in) (strong evidence). Having attended the initial release of the NPTF findings in Saskatchewan, a comment was made by the speakers that they felt contralateral rotation of the neck (away from the side with the suspected radiculopathy) with extension of the arms and fingers was likely the best test to employ to confirm a suspected radiculopathy.
  2. Conduct a musculoskeletal and neurological exam to rule out structural lesions or neurological conditions (as opposed to confirming the presence of conditions) (moderate evidence).
  3. Evaluate sensitivity to touch (light touch and pin prick) (moderate evidence). This would be in patients with suspected neurological compromise.
  4. Evaluate range of motion (weak evidence) – It does not appear to matter if the range of motion is assessed by the clinician or subjectively reported by the patient. Use of a device (ex. CROM) does not appear to improve results. In Saskatchewan comments were made that range of motion does not have great diagnostic utility, but it is still a test that clinicians should likely conduct to assess the impact of injury.
  5. Palpate for trigger points (weak evidence). Use of an algometer appears to improve reliability. It is interesting to note that there have been no studies on general muscular palpation. It is also interesting that no comments were made on additional palpatory testing such as static or motion palpation.
  6. Evaluate for non-organic causes (moderate inconsistent evidence). This would likely be only in chronic cases or in those where some form of psychosomatic manifestations could be possible.
  7. Test muscle strength (weak inconsistent evidence). This applies to testing of the neck.
  8. Conduct functional tests (weak inconsistent evidence).
  9. Inspect the patient for abnormal signs. This is of course part of any musculoskeletal examination.
  10. Use needle EMG to diagnose the cause and site of cervical radiculopathy. This would require a referral for most manual therapists of course. MRI could also be used in this scenario and CT is beneficial for identifying suspected locations of stenosis.
  11. Use patient self-assessment questionnaires giving particular consideration to neck-specific questionnaires to routinely evaluate neck pain patients in terms of pain, disability/impact, function, and psychosocial status. No specific recommendations were made in Saskatchewan, but one might imagine from the amount of research done on the VAS and NDI that they might be the most logical questionnaires to consider. They are easy to complete for the patient and easy for the clinician to interpret. It is strongly recommended that all clinicians begin some form of paper-based outcomes assessment if they do not already.
DON’T:
  1. Use manipulation as a diagnostic test (strong evidence). This statement would seem self-explanatory to any manual therapist as it would be difficult to imagine using a treatment as a diagnostic test, regardless this was actually done in one study.
  2. Use injections (facet or medial branch blocks) in chronic neck pain (moderate evidence). Again not an issue for most manual therapists.
  3. Do routine blood tests (weak evidence). Again not an issue for most manual therapists.
  4. Use MRI in all evaluations (weak evidence). Again not an issue for most manual therapists.
  5. Employ discography (weak evidence). Again not an issue for most manual therapists.
  6. Do nerve conduction testing (weak evidence). Again not an issue for most manual therapists.
  7. Evaluate for cervical lordosis/kyphosis (weak evidence).
  8. Conduct CT scan for nerve involvement (weak evidence). Again not an issue for most manual therapists.
  9. Conduct surface, dermatomal, or quantitative sensory electrophysiological studies (including surface EMG) for routine evaluation of neck pain. Again not an issue for most manual therapists, although the prevalence of surface EMG in clinical settings has increased in recent years. The NPTF indicated in Saskatchewan that routine use of sEMG particularly in non-radicular cases was inappropriate.
  10. Conduct routine x-rays in non-emergency situations in those not suspected of having a major structural disease. This may prove to be a contentious issue for some therapists as their particular techniques may warrant the use of x-rays on all patients. The NPTF feels that based on the evidence that this is unnecessary.
  11. Use patient self-assessment questionnaires to diagnose a patient’s condition.
It is interesting to note that for the vast majority of neck pain patients that diagnosis can be rendered without the use of any imaging or laboratory testing. For patients with neck pain only (no suspected radiculopathy), the physical examination could potentially be streamlined considerably to include inspection, ranges of motion, palpation, muscular strength, and a general neurological and musculoskeletal exam. In patients with suspected radiculopathy, adding manual provocative tests and evaluating sensitivity to touch appear beneficial in rendering a diagnosis. Of course, to review, the NPTF recommend classifying neck pain into four grades similar to those used in WAD as set out in the Quebec Task Force Classification. They are as follows:
  • Grade I neck pain is neck pain and associated disorders with no signs or symptoms suggestive of major structural pathology and no or minor interference with activities of daily living.
  • Grade II neck pain indicates no signs or symptoms of major structural pathology, but major interference with activities of daily living.
  • Grade III neck pain indicates no signs or symptoms of major structural pathology, but presence of neurologic signs or nerve compression such as decreased deep tendon reflexes, weakness, or sensory deficits.
  • Grade IV neck pain indicates signs or symptoms of major structural pathology.
Having only these four grades of neck pain to sort patients into does simplify the diagnostic process considerably, but as we will see when looking at the NPTF’s evaluation of treatments of neck pain, having the correct grade of neck pain is important as it will help the clinician select the treatment(s) most likely to help the patient in question.