Physical Therapy Use, Costs, and Value for Latent Classes of Good vs Poor Outcome in Patients Who Catastrophize About Their Pain Prior to Knee Arthroplasty.

Journal Article (Journal Article;Multicenter Study)

OBJECTIVE: To examine use, costs, and value of physical therapy (PT) among subgroups. DESIGN: We conducted an observational study of data from a randomized trial of a pain coping skills intervention. Good and poor outcome subgroups were determined based on Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) Pain and Physical Function scores. The use and costs of PT care as well as changes in WOMAC Pain and Physical Function scores over 4 time periods during a 1-year follow-up were reported. We compared the number of PT visits, total PT costs, and cost per 1-unit improvement in WOMAC scores for the 2 latent subgroups. SETTING: Five academic medical centers. PARTICIPANTS: Patients who catastrophized about their pain prior to knee arthroplasty (N=384). INTERVENTIONS: Pain coping skills training, arthritis education, and usual care. MAIN OUTCOME MEASURES: The WOMAC Pain Scale was the primary outcome. RESULTS: The value of PT was lower and the cost of PT was higher for poor vs good outcome subgroups beginning 2 months after knee arthroplasty. For example, during the 2- to 6-month period, participants in the poor outcome subgroup incurred a PT cost of $5181.22 per 1-unit improvement in WOMAC Pain compared with $437.87 per 1-unit improvement in WOMAC Pain for the good outcome subgroup (P<.001). From the 6- to 12-month period, WOMAC scores worsened for the poor outcome subgroup, indicating no benefit from PT. CONCLUSIONS: Patients in 2 latent classes demonstrated clinically important differences in value of PT. Future research should identify rehabilitation-based interventions that reduce utilization and enhance effectiveness for patients at high risk for poor outcome.

Full Text

Duke Authors

Cited Authors

  • Orndahl, CM; Perera, RA; Hung, A; Dumenci, L; Riddle, DL

Published Date

  • July 2021

Published In

Volume / Issue

  • 102 / 7

Start / End Page

  • 1347 - 1351

PubMed ID

  • 33689694

Pubmed Central ID

  • PMC8263505

Electronic International Standard Serial Number (EISSN)

  • 1532-821X

Digital Object Identifier (DOI)

  • 10.1016/j.apmr.2021.02.004


  • eng

Conference Location

  • United States