Postoperative pain relief after total knee arthroplasty: A Bayesian network meta-analysis and systematic review of analgesic strategies based on nerve blocks.

STUDY OBJECTIVE: A Bayesian network meta-analysis was performed to compare the analgesic efficacy of the following nerve block techniques: femoral nerve block (FNB), adductor canal block (ACB), infiltration between the popliteal artery and the capsule of the posterior knee (iPACK), and genicular nerve block (GNB) following total knee arthroplasty (TKA).

DESIGN: Systematic review and network meta-analysis (NMA).

PATIENTS AND MEASUREMENTS: We searched the Web of Science, PubMed, EMBASE, and Cochrane Library databases until September 20, 2022. Patients who were treated by any of the above four nerve block techniques (alone or in combination) after TKA were included. Patients who underwent minimally invasive knee surgery were excluded. The indicators included pain scores during rest and mobilization, opioid consumption after surgery, postsurgical mobilization function (ROM [range of motion], TUG [Timed-Up-and-Go] test) at 24 h and 48 h, and length of hospital stay. The risk of bias was assessed by the Cochrane risk of bias tool.

RESULTS: Forty-two studies involving 2857 patients were eligible for this study. This NMA suggested that ACB + iPACK was the most efficacious option for improving ambulation ability and shortening the length of hospital stay. Furthermore, ACB + iPACK was the best regimen for resting-pain and movement-pain relief (78% and 87%, respectively) and for reducing opioid consumption (90%) at 48 h. However, FNB + iPACK was the most efficacious option for relief of resting pain (42%) and reducing opioid consumption (68%) at 24 h; GNB was the most efficacious option for movement pain relief at 24 h (94%).

CONCLUSION: Considering both pain control and knee functional recovery, ACB + iPACK may be the optimal analgesic regimen for patients after TKA. At the same time, it significantly reduces pain and opioid consumption at 48 h. However, ACB + iPACK is not the recommended technique for short-term (24 h) pain control.

CLINICAL TRIAL REGISTRATION: PROSPERO (CRD42022362322).