Strong evidence supports that the use of peri-articular local anesthetic infiltration in total knee arthroplasty (TKA) decreases pain and opioid use compared to placebo.

Rationale
Five high quality studies (Nakai 2013, Koh 2011, Klasen 1999, Busch 2006, Chen 2012) compared peri-articular infiltration (PAI) to placebo (normal saline or no infiltration) for total knee arthroplasty. Improved function (Chen 2012), lower opioid consumption Busch 2006, Chen 2012, improved patient satisfaction (Busch 2006), and lower visual analog scale (VAS) pain scores (Nakai 2013, Koh 2011, Busch 2006, Chen 2012) all favored peri-articular injection.
 
Twenty-seven high quality studies originally met the selection criteria. Comparisons between PAI and placebo, PAI and peripheral nerve blocks (femoral and/or sciatic nerve blocks), and PAI and epidural blocks were attempted. However, due to the heterogeneity of the studies, PAI could only be compared to placebo. The heterogeneity of the studies included differences in infiltration solution (long-acting local anesthetics, plus or minus ketorolac, plus or minus opioid, plus or minus corticosteroid), varying concentrations of infiltration solution and injections, single-injection or catheter peripheral nerve blocks, peripheral nerve blocks (femoral and/or sciatic), and epidural catheter infusions (local anesthetic, opioid, and rates). 
 
  1. Busch,C.A., Shore,B.J., Bhandari,R., Ganapathy,S., MacDonald,S.J., Bourne,R.B., Rorabeck,C.H., McCalden,R.W. Efficacy of periarticular multimodal drug injection in total knee arthroplasty. A randomized trial. J Bone Joint Surg Am 2006/5; 5: 959-963
  2. Chen,Y., Zhang,Y., Zhu,Y.L., Fu,P.L. Efficacy and safety of an intra-operative intra-articular magnesium/ropivacaine injection for pain control following total knee arthroplasty. J Int.Med Res. 2012; 5: 2032-2040
  3. Klasen,J.A., Opitz,S.A., Melzer,C., Thiel,A., Hempelmann,G. Intraarticular, epidural, and intravenous analgesia after total knee arthroplasty. Acta Anaesthesiol.Scand. 1999/11; 10: 1021-1026
  4. Koh,I.J., Kang,Y.G., Chang,C.B., Do,S.-H., Seong,S.C., Kim,T.K. Does periarticular injection have additional pain relieving effects during contemporary multimodal pain control protocols for TKA?: A randomised, controlled study. Knee 2011; 0: -
  5. Nakai,T., Tamaki,M., Nakamura,T., Nakai,T., Onishi,A., Hashimoto,K. Controlling pain after total knee arthroplasty using a multimodal protocol with local periarticular injections. J Orthop 2013; 2: 92-94