Abstract
Multimodal pain management strategies are critical in total knee arthroplasty (TKA).
There has recently been a shift toward opioid sparing protocols, yet most publications
continue to use narcotics in the perioperative period. Periarticular injections are
a popular adjunct but studies regarding the optimal medications have high variability
making it difficult to choose the optimal medication. The purpose of this study is
to validate a perioperative, opioid-free protocol and compare two different periarticular
injections without the variability in previous reports. A multimodal pain protocol
was instituted that administered no narcotic medications in the perioperative period.
Over 2 years, primary TKA patients were informally randomized to receive liposomal
bupivacaine (LB), or a cocktail of medications (CO). A total of 189 patients were
included: 101 patients in group LB and 88 patients in group CO. Postoperative opioid
consumption, length of stay, and inpatient distance ambulated were compared across
the two injection groups. In morphine milligram equivalents, group LB consumed a mean
of 20.36 mg of oxycodone versus 23.18 mg in group CO (p = 0.543). For tramadol, group LB consumed 27.24 mg versus 28.69 mg in group CO (p = 0.714). Mean hospital stay was 1.70 days for group LB and 1.72 days for group CO
(p = 0.811). Distance ambulated was 528.4ft for group LB and 499.8ft for group CO (p = 0.477). In the LB group, 50% of patients required no oxycodone, and 12% of them
took neither oxycodone nor tramadol for pain. In the CO group, 40% declined oxycodone
and 10% declined both oxycodone and tramadol. We successfully treated all patients
without narcotic medications in the perioperative period. Although we saw trends for
improvements in group LB, these were small and not clinically meaningful. It appears
that both injections were effective. There is a significant cost difference and medications
should be chosen based on surgeon preference and institutional needs.
Keywords
total knee arthroplasty - arthroplasty perioperative injection medication - nonopioid
perioperative arthroplasty
