A prospective investigation of the prevalence of persistent pain following traumatic injury

Allyson Browne^1,2, Stephan Schug^2,3, Sudhakar Rao¹

¹Trauma Services, Royal Perth Hospital, Western Australia
²School of Medicine and Pharmacology, University of Western Australia
³Pain Medicine, Royal Perth Hospital, Western Australia

Background: A high incidence of persistent pain and disability following elective trauma surgery is often reported (e.g., Gehling, et al., 1999).  In 2005, Royal Perth Hospital trauma registry data revealed that nearly 40% of patients experience persistent pain and less than 40% return to work within 12 months post injury. Yet little is known about which acute factors place trauma patients at risk of ongoing disability.  This project aims to determine the prevalence of persistent pain following traumatic injury, and identify a set of acute physical and psychological risk factors that predict pain outcomes.

Method: One hundred and sixty five non head injured trauma inpatients (23% female, Injury Severity Score M = 10.15, M age = 36 years) completed standardised pain and post trauma assessments within a week post injury.  Pain and psychological function were reassessed at three months post injury using standardized questionnaires.

Results: Of the 38 patients who have completed the three month questionnaires so far, 84% have reported ongoing pain. Moreover, 29% and 8% have reported clinically significant depressive and post traumatic stress symptoms respectively.  Not surprisingly, significant positive correlations exist between reported pain-related interference and depressive symptom severity (p< 0.05), and between pain intensity ratings and post traumatic stress ratings (p<0.05) at follow-up after controlling for age, gender, and injury severity.  Investigations of the extent to which acute pain and psychological function predict pain outcomes are ongoing.

Conclusions: These preliminary findings suggest a high incidence of persistent pain during the early recovery phase following a traumatic injury.  Ongoing investigation of factors that can identify those patients most at risk of persistent pain is warranted with a view to providing earlier targeted intervention.

References: Gehling M, Scheidt C-E, Niebergall H, Kacaoglu E, Tryba M, Geiger K. Persistent pain after elective trauma surgery. Acute Pain 1999;2(3):110-114.