Changes in problem-solving style when pain does not resolve. A longitudinal analysis of adults with chronic pain after total knee replacement.

One-fifth of adults who receive a total knee replacement (TKR) go on to develop chronic pain. The behavioural approach taken to find a solution to pain may vary from assimilative (pursuit of analgesia) to accommodative (acceptance of pain insolubility and adoption of alternative goals). A total of 313 patients participated in a trial of an enhanced care pathway for TKR reported pain at 3 months after surgery. Participants undertook treatment as usual or treatment as usual with a new optimised support and treatment after replacement care pathway. Several pain and psychosocial outcomes (including problem-solving) were assessed. Two of the 3 problem-solving subscales moved from assimilative to accommodative over time (solving pain, acceptance of insolubility) and the overall belief in a solution decreased. Despite this shift to a more accommodative (accepting) problem-solving approach, participants reported lower meaningfulness of life over time. This reduced meaningfulness of life was associated with an increase in pain severity, interference, and reduced knee function. These interactions were not moderated by the treatment pathway to which participants were allocated. Overall, these results suggest that while patients who have pain after TKR become less determined to pursue analgesic solutions, this accommodation is not a naturally occurring positive acceptance. We discuss the possible reasons for this lack of functional and adaptive accommodation to chronic pain over the 12 months postoperative period.