Variation in Outcomes and Number of Visits Following Care Guideline Implementation: Part 2 of an Analysis of 12,355 Patients After Total Knee Arthroplasty

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Lippincott, Williams & Wilkins

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Journal of Orthopaedic & Sports Physical Therapy

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Original Item ID

DOI: 10.2519/jospt.2022.11370


OBJECTIVE: To describe the variation in outcomes and number of visits before and after implementing a care guideline for total knee arthroplasty (TKA) rehabilitation.

DESIGN: Nonrandomized intervention study.

METHODS: We compared 2558 patients with TKA who received care that was not standardized (non-care guideline [NCG] group) to 9797 patients with TKA who received care according to the care guideline (CG). We fit 2 Bayesian hierarchical linear regression models using the Knee Outcome Survey – Activities of Daily Living (KOS-ADL) change score and number of physical therapy (PT) visits as the response variables, controlling for relevant predictor variables. We also compared the ratio of the standard deviations of the KOS-ADL change scores and the number of PT visits within and between clinics.

RESULTS: The overall estimated mean improvement in KOS-ADL change score was 23.0 points (95% confidence interval [CI]: 20.3, 25.7) in the NCG group and 28.7 points (95% CI: 27.5, 29.7) in the CG group; the mean difference was 5.6 (2.7–8.6). Mean KOS-ADL change scores were higher in the CG group than the NCG group in every clinic, although only 8 clinics improved significantly. The number of PT visits did not change meaningfully (NCG: mean, 10.7 [95% CI: 9.9, 11.5]; CG: mean, 10.5 [95% CI: 9.9, 10.9]). Variation in KOS-ADL change score decreased by 4% within clinics (CG-NCG ratio: 0.96 [95% CI: 0.93, 0.99]) and 63% between clinics (CG-NCG ratio: 0.37 [95% CI: 0.21, 0.62]). Variation in number of visits decreased by 7% within clinics (CG-NCG ratio: 0.93 [95% CI: 0.90, 0.96]) and 19% between clinics (CG-NCG ratio: 0.81 [95% CI: 0.39, 1.49]).

CONCLUSION: Implementing a care guideline for TKA rehabilitation may improve outcomes and reduce unwarranted variation in practice within clinics and especially between clinics within a large health care system.


Journal of Orthopaedic & Sports Physical Therapy, Vol. 53, No. 3 (March 2023): 107-158. DOI.