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Published on: July 22, 2019
Quiet Knee Rehabilitation Protocol After Primary Total Knee Arthroplasty Is Associated With Lower Opioid Exposure and
Sina Afzal1, Pravjit Bhatti1, Daniel M Alschuler1
1Department of Orthopedic Surgery, Hospital for Special Surgery, New York, New York.
Background:
Conventional early rehabilitation after total knee arthroplasty (TKA) that emphasizes immediate, aggressive range of motion and ambulation may heighten early inflammation and pain. We implemented a supervised 10-day "quiet knee" protocol prioritizing edema control, limited passive range of motion, rest, and telerehabilitation oversight.
Methods:
We retrospectively reviewed 15,646 primary TKAs (quiet knee, n = 841; conventional, n = 14,805) performed from February 1, 2020, to January 15, 2025. We included patients under a strict, quiet knee protocol with telerehabilitation oversight and compared them to a conventional therapy cohort. Primary outcomes were inpatient postoperative morphine milligram equivalents (MMEs) and 90-day postdischarge MMEs prescribed. Cohorts were compared for the primary outcomes using multivariable linear regression adjusting for age, sex, body mass index, and Charlson comorbidity index.
Results:
The mean lengths of stay was shorter in the quiet knee cohort (1.2 versus 1.8 days; P < 0.001). Unadjusted opioid exposure was lower with the quiet knee group: inpatient 52.5 versus 67.5 MMEs and 90-day postdischarge 265.5 versus 332.1 MMEs. In adjusted models, conventional rehabilitation used more opioids: +15 MMEs inpatient (P < 0.001) and +58 MMEs postdischarge (P = 0.001). Patient-reported outcomes improved similarly in both cohorts at two years (Knee Injury and Osteoarthritis Outcome Score for Joint Replacement 79.4 versus 80.2; visual analog scale 19.1 versus 13.2). Complications were low and similar in each group (manipulation under anesthesia: 1.9 versus 0.1%; venous thromboembolism: 0.1 versus 0.3%; 2-year revision: 0.1 versus 0%; quiet knee versus conventional).
Conclusions:
Compared with conventional hands-on, aggressive post-TKA rehabilitation, the quiet knee protocol was associated with lower inpatient and 90-day postdischarge opioid exposure and shorter lengths of stay, without detriment to pain, function, or major complications. This study can serve as a basis for designing a prospective trial to further investigate this alternative therapy protocol post-TKA.
