Objective: To investigate outcome and prognostic determinants for arm pain presenting to primary care and physiotherapy services.
Methods: Patients with arm pain were recruited as they presented to primary care and physiotherapy services, and were followed for 12 months. At baseline, they were classified by diagnosis using a validated examination schedule. Depression, somatizing tendency, health anxiety, fear-avoidance beliefs and chronic pain outside the arm were ascertained using standard definitions. Three outcomes were considered: same-site pain during the final month of follow-up (continuing pain); pain present on most days of that month; and pain present without a break of 7 days over follow-up ('unremitting' pain). Associations were explored in multi-level logistic regression models and summarized as odds ratios (ORs) with 95% confidence intervals (95% CIs).
Results: Altogether, 313 (83%) of 375 subjects completed follow-up, including 53% with 'continuing' and 24% with 'unremitting' pain. 'Continuing' pain was predicted most strongly by male sex (OR 1.9, 95% CI 1.2-3.2) (this association was restricted largely to the elbow), higher frequency of pain in the past month at baseline (OR 2.5, 95% CI 1.1-5.6), chronic pain at sites outside the arm (ORs 1.6-2.4 for different sites) and current smoking (OR 3.3, 95% CI 1.6-6.6). There were also indications that mental health and fear-avoidance beliefs influenced prognosis. Predictors for the other two adverse outcomes were similar.
Conclusion: Arm pain often persists in patients who consult medical services. Predictors of persistence include male sex (elbow only), frequency of pain at baseline, chronic pain at other sites and smoking.