Patient factors associated with referral to inpatient rehabilitation following knee or hip arthroplasty in a public sector cohort : a prognostic factor study

Rationale, aims and objectives: Inpatient rehabilitation following total knee or hip arthroplasty (TKA, THA) is resource intensive and expensive. Understanding who is referred is integral to the discourse concerning service and cost reform. This study aimed to determine patient prognostic factors associated with referral to inpatient rehabilitation following TKA or THA in a public sector setting. In this setting, surgeon or patient choice does not drive referral. Method: Prognostic factor research based on secondary analysis of prospectively collected data. Consecutive people undergo elective, primary TKA, or THA at a high-volume public hospital. The outcome was referral to inpatient rehabilitation after acute care. Patient variables including sociodemographic, comorbidity, and complication details were used in multivariable logistic regression to determine the prognostic factors associated with referral. Results: Five hundred twenty people were included; 9.2% experienced the outcome. In the multivariable model, acute complications (OR 3.6, 95% CI 1.6-7.8), TKA surgery (OR 3.1, 95% CI 1.0-9.4), renal disease (OR 4.4, 95% CI 1.4-13.3), and higher body mass index (OR 1.1, 95% CI 1.0-1.2) were associated with referral; unilateral surgery (OR 0.1 (95% CI 0.01-0.2) and previous arthroplasty (OR 0.3 (95% CI 0.1-0.8) were protective. There were no significant associations found for sociodemographic factors (such as gender and residential status) in the multivariable model. Conclusion: In the absence of choice, physical impairment and health factors are associated with referral to inpatient rehabilitation following TKA or THA.