Associations between preoperative physical therapy and post-acute care utilization patterns and cost in total joint replacement

BACKGROUND

Health-care costs following acute hospital care have been identified as a major contributor to regional variation in Medicare spending. This study investigated the associations of preoperative physical therapy and post-acute care resource use and its effect on the total cost of care during primary hip or knee arthroplasty.

METHODS

Historical claims data were analyzed using the Centers for Medicare & Medicaid Services Limited Data Set files for Diagnosis Related Group 470. Analysis included descriptive statistics of patient demographic characteristics, comorbidities, procedures, and post-acute care utilization patterns, which included skilled nursing facility, home health agency, or inpatient rehabilitation facility, during the ninety-day period after a surgical hospitalization. To evaluate the associations, we used bivariate and multivariate techniques focused on post-acute care use and total episode-of-care costs.

RESULTS

The Limited Data Set provided 4733 index hip or knee replacement cases for analysis within the thirty-nine-county Medicare hospital referral cluster. Post-acute care utilization was a significant variable in the total cost of care for the ninety-day episode. Overall, 77.0% of patients used post-acute care services after surgery. Post-acute care utilization decreased if preoperative physical therapy was used, with only 54.2% of the preoperative physical therapy cohort using post-acute care services. However, 79.7% of the non-preoperative physical therapy cohort used post-acute care services. After adjusting for demographic characteristics and comorbidities, the use of preoperative physical therapy was associated with a significant 29% reduction in post-acute care use, including an $871 reduction of episode payment driven largely by a reduction in payments for skilled nursing facility ($1093), home health agency ($527), and inpatient rehabilitation ($172).

CONCLUSIONS

The use of preoperative physical therapy was associated with a 29% decrease in the use of any post-acute care services. This association was sustained after adjusting for comorbidities, demographic characteristics, and procedural variables.

CLINICAL RELEVANCE

Health-care providers can use this methodology to achieve an integrative, cost-effective, patient care pathway using preoperative physical therapy.