Early Clinical Outcomes of "Lemon-Dropped" Complex Primary Total Joint Arthroplasty Patients to a Tertiary Care Center

J Arthroplasty. 2024 Feb 5:S0883-5403(24)00081-0. doi: 10.1016/j.arth.2024.01.058. Online ahead of print.

Abstract

Background: In the era of value-based care, pressures lead to cherry-picking healthier patients and lemon-dropping riskier patients to higher levels-of-care. This study examined whether "lemon-dropped" primary total joint arthroplasty (pTJA) patients require increased health care resources and experience worse outcomes.

Methods: This was a retrospective cohort study of all pTJAs at one tertiary care center in 2022, excluding bilaterals, acute fractures, oncologic cases, and conversion hips. Patients were classified via referral pattern as simple or complex (referred for medical or surgical complexity). Primary outcomes were implant costs and any emergency department visit, readmission, reoperation, or complication within 90 days. Secondary outcomes were distance traveled to the hospital, anesthesia type, estimated blood loss, case duration, time in the recovery unit, length of stay, and discharge disposition. Outcomes were assessed via electronic medical record review and analyzed via Fisher's exact and unpaired Welch's t-tests.

Results: In total 641 pTJAs (322 hips, 319 knees) met inclusion criteria; 10.3% were complex referrals. Complex patients were younger (59 versus 66 years, P < .05) and more often non-White (41 versus 31%, P < .001), non-English speaking (11 versus 7%, P < .001), and had nonprimary osteoarthritis as a surgical indication (59 versus 12%, P < .001), but had similar Charlson Comorbidity Index and American Society of Anesthesiologists scores. Complex patients had increased odds of 90-day emergency department visits (OR [odds ratio] = 2.11, P = .04), 90-day complications (OR = 2.63, P < .001), and non-home discharge (OR = 2.60, P = .006); higher mean relative implant costs (1.31x, P < .001); longer time in the operating room (181 versus 158 minutes P < .001), time in surgery (125 versus 105 minutes, P < .001), and length of stay (3.2 versus 1.7 days, P = .005).

Conclusions: "Lemon-dropped" pTJAs had worse early clinical outcomes and higher health care utilization, despite a control group with patients ill enough to utilize a tertiary care center as their medical home. Reimbursement models and evaluation metrics must account for these differences.

Keywords: bundled payment; complex joint replacement; healthcare cost; primary total joint arthroplasty; tertiary-care referral.