Acute postoperative pain at rest after hip and knee arthroplasty: severity, sensory qualities and impact on sleep.

Background: The management of acute postoperative pain poses a significant challenge in surgical specialities. Despite the prevalence and impact of acute postoperative pain, there is a paucity of published data regarding its occurrence and sensory qualities after joint replacement.

Objective: That a proportion of patients would experience severe acute postoperative pain at rest after total hip replacement (THR) and total knee replacement (TKR).

Methods: Pain was assessed preoperatively, and then five times daily for the first three postoperative days in 105 THR and TKR patients. Pain severity was assessed using a pain Visual Analogue Scale and the sensory qualities of pain were assessed using the pain descriptors from the Short-Form McGill Pain Questionnaire.

Results: Median acute pain scores peaked on the first postoperative day, with 58% of TKR patients and 47% of THR patients reporting moderate-severe pain. Preoperative pain was most frequently described as aching, stabbing and sharp, whereas acute postoperative pain was described as aching, heavy and tender. Night pain disturbed between 44-57% of TKR patients and 21-52% of THR patients on postoperative nights 1-3.

Conclusions: These findings demonstrate that acute postoperative pain at rest after joint replacement, particularly TKR, is poorly managed, although it does not reach the severity of preoperative pain. Methods: Level IV (observational cohort study).