Neck Pain Clinical Prediction Rule to Prescribe Combined Aerobic and Neck-Specific Exercises: Secondary Analysis of a Randomized Controlled Trial

Objective A previous randomized controlled trial revealed that combined aerobic and neck-specific exercises yielded greater improvement than neck-specific exercises alone after a 6-month intervention in outpatients with nonspecific neck pain (NP). The aim of this secondary analysis was to identify subgroups of patients in the combined exercises group most likely to benefit from the intervention. Methods Sixty-nine patients were included. The original trial was conducted in multiple physical therapy outpatient clinics twice a week for 6 weeks; follow-up was 6 months after assignment. The primary outcome was the therapeutic success rate (Global Rating of Change Score >= +5, "quite a bit better") after 6 weeks of training and at the 6-month follow-up. Candidate predictors from patients' medical history and physical examination were selected for univariable regression analysis to determine their association with treatment response status. Multivariable logistic regression analysis was used to derive preliminary clinical prediction rules. Results The clinical prediction rule contained 3 predictor variables: (1) symptom duration <= 6 months, (2) neck flexor endurance >= 18 seconds, and (3) absence of referred pain (Nagelkerke R-2 = .40 and -2 log likelihood = 60.30). The pre-test probability of success was 61.0% in the short term and 77.0% in the long term. The post-test probability of success for patients with at least 2 of the 3 predictor variables was 84.0% in the short term and 87.0% in the long term; such patients will likely benefit from this program. Conclusion A simple 3-item assessment, derived from easily obtainable baseline data, can identify patients with NP who may respond best to combined aerobic and neck-specific exercises. Validation is required before clinical recommendation. Impact Patients experiencing NP symptoms <= 6 months who have no referred pain and exhibit neck flexor endurance >= 18 seconds may benefit from a simple self-training program of combined aerobic and neck-specific exercises.