Outpatient and Inpatient Unicompartmental Knee Arthroplasty Procedures Have Similar Short-Term Complication Profiles

Safety evaluation of outpatient vs inpatient unicompartmental knee arthroplasty: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to evaluate the safety of outpatient and inpatient Unicompartmental Knee Arthroplasty (UKA) based on the incidence of adverse events.

METHOD

A systematic search of the literature was performed in October 2022 on PubMed, Web of Science, Cochrane library, and Embase. The Meta package for R was used to perform the meta-analysis.

RESULT

Five studies with a total of 26,301 patients were included. 5813 patients (22.1%) were treated with outpatient UKA, and 20,488 patients (77.9%) were treated with inpatient UKA. There were no statistically significant differences in the incidence of total complications (RR = 1.36, 95% CI = 0.64-2.89, Z = 0.79, P = 0.43), readmission (RR = 1.02, 95% CI = 0.40-2.60, Z = 0.05, P = 0.96), and venous thrombosis (RR = 1.43, 95% CI = 0.96-2.11, Z = 1.78, P = 0.08). Incidence rates were lower in outpatient UKA regarding urinary tract infection (RR = 1.48, 95% CI = 1.07-2.04, Z = 2.40, P = 0.02), pulmonary embolus (RR = 7.48, 95% CI = 1.80-31.17, Z = 2.76, P < 0.01), and transfusion (RR = 2.77, 95% CI = 1.63-4.71, Z = 3.78, P < 0.01).

CONCLUSION

In summary, outpatient UKA shows lower incidences of hospital-acquired complications such urinary tract infection, pulmonary embolus, and transfusion. It's worth noting that the incidences of total complications, readmission, and venous thrombosis in outpatient UKA were not higher than the incidences of inpatient UKA, suggestting that outpatient UKA can be considered a safe alternative to inpatient UKA.

Using orthopaedic health care resources efficiently: A cost analysis of day surgery for unicompartmental knee replacement

BACKGROUND

Day surgery for unicompartmental knee replacement (UKR) could potentially reduce hospital costs. We aimed to measure the impact of introducing a day surgery UKR pathway on mean length of stay (LOS) and costs for the UK NHS, compared to an accelerated inpatient pathway. Secondly, the study aimed to compare the magnitude of costs using three costing approaches: top-down costing; simple micro-costing; and real-world costing.

METHODS

We conducted an observational, before-and-after study of 2,111 UKR patients at one NHS hospital: 1,094 patients followed the day surgery pathway between September 2017 and February 2020; and 1,017 patients followed the accelerated inpatient pathway between September 2013 and February 2016. Top-down costs were estimated using Average NHS Costs. Simple micro-costing used the cost per bed-day. Real-world costs for this centre were estimated by costing actual changes in staffing levels.

RESULTS

532 (48.5%) patients in the day surgery pathway were discharged on the day of surgery compared with 36 (3.5%) patients in the accelerated inpatient pathway. The day surgery pathway reduced the mean LOS by 2.2 (95% CI: 1.81, 2.53) nights and was associated with an 18% decrease in Average NHS Costs (p < 0.001). Mean savings were £1,429 per patient with the Average NHS Costs approach, £905 per patient with the micro-costing approach, and £577 per patient with the "real-world" costing approach. Overall, moving NHS UKR surgeries to a day surgery pathway could save the NHS £8,659,740 per year.

CONCLUSION

Day surgery for UKR could produce substantial cost savings for hospitals and the NHS.

Trends and outcomes in the surgical management of young adults with knee osteoarthritis using high tibial osteotomy and unicompartmental knee arthroplasty

INTRODUCTION

A significant portion of knee osteoarthritis is diagnosed in patients under the age of 55, where greater activity demands make total knee arthroplasty less desirable. High tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) are useful alternatives, but there is little understanding of which procedure is advantageous. Hence, this study examines the utilization, complication, and reoperation rates among the HTO vs. UKA in young patients with primary osteoarthritis.

METHODS

A retrospective review of the National Surgical Quality Improvement Program was performed to identify 2318 patients < 55 years of age who received either a HTO or UKA for primary osteoarthritis between 2011 and 2021. Bivariate analyses compared preoperative and intraoperative characteristics among each procedure. Then, multivariate analyses examined if either procedure was associated with worse 30-day postoperative complications or need for reoperation, independent of the statistically significant pre- and intraoperative disparities.

RESULTS

UKAs were performed 14.2 times more commonly than HTOs, and the patients selected for HTO were more likely to be younger, have a lower BMI, have the healthiest ASA Class score, and less likely to have hypertension requiring medication (p < 0.001). HTOs took 17.5% longer to perform and had a longer average length of stay (p < 0.001), while UKAs were more likely to be performed out-patient (p < 0.001). HTOs also had higher rates of serious complications (p = 0.02), overall complications (p = 0.004), and need for reoperation (p = 0.004). Multivariate modelling demonstrated that procedure type was not a predictor of serious complications, but the use of HTO was significantly associated with any complications (odds ratio = 3.63, p = 0.001) and need for reoperation (3.21, p = 0.029).

CONCLUSION

Although healthier patients were selected for HTOs, UKAs were found to have a lower risk of complications and immediate reoperation. Additionally, UKAs had the advantage of lower operative burden, shorter length of stay, and a higher efficacy in outpatient settings.

The safety and efficacy of unicompartmental knee arthroplasty in outpatient surgical centers: A systematic review and meta-analysis

BACKGROUND

Unicompartmental knee arthroplasty (UKA) is an effective treatment method for knee osteoarthritis. With the development and implementation of enhanced recovery after surgery, UKA is now increasingly performed in outpatient surgical centers. However, there is ongoing debate regarding the safety and effectiveness of performing UKA in outpatient settings.

METHODS

The search was performed to retrieve randomized controlled trials and cohort studies on outpatient UKA from PubMed, Cochrane Library, EMbase, CNKI, and WanFangData databases. The search was conducted from the inception of the databases until August 31, 2023. After independent screening, data extraction, and risk of bias evaluation by two researchers, meta-analysis was performed using RevMan 5.4 software.

RESULTS

A total of eight studies involving 18,411 patients were included. The results showed that the postoperative transfusion rate in the outpatient group was lower than that in the inpatient group [OR = 0.36, 95%CI (0.24, 0.54), p < 0.00001], and the difference was statistically significant. However, there was no significant difference between the two groups in terms of readmission rate, reoperation rate, surgical site infection, and periprosthetic fracture. The differences were not statistically significant.

CONCLUSION

Compared to the traditional inpatient route, the blood transfusion rate for single-condyle replacement in the outpatient operation center is lower, and there is no significant difference in readmission rate, reoperation rate, surgical site infection, and periprosthesis fracture. The outpatient approach to UKA is safe, feasible, and highly satisfactory for patients. However, the results have certain limitations, and a rigorous preoperative complication risk assessment can minimize the risk of UKA in outpatient surgery centers.

TRIAL REGISTRATION

PROSPERO number CRD42023405373.

Outpatient Total Ankle Arthroplasty (TAA) as a Rising Alternative to Inpatient TAA: A Database Analysis

BACKGROUND

There is growing evidence that total ankle arthroplasty (TAA) can safely be performed as an outpatient procedure, with the benefit of decreased health care expenses and improved patient satisfaction. The purpose of our study was to compare readmissions, arthroplasty failures, infections, and annual trends between outpatient and inpatient TAA using a large publicly available for-fee database.

METHODS

The PearlDiver Database was queried to identify outpatient and inpatient TAA-associated claims for several payer types from January 2010 to October 2021. Preoperative patient characteristics and annual trends were compared for inpatient and outpatient TAA. International Classification of Diseases, Ninth and Tenth Revision, diagnosis codes were used to identify infections and arthroplasty failures. Complications rates were compared after matching patients by age, gender, and the following comorbidities: diabetes, smoking, congestive heart failure (CHF), hypertension (HTN), obesity, and chronic kidney disease (CKD).

RESULTS

A total of 12 274 patients were included in the final exact-matched analysis for complications, with 6137 patients in each group. Outpatients had a significantly lower rate of readmission within 90 days (2.6% vs 4.0%, P < .001), arthroplasty failure (4.1% vs 6.9%, P < .001), and infection (2.4% vs 3.1%, P = .015). Among database enrollees, outpatient TAA has risen in proportion to inpatient TAA from 2019 to 2021.

CONCLUSION

Outpatient TAA had lower rates of risk-adjusted readmission, arthroplasty failure, and infection compared to inpatient TAA.

LEVEL OF EVIDENCE

Level III, retrospective comparative database study.

Complications after lateral unicompartmental knee arthroplasty in a fast-track setting: a prospective cohort study of 170 procedures

BACKGROUND AND PURPOSE

In existing studies on fasttrack unicompartmental knee arthroplasty (UKA), the majority of surgeries are medial. There are substantial differences between lateral and medial UKA, which is why outcomes cannot automatically be compared. To gain information on the feasibility and safety of fast-track protocols in lateral UKAs, we investigated length of stay (LOS) and early complications after lateral UKA, performed using a fast-track protocol in well-established fast-track centers.

PATIENTS AND METHODS

We retrospectively evaluated prospectively collected data on patients undergoing lateral UKA in a fast-track setup from 2010 to 2018 at 7 Danish fast-track centers. Data on patient characteristics, LOS, complications, reoperations, and revisions was analyzed using descriptive statistics. Safety and feasibility were defined as complication and reoperation rates within 90 days comparable to non-fast track lateral UKA or fast-track medial UKA.

RESULTS

We included 170 of patients with a mean age of 66 (SD 12) years. Median LOS was 1 day (interquartile range 1-1), which was unchanged from 2012-2018. 18% were discharged on the day of surgery. Within 90 days, 7 patients experienced medical complications and 5 patients experienced surgical complications. 3 patients underwent reoperation, 2 were soft tissue revisions and the third was removal of an exostosis due to catching of the patella. 1 patient was revised due to a bearing dislocation.

CONCLUSION

Our findings suggest that lateral UKA in a fast-track setting is feasible and safe.

An ACS-NSQIP Analysis of Unicompartmental Knee Arthroplasty Trends from 2013 to 2018

Unicompartmental knee arthroplasty (UKA) volume has increased with advances in implant design, perioperative protocols, and patient selection. This study analyzed national trends of UKA from 2013 to 2018 and the relationship between patient demographics and postoperative outcomes. Data on UKA (CPT 27446) from 2013 to 2018 was collected from the National Surgical Quality Improvement Program (NSQIP). Variables collected included patient demographics, American Society of Anesthesiology classification, functional status, NSQIP morbidity probability, operative time, length of stay, 30-day reoperation, and readmission rates. There was an increase in outpatient UKAs performed (920 in 2013; 11,080 in 2018) (p < 0.0001). Analysis of variance from 2013 to 2018 revealed significant decrease in patient body mass index (BMI) (32.5 in 2013; 31.5 in 2018) (p < 0.01) and NSQIP morbidity probability (0.014 in 2013; 0.011 in 2018) (p < 0.0001). Operative time increased (79.1 minutes in 2013; 84.4 minutes in 2018) (p < 0.01), but length of stay decreased (0.9 days in 2013; 0.5 days in 2018) (p < 0.0001). The number of all-cause and related readmissions decreased significantly (p < 0.045; p < 0.01). Age, male gender, BMI >40 and chronic obstructive pulmonary disease (COPD) were significant predictors for 30-day readmission. BMI >40 was a significant predictor for discharge destination. UKA has seen a rise in incidence from 2013 to 2018 with an increasing number of outpatient UKAs. Operative times and 30-day readmissions have both decreased in this time. BMI > 40 is predictive for discharge destination after UKA, while age, male gender, BMI >40, and COPD are independent risk factors for 30-day readmission.

Comparison of day-case versus inpatient uni-compartmental knee replacement

BACKGROUND

Uni-compartmental knee replacement (UKR) is an alternative to total knee replacement for patients who have isolated compartment osteoarthritis. Studies have demonstrated that UKR can be safely performed as a day-case procedure without a negative impact on complication rates. The aim of this study was to compare the clinical outcomes between day-case and inpatient UKRs.

METHODS

A single surgeon prospective case-controlled study was performed, comparing data between day-case UKRs and inpatient UKRs. This included longitudinal analysis of patient reported outcome measures (PROMs); including the Oxford Knee Score, Knee Injury and Osteoarthritis Outcome Score, Short Form 12-item Health Survey, EQ-5D-5L and the Self-administered Comorbidity Questionnaire. Post-operative pain scores (visual analogue scale), unplanned post-operative hospital reattendance rates and complications were also analysed.

RESULTS

Overall, 100% of day-case patients were successfully discharged on the same day. Both inpatient (n = 23) and day-case (n = 23) UKRs demonstrated a significant within group longitudinal improvement of PROM scores (p < 0.05) following surgery. However, the post-operative PROM scores were significantly higher in the day-case group as compared to the inpatient group (p < 0.05). Both groups had comparable post-operative pain scores, but the day-case group demonstrated fewer unplanned reattendances and post-operative complications.

CONCLUSION

The clinical outcomes of day-case UKR are superior to inpatient UKR. Careful patient selection and a robust multidisciplinary patient pathway are the key components to success of day-case joint replacement surgery.

LEVEL OF EVIDENCE

Prospective Case-Control Study, level III.

Overnight joint replacement surgery: a pilot Australian study

BACKGROUND

With a stretched healthcare system and elective surgery backlog, measures to improve efficiency and decrease costs associated with surgical procedures need to be prioritized. This study compares the benefits of multi-disciplinary involvement in an enhanced recovery after surgery (ERAS) protocol-led overnight model following total hip replacement (THR) and total knee replacement (TKR).

METHODS

Patients in each of two private hospitals undergoing THR or TKR were prospectively enrolled. One hospital (Overnight) was fully committed to the ERAS protocol implementation on all levels and formed the treatment group while in the other hospital (control), patients only had the anaesthetic and operative procedure as part of the ERAS protocol but did not follow the perioperative measures of the protocol. Outcomes on hospital length of stay (LOS), inpatient rehabilitation, functional outcomes, satisfaction, adverse events and readmission rates were investigated.

RESULTS

Median LOS in the Overnight group was significantly smaller than in the control group (1 vs. 3 days, P < 0.0001). The Overnight group had lower rates of inpatient rehabilitation utilization (4% vs. 41.2%, P < 0.0001), similar improvements in functional hip and knee scores and no increased rate of adverse events or readmission. All patients in both groups were satisfied with their treatment.

CONCLUSION

Overnight THR and TKR can safely be performed in the majority of patients, with a multi-disciplinary approach protocol and involvement of all perioperative stakeholders.

Readmissions and mortality after outpatient vs inpatient unicompartmental knee arthroplasty in Denmark - A propensity score matched study of 5,384 procedures

BACKGROUND

Limited nationwide data on the development of outpatient unicompartmental knee arthroplasty (UKA) practice and patient safety exist. The primary objective of this study on patients receiving a medial or lateral UKA was to investigate 7-, 30- and 90-day readmission risk and 90-day mortality in outpatient vs inpatient surgeries. Secondary to investigate the nationwide development of outpatient UKA surgery in 2014-2018.

METHODS

Included patients received a medial or lateral UKA in the period January 1, 2014 to December 31, 2018 in any Danish hospital. Data were collected from the Danish National Patient Register. The cohort consisted of 1,059 outpatient and 4,325 inpatient surgeries, hereof 5,182 medial and 202 lateral UKA. After propensity score matching (1:1) 1,057 patients were included in each group.

RESULTS

We found a 7-day readmission risk of 1.5 % vs 1.4 % (p = 0.8), 30-day readmission risk of 2.6 % vs 3.2 % (p = 0.3), and 90-day readmission risk of 4.2 % vs 4.8 % (p = 0.4) after outpatient vs inpatient UKA. Similar results were found after matching. We found no significant differences in 90-day mortality for the unmatched or matched cohorts. The amount of outpatient UKA surgeries in Denmark increased from 86 in 2014 to 214 in 2018.

CONCLUSION

Outpatient medial or lateral UKA seem to be as safe as inpatient UKA on a nationwide basis.

Safety and efficacy of outpatient hip and knee arthroplasty: a systematic review with meta-analysis

INTRODUCTION

This systematic review aimed to assess the safety and efficacy of outpatient joint arthroplasty (OJA) pathways compared to inpatient pathways.

MATERIALS AND METHODS

An electronic literature search was conducted to identify eligible studies. Studies comparing OJA with inpatient pathways-following hip and/or (partial) knee arthroplasty-were included. Included studies were assigned-based on OJA definition-to one of the following two groups: (1) outpatient surgery (OS); outpatient defined as discharge on the same day as surgery; and (2) semi-outpatient surgery (SOS); outpatient defined as discharge within 24 h after surgery with or without an overnight stay. Methodological quality was assessed. Outcomes included (serious) adverse events ((S)AEs), readmissions, successful same-day discharge rates, patient-reported outcome measures (PROMs) and costs. Meta-analyses and subgroup analyses by type of arthroplasty were performed when deemed appropriate.

RESULTS

A total of 41 studies (OS = 26, SOS = 15) met the inclusion criteria. One RCT and 40 observational studies were included, with an overall risk-of-bias of moderate to high. Forty studies were included in the meta-analysis. Outpatients (both OS and SOS) were younger and had a lower BMI and ASA class compared to inpatients. Overall, no significant differences between outpatients and inpatients were found for overall complications and readmission rates, and improvement in PROMs. By type of arthroplasty, only THAs in OS pathways were associated with fewer AEs [OR = 0.55 (0.41-0.74)] compared to inpatient pathways. 92% of OS patients were discharged on the day of surgery. OJA resulted in an average cost reduction of $6.797,02.

CONCLUSION

OJA pathways are as safe and effective as inpatient pathways in selected populations, with a potential reduction of costs. Considerable risk of bias in the majority of studies emphasizes the need for further research.

Demographics and surgery-related complications lead to 30-day readmission rates among knee arthroscopic procedures

PURPOSE

The study objectives were (1) to evaluate risk factors related to 30-day hospital readmissions after arthroscopic knee surgeries and (2) to determine the complications that may arise from surgery.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database data from 2012 to 2017 were researched. Patients were identified using Current Procedural Terminology codes for knee arthroscopic procedures. Ordinal logistic fit regression and decision tree analysis were used to examine study objectives.

RESULTS

There were 83,083 knee arthroscopic procedures between 2012 and 2017 obtained from the National Surgical Quality Improvement Program database. The overall readmission rate was 0.87%. The complication rates were highest for synovectomy and cartilage procedures, 1.6% and 1.3% respectively. A majority of readmissions were related to the procedure (71.1%) with wound complications being the primary reason (28.2%) followed by pulmonary embolism and deep vein thrombosis, 12.7% and 10.6%, respectively. Gender and body mass index were not significant factors and age over 65 years was an independent risk factor. Wound infection, deep vein thrombosis, and pulmonary embolism were the most prevalent complications.

CONCLUSION

Healthcare professionals have a unique opportunity to modify treatment plans based on patient risk factors. For patients who are at higher risk of inferior surgical outcomes, clinicians should carefully weigh risk factors when considering surgical and non-surgical approaches.

LEVEL OF EVIDENCE

III.

Unicompartmental Knee Arthroplasty in Octogenarians: A National Database Analysis Including Over 700 Octogenarians

Background

Unicompartmental knee arthroplasty (UKA) may be considered for select patients to relieve pain and restore function of the knee joint. Little research to date has explored the complication profile of UKA in an older population. The current study uses a large national surgical database to examine the 30-day postoperative adverse events in octogenarians compared with those in nonoctogenarians.

Material and methods

The 2012-2018 National Surgical Quality Improvement Program database was queried for all patients undergoing UKA for osteoarthritis. Those patients aged 80 years or older composed the octogenarian age group. Demographics and medical comorbidities were cataloged, in addition to 30-day adverse events. Multivariate regression analysis controlled for differences in demographics and comorbidities. Significance was set at P < .05.

Results

A total of 10,103 patients undergoing UKA were identified, of which 728 (7.2%) were octogenarians. The octogenarian cohort had significantly higher comorbidity burden than nonoctogenarians. After controlling for demographics other than age, American Society of Anesthesiologists score, and medical comorbidities, octogenarians had higher 30-day odds of death (odds ratio [OR] = 6.12, P = .024), minor adverse events (OR = 2.97, P = .001), prolonged hospital length of stay (OR = 2.30, <0.001), nonhome discharge (OR = 4.50, P < .001), and readmission (OR = 1.72, P = .015), but did not experience increased odds of serious adverse events (OR = 1.07, P = .172) or return to the operating room (OR = 0.97, P = .881).

Conclusion

The present study found a statistically significant increase in several adverse events within 30 days of surgery for patients aged ≥80 years when compared with patients younger than 80 years. Namely, UKA in octogenarians was associated with significantly increased odds of short-term mortality, urinary tract infection, transfusion, prolonged hospital stay, and readmission.

Outpatient Simultaneous Bilateral Total Knee Arthroplasty: Is It Safe?

BACKGROUND

It is currently unknown if simultaneous bilateral total knee arthroplasty (si-BTKA) can also be safely performed in the outpatient setting. The primary aim of this study was to compare 30-day postoperative complication rates between outpatient and inpatient si-BTKA.

METHODS

Adults undergoing simultaneous bilateral total knee arthroplasty (si-BTKA) from 2015-2019 were queried using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Our primary analysis compared the rates of complications between outpatient si-BTKA and inpatient si-BTKA using bivariate comparisons and multivariable logistic regression of outpatient and inpatient cases controlling for differences in baseline demographics and comorbidities.

RESULTS

From 2015 to 2019, the utilization of outpatient si-BTKA increased from 0.6% to 10.5%. Outpatient si-BTKA were found to have significantly lower odds of any complication (OR = 0.49), minor complication (OR = 0.50), and postoperative transfusion (OR = 0.66) compared to inpatient cases. Outpatient si-BTKA also had a significantly shorter operative time.

CONCLUSION

Compared to inpatient si-BTKA, patients who undergo outpatient si-BTKA do not demonstrate increased rates of any complication, severe complications, and minor complications within 30-days postoperatively. Further insight is needed on the effect of outpatient si-BTKA on long-term outcomes.

Impact of enhanced recovery pathways on safety and efficacy of hip and knee arthroplasty: A systematic review and meta-analysis

BACKGROUND

Over the past decades, clinical pathways (CPs) for hip and knee arthroplasty have been strongly and continuously evolved based on scientific evidence and innovation.

AIM

The present systematic review, including meta-analysis, aimed to compare the safety and efficacy of enhanced recovery pathways (ERP) with regular pathways for patients with hip and/or knee arthroplasty.

METHODS

A literature search in healthcare databases (Embase, PubMed, Cochrane Library, CINAHL, and Web of Science) was conducted from inception up to June 2018. Relevant randomized controlled trials as well as observational studies comparing ERP, based on novel evidence, with regular or standard pathways, prescribing care as usual for hip and/or knee arthroplasty, were included. The effect of both CPs was assessed for (serious) adverse events [(S)AEs], readmission rate, length of hospital stay (LoS), clinician-derived clinical outcomes, patient reported outcome measures (PROMs), and financial benefits. If possible, a meta-analysis was performed. In case of considerable heterogeneity among studies, a qualitative analysis was performed.

RESULTS

Forty studies were eligible for data extraction, 34 in meta-analysis and 40 in qualitative analysis. The total sample size consisted of more than 2 million patients undergoing hip or knee arthroplasty, with a mean age of 66 years and with 60% of females. The methodological quality of the included studies ranged from average to good. The ERP had lower (S)AEs [relative risk (RR): 0.9, 95% confidence interval (CI): 0.8-1] and readmission rates (RR: 0.8, 95%CI: 0.7-1), and reduced LoS [median days 6.5 (0.3-9.5)], and showed similar or improved outcomes for functional recovery and PROMs compared to regular pathways. The analyses for readmission presented a statistically significant difference in the enhanced recovery pathway in favor of knee arthroplasties (P = 0.01). ERP were reported to be cost effective, and the cost reduction varied largely between studies (€109 and $20573). The overall outcomes of all studies reported using Grading of Recommendation, Assessment, Development and Evaluation, presented moderate or high quality of evidence.

CONCLUSION

This study showed that implementation of ERP resulted in improved clinical and patient related outcomes compared to regular pathways in hip and knee arthroplasty, with a potential reduction of costs.

Ambulatory Single-level Posterior Cervical Foraminotomy for Cervical Radiculopathy: A Propensity-matched Analysis of Complication Rates

STUDY DESIGN

Retrospective cohort comparison study.

OBJECTIVE

The aim was to compare perioperative complications and 30-day readmission between ambulatory and inpatient posterior cervical foraminotomy (PCF) in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database.

SUMMARY OF BACKGROUND DATA

Single-level PCF for cervical radiculopathy is increasingly being performed as an ambulatory procedure. Despite this increase, there is a lack of published literature documenting the safety of ambulatory PCF.

MATERIALS AND METHODS

Patients who underwent PCF (through laminotomy or laminectomy) were identified in the 2005-2018 NSQIP database. Ambulatory procedures were defined as cases that had hospital length of stay=0 days. Inpatient procedures were defined as cases that had length of stay=1-4 days. Patient characteristics, comorbidities, and procedural variables (laminotomy or laminectomy performed) were compared between the 2 cohorts. Propensity score matched comparisons were then performed for postoperative complications and 30-day readmissions between the 2 groups.

RESULTS

In total, 795 ambulatory and 1789 inpatient single-level PCF cases were identified. After matching, there were 795 ambulatory and 795 inpatient cases. Statistical analysis after propensity score matching revealed no significant difference in individual complications including 30-day readmission, thromboembolic events, wound complications, and reoperation, or aggregated complications between ambulatory versus matched inpatient procedures. Overall 30-day readmissions after ambulatory single-level PCF were noted for 2.46% of the study population, and the most common reasons were surgical site infections (46%) and pain control (15%).

CONCLUSIONS

The perioperative outcomes assessed in this study support the conclusion that single-level PCF for cervical radiculopathy can be performed for correctly selected patients in the ambulatory setting without increased rates of 30-day perioperative complications or readmissions compared with inpatient procedures.

LEVEL OF EVIDENCE

Level III.

Outpatient Shoulder Arthroplasty-A Systematic Review

Objective

Recent reports have shown that outpatient shoulder arthroplasty (SA) may be a safe alternative to inpatient management in appropriately selected patients. The purpose was to review the literature reporting on outpatient SA.

Methods

A systematic review of publications on outpatient SA was performed. Included publications discussed patients who were discharged on the same calendar day or within 23 hours from surgery. Articles were categorized by discussions on complications, readmissions, and safety, patient selection, pain management strategies, cost effectiveness, and patient and surgeon satisfaction.

Results

Twenty-six articles were included. Patients undergoing outpatient SA were younger and with a lower BMI than those undergoing inpatient SA. Larger database studies reported more medical complications for patients undergoing inpatient compared to outpatient SA. Articles on pain management strategies discussed both single shot and continuous interscalene blocks with similar outcomes. Both patients and surgeons reported high levels of satisfaction following outpatient SA, and cost analysis studies demonstrated significant cost savings for outpatient SA.

Conclusion

In appropriately selected patients, outpatient SA can be a safe, cost-saving alternative to inpatient care and may lead to high satisfaction of both patients and physicians, though further studies are needed to clarify appropriate utilization of outpatient SA.

On the generalizability of same-day partial knee replacement surgery-A non-selective interventional study evaluating efficacy, patient satisfaction, and safety in a public hospital setting

PURPOSE

Programs referred to as Fast-Track/Rapid Recovery/Enhanced Recovery After Surgery have proven both effective and safe in joint replacement surgery, to the degree where same-day discharge (SDD) has been attempted in carefully selected cases at specialized outpatient units. Therefore, the primary aim of this study was to evaluate a same-day surgery protocol regarding safety using the minor partial knee replacement (PKR) procedure by non-selectively recruiting patients at a public hospital for one consecutive year.

METHODS

33 unselected PKR cases were included in this open clinical trial. The inclusion/exclusion criteria were solely based on logistics, as all the procedures were medial PKRs, designated the first morning slots, and performed by one single-surgeon. Strict postoperative criteria based on vital parameters, urinary function, bleeding, and mobilization had to be met before discharge was considered. SDD rate, patient satisfaction, number of outpatient visits, adverse events and readmissions within 90 days were evaluated. A predetermined subgroup analysis was also conducted where patients <80 yrs. and with an American Society of Anesthesiologists (ASA) classification <III was compared with those aged ≥80 yrs. and/or ASA class ≥III.

RESULTS

29 of 33 (88%) successfully achieved SDD. In a univariate comparison, 100% of the patients <80 yrs. and ASA class <III achieved SDD, whereas a corresponding 43% applied for those aged ≥80 yrs. and/or ASA class ≥III (p = 0.001). A 93% overall satisfaction rate was reached. Only 8% extra outpatient visits were required, all occurring within the first 2 weeks (well in line with routine practice.) One plausible transient ischemic attack and one readmission caused by a penetrating trauma not affecting the knee were identified, both of which happened 10 weeks after surgery. No adverse events or readmissions occurred within the first 48 hours of surgery.

CONCLUSION

When following strict criteria for discharge, same-day partial knee replacement surgery may be both feasible and safe, even without preselection of patients.

The patient perspective, experience and satisfaction of day case unicompartmental knee arthroplasty: A short-term mixed-methods study

BACKGROUND

Day case unicompartmental knee arthroplasty (UKA) is increasingly being performed worldwide. When performed in the appropriate patient, day case UKA has been demonstrated to be safe, cost effective and improve resource allocation. Limited evidence highlights increased patient satisfaction of day case UKA when compared with inpatient UKA. A detailed study of the patient perspective, experience and satisfaction following day case UKA has not been described before.

METHODS

A retrospective case series review of 21 consecutive patients (19 unilateral, 2 bilateral) undergoing day case UKA in an elective orthopaedic centre was undertaken. A qualitative and quantitative patient assessment of the day case UKA experience was administered. A five-point Likert scale satisfaction questionnaire, Oxford Knee Score (OKS) and open-ended interview was undertaken. The qualitative responses underwent thematic analysis.

RESULTS

One hundred percent of patients expressed satisfaction (76.2% completely satisfied, 33.8% moderately satisfied) with day case UKA. The majority of patients (90.5%) reported that if they had to undergo UKA again they would prefer a day case over an inpatient procedure. Patients consider surgical outcome, physiotherapy provision, discharge planning, postoperative medications and follow up as key aspects of day case UKA care. One patient was re-admitted following discharge.

CONCLUSIONS

The present study demonstrates a high level of patient satisfaction with day case UKA. The results reported herein are subject to the study limitations of sample size, recall bias and inclusion criteria. We recommend that the themes identified by patients are addressed through a multidisciplinary approach with well-defined clinical pathways for a high-quality patient-centred experience.

Fewer Adverse Events Following Outpatient Compared with Inpatient Unicompartmental Knee Arthroplasty

BACKGROUND

Unicompartmental knee arthroplasty (UKA) is a common procedure for unicompartmental knee arthritis, often resulting in pain relief and improved function. The demand for total knee arthroplasty in the U.S. is projected to grow 85% between 2014 and 2030, and the volume of UKA procedures is growing 3 to 6 times faster than that of total knee arthroplasty. The purpose of the present study was to examine the safety of outpatient and inpatient UKA and to investigate changes over time as outpatient procedures were performed more frequently.

METHODS

Patients who underwent UKA from 2005 to 2018 as part of the National Surgical Quality Improvement Program were identified. Patients were divided into an early cohort (5,555 patients from 2005 to 2015) and late cohort (5,627 patients from 2016 to 2018). Outpatient status was defined as discharge on the day of surgery. Adverse events within 30 days postoperatively were compared, with adjustment for baseline characteristics with use of standard multivariate regression and propensity-score-matching techniques.

RESULTS

Among the 5,555 cases in the early cohort, the rate of surgical-site infection was lower for inpatient (0.84%) compared with outpatient UKA (1.69%; adjusted relative risk [RR] for inpatient, 0.5; 95% confidence interval [CI], 0.2 to 1.0; p = 0.045); no other significant differences were identified. Among the 5,627 cases in the late cohort, inpatient UKA had higher rates of any complication (2.53% compared with 0.95% for outpatient UKA; adjusted RR for inpatient, 2.5; 95% CI, 1.4 to 4.3; p = 0.001) and readmission (1.81% compared with 0.88% for outpatient UKA; adjusted RR for inpatient, 2.0; 95% CI, 1.1 to 3.5; p = 0.023). In the propensity-score-matched comparison for the late cohort, inpatient UKA had a higher rate of any complication (RR for inpatient, 2.0; 95% CI, 1.0 to 4.0; p = 0.049) and return to the operating room (RR for inpatient, 4.3; 95% CI, 1.4 to 12.6; p = 0.009). Although the rate of readmission was almost twice as high among inpatients (1.67% compared with 0.84% for outpatients; RR for inpatient, 2.0; 95% CI, 1.0 to 4.1; p = 0.059), this difference did not reach significance with the sample size studied. There was a significant reduction in the overall rate of complications over time (3.44% in the early cohort compared with 2.11% in the late cohort; adjusted RR for late cohort, 0.7; 95% CI, 0.5 to 0.8; p = 0.001), with a more than fourfold reduction among outpatients (3.95% in the early cohort compared with 0.95% in the late cohort; adjusted RR for late cohort, 0.3; 95% CI, 0.1 to 0.5; p < 0.001).

CONCLUSIONS

Outpatient UKA was associated with a lower risk of complications compared with inpatient UKA when contemporary data are examined. We identified a dramatic reduction in complications across the early and late cohorts, suggesting an improvement in quality over time, with the largest improvements seen among outpatients. This shift may represent changes in patient selection or improvements in perioperative protocols.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Trends in Utilization of Total and Unicompartmental Knee Arthroplasty in the United States

Total knee replacement (TKR) and unicompartmental knee replacement (UKR) are successful procedures for patients with knee arthritis. While strict criteria were proposed early on for UKR, some surgeons have expanded these indications to include younger and heavier patients. The purpose of this study is to analyze trends in usage of TKR and UKR in the United States. This retrospective study analyzed an insurance administrative dataset. Patients who underwent primary TKR and UKR were identified via current procedural terminology codes. Information on incidence, obesity, use of computer navigation, and surgical setting were collected. We analyzed 7,194 UKRs and 128,849 TKRs performed from 2007 to 2016. Prevalence of obesity in both groups increased over the study period. Utilization of computer navigation increased for UKR but declined for TKR. The rate of outpatient procedures significantly increased for UKR but remained constant for TKR. Both TKR and UKR are being performed at increasing rates and on heavier patients. The use of computer navigation and outpatient surgical setting is increasing for UKR but not for TKR. Knowledge of these trends is important for surgeons and policy-makers to help inform surgical indications and resource allocation.

Day-case unicompartmental knee arthroplasty: a literature review and development of a novel hospital pathway

INTRODUCTION

We have seen unparalleled changes in our healthcare systems globally as a result of the COVID-19 pandemic. As we strive to regenerate our full capacity elective services in order to contest the increasing demand for lower limb arthroplasty, this pandemic has allowed us a rare opportunity to revise and develop novel elective arthroplasty pathways intended to improve patient care and advance healthcare efficiency. We present an extensive evidence-based review of the approaches used to achieve day-case unicompartmental arthroplasty (UKA) as well as the development of a day-case UKA care pathway in a UK NHS institution based on the evidence provided in the literature.

METHODS

An extensive search of the literature was performed for articles that reported on readmission or complication rates ≥30 days postoperatively following day-case UKA.

FINDINGS

Fifteen manuscripts reporting the results of day-case UKA, defined as discharged on the same calendar day of surgery, were included in our review. Mean reported complication rates for day-case and inpatient UKA within the follow-up periods were 4.05% and 6.52%, respectively. Mean readmission rates were 2.71% and 4.36% for day-case and inpatient UKA, respectively. The mean rate of successful same-day discharge was 92.45%.

CONCLUSION

We introduce our institutional Elective Day Surgery Arthroplasty Pathway (EDSAP) founded upon the evidence presented in the literature. Stringent patient selection complimented by a well-defined day-case arthroplasty pathway is fundamental for successful commencement of day-case UKA in the NHS.

Similar 90-day outcomes among inpatient and outpatient arthroplasties : a single-surgeon matched cohort analysis

AIMS

The proportion of arthroplasties performed in the ambulatory setting has increased considerably. However, there are concerns whether same-day discharge may increase the risk of complications. The aim of this study was to compare 90-day outcomes between inpatient arthroplasties and outpatient arthroplasties performed at an ambulatory surgery centre (ASC), and determine whether there is a learning curve associated with performing athroplasties in an ASC.

METHODS

Among a single-surgeon cohort of 970 patients who underwent arthroplasty at an ASC, 854 (88.0%) were matched one-to-one with inpatients based on age, sex, American Society of Anesthesiologists (ASA) grade, BMI, and procedure (105 could not be adequately matched and 11 lacked 90-day follow-up). The cohort included 281 total hip arthroplasties (THAs) (32.9%), 267 unicompartmental knee arthroplasties (31.3%), 242 primary total knee arthroplasties (TKAs) (28.3%), 60 hip resurfacings (7.0%), two revision THAs (0.3%), and two revision TKAs (0.3%). Outcomes included readmissions, reoperations, visits to the emergency department, unplanned clinic visits, and complications.

RESULTS

The inpatient and outpatient groups were similar in all demographic variables, reflecting successful matching. The reoperation rate was 0.9% in both cohorts (p = 1.000). Rates of readmission (2.0% inpatient vs 1.6% outpatient), any complications (5.9% vs 5.6%), minor complications (4.2% vs 3.9%), visits to the emergency department (2.7% vs 1.4%), and unplanned clinic visits (5.7% vs 5.5%) were lower in the outpatient group but did not reach significance with the sample size studied. A learning curve may exist, as seen by significant reductions in the reoperation and overall complication rates among outpatient arthroplasties over time (p = 0.032 and p = 0.007, respectively), despite those in this group becoming significantly older and heavier (both p < 0.001) during the study period.

CONCLUSION

Arthroplasties performed at ASCs appear to be safe in appropriately selected patients, but may be associated with a learning curve as shown by the significant decrease in complication and reoperation rates during the study period. Cite this article: Bone Joint J 2021;103-B(7 Supple B):84-90.

Inpatient dermatology: Where are we headed? A nationwide population-based study of Spain from 2006 to 2016

BACKGROUND AND OBJECTIVES

Information about hospital admissions for skin diseases is restricted to studies describing admissions to single centers, to specific wards, or only for a few diagnoses, and there is no information about the outcomes between different wards. The aim of this research is to describe hospital admissions due to dermatological diseases.

PATIENTS AND METHODS

Cross-sectional study of hospital discharges at Spanish hospitals. Discharges were assumed to be the same as admissions.

RESULTS

519,440 discharges (1.1 % of total discharges) were identified. Most admissions (60.1 %) were done from emergency departments. Only 7 % of cases were admitted to dermatology wards. The most prevalent group was cellulitis and acute lymphangitis. Median age was 57 years, and men were more common. The median length of hospital stay was four days; 40,823 (7.9 %) cases required readmission. There were 13,558 (2.6 %) hospital deaths. After adjusted analysis (by age, sex and group of diagnosis), the OR of readmission was 1.49 (95 % CI: 1.42-1.57) times higher and length of stay was 0.22 (95 % CI: 0.15-0.29) days longer in non-dermatology wards (P < 0.0001). From 2006-2016, admissions to dermatology wards decreased 38 %, while in non-dermatology wards they increased 8 %.

CONCLUSIONS

A non-negligible number of patients require dermatological inpatient management. This is mainly provided by non-dermatologists. Some of our findings may indicate an improved overall care by dermatologists.

Economic Analysis and Clinical Outcomes of Short-Stay Versus Inpatient Total Ankle Replacement Surgery

BACKGROUND

We aimed to perform an economic analysis and compare the clinical outcomes between inpatient and short-stay designation total ankle replacement (TAR).

METHODS

We performed a retrospective study on 178 consecutive patients undergoing primary inpatient versus short-stay designation TAR during the 2016 and 2017 fiscal years. Patient demographics, concomitant procedures, perioperative complications, patient-reported outcomes, and perioperative costs were collected.

RESULTS

The mean age of our cohort was 62.5 ± 9.6 years (range, 30-88 years), with a significant difference in age (64.1 vs 58.5 years) (P = .005) and Charlson Comorbidity Index (3.3 ± 1.9 vs 2.3 ± 1.4; P = .002) for the inpatient and short-stay designation groups, respectively. At a mean follow-up of 29.6 ± 11.8 months (range, 12-52.3 months), there was no difference in complications between groups (P = .97). The inpatient designation TAR group had a worse baseline Short Musculoskeletal Functional Assessment (SMFA) function score (76.1; 95% CI, 70.5-81.6) than the short-stay designation TAR group (63.9; 95% CI, 52.5-75.3) while achieving similar final postoperative SMFA function scores for the inpatient (55.2; 95% CI, 51.1-59.2) and short-stay (56.2; 95% CI, 48.2-64.2) designation TAR groups (P > .05). However, the inpatient designation TAR group showed a significantly greater mean improvement in SMFA function score (20.9; 95% CI, 19.4-22.4) compared with the short-stay designation TAR group (7.7; 95% CI, 3.7-11.1) (P = .0442). The total direct cost was significantly higher for the inpatient designation group ($15 340) than the short-stay designation group ($13 002) (P < .001).

CONCLUSION

While inpatient designation TARs were more comorbid, short-stay designation TARs were associated with a 15.5% reduction in perioperative costs, comparable complication rates, and similar final postoperative patient-reported outcome scores compared with inpatient TARs.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Operative Fixation of Hip Fractures in Nonagenarians: Is It Safe?

BACKGROUND

With the shift in hip fracture epidemiology toward older individuals as well as the shift in demographics toward nonagenarians, it is important to understand the outcomes of treatment for these patients.

METHODS

Geriatric patients (≥65 years old) who underwent surgery for hip fracture were identified in the 2005-2017 National Surgical Quality Improvement Program database and stratified into 2 age groups: <90 and ≥90 years old (nonagenarians). Preoperative and procedural characteristics were compared. Multivariate regressions were used to compare risk for complications and 30-day readmissions. Risk factors for serious adverse events (SAEs) and 30-day mortality in nonagenarians were characterized.

RESULTS

This study included 51,327 <90 year olds and 15,798 nonagenarians. Overall rate of SAEs in nonagenarians was 19.89% while in <90 year olds was 14.80%. Multivariate analysis revealed higher risk for blood transfusion (relative risk [RR] = 1.21), death (RR = 1.74), pneumonia (RR = 1.24), and cardiac complications (RR = 1.33) in nonagenarians (all P < .001). Risk factors for SAEs in nonagenarians include American Society of Anesthesiologists ≥3, dependent functional status, admitted from nursing home/chronic/intermediate care, preoperative hypoalbuminemia, and male gender (all P < .05), but not time to surgery (P > .05). In fact, increased time to surgery in nonagenarians was associated with lower risk of 30-day mortality (RR = 0.90, P = .048).

CONCLUSION

Overall complication risk after hip fracture fixation in nonagenarians remains relatively low but higher than their younger counterparts. Interestingly, since time to surgery was not associated with adverse outcomes in nonagenarians, the commonly accepted 48-hour operative window may not be critical to this population. Additional time for preoperative medical optimization in this vulnerable population appears prudent.

Barriers to achieving same day discharge following unilateral unicompartmental knee arthroplasty

BACKGROUND

Evidence suggests that only a minority of unselected patients are able to achieve same day (SD) discharge following unilateral unicompartmental knee arthroplasty (UKA). However, many hospitals continue to classify UKA as an outpatient procedure, creating financial pressure to limit prolonged hospitalizations. To understand and address challenges that decrease patients' likelihood of achieving SD discharge, this study aimed to identify barriers commonly contributing to SD discharge failures with following a rapid discharge protocol (RDP).

METHODS

Retrospectively collected data from 158 unselected patients having undergone unilateral UKA between 2018 and 2019 were reviewed. All patients were treated using an established RPD with intended SD discharge.

RESULTS

Successful SD discharge was achieved by 84.2% of patient. Overall, those failing to achieve SD discharge were older (p < 0.001), more commonly female (p = 0.037), have multiple functional deficits (p < 0.05) and experience post-operative nausea (p < 0.001). Increased age, the use of an assisted device, and post-operative nausea accounted for 44.8% of the variability for patient not achieving SD discharge. The model was able to classify 95.7% of SD discharge and 38.1% of unsuccessful SD discharge patients, for an overall success rate of 85.1%.

CONCLUSIONS

The use of a well-developed, interdisciplinary RDP for unilateral UKA results in high SD discharge success in a community hospital setting. However, with 15.8% of patients still not able to achieve SD discharge, a more efficient RDP may include prioritizing patient scheduling, with lower priority given to older individuals requiring an assisted device, and changes to preventative and symptomatic treatment options for post-operative nausea.

Preoperative laboratory testing for total hip arthroplasty: Unnecessary tests or a helpful prognosticator

BACKGROUND

The last decade has seen increasing initiatives to improve health care delivery while decreasing financial expenditures, as particularly exemplified by the implementation of bundled payments for lower extremity arthroplasty, which hold the providers responsible for the both the quality and cost of these procedures. In this context, the utility of routine preoperative laboratory testing is unknown. The present study characterizes the associations, if any, between preoperative sodium, blood urea nitrogen (BUN), and creatinine values and the occurrence of general health adverse outcomes following total hip arthroplasty (THA).

METHODS

Patients undergoing primary THA were identified in the 2011-2015 National Surgical Quality Improvement Program. Cases with traumatic, oncologic, or infectious indications were excluded. Preoperative levels of sodium, BUN, and creatinine were tested for associations with perioperative adverse events and adverse hospital metrics using multivariate regressions that adjusted for patient baseline characteristics.

RESULTS

A total of 92,093 patients were included, of which 5.25% had an abnormal preoperative sodium level, 24.20% had an abnormal preoperative BUN level, and 11.95% had an abnormal preoperative creatinine level. Abnormal preoperative sodium levels (odds ratios: 1.23-1.50, p < 0.007) and creatinine levels (odds ratios: 1.27-1.55, p < 0.007) were associated with the occurrence of all studied adverse outcomes and abnormal preoperative BUN levels (odds ratios: 1.15-1.52, p < 0.007) were associated with the occurrence of all adverse outcomes except for hospital readmission.

CONCLUSIONS

Abnormal preoperative laboratory testing is significantly associated with adverse outcomes following THA, supporting the added value of laboratory evaluation of patients before elective arthroplasty procedures.

STUDY DESIGN

Clinical, Level III.

Preoperative High, as well as Low, Platelet Counts Correlate With Adverse Outcomes After Elective Total Hip Arthroplasty

Preoperative laboratory studies are often obtained as part of the workup for surgeries such as total hip arthroplasty (THA). An increasing need exists to be able to identify patients at risk for adverse outcomes. Thus, metrics that correlate with postoperative adverse events and readmissions are increasingly important to optimize patient care. The implications of varying abnormal platelet counts, especially on the high end of the spectrum, have yet to be assessed in large, multicenter patient populations. This study aims to risk stratify THA patients with varying preoperative platelet counts to address these questions. The purposes of this study were to (1) evaluate cutoffs for normal versus abnormal platelet counts for patients undergoing THA by using postoperative complications data and (2) assess the correlation of such values with readmission data using the National Surgical Quality Improvement Program database.

Why are patients still in hospital after fast-track, unilateral unicompartmental knee arthroplasty

Background and purpose - Previous studies have investigated risk factors related to prolonged length of stay following total knee arthroplasty (TKA), but little is known about specific factors resulting in continued hospitalization within the 1st postoperative days after unicompartmental knee arthroplasty (UKA). We investigated what specific factors prevent patients from being discharged on the day of surgery (DOS) and the first postoperative day (POD-1) following primary UKA in a fast-track setting.Patients and methods - We prospectively collected data on 100 consecutive and unselected medial UKA patients operated from December 2017 to May 2019. All patients were operated in a standardized fast-track setup with functional discharge criteria continuously evaluated from DOS and until discharge.Results - Median length of stay for the entire cohort was 1 day. 22% and 78% of all patients were discharged on DOS and POD-1, respectively. Lack of mobilization and pain separately delayed discharge in respectively 78% and 24% of patients on DOS. The main reasons for lack of mobilization were motor blockade (37%) and logistical factors (26%). For patients placed 1st or 2nd on the operating list, we estimate that the same-day discharge rate would increase to 55% and 40% respectively, assuming that pain and mobilization were successfully managed.Interpretation - One-fifth of unselected UKA patients operated in a standardized fast-track setup were discharged on DOS. Pain and lack of mobilization were the major reasons for continued hospitalization within the initial postoperative 24-48 hours. Strategies aimed at decreasing length of stay after UKA should strive to improve analgesia and postoperative mobilization.

Reimbursement and Complications in Outpatient vs Inpatient Unicompartmental Arthroplasty

BACKGROUND

Increasing utilization of unicompartmental knee arthroplasty (UKA) has driven a greater push for outpatient treatment and cost containment in the setting of bundled payments. The purpose of this study is to evaluate utilization trends of inpatient vs outpatient UKA, index episode and 90-day reimbursement, and any differences in medical or surgical complications.

METHODS

The PearlDiver database was employed to identify all inpatient and outpatient UKAs performed between 2007 and 2016 with 2-year follow-up. Patients were matched by age, gender, and Elixhauser Comorbidity Index. We tracked index procedure and global period reimbursement, 90-day medical and surgical complications, and 2-year surgical complications.

RESULTS

The reimbursement and utilization cohort included 3181 outpatient and 5490 inpatient UKAs. Outpatient UKA and overall utilization of UKA increased over the study period. Mean index reimbursement of inpatient UKA was $2486.16 higher per procedure (P < .001) while mean global period reimbursement was $2782.13 higher per inpatient procedure (P < .001). Ninety-day medical complications including postoperative anemia (P < .001), transfusion (P = .024), and arrhythmia (P = .004) were more common with inpatient UKAs, whereas surgical wound complications (P = .001) and operative debridement (P = .028) were more common among outpatient UKAs. Outpatient UKA was not associated with an increased risk of periprosthetic joint infection (P > .05), aseptic loosening (P > .05), or revision surgery (P > .05) when compared to inpatient UKA.

CONCLUSION

Outpatient UKA utilization is increasing and is associated with decreased reimbursement compared to inpatient UKA without increased risk of major medical complications, although it is associated with increased risk of wound complication and need for operative debridement at 90 days.

High, As Well As Low, Preoperative Platelet Counts Correlate With Adverse Outcomes After Elective Posterior Lumbar Surgery

STUDY DESIGN

Retrospective cohort study of prospectively collected data.

OBJECTIVE

Assess correlation between preoperative platelet counts and postoperative adverse events after elective posterior lumbar surgery procedures.

SUMMARY OF BACKGROUND DATA

Preoperative low platelet counts have been correlated with adverse outcomes after posterior lumbar surgery. Nonetheless, the effect of varying platelet counts has not been studied in detail for a large patient population, especially on the high end of the platelet spectrum.

METHODS

Patients who underwent elective posterior lumbar surgery were identified in the 2011 to 2016 National Surgical Quality Improvement Program database. Preoperative platelet counts were considered relative to 30-day perioperative adverse outcomes. Patients were classified into platelet categories based on determining upper and lower bounds on when the adverse outcomes crossed a relative risk of 1.5. Univariate and multivariate analyses compared 30-day postoperative complications, readmissions, operative time, and hospital length of stay between those with low, normal, and high platelet counts.

RESULTS

In total, 137,709 posterior lumbar surgery patients were identified. Using the relative risk threshold of 1.5 for the occurrence of any adverse event, patients were divided into abnormally low (≤140,000/mL) and abnormally high (≥447,000/mL) platelet cohorts. The abnormally low and high platelet groups were associated with higher rates of any, major, minor adverse events, transfusion, and longer hospital length of stay. Furthermore, the abnormally low platelet counts were associated with a higher risk of readmissions.

CONCLUSION

The data-based cut-offs for abnormally high and low platelet counts closely mirrored those found in literature. Based on these definitions, abnormally high and low preoperative platelet counts were associated with adverse outcomes after elective posterior lumbar surgery. These findings facilitate risk stratification and suggest targeted consideration for patients with high, as well as low, preoperative platelet counts.

LEVEL OF EVIDENCE

3.

Safety and Cost-Effectiveness of Outpatient Unicompartmental Knee Arthroplasty in the Ambulatory Surgery Center: A Matched Cohort Study

Using an age- and comorbidity-matched cohort, we compared patients who underwent unicompartmental knee arthroplasty in an ambulatory surgery center with those who underwent the procedure in a traditional hospital inpatient setting. Postoperatively, the ambulatory surgery center cohort had fewer major complications than the inpatient cohort. No ambulatory surgery center patients required acute hospital admission and none had major complications. Four major complications occurred in the inpatient cohort. There was no difference in complication rates. Our results suggest that outpatient unicompartmental knee arthroplasty in a freestanding ambulatory surgery center is a safe and reasonable alternative to the traditional inpatient hospital setting.

Incidence and safety profile of outpatient unicompartmental knee arthroplasty

BACKGROUND

Outpatient surgery is an increasingly attractive option for patients undergoing procedures with established, acceptable risk profiles. Benefits of outpatient surgery include cost savings, enhanced patient experience and improved resource allocation at busy hospitals. The purpose of this study was to compare 90-day complication and readmission rates for patients undergoing unicompartmental knee arthroplasty (UKA) in the outpatient as opposed to the inpatient setting.

METHODS

Patients who underwent UKA (CPT code 27446) between 2007 and 2016 were retrospectively selected from a national private insurance database. Patients were defined as ambulatory if their coded location of procedure was in an ambulatory surgery center or as an in-hospital outpatient. Postoperative complications were identified using the Reportable Center for Medicare Services (CMS) Complication Measures. Risks of complications were compared between the inpatient and outpatient cohorts using multivariate logistic regression controlling for age, gender, and comorbidities.

RESULTS

2600 patients undergoing ambulatory UKA and 5084 patients undergoing inpatient UKA were identified. The percentage of UKA procedures performed on an outpatient basis significantly increased over the course of the study (14.5% to 58.1%, p < 0.001). After adjusting for age, gender, and comorbidities, ambulatory surgery was found to be associated with a decreased risk of postoperative transfusion (OR 0.28; p < 0.001) and pneumonia (OR 0.23; p = 0.008) and there was a trend towards decreased 90-day readmission risk (OR = 0.83; p = 0.062).

CONCLUSION

Ambulatory discharge following UKA is increasing in popularity, does not increase risk for perioperative complications or readmission, and may even portend a safer post-operative course.

Safety of Outpatient Single-level Cervical Total Disc Replacement: A Propensity-Matched Multi-institutional Study

STUDY DESIGN

A retrospective cohort comparison study.

OBJECTIVE

The aim of this study was to investigate the perioperative adverse event profile of cervical total disc replacement (CTDR) performed as an outpatient relative to inpatient procedure.

SUMMARY OF BACKGROUND DATA

Recent reimbursement changes and a push for safe reductions in hospital stay have resulted in increased interest in performing CTDRs in the outpatient setting. However, there has been a paucity of studies investigating the safety of outpatient CTDR procedures, despite increasing frequency.

METHODS

Patients who underwent single-level CTDR were identified in the 2005 to 2016 National Surgical Quality Improvement Program database. Outpatient versus inpatient procedure status was defined by length of stay, with outpatient being less than 1 day. Patient baseline characteristics and comorbidities were compared between the two groups. Propensity score matched comparisons were then performed for 30-day perioperative complications and readmissions between the two cohorts. In addition, perioperative outcomes of outpatient single-level CTDR versus matched outpatient single-level anterior cervical discectomy and fusion (ACDF) cases were compared.

RESULTS

In total, 373 outpatient and 1612 inpatient single-level CTDR procedures were identified. After propensity score matching was performed to control for potential confounders, statistical analysis revealed no significant difference in perioperative complications between outpatient versus matched inpatient CTDR. Notably, the rate of readmissions was not different between the two groups. In addition, there was no difference in rates of perioperative adverse events between outpatient single-level CTDR versus matched outpatient single-level ACDF.

CONCLUSION

The perioperative outcomes evaluated in the current study support the conclusion that, for appropriately selected patients, single-level CTDR can be safely performed in the outpatient setting without increased rates of 30-day perioperative complications or readmissions compared with inpatient CTDR or outpatient single-level ACDF.

LEVEL OF EVIDENCE

3.

Cardiac Complications Related to Spine Surgery: Timing, Risk Factors, and Clinical Effect

INTRODUCTION

Large cohort studies evaluating cardiac complications in patients undergoing spine surgery are lacking. The purpose of this study was to determine the incidence, timing, risk factors, and effect of cardiac complications in spine surgery by using a national database, the American College of Surgeons National Surgical Quality Improvement Program.

METHODS

Patients who underwent spine surgery in the 2005 to 2012 National Surgical Quality Improvement Program database were identified. The primary outcome was an occurrence of cardiac arrest or myocardial infarction during the operation or the 30-day postoperative period. Risk factors for development of cardiac complications were identified using multivariate regression. The postoperative length of stay, 30-day readmission, and mortality were compared between patients who did and did not experience a cardiac complication.

RESULTS

A total of 30,339 patients who underwent spine surgery were identified. The incidence of cardiac complications was 0.34% (95% confidence interval [CI], 0.27% to 0.40%). Of the cases in which a cardiac complication developed, 30% were diagnosed after discharge. Risk factors for the development of cardiac complications were greater age (most notably ≥80 years, relative risk [RR] = 5.53; 95% CI = 2.28 to 13.43; P < 0.001), insulin-dependent diabetes (RR = 2.58; 95% CI = 1.51 to 4.41; P = 0.002), preoperative anemia (RR = 2.46; 95% CI = 1.62 to 3.76; P < 0.001), and history of cardiac disorders and treatments (RR = 1.88; 95% CI = 1.16 to 3.07; P = 0.011). Development of a cardiac complication before discharge was associated with a greater length of stay (7.9 versus 2.6 days; P < 0.001), and a cardiac complication after discharge was associated with increased 30-day readmission (RR = 12.32; 95% CI = 8.17 to 18.59; P < 0.001). Development of a cardiac complication any time during the operation or 30-day postoperative period was associated with increased mortality (RR = 113.83; 95% CI = 58.72 to 220.68; P < 0.001).

DISCUSSION

Perioperative cardiac complications were diagnosed in approximately 1 in 300 patients undergoing spine surgery. High-risk patients should be medically optimized and closely monitored through the perioperative period.

LEVEL OF EVIDENCE

Level III.

Elective Total Shoulder Arthroplasty in Octogenarians: A Safe Procedure

INTRODUCTION

There has been a lack of studies investigating the perioperative course of total shoulder arthroplasty (TSA) performed in the increasingly octogenarian (≥80 years old) population in a large sample size. The purpose of this study was to compare perioperative complications between primary TSA performed in octogenarians and that performed in younger populations (<70 and 70 to 79 years old) from the National Surgical Quality Improvement Program database.

METHODS

Patients who underwent primary TSA between January 2005 and December 2015 were identified from the National Surgical Quality Improvement Program database and stratified into three age groups: <70, 70 to 79, and ≥80 years old. Patient characteristics and comorbidities were compared between the three groups. Propensity score-matched comparisons were then performed for length of hospital stay, 30-day perioperative complications, and readmissions. Risk factors and reasons for readmission in the octogenarians were characterized.

RESULTS

This study included 3,007 patients who were <70 years old, 2,155 patients who were 70 to 79 years old, and 900 octogenarian patients. Statistical analysis was carried out after matching for propensity score. While no significant differences in perioperative complications were observed between the octogenarians and 70- to 79-year-olds, significantly higher rates of readmission (4.2% versus 1.7%; P = 0.002), pneumonia (1.1% versus 0.0%; P = 0.002), and urinary tract infection (1.8% versus 0.2%; P = 0.001) were found in the octogenarians compared with <70-year-olds. In addition, the octogenarians also had a slightly longer length of hospital stay compared with the younger populations (0.6 days longer than <70-year-olds and 0.4 days longer than 70- to 79-year-olds; both P < 0.001).

CONCLUSION

These data suggest that primary TSA can safely be considered for octogenarians with only mildly increased morbidities. However, greater preoperative optimization or post-discharge care for octogenarians may be warranted to reduce the rates of readmission.

Is Discharge Within a Day of Total Knee Arthroplasty Safe in the Octogenarian Population?

BACKGROUND

Reduced hospital stay programs for total knee arthroplasty (TKA) are being implemented in order to increase patient satisfaction and reduce healthcare costs. Although elderly patients are often included in these pathways, there have been limited data on whether older patients can safely be discharged within a day after TKA. The purpose of this study is to compare perioperative complications following primary TKA with ≤1 day in the hospital in patients aged ≥80 compared to <80 years old in the National Surgical Quality Improvement Program database.

METHODS

Patients who underwent primary TKA with hospital length of stay ≤1 day were identified in the 2005-2016 National Surgical Quality Improvement Program database. These patients were separated into 2 age groups: <80 and ≥80 years old. Preoperative and procedural characteristics were compared. Multivariate regressions were used to compare risk for perioperative adverse events and readmission. Independent risk factors for serious adverse events following such TKAs were identified.

RESULTS

In total, 17,191 (<80 year olds) and 1005 (≥80 year olds) cases were identified. Of these patients, 1750 cases were discharged the same day. Multivariate analysis revealed only higher risk for 30-day readmission and nonhome discharge in ≥80 compared to <80 year olds. Notably, the octogenarians had a significantly higher rate of nonsurgical site-related readmissions. Independent risk factors for serious adverse events include only American Society of Anesthesiologists score ≥3 and not patient age.

CONCLUSION

These data suggest that, although octogenarians can safely be discharged in ≤1 day, greater postdischarge care may be warranted to reduce the rate of nonsurgical site-related readmissions.

Comparative Analysis of Short-Term Postoperative Complications in Outpatient Versus Inpatient Total Ankle Arthroplasty: A Database Study

Ankle arthritis is a potentially debilitating disease, with approximately 50,000 cases diagnosed annually. One treatment option for these patients is total ankle arthroplasty (TAA). This procedure has historically been performed in the inpatient setting with a 1-2-night postoperative hospital stay. Outpatient surgeries are gaining popularity due to their cost effectiveness, decreased length of hospital stay, and convenience. Therefore it is important to evaluate the safety of specific procedures in the outpatient setting compared with the inpatient setting. This study evaluated the complication rates in inpatient versus outpatient TAA. It analyzed data from the National Surgical Quality Improvement Program for 591 patients who received TAA. Postoperative complication rates were compared between 66 outpatients and 535 inpatients. Frequencies of the following complications were analyzed: wound complications, pneumonia, hematologic complications (pulmonary embolism and deep vein thrombosis), renal failure, stroke, and return to the operating room within 30 days. Unadjusted direct comparisons of the cohorts revealed higher complication rates in the inpatient cohort. Inpatients had higher rates of superficial surgical site infections, deep surgical site infections, number of organ/space surgical site infections, pneumonia occurrences, and return to the operating room, but these differences were not significant. These results showed no significant increase in complication rates in outpatients compared to inpatients. Our results suggest that inpatient and outpatient TAA show similar complication rates. This suggests that outpatient TAA is safe and may be a superior option for certain populations. Further investigation is warranted to verify these conclusions.

Outpatient elective posterior lumbar fusions appear to be safely considered for appropriately selected patients

BACKGROUND CONTEXT

There has been growing interest in performing posterior lumbar fusions (PLFs) in the outpatient setting to optimize patient satisfaction and reduce cost. Although still done in only a small percentage of cases, this has been more possible because of advances in surgical techniques and anesthesia. However, data on the perioperative course of outpatient compared with inpatient PLF in a large sample size are scarce.

PURPOSE

This study aimed to compare perioperative complications between outpatient and inpatient PLF in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database.

STUDY DESIGN/SETTING

A retrospective cohort comparison study was carried out.

PATIENT SAMPLE

Patients undergoing PLF with or without interbody fusion from the 2005 to 2015 NSQIP database comprised the sample.

OUTCOME MEASURES

Outcome measures were postoperative complications within 30 days and readmission within 30 days.

METHODS

Patients who underwent PLF with or without interbody fusion were identified in the 2005-2015 NSQIP database. Outpatient procedures were defined as cases that had hospital length of stay (LOS)=0 days, whereas inpatient procedures were defined as LOS=1-30 days. Patient characteristics, comorbidities, and procedural variables (inclusion of interbody fusion, instrumentation, and number of levels fused) were compared between the two cohorts. Propensity score-matched comparisons were then performed for postoperative complications and 30-day readmissions between the two groups.

RESULTS

The current study included 360 outpatient and 36,610 inpatient PLF cases. After propensity matching to control potential confounding factors, statistical analysis revealed no significant difference in postoperative adverse events other than significantly lower blood transfusions in the outpatient group (2.78% vs. 10.83%, p<.001). Notably, the rate of readmissions was not different between the groups.

CONCLUSIONS

Based on the lack of differences in rates of most perioperative complications and 30-day readmissions between the outpatient and inpatient cohorts, it seems that outpatient PLF may be appropriately considered for select patients. However, extremely careful patient selection should be exercised.

Incidence, Risk Factors, and Impact of Clostridium difficile Colitis After Spine Surgery: An Analysis of a National Database

STUDY DESIGN

A retrospective study of prospectively collected data.

OBJECTIVE

The aim of this study was to utilize a large national database with post-hospitalization follow-up data [National Surgical Quality Improvement Program (NSQIP)] to determine the incidence, risk factors, timing, and clinical impact of Clostridium difficile colitis in spine surgery patients.

SUMMARY OF BACKGROUND DATA

Recent literature has suggested an increased incidence of C. difficile infections. However, there has been a lack of large cohort studies defining the incidence and impact of C. difficile colitis in patients undergoing spine surgery.

METHODS

Patients who underwent spine surgical procedures in the 2015 NSQIP database were identified. The primary outcome was a diagnosis of C. difficile colitis within the 30-day postoperative period. Independent risk factors for development of C. difficile colitis were identified using multivariate regression. Postoperative length of stay and rate of 30-day readmission were compared between patients who did and did not develop C. difficile colitis.

RESULTS

A total of 23,981 patients who underwent spine surgical procedures were identified. The incidence of C. difficile colitis was approximately 0.11% [95% confidence interval (95% CI), 0.07-0.16]. Of the cases that developed C. difficile colitis, 70% were diagnosed postdischarge and 88% had not had a pre-existing infection diagnosed. Independent risk factors for the development of C. difficile colitis were combined anterior/posterior lumbar fusion procedures [odds ratio (OR) = 12.29, 95% CI = 2.22-68.13, P = 0.010], greater age (most notably ≥76 years old, OR = 10.31, 95% CI = 3.06-34.76, P < 0.001), hypoalbuminemia (OR = 6.40, 95% CI = 2.49-16.43, P < 0.001), and anemia (OR = 2.39, 95% CI = 1.13-5.05, P = 0.023). The development of C. difficile colitis was associated with greater length of stay (2.2 vs. 12.5 days; P < 0.001) and increased 30-day readmission (OR = 8.21, 95% CI = 3.14-21.45, P < 0.001).

CONCLUSION

C. difficile was diagnosed in 0.11% of patients undergoing spine surgery. The majority of these cases occurred after discharge and in patients not having prior infection diagnoses. High-risk patients should be monitored and targeted with preventative interventions accordingly.

LEVEL OF EVIDENCE

3.

Unicompartmental knee arthroplasty: Current indications, technical issues and results

An age younger than 60 years, a body weight of 180 lb (82 kg) or more, performing heavy work, having chondrocalcinosis and having exposed bone in the patellofemoral (PF) joint are not contraindications for unicompartmental knee arthroplasty (UKA).Severe wear of the lateral facet of the PF joint with bone loss and grooving is a contraindication for UKA.Medial UKA should only be performed in cases of severe osteoarthritis (OA) as shown in pre-operative X-rays, with medial bone-on-bone contact and a medial/lateral ratio of < 20%.The post-operative results of UKA are generally good. Medium-term and long-term studies have reported acceptable results at 10 years, with implant survival greater than 95% for UKAs performed for medial OA or osteonecrosis and for lateral UKA, especially when fixed-bearing implants are used.When all implant-related re-operations are considered, the 10-year survival rate is 94%, and the 15-year survival rate is 91%.Aseptic loosening is the principal failure mechanism in the first few years in mobile-bearing implants, whereas OA progression causes most failures in later years in fixed-bearing implants.The overall complication rate and the comprehensive re-operation rate are comparable in both mobile bearings and fixed bearings.The survival likelihood of the all-polyethylene UKA implant is similar to that of metal-backed modular designs for UKA.Notable cost savings of approximately 50% can be achieved with an outpatient UKA surgery protocol. Outpatient surgery for UKA is efficacious and safe, with satisfactory clinical results thus far. Cite this article: EFORT Open Rev 2018;3:363-373. DOI: 10.1302/2058-5241.3.170048.

How Common-and How Serious- Is Clostridium difficile Colitis After Geriatric Hip Fracture? Findings from the NSQIP Dataset

BACKGROUND

Patients with geriatric hip fractures may be at increased risk for postoperative Clostridium difficile colitis, which can cause severe morbidity and can influence hospital quality metrics. However, to our knowledge, no large database study has calculated the incidence of, factors associated with, and effect of C. difficile colitis on geriatric patients undergoing hip fracture surgery.

QUESTIONS/PURPOSES

To use a large national database with in-hospital and postdischarge data (National Surgical Quality Improvement Program [NSQIP®]) to (1) determine the incidence and timing of C. difficile colitis in geriatric patients who underwent surgery for hip fracture, (2) identify preoperative and postoperative factors associated with the development of C. difficile colitis in these patients, and (3) test for an association between C. difficile colitis and postoperative length of stay, 30-day readmission, and 30-day mortality.

PATIENTS AND METHODS

This is a retrospective study. Patients who were 65 years or older who underwent hip fracture surgery were identified in the 2015 NSQIP database. The primary outcome was a diagnosis of C. difficile colitis during the 30-day postoperative period. Preoperative and procedural factors were tested for association with the development of C. difficile colitis through a backward stepwise multivariate model. Perioperative antibiotic type and duration were not included in the model, as this information was not recorded in the NSQIP. The association between C. difficile colitis and postoperative length of stay, 30-day readmission, and 30-day mortality were tested through multivariate regressions, which adjusted for preoperative and procedural characteristics such as age, comorbidities, and surgical procedure. A total of 6928 patients who were 65 years or older and underwent hip fracture surgery were identified.

RESULTS

The incidence of postoperative C. difficile colitis was 1.05% (95% CI, 0.81%-1.29%; 73 of 6928 patients). Of patients who had C. difficile colitis develop, 64% (47 of 73 patients) were diagnosed postdischarge and 79% (58 of 73 patients) did not have a preceding infectious diagnosis. Preoperative factors identifiable before surgery that were associated with the development of C. difficile colitis included admission from any type of chronic care facility (versus admitted from home; relative risk [RR] = 1.98; 95% CI, 1.11-3.55; p = 0.027), current smoker within 1 year (RR = 1.95; 95% CI, 1.03-3.69; p = 0.041), and preoperative anemia (RR = 1.76; 95% CI, 1.07-2.92; p = 0.027). Patients who had pneumonia (RR = 2.58; 95% CI, 1.20-5.53; p = 0.015), sepsis (RR = 4.20; 95% CI, 1.27-13.82; p = 0.018), or "any infection" (RR = 2.26; 95% CI, 1.26-4.03; p = 0.006) develop after hip fracture were more likely to have C. difficile colitis develop. Development of C. difficile colitis was associated with greater postoperative length of stay (22 versus 5 days; p < 0.001), 30-day readmission (RR = 3.41; 95% CI, 2.17-5.36; p < 0.001), and 30-day mortality (15% [11 of 73 patients] versus 6% [439 of 6855 patients]; RR = 2.16; 95% CI, 1.22-3.80; p = 0.008).

CONCLUSIONS

C. difficile colitis is a serious infection after hip fracture surgery in geriatric patients that is associated with 15% mortality. Patients at high risk, such as those admitted from any type of chronic care facility, those who had preoperative anemia, and current smokers within 1 year, should be targeted with preventative measures. From previous studies, these measures include enforcing strict hand hygiene with soap and water (not alcohol sanitizers) if a provider is caring for patients at high risk and those who are C. difficile-positive. Further, other studies have shown that certain antibiotics, such as fluoroquinolones and cephalosporins, can predispose patients to C. difficile colitis. These medications perhaps should be avoided when prescribing prophylactic antibiotics or managing infections in patients at high risk. Future prospective studies should aim to determine the best prophylactic antibiotic regimens, probiotic formula, and discharge timing that minimize postoperative C. difficile colitis in patients with hip fractures.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Discrepancies in the Definition of "Outpatient" Surgeries and Their Effect on Study Outcomes Related to ACDF and Lumbar Discectomy Procedures: A Retrospective Analysis of 45,204 Cases

STUDY DESIGN

This is a retrospective study.

OBJECTIVE

To study the differences in definition of "inpatient" and "outpatient" [stated status vs. actual length of stay (LOS)], and the effect of defining populations based on the different definitions, for anterior cervical discectomy and fusion (ACDF) and lumbar discectomy procedures in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database.

SUMMARY OF BACKGROUND DATA

There has been an overall trend toward performing ACDF and lumbar discectomy in the outpatient setting. However, with the possibility of patients who underwent outpatient surgery staying overnight or longer at the hospital under "observation" status, the distinction of "inpatient" and "outpatient" is not clear.

MATERIALS AND METHODS

Patients who underwent ACDF or lumbar discectomy in the 2005-2014 ACS-NSQIP database were identified. Outpatient procedures were defined in 1 of 2 ways: either as being termed "outpatient" or hospital LOS=0. Differences in definitions were studied. Further, to evaluate the effect of the different definitions, 30-day outcomes were compared between "inpatient" and "outpatient" and between LOS>0 and LOS=0 for ACDF patients.

RESULTS

Of the 4123 "outpatient" ACDF patients, 919 had LOS=0, whereas 3204 had LOS>0. Of the 13,210 "inpatient" ACDF patients, 337 had LOS=0, whereas 12,873 had LOS>0. Of the 15,166 "outpatient" lumbar discectomy patients, 8968 had LOS=0, whereas 6198 had LOS>0. Of the 12,705 "inpatient" lumbar discectomy patients, 814 had LOS=0, whereas 11,891 had LOS>0. On multivariate analysis of ACDF patients, when comparing "inpatient" with "outpatient" and "LOS>0" with "LOS=0" there were differences in risks for adverse outcomes based on the definition of outpatient status.

CONCLUSIONS

When evaluating the ACS-NSQIP population, ACDF and lumbar discectomy procedures recorded as "outpatient" can be misleading and often did not correlate with same day discharge. These findings have significant impact on the interpretation of existing studies and define an area that needs clarification for future studies.

LEVEL OF EVIDENCE

Level 3.

Aseptic revision total hip arthroplasty in the elderly

Aims

The aim of this study was to compare the rate of perioperative complications following aseptic revision total hip arthroplasty (THA) in patients aged ≥ 80 years with that in those aged < 80 years, and to identify risk factors for the incidence of serious adverse events in those aged ≥ 80 years using a large validated national database.

Patients and Methods

Patients who underwent aseptic revision THA were identified in the 2005 to 2015 National Surgical Quality Improvement Program (NSQIP) database and stratified into two age groups: those aged < 80 years and those aged ≥ 80 years. Preoperative and procedural characteristics were compared. Multivariate regression analysis was used to compare the risk of postoperative complications and readmission. Risk factors for the development of a serious adverse event in those aged ≥ 80 years were characterized.

Results

The study included 7569 patients aged < 80 years and 1419 were aged ≥ 80 years. Multivariate analysis showed a higher risk of perioperative mortality, pneumonia, urinary tract infection and the requirement for a blood transfusion and an extended length of stay in those aged ≥ 80 years compared with those aged < 80 years. Independent risk factors for the development of a serious adverse event in those aged ≥ 80 years include an American Society of Anesthesiologists score of ≥ 3 and procedures performed under general anaesthesia.

Conclusion

Even after controlling for patient and procedural characteristics, aseptic revision THA is associated with greater risks in patients aged ≥ 80 years compared with younger patients. This is important for counselling and highlights the need for medical optimization in these vulnerable patients. Cite this article: Bone Joint J 2018;100-B:143–51.

Incidence, Risk Factors, and Impact of Clostridium difficile Colitis Following Primary Total Hip and Knee Arthroplasty

BACKGROUND

An improved understanding of Clostridium difficile is important as it is used as a measure of hospital quality and is associated with substantial morbidity. This study utilizes the National Surgical Quality Improvement Program to determine the incidence, timing, risk factors, and clinical implications of C difficile colitis in patients undergoing primary total hip or knee arthroplasty (THA or TKA).

METHODS

Patients who underwent primary THA or TKA as part of the 2015 National Surgical Quality Improvement Program were identified. The primary outcome was a diagnosis of C difficile colitis within the 30-day postoperative period. Risk factors for the development of C difficile colitis were identified using Poisson multivariate regression.

RESULTS

A total of 39,172 patients who underwent primary THA or TKA were identified. The incidence of C difficile colitis was 0.10% (95% confidence interval [CI] 0.07-0.13). Of the cases that developed C difficile colitis, 79% were diagnosed after discharge and 84% had not had a preceding infection diagnosed. Independent preoperative and procedural risk factors for the development of C difficile colitis were greater age (most notably ≥80 years old, relative risk [RR] 5.28, 95% CI 1.65-16.92, P = .008), dependent functional status (RR 4.05, 95% CI 1.44-11.36, P = .008), preoperative anemia (RR 2.52, 95% CI 1.28-4.97, P = .007), hypertension (RR 2.51, 95% CI 1.06-5.98, P = .037), and THA (vs TKA; RR 2.25, 95% CI 1.16-4.36, P = .017). Postoperative infectious risk factors were urinary tract infection (RR 10.66, 95% CI 3.77-30.12, P < .001), sepsis (RR 17.80, 95% CI 3.77-84.00, P < .001), and "any infection" (RR 6.60, 95% CI 2.66-16.34, P < .001).

CONCLUSION

High-risk patients identified in this study should be targeted with preventative interventions and have perioperative antibiotics judiciously managed.

Revision Total Knee Arthroplasty in Octogenarians: An Analysis of 957 Cases

BACKGROUND

The number of octogenarians undergoing revision total knee arthroplasty (TKA) is increasing. However, there has been a lack of studies investigating the perioperative course and safety of revision TKA performed in this potentially vulnerable population in a large patient population. The purpose of this study is to compare complications following revision TKA between octogenarians and 2 younger patient populations (<70 and 70-79 year olds).

METHODS

Patients who underwent revision TKA were identified in the 2005-2015 National Surgical Quality Improvement Program database and stratified into 3 age groups: <70, 70-79, and ≥80 years. Baseline preoperative and intraoperative characteristics were compared between the 3 groups. Propensity score matched comparisons were then performed for 30-day perioperative complications, length of hospital stay, and readmissions.

RESULTS

This study included 6523 (<70 years), 2509 (70-79 years), and 957 octogenarian patients who underwent revision TKA. After propensity matching, statistical analysis revealed only higher rates of blood transfusion and slightly longer length of stay in octogenarians compared to <70 year olds. Similarly, octogenarians had only higher rates of blood transfusion and slightly longer length of stay compared to 70-79 year olds. Notably, there were no differences in mortality or readmission between octogenarians compared to younger populations.

CONCLUSION

These data suggest that revision TKA can safely be considered for octogenarians with the observation of higher rates of blood transfusion and slightly longer length of stay compared to younger populations. Octogenarian patients need not be discouraged from revision TKA solely based on their advanced age.