Abstract
Background: With an aging population, knee osteoarthritis (KOA) is increasingly more prevalent. A significant number of patients with advanced KOA require total knee arthroplasty (TKA). Preoperative physical function predicts postoperative outcomes. We hypothesized that preoperative water exercise to improve preoperative physical function will improve postoperative outcomes after TKA.Methods: We conducted a randomized controlled trial in 43 participants who were scheduled for TKA and scored at or below 50th percentile in mobility assessment tool-sf (MAT-sf). All enrolled participants were assessed on 1) clinical osteoarthritis symptom severity using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), 2) physical function using Short Physical Performance Battery (SPPB), 3) self-reported mobility using Mobility Assessment Tool-short form (MAT-sf), 4) depression using Geriatric Depression Scale-short form (GDS-sf), 5) cognitive function using Montreal Cognitive Assessment (MoCA). High-sensitivity-C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) levels were analyzed. Participants were randomly assigned to the aquatic exercise intervention (AEI) or usual care group. The AEI was conducted three times a week for 4-8 weeks, with each session lasting for 60 minutes. Participants in both groups were evaluated within one week before their scheduled surgery, as well as 4 weeks after the surgery. Logistic regressions were used to examine the associations between the intervention and unfavorable outcomes.Results: The mean age was 67.1 (±6.2), 44% were female, 74% were White. There is no statistically significant difference in combined outcome of any complication, unscheduled ER visit, and disposition to nursing home or rehab facility by AEI. However, AEI was associated with more favorable functional outcomes including WOMAC scores, chair-stand, MAT-sf, as better mood and cognition and lower blood pressure in multivariable analyses.Conclusion: 4-8 weeks of aquatic exercise intervention resulted in improved functional outcomes in patients undergoing TKA. A larger study is warranted to explore the role of water exercise in clinical and functional outcomes of TKA.Trial registration: This clinical trial was registered at ClinicalTrials.gov with ClinicalTrials.gov Identifier of NCT02773745. The date of registration was March 16th 2016. The URL of the trial registry record is https://www.clinicaltrials.gov/ct2/show/NCT02773745?term=water&recrs=e&cond=Osteoarthritis%2C+Knee&cntry=US&draw=2&rank=2.