Abstract
Previous studies of early versus late manipulation under anesthesia (MUA) do not report
on postoperative opioid utilization or revisions and focused on small single-institution
retrospective cohorts. The PearlDiver Research Program (www.pearldiverinc.com), which uses an all-inclusive insurance database, was used to identify patients undergoing
primary total knee arthroplasty (TKA) who received (1) late MUA (>12 weeks), (2) early
MUA (≤12 weeks), or (3) TKA only. To develop the control group cohort of TKA-only
patients, 3:1 matching was conducted using 11 risk factor variables deemed significant
by chi-squared analysis. Complications and opioid utilization were compared through
multivariate regression analysis, controlling for age, gender, and Charlson Comorbidity
Index. The risk of TKA revision was assessed through Cox-proportional hazards modeling
and Kaplan–Meier survival analysis with log-rank test. Between 2011 and 2017, 2,062
TKA patients with early MUA, 1,112 TKA patients with late MUA, and a control cohort
of 8,327 TKA-only patients were identified in the database. The percent of patients
registering opioid use decreased from 54.6% 1 month pre-MUA to 4.6% (p < 0.0001) 1 month post-MUA following early MUA, whereas only from 32.6 to 10.4% (p < 0.0001) following late MUA. Late MUA was associated with higher risk of repeat MUA
at 6 months (adjusted odds ratio [aOR] = 2.74, p < 0.0001), 1 year (aOR = 2.66, p < 0.0001), and 2 years (aOR = 2.63, p < 0.0001) following index MUA. Hazards modeling and survival analysis showed increased
risk of TKA revision following late MUA (adjusted hazard ratio [aHR] = 3.50, 95% confidence
interval [CI]: 2.77–4.43, p < 0.0001) compared to early MUA (aHR = 2.15, 95% CI: 1.72–2.70, p < 0.0001), with significant differences in survival to revision curves (p < 0.0001). When compared to early MUA at 1 year, late MUA was associated with a significantly
increased risk of prosthesis explantation (aOR = 2.89, p = 0.0026 vs. aOR = 0.93, p = 0.8563). MUA within 12 weeks after index TKA had improved pain resolution and significant
curtailing of opioid use. Furthermore, late MUA was associated with prolonged opioid
use, increased risks of revision, as well as prosthesis explantation, supporting screening
and early intervention in cases of slow progression and stiffness. The level of evidence
of this study is III.
Keywords
total knee arthroplasty - arthrofibrosis - manipulation under anesthesia - explantation
- opioid
