Pain with neuropathic characteristics after surgically treated lower limb fractures: Cost analysis and pain medication use.

Introduction: Neuropathic pain is prevalent among people after lower limb fracture surgery and is associated with lower health-related quality of life and greater disability. This study estimates the financial cost and pain medication use associated with neuropathic pain in this group.

Methods: A secondary analysis using pain data collected over six postoperative months from participants randomised in the Wound Healing in Surgery for Trauma (WHiST) trial. Pain states were classified as pain-free, chronic non-neuropathic pain (NNP) or chronic neuropathic pain (NP). Cost associated with each pain state from a UK National Health Service (NHS) and personal social services (PSS) perspective were estimated by multivariate models based on multiple imputed data. Pain medication usage was analysed by pain state.

Results: A total of 934 participants who provided either 3- or 6-months pain data were included. Compared to participants with NP, those with NNP (adjusted mean difference -£730, p = 0.38, 95% CI -2368 to 908) or were pain-free (adjusted mean difference -£716, p = 0.53, 95% CI -2929 to 1497) had lower costs from the NHS and PSS perspective in the first three postoperative months. Over the first three postoperative months, almost a third of participants with NP were prescribed opioids and 8% were prescribed NP medications. Similar trends were observed by 6 months postoperatively.

Conclusion: This study found healthcare costs were higher amongst those with chronic NP compared to those who were pain-free or had chronic NNP. Opioids, rather than neuropathic pain medications, were commonly prescribed for NP over the first six postoperative months, contrary to clinical guidelines.