Research Review by Dr. Kent Stuber©

Date:

Feb. 2008

Study Title:

  1. A new conceptual model of neck pain. Linking onset, course, and care.
  2. Methods for the best evidence synthesis on neck pain and its associated disorders.
  3. Research priorities and methodological implications
  4. Clinical practice implications of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associate Disorders. From concepts and findings to recommendations

Authors:

  1. Guzman J, Hurwitz EL, Carroll LJ, et al.
  2. Carroll LJ, Cassidy JD, Peloso PM, et al.
  3. Carroll LJ, Hurwitz EL, Cote P, et al.
  4. Guzman J, Haldeman S, Carroll LJ et al.

Authors’ Affiliations:

The Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders.
  • Guzman J – Department of Medicine, University of British Columbia, Occupational Health and Safety Agency for Healthcare in BC
  • Carroll LJ – Department of Public Health Sciences, and the Alberta Centre for Injury Control and Research, School of Public Health, University of Alberta
  • Hurwitz EL – Department of Public Health Sciences, John A. Burns School of Medicine, University of Hawaii at Manoa
  • Cassidy JD – Centre of Research Expertise in Improved Disability Outcomes (CREIDO), University Health Network Rehabilitation Solutions, Toronto Western Hospital, Departments of Public Health Sciences and Health Policy, Management and Evaluation, University of Toronto, Division of Health Care and Outcomes Research, Toronto Western Research Institute
  • Peloso PM – Endocrinology, Analgesia and Inflammation, Merck & Co
  • Cote P – Centre of Research Expertise in Improved Disability Outcomes (CREIDO), University Health Network Rehabilitation Solutions, Toronto Western Hospital, Departments of Public Health Sciences and Health Policy, Management and Evaluation, University of Toronto, Division of Health Care and Outcomes Research, Toronto Western Research Institute, Institute for Work and Health
  • Haldeman S – Department of Neurology, University of California Irvine, Department of Epidemiology, School of Public Health, University of California Los Angeles

Publication Information:

  1. Spine 2008; 33(4S): S14-S23.
  2. Spine 2008; 33(4S): S33-S38.
  3. Spine 2008; 33(4S): S214-S220.
  4. Spine 2008; 33(4S): S199-S213.

Summary:

This review will be unique in that four papers will be examined simultaneously. It is understood that some of these papers will be of minimal interest to the average clinician. However, by amalgamating four papers together this review will hopefully provide a brief overview of each so that readers can understand the basis for this Neck Pain Task Force project.

1) A NEW CONCEPTUAL MODEL OF NECK PAIN: LINKING ONSET, COURSE, AND CARE

It is important to first understand the model from which the Neck Pain Task Force (NPTF) operated. The NPTF mainly considered nonspecific or mechanical neck pain. The overarching purpose was to provide an integrated model to link the epidemiology of neck pain with management. They formulated several premisesfor their model:
  1. The primary perspective of interest is that of people with neck pain or who are at risk of developing neck pain.
  2. The course of neck pain is best described as episodes occurring over a lifetime with variable degrees of recovery between episodes.
  3. The onset and course of neck pain are multifactorial.
  4. The management and subsequent course of neck pain depend on the options available at the time and how these options are appraised.
  5. The impact of neck pain on the person can be described within various domains.
  6. Linkages between factors and impacts can occur in multiple directions.
The conceptual model includes five components:
  1. Factors affecting the onset and course of neck pain – these include risk and prognostic factors – can be modifiable or non-modifiable.
  2. The “care” complex – most people with neck pain do not seek care, the decision to seek care is influenced by environmental and personal factors including health policy factors. Options include no care, self care, and professional care. This component includes the clinical encounter and doctor/therapist-patient relationship.
  3. The “participation” complex – those with neck pain need to determine whether their pain affects their ability to participate in different activities including work, recreation, activities of daily living, etc. They can continue as usual, modify their activity levels or not participate.
  4. The “claim” complex – this generally applies if there is insurance to pay for claims. There is tremendous variation in the amount and availability of insurance from region to region.
  5. The impact and outcomes of neck pain – this was described as occurring in 5 domains that can occur over shot and long term timeframes:
    1. Impact on body structures and functions
    2. Impact on the person’s ability to accomplish tasks
    3. Impact on the person’s involvement in life situations
    4. Impact on the person’s wellbeing
    5. Impact on resource utilization
The NPTF proposed a new classification of neck pain and its associated disorders, appearing as a grading system based on pain severity, similar to that of the Quebec Task Force. In the NPTF grading scheme there are 4 grades where:
  • 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.
This system is meant to encompass all types of neck pain, including those from motor vehicle accidents (whiplash associated disorders). The NPTF recommends that Grade I neck pain is eligible for primary health care or car repair only, grade II is eligible for reimbursement of secondary/tertiary care or temporary wage replacement, grade III is eligible for long-term disability, and grade IV is eligible for permanent disability or punitive damages for pain and suffering.

2) METHODS FOR THE BEST EVIDENCE SYNTHESIS

The NPTF conducted a literature search between 1980 and 2006 on Medline using a variety of suitable search terms in English, French, and Swedish. They crafted a suitable set of inclusion and exclusion criteria and applied them to all identified studies to identify relevant studies.

All relevant studies found in the literature search were critically reviewed by members of the NPTF Scientific Secretariat for study quality, particularly for internal validity, sources of bias, and clinical relevance. Information of interest from scientifically admissible studies was put into the suitable evidence tables constructed specifically for different important areas to aid with best evidence synthesis. These areas included:
  • incidence and risk factors, prevalence, prevention
  • assessment and diagnosis
  • interventions
  • costs and health care utilization
  • natural history/course and prognostic factors
The evidence accumulated in these evidence tables allowed the NPTF members to outline the best evidence, identify inconsistencies in the evidence, and form their summary statements.

31,878 citations were identified in the literature. After applying the inclusion/exclusion criteria only 1203 studies were deemed relevant to the NPTF mandate and reviewed. 552 (46%) were accepted as admissible and comprised the best evidence synthesis. The breakdown of these accepted studies is as follows:
  • Epidemiology: 249 studies
  • Assessment and diagnosis: 95 studies
  • Course/prognosis: 70 studies
  • Interventions: 170 studies
  • Economic costs: 13 studies
3) RESEARCH PRIORITIES AND METHODOLOGICAL IMPLICATIONS

The NPTF noted the variable quality of the literature on neck pain. Some areas had higher quality evidence than others. For example 47% of the studies on interventions were admissible, compared with 35% of the studies on diagnosis and assessment, 31% for course and prognostic factors, 93% for economic costs, and 53% of the epidemiological studies. Certainly those areas with lower quality evidence warrant more study.

There appears to be a need for more and better studies on treatments for neck pain. Studies of interventions need to ideally use research design that are stronger than the case series, as the NPTF point out that this method cannot determine effectiveness or efficacy. Even RCTs were noted to frequently have methodological issues including:
  • inadequate sample sizes
  • failure to consider clinical importance of findings
  • inadequate reporting of baseline characteristics
  • inadequate or inappropriate statistical analyses
  • high drop out or crossover rates
The NPTF concluded that more conceptually sound and theory driven research is required. They advocate using innovative study designs and analysis including qualitative methods, decision analysis methods, and structural equation modeling.

4) CLINICAL PRACTICE IMPLICATIONS

When assessing a patient with neck pain the NPTF suggests that clinicians consider the following:
  • Neck pain is common; most people with neck pain do not seek care. Neck pain and the resulting disability are usually multi-factorial in nature.
  • Decisions to seek care depend on a variety of local and personal circumstances.
  • A descriptive clinical diagnosis may be better than providing a tissue diagnosis as the source of pain. The NPTF repeatedly recommend the Grade I-IV schemes described above.
  • It is useful to use self-report questionnaires to assess pain severity and the amount of interference with daily activities (using a Visual Analog Scale or the Neck Disability Index respectively).
  • Clinicians should be aware that a serious disease or pathology could cause neck pain and thus evaluate patients for potential red flags.
  • Inspection, ranges of motion, palpation for tenderness, a neurological examination (reflexes, muscle strength, and sensory deficits), and provocation testing (especially contralateral rotation of the head with extension or the arm and fingers) should be considered in the physical examination when seeing a patient with neck pain.
  • There is no evidence to support the use of electrodiagnostic testing in patients with neck pain without suspected radiculopathy (i.e. not necessary for grade I or II neck pain).
  • Regular 3-view x-rays (AP, APOM, lateral) are as accurate as flexion-extension series or 5-view x-rays in identifying fracture following a motor vehicle accident.
  • There is no evidence that the degree of cervical curvature on x-ray can identify WAD or cervical muscle spasm.
  • Diagnostic testing is not indicated in grade I or II neck pain.
  • Degenerative changes in the neck seen on x-ray are usually unrelated to neck pain.
When managing patients with neck pain after a motor vehicle accident it is important for clinicians to consider the following:
  • It is helpful to reassure patients about the absence of pathology in grade I or II neck pain and that they are unlikely to develop spinal instability, neurological injury, or severe ongoing disability.
  • It is important to promote timely return to usual activities.
  • For short term relief exercise training and mobilizations are likely helpful for neck pain after a motor vehicle accident.
For neck pain without trauma:
  • There is no clear choice in treatment where one modality is superior to the rest, thus patient preference should be considered when deciding on a course of treatment for relief of neck pain.
  • Exercise training, mobilization, manipulation, low-level laser, acupuncture, and analgesics are likely helpful in providing short term relief.
Treatment side effects of note:
  • In patients under 45 years there is an association between chiropractic care and vertebrobasilar artery (VBA) stroke, however there is a similar association between family physician care and VBA stroke. There is NO increased risk of VBA stroke after chiropractic care. Such associations are likely due to patients with headache and neck pain from vertebral artery dissection seeking care while in the early stage of a VBA stroke. Such strokes are very rare.
Other points of interest:
  • Ergonomic interventions and car re-design have not been proven to prevent neck pain.
  • Several complementary and alternative medicine treatments have more evidence of efficacy than conventional medical care. Major complications of common treatments are exceedingly rare and likely equivalent in frequency across treatments.
  • When it comes to treatment plans, less is more – multiple visits and treatments may make the neck pain and disability worse.
  • It is imperative to help patients re-gain control over their neck pain and give them options for self-management.

Conclusions & Practical Application:

This review presents the findings of four articles contributed by the Neck Pain Task Force. The work conducted by this group is extremely important and should carry a tremendous amount of weight based on its quality and detail and the importance and quality of the researchers who did it. The findings are only about one month old at the time of posting this review, so it is difficult to determine or estimate their effect.

There are bound to be criticisms of the methods and findings of the NPTF as there is of any major review and synthesis of the literature that provides recommendations that could alter how practice is conducted by clinicians. Thus there will likely be some debate in the coming months, which will spur on future research. It is imperative for any clinician who treats patients with neck pain to familiarize themselves with the findings of the NPTF as part of being an evidence based practitioner.

It is hoped that this review will begin this process for RRS subscribers. Subsequent, more detailed reviews on the assessment and treatment of neck pain based on the NPTF findings will follow in the next few months.

It is quite possible (and in my estimation likely) that five years from now clinicians, insurers, and policy makers will speak of the NPTF findings with the same familiarity and acceptance that they do of the Quebec Task Force (QTF) report currently. It is also possible (and likely) that the NPTF findings will largely replace those of the QTF particularly in how motor vehicle accidents and their claims are managed. The NPTF findings have the obvious advantage over the QTF findings in that they address both MVA and non-MVA related neck pain.

Despite the importance of the NPTF documents and the quality of the group conducting the research and their findings, it should not be assumed that it is a perfect collection of work. From a methodological point of view, there were some significant drawbacks that could be argued to affect the validity of the findings. One of these was that only one electronic database (Medline) was searched. The NPTF argued that Medline should capture between 90 and 95% of the articles on a topic and that should be sufficient. That still means that at least 5 to 10% (or 1 in 10 to 1 in 20 articles) of the relevant articles in the literature were potentially missed.

Numerous other databases of interest could have been searched including Embase, CINAHL, The Index to Chiropractic Literature, Mantis, and AltMed, among others. The NPTF argued that they could not use more databases due to practical reasons. Also due to practical reasons the NPTF only conducted their searches in 3 languages (English, French, and Swedish). This again limits the true amount of the literature that they could access. However as they correctly point out, increasingly most academic papers are being published in English only.

Another potential source of bias that could be identified from the NPTF methods is that reviewers were not blinded to the authors or date of publication of the articles they reviewed. The NPTF also chose not to give articles a numerical score; they only judged articles under review as being admissible or not admissible with some debate over article inclusion allowed.

Such debate allows for stronger personalities within a group of others to be persuasive, particularly if they are passionate about including/excluding a certain article. If article scoring was used and a cutoff score established to determine admissibility that could reduce some possible methodological bias.

From a clinical standpoint one thing that is somewhat frustrating is that the NPTF espouses the use of paper-based outcome measures such as the Neck Disability Index (NDI) and visual analog scale (VAS) and they differentiate between grade I and grade II neck pain by the amount of interference that they provide with daily activities.

However they do not produce any means of objectively determining between grade I and grade II neck pain (for example if a certain cutoff number on the NDI could be used to help differentiate between the two), it will have to be a subjective judgment on the part of the clinician. Hopefully some instruction or direction in this area can be provided in further discourse.

It will be interesting in the coming months and years to see the amount of buy-in to the findings and recommendations of the NPTF. One issue of particular interest will be seeing whether different professions, policy makers, and insurers are willing to get away from tissue-specific diagnoses (for example sprain/strain, myofascial pain syndromes, facet syndromes, etc) and go to the grade I to IV scheme recommended by the NPTF. As we have previously seen with the Quebec Task Force and the adoption of the WAD scheme, one would imagine this to be quite likely.