Validation of a Discharge Risk Calculator for Rural Patients Following Total Joint Arthroplasty.

INTRODUCTION: As the volume of total joint arthroplasty (TJA) in the US continues to grow, new challenges surrounding appropriate discharge surface. Arthroplasty literature has demonstrated discharge disposition to post-acute care facilities carries major risks regarding the need for revision surgery, patient co-morbidities, and financial burden. To quantify, categorize, and mitigaterisks, a decision tool that uses preoperative patient variables has previously been published and validated using an urban patient population. The aim of our investigation was to validate the same predictive model using patients in a rural setting undergoing total knee arthroplasty (TKA) and total hip arthroplasty (THA). METHODS: All TKA and THA procedures that were performed between January 2012 and September 2022 at our institution were collected. A total of 9,477 cases (39.6% TKA, 60.4% THA) were included for the validation analysis. There were nine preoperative variables that were extracted in an automated fashion from the electronic medical record. Included patients were then run through the predictive model, generating a risk score representing that patient's differential risk of discharge to a skilled nursing facility (SNF) versus home. Overall accuracy, sensitivity and specificity were calculated after obtaining risk scores. RESULTS: Score cutoff equally maximizing sensitivity and specificity was 0.23, and the proportion of correct classifications by the predictive tool in this study population was found to be 0.723, with an area under the curve (AUC) of 0.788-both higher than previously published accuracy levels. With the threshold of 0.23, sensitivity and specificity were found to be 0.720 and 0.723, respectively. CONCLUSION: The risk calculator showed very good accuracy, sensitivity, and specificity in predicting discharge location for rural patients undergoing TKA and THA, with accuracy even higher than in urban populations. The model provides an easy-to-use interface, with automation representing a viable tool in helping with shared decision-making regarding postoperative discharge plans.

Association between radiographic soft-tissue thickness and increased length of stay, operative time, and infection rate after reverse shoulder arthroplasty.

BACKGROUND: Reverse shoulder arthroplasty (RSA) is a widely performed surgical procedure to address various shoulder pathologies. Several studies have suggested that radiographic soft-tissue thickness may play a role in predicting complications after orthopedic surgery, but there have been limited studies determining the use of radiographic soft-tissue thickness in RSA. The purpose of this study was to evaluate whether radiographic soft-tissue thickness could predict clinical outcomes after RSA and compare the predictive capabilities against body mass index (BMI). We hypothesized that increased radiographic shoulder soft-tissue thickness would be a strong predictor of operative time, length of stay (LOS), and infection in elective RSA. MATERIAL AND METHODS: A retrospective review of patients undergoing RSA at an academic institution was conducted. Preoperative radiographic images were evaluated including measurements of the radius from the humeral head center to the skin (HS), deltoid radius-to-humeral head radius ratio (DHR), deltoid size, and subcutaneous tissue size. Different correlation coefficients were used to analyze various types of relationships, and the strength of these associations was classified based on predefined boundaries. Subsequently, multivariable linear and logistic regressions were performed to determine whether HS, DHR, deltoid size, and subcutaneous tissue size could predict LOS, operative time, or infection while controlling for patient factors. RESULTS: HS was the most influential factor in predicting both operative time and LOS after RSA, with strong associations indicated by standardized ß coefficients of 0.234 for operative time and 0.432 for LOS. Subcutaneous tissue size, deltoid size, and DHR also showed stronger predictive values than BMI for both outcomes. In terms of prosthetic joint infection, HS, deltoid size, and DHR were significant predictors, with HS demonstrating the highest predictive power (Nagelkerke R2 = 0.44), whereas BMI did not show a statistically significant association with infection. Low event counts resulted in wide confidence intervals for odds ratios in the infection analysis. CONCLUSION: Greater shoulder soft-tissue thickness as measured with concentric circles on radiographs is a strong predictor of operative time, LOS, and postoperative infection in elective primary RSA patients.

A validated preoperative risk prediction tool for extended inpatient length of stay following anatomic or reverse total shoulder arthroplasty.

BACKGROUND: Recent work has shown inpatient length of stay (LOS) following shoulder arthroplasty to hold the second strongest association with overall cost (after implant cost itself). In particular, a preoperative understanding for the patients at risk of extended inpatient stays (≥3 days) can allow for counseling, optimization, and anticipating postoperative adverse events. METHODS: A multicenter retrospective review was performed of 5410 anatomic (52%) and reverse (48%) total shoulder arthroplasties done at 2 large, tertiary referral health systems. The primary outcome was extended inpatient LOS of at least 3 days, and over 40 preoperative sociodemographic and comorbidity factors were tested for their predictive ability in a multivariable logistic regression model based on the patient cohort from institution 1 (derivation, N = 1773). External validation was performed using the patient cohort from institution 2 (validation, N = 3637), including area under the receiver operator characteristic curve (AUC), sensitivity, specificity, and positive and negative predictive values. RESULTS: A total of 814 patients, including 318 patients (18%) in the derivation cohort and 496 patients (14%) in the validation cohort, experienced an extended inpatient LOS of at least 3 days. Four hundred forty-five (55%) were discharged to a skilled nursing or rehabilitation facility. Following parameter selection, a multivariable logistic regression model based on the derivation cohort (institution 1) demonstrated excellent preliminary accuracy (AUC: 0.826), with minimal decrease in accuracy under external validation when tested against the patients from institution 2 (AUC: 0.816). The predictive model was composed of only preoperative factors, in descending predictive importance as follows: age, marital status, fracture case, ASA (American Society of Anesthesiologists) score, paralysis, electrolyte disorder, body mass index, gender, neurologic disease, coagulation deficiency, diabetes, chronic pulmonary disease, peripheral vascular disease, alcohol dependence, psychoses, smoking status, and revision case. CONCLUSION: A freely-available, preoperative online clinical decision tool for extended inpatient LOS (≥ 3 days) after shoulder arthroplasty reaches excellent predictive accuracy under external validation. As a result, this tool merits consideration for clinical implementation, as many risk factors are potentially modifiable as part of a preoperative optimization strategy.

A Validated Pre-operative Risk Prediction Tool for Extended Inpatient Length of Stay Following Primary Total Hip or Knee Arthroplasty.

BACKGROUND: As value-based reimbursement models mature, understanding the potential trade-off between inpatient lengths of stay and complications or need for costly postacute care becomes more pressing. Understanding and predicting a patient's expected baseline length of stay may help providers understand how best to decide optimal discharge timing for high-risk total joint arthroplasty (TJA) patients. METHODS: A retrospective review was conducted of 37,406 primary total hip (17,134, 46%) and knee (20,272, 54%) arthroplasties performed at two high-volume, geographically diverse, tertiary health systems during the study period. Patients were stratified by 3 binary outcomes for extended inpatient length of stay: 72 + hours (29%), 4 + days (11%), or 5 + days (5%). The predictive ability of over 50 sociodemographic/comorbidity variables was tested. Multivariable logistic regression models were created using institution #1 (derivation), with accuracy tested using the cohort from institution #2 (validation). RESULTS: During the study period, patients underwent an extended length of stay with a decreasing frequency over time, with privately insured patients having a significantly shorter length of stay relative to those with Medicare (1.9 versus 2.3 days, P < .0001). Extended stay patients also had significantly higher 90-day readmission rates (P < .0001), even when excluding those discharged to postacute care (P < .01). Multivariable logistic regression models created from the training cohort demonstrated excellent accuracy (area under the curve (AUC): 0.755, 0.783, 0.810) and performed well under external validation (AUC: 0.719, 0.743, 0.763). Many important variables were common to all 3 models, including age, sex, American Society of Anesthesiologists (ASA) score, body mass index, marital status, bilateral case, insurance type, and 13 comorbidities. DISCUSSION: An online, freely available, preoperative clinical decision tool accurately predicts risk of extended inpatient length of stay after TJA. Many risk factors are potentially modifiable, and these validated tools may help guide clinicians in preoperative patient counseling, medical optimization, and understanding optimal discharge timing.

Transitioning to Outpatient Shoulder Arthroplasty: Safety, Efficiency, and Cost in a Diverse Payer Mix.

Outpatient shoulder arthroplasty presents potential clinical benefits but also risk without perioperative optimization. Length of stay depends largely on surgeon preferences, and a large single-surgeon cohort may provide insight into optimal strategies and costs for outpatient shoulder arthroplasty. A single-surgeon cohort of 472 anatomic and reverse shoulder arthroplasties performed between 2017 and 2020 was retrospectively reviewed. Cases were stratified by those who did or did not undergo same-day discharge. The 90-day readmission, discharge to post-acute care, cost, and 45 patient/case factors were examined. Two hundred fifty (53%) underwent same-day discharge, with the proportion of outpatient cases increasing over time to nearly 80%, with no significant difference in 90-day readmissions. Revision cases often underwent same-day discharge, whereas fractures were typically admitted. The cost was significantly higher for inpatients, with implants accounting for 52%. Surgeons may safely transition a substantial proportion of shoulder arthroplasties to same-day discharge with some reassurance regarding cost savings and 90-day readmissions. (Journal of Surgical Orthopaedic Advances 32(4):263-269, 2023).

Trends in outcomes following aseptic revision shoulder arthroplasty.

PURPOSE: As the incidence of anatomic and reverse total shoulder arthroplasty (TSA, RSA) increases, revision procedures will also increase with a corresponding need for counseling patients regarding outcomes. We hypothesized that different revision categories would have different complication profiles depending on both the indication as well as the nature of the prior hardware. METHODS: A retrospective review of 1773 cases performed at a single tertiary health system utilized case postings and diagnoses to identify revision shoulder arthroplasty cases. Revisions were classified based on the prior hardware present, with basic demographics and other perioperative and postoperative outcomes recorded within the limits of available follow-up. RESULTS: 166 surgical cases involving revision of prior shoulder arthroplasty metal hardware were identified with an average follow-up of 1.0 years. Immediate perioperative outcomes of revision cases were similar relative to the companion cohort of 1607 primary cases. 137 cases (83%) required no further revision surgery, while 19 cases (11%) underwent aseptic revision, and 10 cases (6%) were revised for periprosthetic infection. RSA hardware revised to another RSA had the highest repeat revision rate relative to the other revision categories (32% vs < 14%). CONCLUSIONS: Revision of reverse shoulder arthroplasty to a repeat reverse has the highest rate of subsequent all-cause revision, and these repeat revisions often occurred for periprosthetic infection. Despite a relatively high long-term complication rate following revision shoulder arthroplasty, immediate perioperative outcomes remain similar to primary cases, providing some preliminary evidence for policymakers considering inclusion in future value-based care models. LEVEL OF EVIDENCE: Level III Treatment Study.

Is Advanced Imaging to Assess Rotator Cuff Integrity Before Shoulder Arthroplasty Cost-effective? A Decision Modeling Study.

BACKGROUND: Shoulder arthroplasty is increasingly performed for patients with symptoms of glenohumeral arthritis. Advanced imaging may be used to assess the integrity of the rotator cuff preoperatively because a deficient rotator cuff may be an indication for reverse shoulder arthroplasty (RSA) rather than anatomic total shoulder arthroplasty (TSA). However, the cost-effectiveness of advanced imaging in this setting has not been analyzed. QUESTIONS/PURPOSES: In this cost-effectiveness modeling study of TSA, all patients underwent history and physical examination, radiography, and CT, and we compared (1) no further advanced imaging, (2) selective MRI, (3) MRI for all, (4) selective ultrasound, and (5) ultrasound for all. METHODS: A simple chain decision model was constructed with a base-case 65-year-old patient with a 7% probability of a large-to-massive rotator cuff tear and a follow-up of 5 years. Strategies were compared using the incremental cost-effectiveness ratio (ICER) with a willingness to pay of both USD 50,000 and 100,000 per quality-adjusted life year (QALY) used, in accordance with the Second Panel on Cost-Effectiveness in Health and Medicine. Diagnostic test sensitivity and specificity were extracted from published systematic reviews and meta-analyses, and patient utilities were obtained using the Cost-Effectiveness Analysis Registry from the Center for the Evaluation of Value and Risk in Health. Final patient states were categorized as either inappropriate or appropriate based on the actual rotator cuff integrity and type of arthroplasty performed. Additionally, to evaluate the real-world impact of intraoperative determination of rotator cuff status, a secondary analysis was performed where all patients indicated for TSA underwent intraoperative rotator cuff examination to determine appropriate implant selection. RESULTS: Selective MRI (ICER of USD 40,964) and MRI for all (ICER of USD 79,182/QALY) were the most cost-effective advanced imaging strategies at a willingness to pay (WTP) of USD 50,000/QALY gained and 100,000/QALY gained, respectively. Overall, quality-adjusted life years gained by advanced soft tissue imaging were minimal: 0.04 quality-adjusted life years gained for MRI for all. Secondary analysis accounting for the ability of the surgeon to alter the treatment plan based on intraoperative rotator cuff evaluation resulted in the no further advanced imaging strategy as the dominant strategy as it was the least costly (USD 23,038 ± 2259) and achieved the greatest health utility (0.99 ± 0.05). The sensitivity analysis found the original model was the most sensitive to the probability of a rotator cuff tear in the population, with the value of advanced imaging increasing as the prevalence increased (rotator cuff tear prevalence greater than 12% makes MRI for all cost-effective at a WTP of USD 50,000/QALY). CONCLUSION: In the case of diagnostic ambiguity based on physical exam, radiographs, and CT alone, having both TSA and RSA available in the operating room appears more cost-effective than obtaining advanced soft tissue imaging preoperatively. However, performing selective MRI to assess rotator cuff integrity to indicate RSA or TSA is cost-effective if surgical preparedness, patient expectations, and implant availability preclude the ability to switch implants intraoperatively. LEVEL OF EVIDENCE: Level III, economic and decision analysis.

Simple preoperative radiographic and computed tomography measurements predict adequate bone quality for stemless total shoulder arthroplasty.

INTRODUCTION: Although there is increased utilization of stemless humeral implants in anatomic total shoulder arthroplasty (TSA), there are inadequate objective metrics to evaluate bone quality sufficient for fixation. Our goals are to: (1) compare patient characteristics in patients who had plans for stemless TSA but received stemmed TSA due to intraoperative assessments and (2) propose threshold values of bone density, using the deltoid tuberosity index (DTI) and proximal humerus Hounsfield units (HU), on preoperative X-ray and computed tomography (CT) to allow for preoperative determination of adequate bone stock for stemless TSA. METHODS: This is an observational study conducted at an academic institution from 2019 to 2021, including consecutive primary TSAs templated to undergo stemless TSA based on 3-dimensional CT preoperative plans. Final implant selection was determined by intraoperative assessment of bone quality. Preoperative X-ray and CT images were assessed to obtain DTI and proximal humeral bone density in HU, respectively. A receiver operating characteristic curve was used to analyze the potential of preoperative X-ray and CT to classify patients as candidates for stemless TSA. RESULTS: A total of 61 planned stemless TSAs were included, with 56 (91.8%) undergoing stemless TSA and 5 (8.2%) undergoing stemmed TSA after intraoperative assessment determined that the bone quality was inadequate for stemless fixation. There were no significant differences between the 2 groups in terms of gender (P = .640), body mass index (P = .296), and race (P = .580). The stem cohort was significantly older (mean age 69 ± 12 years vs. 59 ± 10 years, P = .029), had significantly lower DTI (1.45 ± 0.13 vs. 1.68 ± 0.18, P = .007), and had significantly less proximal humeral HU (-1.4 ± 17.7 vs. 78.8 ± 52.4, P = .001). The receiver operating characteristic curve for DTI had an area under the curve (AUC) of 0.86, and bone density in HU had an AUC of 0.98 in its ability to distinguish patients who underwent stemless TSA vs. short-stem TSA. A threshold cutoff of 1.41 for DTI resulted in a sensitivity of 98% and a specificity of 60%, and a cutoff value of 14.4 HU resulted in a sensitivity of 95% and a specificity of 100%. CONCLUSIONS: Older age, lower DTI, and less proximal humeral bone density in HU were associated with the requirement to switch from stemless to short-stem humeral fixation in primary TSA. Preoperative DTI had good ability (AUC of 0.86) and preoperative HU had excellent ability (AUC of 0.98) to categorize patients as appropriate for stemless TSA. This can help surgeons adequately plan humeral fixation using standard preoperative imaging data.

Influence of medical comorbidity and surgical indication on total elbow arthroplasty cost of care.

BACKGROUND: Movement toward providing value-based musculoskeletal care requires understanding the cost associated with surgical care as well as the drivers of these costs. The aim of this study was to investigate the effect of common medical comorbidities and specific total elbow arthroplasty (TEA) indications on reimbursement costs throughout the 90-day TEA episode of care. The secondary aim was to identify the drivers of these costs. METHODS: Administrative health claims for patients who underwent orthopedic intervention between 2010 and 2020 were queried using specific disease classification and procedural terminology codes from a commercially available national database of 53 million patients. Patients with commercial insurance were divided into various cohorts determined by different surgical indications and medical comorbidities. The reimbursement costs of the surgical encounter, 89-day postoperative period, and total 90-day period in each cohort were evaluated. The cost drivers for the 89-day postoperative period were also determined. Analyses were performed using descriptive statistics and the Kruskal-Wallis test for comparison. RESULTS: A total of 378 patients who underwent TEA were identified. The mean reimbursement cost of the surgical encounter ($13,393 ± $8314) did not differ significantly based on patient factors. The mean reimbursement cost of the 89-day postoperative period ($4232 ± $2343) differed significantly when stratified by surgical indication (P < .0001) or by medical comorbidity (P < .0001). The indication of rheumatoid arthritis ($4864 ± $1136) and the comorbidity of chronic kidney disease ($5873 ± $1165) had the most expensive postoperative period. In addition, the total 90-day reimbursement cost ($16,982 ± $4132) differed significantly when stratified by surgical indication (P = .00083) or by medical comorbidity (P < .0001), with the indication of acute fracture ($18,870 ± $3971) and the comorbidity of chronic pulmonary disease ($19,194 ± $3829) showing the highest total 90-day cost. Inpatient costs related to readmissions represented 38% of the total reimbursement cost. The overall readmission rate was 5.0%, and the mean readmission cost was $16,296. CONCLUSION: TEA reimbursements are significantly influenced by surgical indications and medical comorbidities during the postoperative period and the total 90-day episode of care. As the United States transitions to delivering value-based health care, the need for surgeons and policy makers to understand treatment costs associated with different patient-level factors will expand.

Heterogeneity of pain-related psychological distress in patients seeking care for shoulder pathology.

BACKGROUND: Psychological distress is associated with disability and quality of life for patients with shoulder pain. However, uncertainty around heterogeneity of psychological distress has limited the adoption of shoulder care models that address psychological characteristics. In a cohort of patients with shoulder pain, our study sought to (1) describe the prevalence of various subtypes of psychological distress; (2) evaluate associations between psychological distress and self-reported shoulder pain, disability, and function; and (3) determine differences in psychological distress profiles between patients receiving nonoperative vs. operative treatment. METHODS: The sample included 277 patients who were evaluated in clinic by a shoulder surgeon and completed the Optimal Screening for Prediction of Referral and Outcome Yellow Flag Assessment Tool (OSPRO-YF) from 2019 to 2021. This tool categorizes maladaptive and adaptive psychological traits, and the number of yellow flags (YFs) ranges from 0 to 11, with higher YF counts indicating higher pain-related psychological distress. Operative and nonoperative cohorts were compared using χ2 test and Student t test. Linear regression was used to evaluate the association between pain, disability, and YFs, whereas Poisson regression evaluated the association between operative treatment and psychological distress. K-means cluster analysis was performed to propose potential psychological distress phenotypes. RESULTS: Two hundred fifty-one patients (91%) had at least 1 YF on the OSPRO-YF tool, with a mean number of 6 ± 3.5 YFs. YFs in unhelpful coping (85%) and helpful coping domains (78%) were most prevalent. The number of YFs was significantly associated with baseline shoulder pain (P < .001), Single Assessment Numeric Evaluation (P < .001), and American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (P < .001) scores. Comparing operative and nonoperative cohorts, the operative cohort had a significantly higher mean number of YFs (6.5 vs. 5.6, P = .035), presence of any YF (94.3% vs. 85.7%, P = .015), and presence of YFs within the unhelpful coping domain (91.8% vs. 75.6%, P < .001). Three phenotypes were described, corresponding to low, moderate, and severe psychological distress (P < .001), with females (P = .037) and smokers (P = .018) associated with higher psychological distress phenotypes. CONCLUSIONS: YFs, particularly within the unhelpful coping and helpful coping domains, were highly prevalent in a cohort of patients presenting to a shoulder surgeon's clinic. Additionally, operative patients were found to have a significantly higher rate of YFs across multiple dimensions of psychological distress. These findings stress the importance of routine attentiveness to multiple dimensions of pain-related psychological distress in shoulder populations, which can provide an opportunity to reinforce healthy interpretation of pain while minimizing distress in appropriately identified patients.

Characteristics and risk factors for 90-day readmission following shoulder arthroplasty.

BACKGROUND: Anatomic total shoulder arthroplasty (TSA) and reverse TSA are the standard of care for end-stage shoulder arthritis. Advancements in implant design, perioperative management, and patient selection have allowed shorter inpatient admissions. Unplanned readmissions remain a significant complication. Identification of risk factors for readmission is prudent as physicians and payers prepare for the adoption of bundled care reimbursement models. The purpose of this study was to identify characteristics and risk factors associated with readmission following shoulder arthroplasty using a large, bi-institutional cohort. METHODS: A total of 2805 anatomic TSAs and 2605 reverse TSAs drawn from 2 geographically diverse, tertiary health systems were examined for unplanned inpatient readmissions within 90 days following the index operation (primary outcome). Forty preoperative patient sociodemographic and comorbidity factors were tested for their significance using both univariable and multivariable logistic regression models, and backward stepwise elimination selected for the most important associations for 90-day readmission. Readmissions were characterized as either medical or surgical, and subgroup analysis was performed. A short length of stay (discharge by postoperative day 1) and discharge to a rehabilitation or skilled nursing facility were also examined as secondary outcomes. Parameters associated with increased readmission risk were included in a predictive model. RESULTS: Within 90 days of surgery, 175 patients (3.2%) experienced an unanticipated readmission, with no significant difference between institutions (P = .447). There were more readmissions for surgical complications than for medical complications (62.9% vs. 37.1%, P < .001). Patients discharged to a rehabilitation or skilled nursing facility were significantly more likely to be readmitted (13.1% vs. 8.8%, P = .049), but a short inpatient length of stay was not associated with an increased rate of 90-day readmission (42.9% vs. 41.3%, P = .684). Parameter selection based on predictive ability resulted in a multivariable logistic regression model composed of 16 preoperative patient factors, including reverse TSA, revision surgery, right-sided surgery, and various comorbidities. The area under the receiver operator characteristic curve for this multivariable logistic regression model was 0.716. CONCLUSION: Risk factors for unplanned 90-day readmission following shoulder arthroplasty include reverse shoulder arthroplasty, surgery for revision and fracture, and right-sided surgery. Additionally, there are several modifiable and nonmodifiable risk factors that can be used to ascertain a patient's readmission probability. A shorter inpatient stay is not associated with an increased risk of readmission, whereas discharge to post-acute care facilities does impose a greater risk of readmission. As scrutiny around health care cost increases, identifying and addressing risk factors for readmission following shoulder arthroplasty will become increasingly important.

Short stay after shoulder arthroplasty does not increase 90-day readmissions in Medicare patients compared with privately insured patients.

BACKGROUND: As of January 1, 2021, total shoulder arthroplasty was removed from the Medicare inpatient-only list, reflecting a growing belief in the potential merits of same-day discharge regardless of insurance type. It is yet unknown whether Medicare populations, which frequently have more severe comorbidity burdens, would experience higher complication rates relative to privately insured patients, who are often younger with fewer comorbidities. Given the limited number of true outpatient cohorts available to study, discharge at least by postoperative day 1 may serve as a useful proxy for true same-day discharge, and we hypothesized that these Medicare patients would have increased 90-day readmission rates compared with their privately insured counterparts. METHODS: Data on 4723 total shoulder arthroplasties (anatomic in 2459 and reverse in 2264) from 2 large, geographically diverse health systems in patients having either Medicare or private insurance were collected. The unplanned 90-day readmission rate was the primary outcome, and patients were stratified into those who were discharged at least by postoperative day 1 (short inpatient stay) and those who were not. Patients with private insurance (n = 1845) were directly compared with those with Medicare (n = 2878), whereas cohorts of workers' compensation (n = 198) and Medicaid (n = 58) patients were analyzed separately. Forty preoperative variables were examined to compare overall health burden, with the χ2 and Wilcoxon rank sum tests used to test for statistical significance. RESULTS: Medicare patients undergoing short-stay shoulder arthroplasty were not significantly more likely than those with private insurance to experience an unplanned 90-day readmission (3.6% vs. 2.5%, P = .14). This similarity existed despite a substantially worse comorbidity burden in the Medicare population (P < .05 for 26 of 40 factors). Furthermore, a short inpatient stay did not result in an increased 90-day readmission rate in either Medicare patients (3.6% vs. 3.4%, P = .77) or their privately insured counterparts (2.5% vs. 2.4%, P = .92). Notably, when the analysis was restricted to a single insurance type, readmission rates were significantly higher for reverse shoulder arthroplasty compared with total shoulder arthroplasty (P < .001 for both), but when the analysis was restricted to a single procedure (anatomic or reverse), readmission rates were similar between Medicare and privately insured patients, whether undergoing a short or extended length of stay. CONCLUSIONS: Despite a substantially more severe comorbidity profile, Medicare patients undergoing short-stay shoulder arthroplasty did not experience a significantly higher rate of unplanned 90-day readmission relative to privately insured patients. A higher incidence of reverse shoulder arthroplasty in Medicare patients does increase their overall readmission rate, but a similar increase also appears in privately-insured patients undergoing a reverse indicating that Medicare populations may be similarly appropriate for accelerated-care pathways.

Perioperative pain control represents the primary concern for patients considering outpatient shoulder arthroplasty: a survey-based study.

BACKGROUND: Outpatient (OP) total shoulder arthroplasty (TSA) with same-day discharge can now be performed safely in appropriately selected patients. Patient knowledge and perspectives regarding OP TSA are yet unknown and such information may inform surgeon decision-making and provide a framework for addressing patient concerns. The goal of this study was to understand and quantify patient knowledge of and concerns for OP TSA, with a working hypothesis that majority of patients are unaware of OP TSA as a realistic option and that their primary concern would be postoperative pain control. METHODS: This was a retrospective cohort study at a tertiary care academic medical center including patients who underwent anatomic or reverse shoulder arthroplasty and completed an OP TSA expectations questionnaire/survey. This survey was provided preoperatively and included demographic factors, self-rated health evaluation, and perioperative expectations. Surveys evaluated whether patients undergoing TSA had any prior awareness of OP TSA and evaluated their primary concern with same-day discharge. Secondary questions included an assessment of patient expectations of outcomes of outpatient vs. inpatient surgery as well as their expected length of inpatient stay. RESULTS: A total of 122 patients who underwent anatomic and reverse shoulder arthroplasty completed the questionnaire and comprised the study cohort. Fifty-two (42.6%) of the patients were unaware that OP TSA was an option, and 26 (50%) of these were comfortable with the idea of OP TSA. Comfort with OP TSA was significantly associated with higher subjective patient-reported health status. Fifty-eight patients (47.5%) expected that following TSA they would require <24 hours of in-hospital postoperative care. The primary concern for patients considering OP TSA was postoperative pain control, endorsed by 44.3% of patients, compared with 13.1% of patients stating this would be their primary concern if admitted as an inpatient postoperatively. Pain control being a primary concern was significantly different between those considering outpatient vs. inpatient TSA. Most patients anticipated that OP shoulder arthroplasty would lead to a better (36%) or comparable (53%) outcome, whereas only 11% had concerns that it would lead to a worse outcome. CONCLUSION: Expanding OP TSA crucially depends on awareness and education. Perceived ability to control pain is an important concern. Patients may benefit from preoperative counseling, including emphasizing a comprehensive postoperative pain management strategy.

Appropriate patient selection for outpatient shoulder arthroplasty: a risk prediction tool.

BACKGROUND: The transition from inpatient to outpatient shoulder arthroplasty critically depends on appropriate patient selection, both to ensure safety and to counsel patients preoperatively regarding individualized risk. Cost and patient demand for same-day discharge have encouraged this transition, and a validated predictive tool may help decrease surgeon liability for complications and help select patients appropriate for same-day discharge. We hypothesized that an accurate predictive model could be created for short inpatient length of stay (discharge at least by postoperative day 1), potentially serving as a useful proxy for identifying patients appropriate for true outpatient shoulder arthroplasty. METHODS: A multicenter cohort of 5410 shoulder arthroplasties (2805 anatomic and 2605 reverse shoulder arthroplasties) from 2 geographically diverse, high-volume health systems was reviewed. Short inpatient stay was the primary outcome, defined as discharge on either postoperative day 0 or 1, and 49 patient outcomes and factors including the Elixhauser Comorbidity Index, sociodemographic factors, and intraoperative parameters were examined as candidate predictors for a short stay. Factors surviving parameter selection were incorporated into a multivariable logistic regression model, which underwent internal validation using 10,000 bootstrapped samples. RESULTS: In total, 2238 patients (41.4%) were discharged at least by postoperative day 1, with no difference in rates of 90-day readmission (3.5% vs. 3.3%, P = .774) between cohorts with a short length of stay and an extended length of stay (discharge after postoperative day 1). A multivariable logistic regression model demonstrated high accuracy (area under the receiver operator characteristic curve, 0.762) for discharge by postoperative day 1 and was composed of 13 variables: surgery duration, age, sex, electrolyte disorder, marital status, American Society of Anesthesiologists score, paralysis, diabetes, neurologic disease, peripheral vascular disease, pulmonary circulation disease, cardiac arrhythmia, and coagulation deficiency. The percentage cutoff maximizing sensitivity and specificity was calculated to be 47%. Internal validation showed minimal loss of accuracy after bias correction for overfitting, and the predictive model was incorporated into a freely available online tool to facilitate easy clinical use. CONCLUSIONS: A risk prediction tool for short inpatient length of stay after shoulder arthroplasty reaches very good accuracy despite requiring only 13 variables and was derived from an underlying database with broad geographic diversity in the largest institutional shoulder arthroplasty cohort published to date. Short inpatient length of stay may serve as a proxy for identifying patients appropriate for same-day discharge, although perioperative care decisions should always be made on an individualized and holistic basis.

A validated preoperative risk prediction tool for discharge to skilled nursing or rehabilitation facility following anatomic or reverse shoulder arthroplasty.

BACKGROUND: As bundled payment models continue to spread, understanding the primary drivers of cost excess helps providers avoid penalties and ensure equal health care access. Recent work has shown discharge to rehabilitation and skilled nursing facilities (SNFs) to be a primary cost driver in total joint arthroplasty, and an accurate preoperative risk calculator for shoulder arthroplasty would not only help counsel patients in clinic during shared decision-making conversations but also identify high-risk individuals who may benefit from preoperative optimization and discharge planning. METHODS: Anatomic and reverse total shoulder arthroplasty cohorts from 2 geographically diverse, high-volume centers were reviewed, including 1773 cases from institution 1 (56% anatomic) and 3637 from institution 2 (50% anatomic). The predictive ability of a variety of candidate variables for discharge to SNF/rehabilitation was tested, including case type, sociodemographic factors, and the 30 Elixhauser comorbidities. Variables surviving parameter selection were incorporated into a multivariable logistic regression model built from institution 1's cohort, with accuracy then validated using institution 2's cohort. RESULTS: A total of 485 (9%) shoulder arthroplasties overall were discharged to post-acute care (anatomic: 6%, reverse: 14%, P < .0001), and these patients had significantly higher rates of unplanned 90-day readmission (5% vs. 3%, P = .0492). Cases performed for preoperative fracture were more likely to require post-acute care (13% vs. 3%, P < .0001), whereas revision cases were not (10% vs. 10%, P = .8015). A multivariable logistic regression model derived from the institution 1 cohort demonstrated excellent preliminary accuracy (area under the receiver operating characteristic curve [AUC]: 0.87), requiring only 11 preoperative variables (in order of importance): age, marital status, fracture, neurologic disease, paralysis, American Society of Anesthesiologists physical status, gender, electrolyte disorder, chronic pulmonary disease, diabetes, and coagulation deficiency. This model performed exceptionally well during external validation using the institution 2 cohort (AUC: 0.84), and to facilitate convenient use was incorporated into a freely available, online prediction tool. A model built using the combined cohort demonstrated even higher accuracy (AUC: 0.89). CONCLUSIONS: This validated preoperative clinical decision tool reaches excellent predictive accuracy for discharge to SNF/rehabilitation following shoulder arthroplasty, providing a vital tool for both patient counseling and preoperative discharge planning. Further, model parameters should form the basis for reimbursement legislation adjusting for patient comorbidities, ensuring no disparities in access arise for at-risk populations.

Why Do Patients Undergoing Extremity Prosthetic Reconstruction for Metastatic Disease Get Readmitted?

BACKGROUND: Orthopedic oncology patients are particularly susceptible to increased readmission rates and poor surgical outcomes, yet little is known about readmission rates. The goal of this study is to identify factors independently associated with 90-day readmission for patients undergoing oncologic resection and subsequent prosthetic reconstruction for metastatic disease of the hip and knee. METHODS: This is a retrospective comparative cohort study of all patients treated from 2013 to 2019 at a single tertiary care referral institution who underwent endoprosthetic reconstruction by an orthopedic oncologist for metastatic disease of the extremities. The primary outcome measure was unplanned 90-day readmission. RESULTS: We identified 112 patients undergoing 127 endoprosthetic reconstruction surgeries. Metastatic disease was most commonly from renal (26.8%), lung (23.6%), and breast (13.4%) cancer. The most common type of skeletal reconstruction performed was simple arthroplasty (54%). There were 43 readmissions overall (33.9%). When controlling for confounding factors, body mass index >40, insurance status, peripheral vascular disease, and longer hospital length of stay were independently associated with risk of readmission (P ≤ .05). CONCLUSION: Readmission rates for endoprosthetic reconstructions for metastatic disease are high. Although predicting readmission remains challenging, risk stratification presents a viable option for helping minimize unplanned readmissions. LEVEL OF EVIDENCE: III.

Malnutrition in elective shoulder arthroplasty: a multi-institutional retrospective study of preoperative albumin and adverse outcomes.

BACKGROUND: Malnutrition is associated with poor postoperative outcomes after knee, hip, and spine surgery. However, whether albumin labs should be part of the routine preoperative workup for shoulder arthroplasty remains understudied. This study investigated the role of preoperative albumin levels in predicting common postoperative adverse outcomes in patients undergoing shoulder arthroplasty. METHODS: All shoulder arthroplasty cases performed at 2 tertiary referral centers between July 2013 and May 2019 (institution 1) and between June 2007 and Feb 2020 (institution 2) were reviewed. A total of 421 primary and 71 revision elective shoulder arthroplasty cases had preoperative albumin levels recorded. Common demographic variables and relevant Elixhauser comorbidities were pulled. Outcomes gathered included extended (>3 days) postoperative inpatient length of stay (eLOS), 90-day readmission, and discharge to rehab or skilled nursing facility (SNF). RESULTS: The prevalence of malnutrition (albumin <3.5 g/dL) was higher in the revision group compared with the primary group (36.6% vs. 19.5%, P = .001). Reverse shoulder arthroplasty (P = .013) and increasing American Society of Anesthesiologists score (P = .016) were identified as independent risk factors for malnutrition in the primary group. In the revision group, liver disease was associated with malnutrition (P = .046). Malnourished primary shoulder arthroplasty patients had an increased incidence of eLOS (26.8% vs. 13.6%, P = .003) and discharge to rehab/SNF (18.3% vs. 10.3%, P = .045). On univariable analysis, low albumin had an odds ratio (OR) of 2.34 for eLOS (P = .004), which retained significance in a multivariable model including age, American Society of Anesthesiologists score, sex, and body mass index (OR 2.11, P = .03). On univariable analysis, low albumin had an OR of 1.94 for discharge to SNF/rehab (P = .048), but this did not reach significance in the multivariable model. Among revisions, malnourished patients had an increased incidence of eLOS (30.8% vs. 6.7%, P = .014) and discharge to rehab/SNF (26.9% vs. 4.4%, P = .010). In both the primary and revision groups, there was no difference in 90-day readmission rate between patients with low or normal albumin. CONCLUSION: Malnutrition is more prevalent among revision shoulder arthroplasty patients compared with those undergoing a primary procedure. Primary shoulder arthroplasty patients with low preoperative albumin levels have an increased risk of eLOS and may have an increased need for postacute care. Low albumin was not associated with a risk of 90-day readmissions. Albumin level merits further investigation in large, prospective cohorts to clearly define its role in preoperative risk stratification.

A Preoperative Risk Prediction Tool for Discharge to a Skilled Nursing or Rehabilitation Facility After Total Joint Arthroplasty.

BACKGROUND: Discharge to rehabilitation or a skilled nursing facility (SNF) after total joint arthroplasty remains a primary driver of cost excess for bundled payments. An accurate preoperative risk prediction tool would help providers and health systems identify and modulate perioperative care for higher risk individuals and serve as a vital tool in preoperative clinic as part of shared decision-making regarding the risks/benefits of surgery. METHODS: A total of 10,155 primary total knee (5,570, 55%) and hip (4,585, 45%) arthroplasties performed between June 2013 and January 2018 at a single institution were reviewed. The predictive ability of 45 variables for discharge location (SNF/rehab vs home) was tested, including preoperative sociodemographic factors, intraoperative metrics, postoperative labs, as well as 30 Elixhauser comorbidities. Parameters surviving selection were included in a multivariable logistic regression model, which was calibrated using 20,000 bootstrapped samples. RESULTS: A total of 1786 (17.6%) cases were discharged to a SNF/rehab, and a multivariable logistic regression model demonstrated excellent predictive accuracy (area under the receiver operator characteristic curve: 0.824) despite requiring only 9 preoperative variables: age, partner status, the American Society of Anesthesiologists score, body mass index, gender, neurologic disease, electrolyte disorder, paralysis, and pulmonary circulation disorder. Notably, this model was independent of surgery (knee vs hip). Internal validation showed no loss of accuracy (area under the receiver operator characteristic curve: 0.8216, mean squared error: 0.0004) after bias correction for overfitting, and the model was incorporated into a readily available, online prediction tool for easy clinical use. CONCLUSION: This convenient, interactive tool for estimating likelihood of discharge to a SNF/rehab achieves excellent accuracy using exclusively preoperative factors. These should form the basis for improved reimbursement legislation adjusting for patient risk, ensuring no disparities in access arise for vulnerable populations. LEVEL OF EVIDENCE: III.

Medicaid Insurance Correlates With Increased Resource Utilization Following Total Hip Arthroplasty.

BACKGROUND: With increased restraints and efforts to contain costs in total hip arthroplasty (THA), an emphasis has been placed on risk stratification. The purpose of this study was to determine whether Medicaid patients have increased resource utilization (including 90-day emergency department [ED] visits and readmissions) compared to Medicare or commercial insurance carriers. The study hypothesized that the Medicaid population would represent a high-risk cohort with increased resource utilization. METHODS: The institutional database was retrospectively queried for primary THAs from 2013 to 2017 based on Current Procedural Terminology codes and patients undergoing revision surgery were excluded. Demographic information including age, sex, and body mass index (BMI) and medical comorbidities including American Society of Anesthesiologists (ASA) scores were evaluated. Patients were stratified by insurance type and length of stay (LOS), and 90-day ED visits and 90-day readmissions were assessed in univariable and multivariable analysis. RESULTS: A total of 3674 primary THA patients were included in the analysis (including 116 with Medicaid, 1713 with Medicare, and 1845 with other insurance providers). Medicaid patients had significantly higher ASA scores (P < .001) and BMI (P < .001), with corresponding increase in procedure duration (115 vs 99 vs 105 minutes; P < .001). They had a prolonged LOS (2.5 vs 2.5 vs 1.5 days; P < .001) compared with other insurances, but similar to Medicare patients. Following discharge, in multivariable analysis controlling for age, BMI, and ASA score, Medicare patients were significantly more likely to return to the ED (odds ratio, 3.15; 95% confidence interval, 1.88-5.27; P < .001) and be readmitted (odds ratio, 2.46; 95% confidence interval, 1.26-4.81; P = .009). CONCLUSION: Medicaid patients represent a higher risk cohort with increased resource utilization perioperatively, including longer LOS, and more 90-day ED visits and readmissions. This should be considered in outcome assessments and alternative expectations for the episode of care should be set for this population.

A Weighted Index of Elixhauser Comorbidities for Predicting 90-day Readmission After Total Joint Arthroplasty.

BACKGROUND: Evolving reimbursement models increasingly compel hospitals to assume costs for 90-day readmission after total joint arthroplasty. Although risk assessment tools exist, none currently reach the predictive performance required to accurately identify high-risk patients and modulate perioperative care accordingly. Although unlikely to perform adequately alone, the Elixhauser index is a set of 31 variables that may lend value in a broader model predicting 90-day readmission. METHODS: Elixhauser comorbidities were examined in 10,022 primary unilateral total joint replacements, of which 4535 were hip replacements and 5487 were knee replacements, all performed between June 2013 and January 2018 at a single tertiary referral center. Data were extracted from electronic medical records using structured query language. After randomizing to derivation (80%) and validation (20%) subgroups, predictive models for 90-day readmission were generated and transformed into a system of weights based on each parameter's relative performance. RESULTS: We observed 497 90-day readmissions (5.0%) during the study period, which demonstrated independent associations with 14 of the 31 Elixhauser comorbidity groups. A score created from the sum of each patient's weighted comorbidities did not lose substantial predictive discrimination (area under the curve: 0.653) compared to a comprehensive multivariable model containing all 31 unweighted Elixhauser parameters (area under the curve: 0.665). Readmission risk ranged from 3% for patients with a score of 0 to 27% for those with a score of 8 or higher. CONCLUSIONS: The Elixhauser comorbidity score already meets or exceeds the predictive discrimination of available risk calculators. Although insufficient by itself, this score represents a valuable summary of patient comorbidities and merits inclusion in any broader model predicting 90-day readmission risk after total joint arthroplasty. LEVEL OF EVIDENCE: III.