Are perioperative interventions effective in preventing chronic pain after primary total knee replacement? A systematic review

Objectives
For many people with advanced osteoarthritis, total knee replacement (TKR) is an effective treatment for relieving pain and improving function. Features of peri-operative care may be associated with the adverse event of chronic pain six months or longer after surgery; effects may be direct, e.g. through nerve damage or surgical complications, or indirect through adverse events. This systematic review aims to evaluate whether non-surgical peri-operative interventions prevent long-term pain after TKR.
Methods
We conducted a systematic review of peri-operative interventions for adults with osteoarthritis receiving primary TKR evaluated in a randomised controlled trial (RCT). We searched The Cochrane Library, MEDLINE, Embase, PsycINFO and CINAHL to February 2018. After screening, two reviewers evaluated articles. Studies at low risk of bias according to the Cochrane tool were included.
Interventions
Peri-operative non-surgical interventions; control receiving no intervention or alternative treatment.
Primary and secondary outcome measures
Pain or score with pain component assessed at six months or longer post-operative.
Results
44 RCTs at low risk of bias assessed long-term pain. Intervention heterogeneity precluded meta-analysis and definitive statements on effectiveness. Good-quality research provided generally weak evidence for small reductions in long-term pain with local infiltration analgesia (3 studies), ketamine infusion (1 study), pregabalin (1 study) and supported early discharge (1 study) compared with no intervention. For electric muscle stimulation (2 studies), anabolic steroids (1 study) and walking training (1 study) there was a suggestion of more clinically important benefit. No concerns relating to long-term adverse events were reported. For a range of treatments there was no evidence linking them with unfavourable pain outcomes.
Conclusions
To prevent chronic pain after TKR, several peri-operative interventions show benefits and merit further research. Good quality studies assessing long-term pain after peri-operative interventions are feasible and necessary to ensure that patients with osteoarthritis achieve good long-term outcomes after TKR.