Outpatient Total Hip and Knee Arthroplasty at an Academic Ambulatory Surgery Center: A Retrospective Review of the First 500 Cases

Updated: Apr 15

VJM 2026 Spring Edition https://doi.org/10.18130/g8tc-qt37

Authors: Joseph Fontana, BA¹, Trent Winkel, MD^1,2, Andrew Rizzi, MD^1,3, Wendy Novicoff, PhD¹

Author Affiliation:

¹University of Virginia Health, Department of Orthopaedic Surgery, Charlottesville, VA, USA

²Great Basin Orthopaedics, Reno, NV, USA

³Aurora Health Care, Department of Orthopedic Surgery, Pleasant Prairie, WI, USA

Conflicts of Interest:

All authors have no conflicts of interest to disclose. No external funding was received for this study. IRB Exempt # 303490

Abstract

Introduction:

In September 2022, an ambulatory orthopaedic surgery center affiliated with a tertiary academic medical center began performing outpatient total hip arthroplasty and total knee arthroplasty. Patients were selected using a predefined screening algorithm designed to identify candidates appropriate for discharge within 23 hours. After an initial review of the first 100 cases demonstrated high rates of protocol adherence and safe discharge, we evaluated the first 500 consecutive patients to assess screening compliance, discharge outcomes, and postoperative complications.

Methods:

A retrospective review was performed of 500 patients (255 total hip arthroplasties, 245 total knee arthroplasties) treated between September 2022 and August 2023. Screening accuracy, discharge timing, and emergency department visits or hospital admissions within 90 days were recorded through comprehensive electronic medical record review.

Results:

Of the 500 patients screened, 89% (n=445) of patients met screening criteria appropriately. Despite this, 98.8% (n=494) were discharged home on the day of surgery and 99.6% (n=498) were discharged within 23 hours. 1.2% (n=6) of patients required either overnight observation or transfer to the main hospital. Within 90 days, 9% (n=45) of patients had at least one emergency department visit or hospital admission. Major complications were infrequent and included prosthetic dislocation (n=2), venous thromboembolism (n=3), prosthetic joint infection (n=1), and periprosthetic fracture (n=1).

Discussion:

Outpatient total joint arthroplasty at an academic ambulatory center demonstrates high rates of successful same-day discharge with low rates of serious complications. Continued use of structured preoperative screening appears to support safe expansion of outpatient total joint arthroplasty.

Introduction

In September 2022, an academic ambulatory orthopaedic surgery center affiliated with a tertiary care hospital began offering outpatient orthopaedic surgeries, including total hip arthroplasty (THA) and total knee arthroplasty (TKA). The facility can admit patients for up to 23 hours but has limited additional care resources, which restricts the complexity of patients it can manage compared to the nearby tertiary care hospital center. To prevent delayed discharges or medical/surgical complications, patients are preoperatively screened using a predetermined algorithm to identify the most suitable candidates for outpatient total joint arthroplasty (TJA).

As part of an initial quality improvement analysis, the first 100 patients who underwent TJA at the ambulatory surgery center were reviewed to evaluate adherence to the preoperative screening protocol, successful same-day discharge, and postoperative complications within 90 days of surgery. In that initial cohort 91% (n=91) of patients met the preoperative screening criteria, resulting in a 100% rate of discharge within 23 hours. Overall, there was a 9% (n=9) utilization of the ED with four readmissions within the first 90 days. The favorable outcomes observed in this initial review prompted further evaluation of a larger cohort of patients treated at the ambulatory surgery center.

Over 1,000 outpatient TJAs have now been completed at the ambulatory surgery center. This project aims to review the first 500 patients to undergo surgery at this facility to assess any changes in the adherence to the preoperative screening protocols as well as any differences in same day discharges and postoperative complications. Over the past several years, outpatient TJA has expanded rapidly across the United States following policy changes and growing institutional experience with recovery protocols. Prior studies have demonstrated that carefully selected patients undergoing outpatient TJA can achieve comparable complication and readmission rates to traditional inpatient procedures.^1,2 As more ambulatory surgical centers adopt TJA, careful patient selection and structured perioperative pathways are essential to maintaining safety and ensuring appropriate resource allocation.

Methods

Prior to being scheduled for surgery, patients were screened using a questionnaire designed to identify individuals who may not be appropriate candidates for outpatient TJA. The questionnaire outlined the following potential exclusion criteria:

Age >80 years old
End organ dysfunction (i.e. severe cardiac, pulmonary, renal, or hepatic disease)
History of solid organ transplant
Chronic anemia
Chronic opioid use
Insulin-dependent diabetes mellitus
Psychiatric illness
Medication prescriptions that require inpatient administration.

In addition to these clinical considerations, the patients were required to understand and show interest in same day discharge and have adequate social support including transportation and home assistance. If patients met these criteria, they were scheduled for surgery and underwent the same preoperative education and clearance/preoperative optimization pathway in place for inpatient/main hospital TJA.

It is important to note that the aforementioned screening questionnaire served as a guideline rather than a strict exclusion algorithm. Final determination of surgical candidacy was made by the attending surgeon, and therefore some variability in interpretation of the screening criteria may have occurred. Additionally, certain criteria such as chronic anemia, chronic opioid use, and psychiatric illness were not defined by strict laboratory thresholds or diagnostic criteria within the questionnaire and therefore allowed for some degree of clinical judgment during the screening process.

We performed a retrospective review of the first 500 patients scheduled for TJA. These consisted of 255 THAs and 245 TKAs, performed between September 2022 and August 2023. Procedures were performed by three fellowship-trained surgeons. Screening process accuracy was assessed, as well as frequency of same-day versus next-day discharge. We examined the reason for same-day discharge failure and any postoperative complications requiring emergency department visits or hospital admission within 90 days of surgery. Each medical record was screened after surgery; this included phone calls, messages, outpatient and inpatient clinical documentation. Care Everywhere (Epic Systems Corporation, Verona, WI) was used to search for any outside admissions or complications.

Results

Adherence to Screening Criteria:

Of the 500 patients reviewed, 445 (89%) met the predefined screening criteria. The most common reasons for not meeting criteria were chronic anemia and chronic opioid use. Four patients were older than 80 years of age, and one patient had insulin-dependent diabetes mellitus.

Length of Stay:

Four patients required overnight observation (two THAs and two TKAs). Two patients did not meet physical therapy clearance criteria, and two were unable to achieve adequate pain control prior to discharge. Two patients (one THA and one TKA) required postoperative transfer for higher-level monitoring. One patient experienced significant chest pain that prompted further evaluation, which was ultimately negative. The second patient required observation for hypotension in the setting of postoperative anemia. All six of these patients had met preoperative screening criteria. Overall, 494 of 500 patients (98.8%) were discharged home on the day of surgery. A total of 498 of 500 patients (99.6%) were discharged within 23 hours.

Post-op Complications:

Within the 90-day postoperative period, 45 of 500 patients (9%) had at least one emergency department visit or hospital admission. Five patients presented for pain-related concerns. Two patients experienced prosthetic hip dislocations; one was managed with closed reduction and one required revision surgery. Three patients presented with deep vein thrombosis or pulmonary embolism. One prosthetic joint infection occurred 47 days after THA and was treated successfully with debridement and implant retention. One periprosthetic femur fracture occurred 12 days following THA and required revision surgery. The remaining emergency department visits were related to dizziness, shortness of breath, chest pain, constipation, or other gastrointestinal complaints. 10 of the 45 patients (22%) who presented to the emergency department or required admission were treated for systemic illness or events unrelated to their surgical procedure.

Among the 55 patients who did not meet screening criteria, five experienced a postoperative issue requiring an emergency department visit or hospital admission within 90 days of surgery. Two patients older than 80 years presented to the emergency department, one for constipation related to postoperative opioid use and one for chest pain with associated pleural effusion. Two patients presented with deep vein thrombosis, one with preoperative chronic anemia and one with chronic opioid use. One patient with a history of opioid use presented for pain-related concerns.

Discussion

In this retrospective review of the first 500 total hip and knee arthroplasties performed in an ambulatory surgical setting, high rates of same-day discharge were achieved with low rates of serious perioperative complications. Although adherence to the predefined screening criteria declined compared to the initial 100-patient cohort (91% to 89%), discharge success remained high, with 98.8% of patients discharged home on the day of surgery and 99.6% discharged within 23 hours.

Only two patients required postoperative transfer for higher-level monitoring. The majority of emergency department visits within 90 days were not related to major arthroplasty-specific complications. Serious surgical events, including prosthetic dislocation, venous thromboembolism, prosthetic joint infection, and periprosthetic fracture, were infrequent.

These findings suggest that structured preoperative screening and close postoperative follow-up can support safe performance of TJA in a carefully selected population. While patient selection criteria broadened over time, outcomes remained favorable, indicating that the screening approach continues to identify appropriate candidates for outpatient management.

This study has several limitations. It represents a retrospective review from a single academic ambulatory center and may not be generalizable to all practice settings. There was no inpatient comparison cohort, limiting the ability to assess relative risk compared with hospital-based arthroplasty. Although comprehensive medical record review was performed, complications treated outside the health system may not have been fully captured. In addition, formal cost analysis and patient-reported outcome measures were not included. Despite these limitations, this cohort provides meaningful insight into early experience with outpatient TJA in an academic environment.

As ambulatory TJA continues to expand, maintaining strict screening protocols and close perioperative care will remain important to maintaining patient safety.

References

1. Lan RH, Samuel LT, Grits D, Kamath AF. Contemporary Outpatient Arthroplasty Is Safe Compared with Inpatient Surgery: A Propensity Score-Matched Analysis of 574,375 Procedures. J Bone Joint Surg Am. 2021 Apr 7;103(7):593-600. doi: 10.2106/JBJS.20.01307. PMID: 33646984.

2. Rullán PJ, Xu JR, Emara AK, Molloy RM, Krebs VE, Mont MA, Piuzzi NS. Major National Shifts to Outpatient Total Knee Arthroplasties in the United States: A 10-Year Trends Analysis of Procedure Volumes, Complications, and Healthcare Utilizations (2010 to 2020). J Arthroplasty. 2023 Jul;38(7):1209-1216.e5. doi: 10.1016/j.arth.2023.01.019. Epub 2023 Jan 21. PMID: 36693513.