Preoperative Pain Catastrophizing and Neuropathic Pain Do Not Predict Length of Stay and Early Post-Operative Complications following Total Joint Arthroplasty.

Background: Both pain catastrophizing and neuropathic pain have been suggested as prospective risk factors for poor postoperative pain outcomes in total joint arthroplasty (TJA).

Objective: We hypothesized that pain catastrophizers, as well as patients with pain characterized as neuropathic, would exhibit higher pain scores, higher early complication rates and longer lengths of stay following primary TJA.

Methods: A prospective, observational study in a single academic institution included 100 patients with end-stage hip or knee osteoarthritis scheduled for TJA. In pre-surgery, measures of health status, socio-demographics, opioid use, neuropathic pain (PainDETECT), pain catastrophizing (PCS), pain at rest and pain during activity (WOMAC pain items) were collected. The primary outcome measure was the length of stay (LOS) and secondary measures were the discharge destinations, early postoperative complications, readmissions, visual analog scale (VAS) levels and distances walked during the hospital stay.

Results: The prevalence of pain catastrophizing (PCS ≥ 30) and neuropathic pain (PainDETECT ≥ 19) was 45% and 20.4%, respectively. Preoperative PCS correlated positively with PainDETECT (rs = 0.501, = 0.001). The WOMAC positively correlated more strongly with PCS (rs = 0.512 = 0.01) than with PainDETECT (rs = 0.329 = 0.038). Neither PCS nor PainDETECT correlated with the LOS. Using multivariate regression analysis, a history of chronic pain medication use was found to predict early postoperative complications (OR 38.1, = 0.47, CI 1.047-1386.1). There were no differences in the remaining secondary outcomes.

Conclusions: Both PCS and PainDETECT were found to be poor predictors of postoperative pain, LOS and other immediate postoperative outcomes following TJA.