Relationship Between Intraarticular Injections on Patient-reported Outcomes in Total Knee Arthroplasty

Total knee arthroplasty (TKA) patients undergo intraarticular (IA) injections before surgery to reduce pain, improve function, and delay surgery. The purpose of this study was to determine the relationship between different types of IA injection exposure and preoperative and postoperative outcomes.

We reviewed a series of 321 patients who underwent primary TKA from 2016 to 2022, excluding patients with contralateral TKA within 6 months. Patients were categorized by IA injection type-ketorolac, triamcinolone, or no injection-received within 6 months of TKA. Main outcomes were the Knee Injury and Osteoarthritis Outcome Score (KOOS), and opioid prescriptions received before and 3 months after TKA.

Most of the 321 patients were female (64%) and White (62%). Of the 321 patients who underwent TKA, 113 (35%) received ketorolac, 64 (20%) received triamcinolone, and 144 (45%) received no injections. Significant differences in preoperative KOOS pain and ADL scores (P = 0.021 and P = 0.047) were observed among groups. Triamcinolone was associated with significantly less preoperative pain (P = 0.016) and greater function (P = 0.046) than ketorolac. No significant differences were found between groups in any KOOS subscale at 3 months post-TKA. Opioid prescriptions, refills, and total morphine milligram equivalents did not differ between injection groups.

Triamcinolone IA injections were associated with less pain and greater function before TKA than ketorolac. Future studies should include prospective studies, stratified by severity of knee osteoarthritis, to investigate whether exposure to IA injections has a favorable risk-benefit profile, accounting for osteoarthritis disease progression and heterogeneity.