A matched case–control comparison of hospital costs and outcomes for knee replacement patients admitted postoperatively to acute care versus rehabilitation

For select total knee arthroplasty (TKA) patients, we have established an alternative pathway to bypass the acute care surgical ward and directly admit patients from the post-anesthesia care unit to on-campus rehabilitation. We retrospectively examined whether this ‘fast track’ pathway decreased costs and improved patient outcomes. After reviewing records of consecutive primary unilateral TKA patients over a 15-month period, each patient admitted to rehabilitation was matched with a control admitted to the acute care ward. The primary outcome was estimated total hospitalization cost (length of stay in days multiplied by the average cost per day). Secondary outcomes were length of stay, in-hospital pain scores, opioid use, maximum ambulatory distance and 30-day readmission, morbidity, and mortality. Of the 262 TKA patients during the study period, 14 were admitted to rehabilitation and were matched to 14 patients admitted to acute care. Estimated total hospitalization cost [median (10th–90th percentiles)] was US$30,755 (US$23,066–38,444) for ward patients compared to US$17,620 (US$13,215–33,918) for rehabilitation patients (P = 0.006). This difference [mean (95% CI)] was US$10,143 (US$2174–18,112). There were no other differences. For facilities similar to ours, direct postoperative admission of select TKA patients to subacute rehabilitation may be less costly than acute care and may not negatively affect outcomes.