Effectiveness of postdischarge intervention for reducing the severity of chronic pain after total knee replacement: systematic review of randomised controlled trials

Objective
Approximately 20% of patients experience chronic pain after total knee replacement (TKR). The aim of this systematic review was to evaluate the effectiveness of post-discharge interventions commenced in the first three months after surgery in reducing the severity of chronic pain after TKR.

Design
The protocol for this systematic review was registered on PROSPERO (CRD42017041382). MEDLINE, Embase, CINAHL, PsycINFO and The Cochrane Library were searched from inception to November 2016. Randomised controlled trials of post-discharge intervention which commenced in the first three months after TKR surgery were included. The primary outcome of the review was self-report pain severity at 12 months or longer after TKR. Risk of bias was assessed using the Cochrane risk-of-bias tool.

Results
Seventeen trials with data from 2,485 randomised participants were included. The majority of trials evaluated physiotherapy interventions (n=13); other interventions included nurse-led interventions (n=2), neuromuscular electrical stimulation (n=1) and a multidisciplinary intervention (n=1). Opportunities for meta-analysis were limited by heterogeneity. No study found a difference in long-term pain severity between trial arms, with the exception of one trial which found home-based functional exercises aimed at managing kinesiophobia resulted in lower pain severity scores at 12 months post-operative compared to advice to stay active.

Conclusion
This systematic review and narrative synthesis found no evidence that one type of physiotherapy intervention is more effective than another at reducing the severity of chronic pain after TKR. Further research is needed to evaluate non-physiotherapy interventions, including the provision of care as part of a stratified and multidisciplinary care package.