Justification for chiropractic care to prevent recurrence of neck pain remains elusive

Martel J, Dugas C, Dubois JD, Descarreaux M. A randomised controlled trial of preventive spinal manipulation with and without a home exercise program for patients with chronic neck pain. BMC Musculoskelet Disord 2011; 12: 41.

Aim

‘to investigate the efficacy of preventive spinal manipulation therapy (SMT) compared to a no treatment group in NCNP [non-specific chronic neck pain] patients’ and ‘to assess the efficacy of SMT with and without a home exercise program.’

Design

Non-blinded, RCT with three parallel arms.

Setting

Chiropractic clinic and human research laboratory, Department of Chiropractic, Université du Québec à Trois-Rivières, Canada.

Participants

Ninety-eight adults with NCNP, aged between 18 and 60 years, with neck pain lasting 12 weeks or more, who had not received physical therapy, were not currently under chiropractic care or rehabilitation for the neck area and were willing to adhere to the treatment protocol, were assigned to treatment. Excluded were persons with neck pain due to a motor vehicle accident, neck surgery, severe osteoarthritis and inflammatory arthritis, neurological, cardiovascular, infectious metabolic and endocrine diseases, pregnancy and any cardinal signs of potential vertebral artery dissection.

Interventions

All participants received a short course of SMT (i.e. 10–15 sessions of symptomatic treatment over a 5–6 week period) prior to commencing chiropractic preventive care (CPC), which lasted 10 months. The three arms of CPC were: (i) SMT consisting of a maximum of four manipulations to the cervical or upper thoracic areas, once a month, lasting 10–15 min in duration; (ii) SMT (as previously described) plus home exercise programme (at least three times per week) with initial training and ongoing counselling, which included warm-up, cool-down, four stretching/mobilisation exercises, and four concentric and isometric strengthening exercises; and (iii) no SMT or home exercise (attention-control), by which participants attended the clinic every 2 months, for 20–30 min, to undergo the same assessments as the other two groups but at a slower pace.

Main outcome measures

The primary outcome measure was a 10-cm VAS for pain. Attainment of a level of clinically acceptable pain was defined as maintaining up to follow-up at least two points less than baseline on the VAS. Secondary outcome measures were cervical spine function, as assessed with the cervical range of motion instrument (cROM), and disability, as measured using the Neck Pain Disability Index (NDI) and the Bournemouth Questionnaire (BQ). Exploratory outcome measures included health-related QoL (HRQoL, using the SF-12 questionnaire), fear and avoidance phenomena (using the Fear-avoidance Behaviour Questionnaire) and exercise adherence and co-intervention (using a weekly diary). Data were collected prior to symptomatic treatment, prior to CPC, and every 2 months during the 10-month preventive care period.

Main results

There were no significant between-group differences in the primary, secondary and exploratory outcomes during the 10-month CPC. Most patients in each group stayed below a level of clinically acceptable pain with preventive care. The attention-control group required significantly more co-intervention than the other groups and also chose to apply ice more often. However, significant between-group differences were not found for HRQoL.

Authors' conclusion

‘there is no additional benefit for patients with NCNP to receive monthly preventive SMT or monthly preventive SMT with a home exercise program compared to meeting a chiropractor once every 2 months to discuss neck problems. In view of the rare but possible adverse reactions to cervical SMT, this tends to reject CPC when SMT is the main intervention. However, the premise of CPC stating that regular treatments, designed to preserve optimum health, will also minimize the recurrence of clinical problems, might hold true when intervention is geared towards reassurance, patient education, help with self-management and active care strategies. Further research in this domain has to be conducted.’

Address

M Descarreaux, Département de chiropratique, Université du Québec à Trois-Rivières, Trois-Rivières, Canada G9A 5H7.

E-mail: [e-mail]

Commentary

Lack of blinding was identified as a study limitation. However, this limitation would be expected to bias findings away from the null hypothesis, which in this study was not rejected based on the main analysis.

Although the authors indicated that the main analysis was undertaken on an ITT basis, they also indicated that the pre-established statistical power was not reached because of between-group differences in number of dropouts. This discussion of dropouts is consistent with per-protocol analysis, not intention-to-treat analysis, which refers to analysing outcomes for the initially intended recipients of treatment, not the actual recipients of treatment. It is not clear how the main analysis can be characterised as based on ITT, but the authors are clear in noting that their hypotheses of preventive effects from SMT and the combined SMT-exercise intervention were not supported.

The authors speculated that non-specific effects arising from the patient, provider and patient–provider interaction accounted for stabilisation of improvement in the attention-control group. Considering that the study did not include a control group receiving no prevention-oriented service (e.g. a waiting-list control group), the conclusion about value in taking charge and managing a patient to prevent recurrence of neck pain is presumptuous. It is not clear that stabilisation of improvement following treatment requires at least minimal chiropractic management.

Based on expressed concerns about efficacy and cost-effectiveness of preventive care, the authors called for more research, including possibly a RCT. Raising the issue of cost-effectiveness may be premature since the authors did not establish that any kind of chiropractic care, including what the authors described as care ‘geared towards reassurance, patient education, help with self-management and active care strategies’ to prevent neck pain and ‘preserve optimum health’ is demonstrably better than providing no service at all. The authors declared that ‘Further research in this domain has to be conducted’ although, it is not clear that this is warranted, especially considering the lack of differences in outcomes found between the three intervention groups.

Conflict of interest None declared.

Authors' reply

The authors did not wish to reply.