This systematic review appraises the evidence from human clinical trials comparing post-operative pain scores and opioid consumption in patients receiving intra-articular (IA) ketamine versus other modalities of analgesia after orthopedic joint procedures.
Studies were identified from Embase, Scopus, PubMed and OVID Medline databases. Included studies compared patients receiving IA ketamine versus other modalities of analgesia. The primary outcome of interest was post-procedural pain score and total opioid consumption, while secondary outcomes included time to rescue analgesic medication request, active range of motion, time to mobilization and adverse effects.
Seventeen studies were included. Dosage of ketamine varied widely from 0.25 mg/kg to 2 mg/kg. Fifteen of seventeen demonstrated decreased overall pain scores and decreased total post-operative opioid consumption in patients receiving intra-articular ketamine versus control groups. Included studies generally demonstrated reduced time to mobilization and increased latency until rescue analgesic medication in the intra-articular ketamine group.
Patients who received IA ketamine generally reported lower pain scores and had lower post-operative opioid consumption after orthopedic joint procedures. This suggests that the IA route of ketamine delivery may be a useful analgesic modality, although future larger-scale trials should explore its pharmacokinetics, optimal dosing, safety and cost-effectiveness.