Radiographic comparison of eccentric stemmed vs. concentric stemless prosthetic humeral head positioning after anatomic total shoulder arthroplasty.

INTRODUCTION: Maintaining premorbid proximal humeral positioning is an essential consideration of anatomic total shoulder arthroplasty (aTSA), as malposition of the prosthetic humeral head can result in poor clinical outcomes. Stemless aTSA prosthetic heads are usually concentric, while stemmed aTSA prosthetic heads are typically eccentric in nature. Therefore, the purpose of this study was to compare the ability to restore native humeral head position between stemmed (eccentric) vs. stemless (concentric) aTSA. MATERIALS AND METHODS: Postoperative anteroposterior radiographs of 52 stemmed and 46 stemless aTSAs were analyzed. A best-fit circle was created using previously published and validated techniques to represent the premorbid humeral head position and axis of rotation. This circle was juxtaposed with another circle following the arc of the implant head. Next, the offset in center of rotation (COR), radius of curvature (RoC), and humeral head height above the greater tuberosity (HHH) were measured. Additionally, based on prior studies, an offset of >3 mm at any point between the implant head surface and premorbid best-fit circle was considered significant and further classified as overstuffed or understuffed. RESULTS: RoC deviation was significantly greater in the stemmed cohort than the stemless cohort (1.19 ± 1.37 mm vs. 0.65 ± 1.17 mm, P = .025). There was no statistically significant difference in deviation from premorbid humeral head between the stemmed and stemless cohorts for COR (3.20 ± 2.28 mm vs. 3.23 ± 2.09 mm, P = .800) or HHH (1.12 ± 3.27 mm vs. 0.92 ± 2.70 mm, P = .677). When comparing overstuffed implants to appropriately placed implants, there was a significant difference in overall COR deviation in stemmed implants (3.93 ± 2.51 mm vs. 1.92 ± 1.05 mm, P < .001). Superoinferior COR deviation (stemmed: 2.38 ± 3.01 mm vs. -0.61 ± 1.59 mm, P < .001; stemless: 2.70 ± 1.75 mm vs. -0.16 ± 1.87 mm, P < .001), mediolateral COR deviation (stemmed: 0.79 ± 2.65 mm vs. -0.62 ± 1.27 mm, P = .020; stemless: 0.40 ± 1.41 mm vs. -1.13 ± 1.96 mm, P = .020), and HHH (stemmed: 3.61 ± 2.73 mm vs. 0.50 ± 1.31 mm, P < .001; stemless: 3.98 ± 1.18 mm vs. 0.53 ± 1.41 mm, P < .001) were significantly different between overstuffed implants and appropriate implants in both the stemmed and stemless cohorts. DISCUSSION: Stemless and stemmed aTSA implants have similar rates of reproducing satisfactory postoperative humeral head COR with both producing COR deviation most commonly in the superomedial direction. Deviation in HHH contributes to overstuffing in both stemmed and stemless implants, COR deviation contributes to overstuffing in stemmed implants, while RoC (humeral head size) is not associated with overstuffing. Based on this study, it appears that neither eccentric nor concentric prosthetic heads are superior in recreating premorbid humeral head position.

Glenohumeral arthrodesis outcomes and complications: a systematic review.

BACKGROUND: The purpose of this study was to systematically review the evidence in the literature to determine the clinical outcomes following glenohumeral arthrodesis. METHODS: Two independent reviewers performed a literature search in the PubMed database based on Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies were included if they reported on outcomes following shoulder arthrodesis from the years of 2000-2022. Functional outcomes that were collected included the Subjective Shoulder Value, American Shoulder and Elbow Surgeons shoulder index score, visual analog scale pain score, and Oxford Shoulder Score. Range-of-motion data were also collected. RESULTS: This review included 17 studies, with a total of 316 patients, that met the inclusion criteria. The majority of the patients were male (67.4%), and the average age was 38.4 years (range, 7-82 years). The overall fusion rate was 88.7%, and the time to fusion was on average, 3.9 months (range, 2-8 months). Shoulder arthrodesis resulted in improvement in each of the functional outcomes assessed: Subjective Shoulder Value (preoperatively, 18.8; postoperatively, 43.9; and percent change, 132.8%), American Shoulder and Elbow Surgeons shoulder index score (postoperatively, 62.1), visual analog scale pain score (preoperatively, 8.5; postoperatively, 3.03; and percent change, 62.4%), and Oxford Shoulder Score (preoperatively, 9.4; postoperatively, 30.9; and percent change, 328.7%). The abduction, forward flexion, external rotation, and internal rotation range-of-motion measurements postoperatively were 57°, 64°, 3°, and 48°, respectively. Complications were reported in 33.6% of patients, with fractures (20.9%) and infections (18.6%) being the most common sources of complication. CONCLUSION: Shoulder arthrodesis provides improvement in functional outcomes for end-stage glenohumeral injuries; however, it is also associated with high rates of complications.

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.

Subscapularis repair for reverse shoulder arthroplasty: a systematic review and meta-analysis.

BACKGROUND: The purpose of this study is to perform a systematic review of the literature evaluating the importance of subscapularis repair in patients who underwent reverse shoulder arthroplasty (RSA). METHODS: A systematic search of articles in PubMed, EMBASE, and the Cochrane Library databases was carried out according to the PRISMA guidelines. Cohort studies comparing RSA with subscapularis repair vs. RSA without subscapularis repair were included. All statistical analysis was performed using Review Manager. A P value of <.05 was considered to be statistically significant. RESULTS: Seventeen studies with 2620 patients were included. Subscapularis repair resulted in less instability compared to without subscapularis repair (0.8% vs. 4.2%, P = .04), and there were no significant differences in rate of instability with lateralization (0.6% vs. 1.6%, P = .40), revision rates (2.6% vs. 3.9%, P = .62), and complication rates (7.7% vs. 4.9%, P = .21). Subscapularis repair had improved American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) scores (83.6 vs. 80.2, P = .02) and Constant scores (72.6 vs. 68.9, P < .01) but there was not a significant difference in visual analog scale pain scores (1.2 vs. 1.6, P = .11). Subscapularis repair had a significant difference in forward flexion (140° vs. 137°, P = .04) and internal rotation score (5.5 vs. 4.6, P = .001); however, there was no significant difference in external rotation (35° vs. 35°, P = .80) and abduction (117° vs. 123°, P = .13). CONCLUSION: This study found that RSA with subscapularis repair demonstrated a reduction in the occurrence of implant instability with medialized implants. However, subscapularis repair did not yield improvements in revision rates, complications, or instability with lateralized implants. Additionally, other outcome measures such as ASES, Constant score, and range of motion exhibited statistically significant improvements with subscapularis repair but did not surpass clinically significant thresholds.

Early clinical and patient-reported outcomes for arthroscopic and mini-open superior capsular reconstruction are similar for irreparable rotator cuff tears.

OBJECTIVES: The purpose of this study was to report and compare postoperative range of motion (ROM), patient-reported outcomes, and failure rates following superior capsular reconstruction (SCR) and to compare outcomes between arthroscopic and mini-open techniques. METHODS: All SCR procedures utilising dermal allograft with a minimum of 6 months of follow-up at multiple institutions between November 2015 and October 2019 were retrospectively reviewed. Preoperative patient demographics, imaging measurements, surgical technique (arthroscopic versus mini-open), and outcomes including pain scores, conversion to reverse shoulder arthroplasty, subsequent surgery, and postoperative ROM were recorded. Outcomes for arthroscopic versus mini-open approaches were compared via t-test, Fisher's exact test, or chi square test, as appropriate, with differences of p â€‹< â€‹0.05 considered significant. RESULTS: 180 total patients were included, including 98 who underwent arthroscopic SCR and 82 who underwent mini-open SCR. Final follow-up was at a mean of 32 months (standard deviation = 11 months). SCR improved pain (visual analog scale â€‹= â€‹4.4 pre-operatively vs. 1.4 post-operatively, p â€‹< â€‹0.0001) and ROMin active forward flexion (136° pre-operatively vs. 150° post-operatively, p â€‹= â€‹0.0012). No difference in post-operative pain visual analog scores was found between mini-open and arthroscopic cohorts (1.3 vs. 1.6, p â€‹= â€‹0.3432) at a mean of 14 months post-operatively. At a mean of 32 months post-operatively, there were no differences in ASES, QuickDASH, SST, WORC, or SANE scores between open and arthroscopic cohorts. There was no difference in rates of failure between mini-open and arthroscopic cohorts (15.9% vs. 17.3%, p â€‹= â€‹0.789). CONCLUSIONS: This study confirmed that SCR improves pain and ROM in the short term. Mini-open SCR appears to provide similar improvements in pain and ROM compared with arthroscopic SCR, as well as patient-reported outcomes at 3 years. No difference in failure rates was detected between the 2 procedures. LEVEL OF EVIDENCE: Level 3 evidence.

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.

Outcomes after bilateral shoulder arthroplasty: a systematic review.

The purpose of this systematic review was to report outcomes after bilateral shoulder arthroplasty including bilateral total shoulder arthroplasty (TSA), bilateral reverse shoulder arthroplasty (RSA), and ipsilateral TSA with contralateral RSA (TSA/RSA). Two reviewers independently performed a PRISMA-guided systematic search using MEDLINE/PubMed, Embase, and Cochrane Database of Systematic Reviews up to May 11, 2021. The databases were queried using the following search terms: (["bilateral" OR "contralateral"] AND "shoulder" AND ["arthroplast∗" OR "replacement"]). A total of 486 titles/abstracts were screened for eligibility and 19 studies were included in the final analysis. Risk of bias was assessed using Methodological Index for Nonrandomized Studies and Modified Coleman Methodology scores. Analysis compared overall results for bilateral shoulder arthroplasty and sub-group analyses compared TSA (all shoulders from bilateral TSA patients and the TSA shoulder in TSA/RSA patients) to RSA (all shoulders from bilateral RSA patients and the RSA shoulder in TSA/RSA patients), first shoulder arthroplasty to second contralateral shoulder arthroplasty, and interval between arthroplasty (IBA) <20 months to IBA ≥20 months. Nineteen studies analyzed bilateral TSA (n = 3), bilateral RSA (n = 7), and TSA/RSA (n = 8). The mean Methodological Index for Nonrandomized Studies was 18 and mean Modified Coleman Methodology Score was 74, with 63.2% of studies demonstrating level III evidence. A total of 2729 patients (30.4% male; mean age 72.2 years, mean follow-up 47.3 months, mean IBA 20 months) were analyzed. Postoperative forward flexion (142.0° vs. 129.6°), external rotation (ER) (42.5° vs. 25.6°), and internal rotation (60% reaching T12-T8 vs 85.7% reaching L3-L1) were higher for TSA when compared to RSA. Patient reported outcome measures such as Constant-Murley (73.2 vs. 59.2), American Shoulder and Elbow Surgeons (87.9 vs. 77.7), and Single Assessment Numeric Evaluation (SANE) (86.9 vs. 67.8) were higher for TSA when compared to RSA. Patients with IBA ≥20 months demonstrated greater ER and patient satisfaction than patients with IBA <20 months. Postoperative complication rates were 15.1% for TSA and 10.6% for RSA, while reoperation and revision rates were 13.7% for TSA and 7.1% for RSA. Bilateral shoulder arthroplasty results in improvements in motion, strength, pain, function, and high satisfaction. Bilateral TSA is associated with greater improvement in motion and function than bilateral RSA but higher complication, reoperation, and revision rates. IBA ≥20 months is associated with greater ER and satisfaction than IBA <20 months.

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.

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).

Concordance of Preoperative 3D Templating in Stemless Anatomic Total Shoulder Arthroplasty.

INTRODUCTION: Recent advances in preoperative 3D templating software allow surgeons to plan implant size and position for stemless total shoulder arthroplasty (TSA). Whether these preoperative plans accurately reflect intraoperative decisions is yet unknown, and the purpose of this study was to evaluate concordance between planned and actual implant sizes in a series of patients undergoing stemless TSA. METHODS: A retrospective cohort of consecutive, anatomic, stemless TSA cases performed by two surgeons between September 2019 and February 2021 was examined. Preoperative templated plans were collected using 3D planning software, and the sizes of planned glenoid, humeral head, and nucleus "stem" implants and other procedural data were recorded, along with sociodemographic information. These predicted parameters were compared with the implant sizes, and the concordance of these templated plans was quantified by direct comparison and bootstrapped simulations. RESULTS: Fifty cases met inclusion criteria, among which perfect concordance across all three implants was observed in 11 cases (22%). The glenoid implant had the highest concordance (80%) relative to the humeral head and nucleus implants (38% and 60%, respectively), which was statistically significant ( P < 0.001). Planned humeral head implants were more often oversized relative to their actual implanted size. However, 84% of the planned humeral heads were within 1 diameter size; in addition, 98% of the planned glenoid implants were within one size and all were within 10 mm of the implanted glenoid backside radius. All nucleus implants were within one size. DISCUSSION: Final implant sizes demonstrated variable concordance relative to preoperative plans, with glenoid implants having the highest accuracy and humeral heads having the highest variability. Multiple factors contributed to the varying concordances for the different implants, suggesting possible areas of improvement in this technology. These results may have implications for logistics, intraoperative efficiency, and overall cost and underscore the potential value of this technology. LEVEL OF EVIDENCE: Level III.

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.

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.

Comparison of Simulated Low-Dose and Conventional-Dose CT for Preoperative Planning in Shoulder Arthroplasty.

BACKGROUND: Shoulder computed tomography (CT) is commonly utilized in preoperative planning for total shoulder arthroplasty. Conventional-dose shoulder CT may expose patients to more ionizing radiation than is necessary to provide high-quality images for this procedure. The purpose of this study was to evaluate the utility of simulated low-dose CT images for preoperative planning using manual measurements and common preoperative planning software. METHODS: Eighteen shoulder CT scans obtained for preoperative arthroplasty planning were used to generate CT images as if they had been acquired at reduced radiation dose (RD) levels of 75%, 50%, and 25% using a simulation technique that mimics decreased x-ray tube current. This technique was validated by quantitative comparison of simulated low-dose scans of a cadaver with actual low-dose scans. Glenoid version, glenoid inclination, and humeral head subluxation were measured using 2 commercially available software platforms and were also measured manually by 3 physicians. These measurements were then analyzed for agreement across RD levels for each patient. Tolerances of 5° of glenoid version, 5° of glenoid inclination, and 10% humeral head subluxation were used as equivalent for preoperative planning purposes. RESULTS: At all RD levels evaluated, the preoperative planning software successfully segmented the CT images. Semiautomated software measurement of 25% RD images was within tolerances in 99.1% of measurements; for 50% RD images, within tolerances in 96.3% of measurements; and for 75% RD images, within tolerances in 100% of measurements. Manual measurements of 25% RD images were within these tolerances in 95.1% of measurements; for 50% RD images, in 98.8% of measurements; and for 75% RD images, in 99.4% of measurements. CONCLUSIONS: Simulated low-dose CT images were sufficient for reliable measurement of glenoid version, glenoid inclination, and humeral head subluxation by preoperative planning software as well as by physician-observers. These findings suggest the potential for substantial reduction in RD in preoperative shoulder CT scans without compromising surgical planning. CLINICAL RELEVANCE: The adoption of low-dose techniques in preoperative shoulder CT may lower radiation exposure for patients undergoing shoulder arthroplasty, without compromising image quality.

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.

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.

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.

The Efficacy of Peroxide Solutions in Decreasing Cutibacterium acnes Burden Around the Shoulder.

BACKGROUND: Cutibacterium acnes is a common pathogen associated with surgical site infection after shoulder surgery; current standard of care products are largely ineffective at reducing C acnes bacterial burden before surgery. The purpose of this systematic meta-analysis was to assess the efficacy of peroxide-containing solutions (PCS) in decreasing the C acnes burden on the shoulder. METHODS: This was a systematic review of all level I and II studies investigating the effect of peroxidase-containing products for skin preparation. We extracted data regarding demographics, treatment details and timing, study methodology, and culture positivity. Forest plots were used to determine the pooled efficacy of peroxide solutions versus control. RESULTS: Seven studies with 412 patients were eligible for inclusion. Notable heterogeneity was observed in the manner and timing of peroxide application. Two studies applied PCS at the time of surgery; four studies applied PCS in the 24- to 72-hour period leading up to culture acquisition. Compared with the placebo, peroxide significantly diminished C acnes culture positivity (Hazard Ratio 0.174, P = 0.009). When considering using peroxide-containing products in the period leading up to surgery or at the time of surgery, in addition to standard preparation, the addition of peroxide significantly diminished C acnes culture positivity (HR 0.467, P = 0.004). Owing to study heterogeneity, we could not make notable comparisons based on the timing or duration of benzoyl peroxides application. CONCLUSIONS: Despite heterogeneity in study design, pooled results of high-quality data suggest that the addition of PCS can markedly reduce C acnes bioburden. This review was not able to identify the ideal regimen for the utilization of PCS for reduction of C acnes burden. LEVEL OF EVIDENCE: Level II.

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.

Intraoperative fractures in shoulder arthroplasty: risk factors and outcomes.

BACKGROUND: The incidence of shoulder arthroplasty in the United States continues to increase, and while the risk of intraoperative complications such as fracture remains relatively low, there has been little investigation into whether certain patient-specific risk factors predispose to this complication. This study characterizes the incidence of intraoperative fracture during shoulder arthroplasty and additionally hypothesizes that certain risk factors may exist in addition to potentially leading to worsened near-term outcomes. METHODS: An institutional database of shoulder arthroplasties (N = 1773; 994 anatomic, 779 reverse) was retrospectively reviewed, and the operative reports for each case were examined for documentation of an intraoperative fracture, including during which surgical step the fracture took place. Various preoperative and intraoperative factors were tested for comparative significance (P < .05) using chi-square and Kruskal-Wallis tests as appropriate. Length of stay, 90-day readmission, and discharge to rehabilitation or skilled nursing facility (SNF) were further examined as secondary outcomes. RESULTS: Twenty-one (1.2%) intraoperative fractures were documented, a majority of which occurred in reverse shoulder arthroplasties compared to anatomic procedures (overall incidence: 2.5% vs. 0.2%, P < .001). These most commonly occurred during either stem broaching (33%) or seating (33%) and were most likely to involve the metaphysis (53%) or greater tuberosity (33%). Five fractures occurred during revision arthroplasty, while 16 fractures occurred during primary procedures (overall incidence: 3.0 vs. 1.0%, P = .03). Patient factors reaching statistical significance included female gender and liver disease, while age and smoking history were notably not associated with intraoperative fracture. The fracture cohort had a significantly longer mean length of stay (2.42 vs. 2.17 days, P < .001). While the rates of 90-day readmission and discharge to SNF/rehab were higher in the fracture cohort, these values did not reach statistical significance. CONCLUSION: Intraoperative fractures are a rare complication (1.2%) in shoulder arthroplasty, with reverse shoulder arthroplasty, revision cases, and female gender associated with an elevated overall risk. While these patients had a longer inpatient hospitalization, the substantially higher rates of 90-day readmission and discharge to SNF/rehab did not reach significance in our limited institutional cohort. The aforementioned incidence and risk factors serve as crucial evidence for use during the preoperative counseling process with patients as part of a shared decision-making model.