Subacromial Balloon Spacer Implantation Is a Promising Alternative for Patients With Massive Irreparable Rotator Cuff Tears: A Systematic Review.

PURPOSE: To provide an overview of the existing literature on subacromial balloon spacers for the treatment of massive irreparable rotator cuff tears, in an effort to inform surgeons of the procedure's clinical effectiveness. METHODS: The PubMed, Scopus, and Ovid EMBASE databases were queried to identify studies evaluating the clinical, radiographic, and patient-reported outcomes of patients indicated for subacromial balloon spacer implantation. The following datapoints were extracted: study demographics, patient baseline characteristics, and postoperative outcomes of interest. Outcomes were evaluated at baseline and at the longest available follow-up period. RESULTS: A total 766 patients were included among 22 included studies, with an average follow-up of 27.54 months. Improvements were seen for all clinical and patient-reported outcomes: forward elevation (ranging from 9.20 to 90.00° improvement), external rotation (ranging from 2.00 to 22.00°), abduction (ranging from 14.00 to 95.00°), Total Constant Score (ranging from 7.70 to 50.00), American Shoulder and Elbow Surgeons score (ranging from 24.60 to 59.84), Oxford Shoulder Score (ranging from 7.20 to 22.20), and pain score (ranging from 3.57 to 6.50). Minimal differences were seen in acromiohumeral interval (ranging from -2.00 to 1.27). Reoperation and complication rates ranged from 0% to 33% and 0% to 19.64%, respectively. CONCLUSIONS: The short-term results of subacromial balloon spacers for management of massive rotator cuff tears demonstrate clinically relevant improvements in shoulder range of motion and substantial improvements in patient-reported outcome measures. Of note, minimal change in acromiohumeral interval was seen on postoperative radiography, and wide variations in complication and reoperation rates were reported across studies. LEVEL OF EVIDENCE: Level IV, systematic review of Level I-IV studies.

The fragility of statistical findings in the reverse total shoulder arthroplasty literature: a systematic review of randomized controlled trials.

BACKGROUND: Reverse total shoulder arthroplasty (RTSA) has seen increasing utilization as an effective intervention for a wide variety of shoulder pathologies. The scope and indications for growth are often driven by findings from randomized controlled trials (RCTs) guiding surgical decision-making for RTSA. In this study, we utilized the fragility index (FI), reverse fragility index (rFI), and fragility quotient (FQ) to assess the robustness of outcomes reported in RCTs in the RTSA literature. METHODS: PubMed, Embase, and MEDLINE were queried for RCTs (Jan. 1, 2010-Mar. 31, 2023) in the RTSA literature reporting dichotomous outcomes. The FI and rFI were defined as the number of outcome reversals required to alter statistical significance for significant and nonsignificant outcomes, respectively. The FQ was determined by dividing the FI by the sample size of each study. Subgroup analysis was performed based on outcome category. RESULTS: One hundred seventy-six RCTs were screened with 18 studies included. The median FI across 59 total outcomes was 4 (interquartile range [IQR]: 3-5) with an associated FQ of 0.051 (IQR: 0.029-0.065). Thirteen outcomes were statistically significant with a median FI of 3 (IQR: 1-4) and FQ of 0.033 (IQR: 0.012-0.066). Forty-six outcomes were nonsignificant with a median rFI of 4 (IQR: 3-5) and FQ of 0.055 (IQR: 0.032-0.065). The most fragile outcome category was revision/reoperations with a median FI of 2.50 (IQR: 1.00-3.25), followed by clinical score/outcome (median FI: 3.00), complications (median FI: 4.00), "other" (median FI: 4.00), and radiographic findings (median FI: 5.00). Notably, the number of patients lost to follow-up was greater than or equal to the FI for 59% of outcomes. CONCLUSION: The statistical findings in RTSA RCTs are fragile and should be interpreted with caution. Reversal of only a few outcomes, or maintaining postoperative follow-up, may be sufficient to alter significance of study findings. We recommend standardized reporting of P values with FI and FQ metrics to allow clinicians to effectively assess the robustness of study findings.

Surgical treatment of displaced proximal humerus fractures is associated with decreased 1-year mortality in patients aged 65 years and older: a retrospective study of Medicare patients.

BACKGROUND: Proximal humerus fracture (PHF) is a risk factor for 1-year mortality. This study aimed to determine if surgery is associated with lower mortality compared to nonoperative treatment following PHF in older patients. METHODS: This retrospective cohort study used the Medicare Limited Data set. Patients aged 65 years and older with a PHF diagnosis in 2017-2020 were included. Treatment was classified as nonoperative, open reduction internal fixation (ORIF), total shoulder arthroplasty (TSA), or hemiarthroplasty. Multivariable logistic regression models examined (a) predictors of treatment type and (b) the association of treatment type with 1-year mortality, adjusting for patient demographics, comorbidities, frailty, and fracture severity among other variables. A subgroup analysis examined how the relationship between treatment type and 1-year mortality varied based on fracture severity. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) are reported. RESULTS: In total, 49,072 patients were included (mean age = 76.6 years, 82.3% female). Most were treated nonoperatively (77.5%), 10.9% underwent ORIF, 10.6% underwent TSA, and 1.0% underwent hemiarthroplasty. Examples of factors associated with receipt of operative (versus nonoperative treatment) included worse fracture severity and lower frailty. The 1-year mortality rate after the initial PHF diagnosis was 11.0% for the nonoperative group, 4.0% for ORIF, 5.2% for TSA, and 6.0% for hemiarthroplasty. Compared to nonoperative treatment, ORIF (aOR 0.55; 95% CI [0.47, 0.64]; P < .001) and TSA (aOR 0.59; 95% CI [0.50, 0.68]; P < .001) were associated with decreased odds of 1-year mortality. In the subgroup analysis, ORIF and TSA were associated with a lower 1-year mortality risk for 2-part and 3-/4-part fractures. CONCLUSIONS: Compared to nonoperative treatment, surgery (particularly TSA and ORIF) was associated with a decreased odds of 1-year mortality. This relationship remained significant for 2-part and 3-/4-part fractures after stratifying by fracture severity.

Did the Comprehensive Care for Joint Replacement Bundled Payment Program Impact Sex Disparities in Total Hip and Knee Arthroplasties?

BACKGROUND: Sex disparities have been noted across various aspects of total hip/knee arthroplasty (THA/TKA). Given incentives to standardize care, bundled payment initiatives including the Comprehensive Care for Joint Replacement (CJR) program may reduce disparities. This study aimed to assess the CJR program's impact on sex disparities in THA/TKA care and outcomes. METHODS: This retrospective cohort study included 259,673 THAs (61.7% women) and 506,311 TKAs (64.0% women) from a large national database (2013 to 2017). Sex disparities were assessed for care and outcomes related to the period (1) before surgery, (2) during hospitalization for THA/TKA, and (3) after discharge. Disparities were reported as women:men ratios. Difference-in-differences analyses estimated the impact of the CJR program on pre-existing sex disparities. RESULTS: For both THA and TKA, women were less likely than men to present with a Charlson-Deyo comorbidity index >0 (women:men ratio 0.88 to 0.92), but were more likely to require blood transfusions (women:men ratio 1.48 to 1.79) and be discharged to institutional postacute care (women:men ratio 1.50 to 1.66). Difference-in-differences models demonstrated that the CJR bundled payment program reduced sex disparities in institutional postacute care discharges (THA: -2.28%; 95% confidence interval [CI] -4.20 to -0.35%, P = .02; TKA: -2.07%; 95% CI -3.93 to -0.20%; P = .03) and THA 90-day readmissions (-1.00%, 95% CI -1.88 to -0.13%, P = .02), indicating a differential impact of CJR in women versus men for some outcomes. CONCLUSIONS: While sex disparities in THA/TKA persist, the CJR program demonstrates potential to impact such differences. Future research should focus on how potential mechanisms could be leveraged to reduce disparities.

Mid-term outcomes following reverse total shoulder arthroplasty.

PURPOSE: The utilization of reverse total shoulder arthroplasty now exceeds the incidence of anatomic shoulder arthroplasty. Previous mid-to-long-term studies on rTSA have reported a decrease in shoulder function as follow-up increased. The purpose of this study was to provide data on mid-term outcomes and implant survival in a series focusing on reverse total shoulder arthroplasty. MATERIALS AND METHODS: Demographic information such as age at surgery, revision surgery status, BMI, and smoking status were recorded. The clinical endpoints measured in this study were range of motion scores (forward elevation, external rotation, internal rotation) and patient reported outcomes (VAS, ASES, SST). Radiographic variables captured included preoperative glenoid morphology, humeral lucency, and glenoid loosening. RESULTS: Fifty-six shoulders were included in this study. The overall mean age at surgery was 72.5 ± 7.2 years with an average follow-up time of 6.8 ± 3.5 years. The mean BMI was 28.1 ± 5.5. All measurements of range of motion saw significant and sustained improvements. Overall, forward elevation improved from 82° preoperatively to 133° postoperatively (p < 0.01). External rotation improved from 23° preoperatively to 36° (p < 0.01), while internal rotation improved from L3 to L1 (p = 0.05). ASES scores improved from 31 preoperatively to 70 postoperatively (p < 0.01). SST scores improved from 2 preoperatively to 7 (p < 0.01). VAS pain index scores improved from 6 to 2 following surgery (p < 0.01). Postoperative scapular notching was seen in 18 patients at final follow-up. Glenoid loosening was seen in 3 shoulders. Humeral loosening was seen in 18 shoulders. Tuberosity resorption was seen in 8 shoulders. The 5 year survival estimate was 98%, and the 10 year survival estimate was 83%. CONCLUSION: In this series, we found that rTSA provides mid-term improvements in range of motion in patients while reducing pain levels. When considered together, this demonstrates that most patients undergoing rTSA can have excellent use of their shoulder from age at surgery to end-of-life.

Superior migration of the humeral head does not significantly affect outcomes at an average of 11 years after total shoulder arthroplasty.

BACKGROUND: Superior migration of the humeral head has been linked with rotator cuff dysfunction and glenoid loosening after total shoulder arthroplasty (TSA). We aimed to determine if superior migration was associated with poor shoulder function following anatomic TSA at long-term follow-up. METHODS: In this retrospective cohort study, we reviewed patients undergoing TSA by a single surgeon at an urban, academic institution. To study the effect of superior migration on TSA outcomes, we stratified the cohort by ≥ and <7 mm of acromiohumeral interval (AHI) and compared range of motion and patient reported outcomes (PROs). Clinical variables included preoperative and postoperative forward elevation (FE), internal rotation, external rotation, visual analog scale, American Shoulder and Elbow Surgeons shoulder score, and Simple Shoulder Text score. Radiographic variables included immediate postoperative and long-term follow-up AHI, lateral humeral offset, and glenoid loosening scores. RESULTS: After applying exclusion criteria, 121 TSAs were included. The mean age was 63.9 ± 9.5 years, and 66 surgeries (55%) were in male patients. The mean follow-up for our cohort was 11.2 years (range, 5-26 years). Nine shoulders underwent revision surgery. All range of motion and PROs improved significantly from preoperative to the most recent postoperative follow-up. The mean AHI immediately following surgery was 10.9 ± 4.1 mm, while the mean AHI at most recent follow-up was 8.4 ± 3.5 mm. Glenoid loosening was observed in 29 (23.8%) shoulders at the most recent follow-up appointment. Although AHI correlated weakly with FE (r = 0.252; P = .006), we did not observe a clear threshold of migration which led to degraded function. Importantly, glenoid loosening was not related to AHI at long-term follow-up (P = .631). None of FE, internal rotation, external rotation, visual analog scale, American Shoulder and Elbow Surgeons shoulder score, Simple Shoulder Text, or revisions were significantly different between patients with ≥ and <7 mm of AHI. CONCLUSION: Our results suggest that anatomic TSA provides durable improvements to pain, function, and PROs despite changes to the AHI.

Tendon progenitor cells as biological augmentation improve functional gait and reduce scar formation after rotator cuff repair.

BACKGROUND: High rates of structural failure are reported after rotator cuff repairs due to inability to recreate the native enthesis during healing. The development of biological augmentation methods that mitigate scar formation and regenerate the enthesis is still an unmet need. Since neonatal enthesis is capable of regeneration after injury, this study tested whether delivery of neonatal tendon progenitor cells (TPCs) into the adult injured environment can enhance functional and structural supraspinatus enthesis and tendon healing. METHODS: TPCs were isolated from Ai14 Rosa26-TdTomato mouse Achilles tendons and labeled using adenovirus-Cre. Fifty-two CB57BL/6J mice underwent detachment and acute repair of the supraspinatus tendon and received either a fibrin-only or TPC-fibrin gel. Immunofluorescence analysis was carried out to determine cellularity (DAPI), fibrocartilage (SOX9), macrophages (F4/80), myofibroblasts (α-smooth muscle actin), and scar (laminin). Assays for function (gait and biomechanical testing) and structure (micro-computed tomography imaging, picrosirius red/Alcian Blue staining, type I and III collagen staining) were carried out. RESULTS: Analysis of TdTomato cells after injury showed minimal retention of TPCs by day 7 and day 14, with detected cells localized near the bursa and deltoid rather than the enthesis/tendon. However, TPC delivery led to significantly increased %Sox9+ cells in the enthesis at day 7 after injury and decreased laminin intensity across almost all time points compared to fibrin-only treatment. Similarly, TPC-treated mice showed gait recovery by day 14 (paw area and stride length) and day 28 (stance time), while fibrin-treated mice failed to recover gait parameters. Despite improved gait, biomechanical testing showed no differences between groups. Structural analysis by micro-computed tomography suggests that TPC application improves cortical thickness after surgery compared to fibrin. Superior collagen alignment at the neo-enthesis was also observed in the TPC-augmented group at day 28, but no difference was detected in type I and III collagen intensity. CONCLUSION: We found that neonatal TPCs improved and restored functional gait by reducing overall scar formation, improving enthesis collagen alignment, and altering bony composition response after supraspinatus tendon repair. TPCs did not appear to integrate into the healing tissue, suggesting improved healing may be due to paracrine effects at early stages. Future work will determine the factors secreted by TPCs to develop translational targets.

Long-term clinical and radiographic outcomes of total shoulder arthroplasty in patients under age 60 years.

BACKGROUND: We aimed to characterize the long-term clinical and radiographic outcomes of total shoulder arthroplasty (TSA) in patients aged < 60 years. We hypothesized meaningful improvements in shoulder functionality and pain with TSA and an acceptably low rate of prosthesis complications and revisions. METHODS: This was a retrospective cohort study of 29 patients (34 shoulders) undergoing TSA before age 60 years with a minimum follow-up period of 10 years. Shoulder range of motion, functionality (American Shoulder and Elbow Surgeons and Simple Shoulder Test scores), and pain (visual analog scale score) were evaluated. Radiographs were assessed for lateral humeral offset, the acromiohumeral interval, and glenoid loosening. RESULTS: The mean age of the patients was 54.4 ± 5.5 years (range, 35.5-59.8 years), with a mean follow-up period of 16.1 ± 4.5 years (range, 10.0-26.1 years). In patients aged < 60 years, TSA significantly improved forward elevation (from 119° ± 26° to 146° ± 21°, P = .0002), external rotation (from 21° ± 25° to 52° ± 15°, P = .0001), and internal rotation (from L5 to L1, P = .002). Additionally, TSA significantly increased American Shoulder and Elbow Surgeons scores (from 32 ± 20 to 64 ± 27, P = .0008) and Simple Shoulder Test scores (from 3 ± 2 to 7 ± 4, P = .0004) and reduced visual analog scale pain scores (from 7 ± 3 to 3 ± 3, P = .0001). Radiographically, there was no significant difference in mean lateral humeral offset (13 ± 6 mm vs. 10 ± 12 mm, P = .472) or the mean acromiohumeral interval (20 ± 4.2 mm vs. 16 ± 6 mm, P = .061) between immediate postoperative and final follow-up radiographs. Radiographic evidence of glenoid loosening was noted in 2 patients. Complications occurred in 6 patients (17.6%), all of which were cases of aseptic glenoid loosening. Ultimately, 4 patients underwent conversion to a reverse TSA and 2 underwent arthroscopic glenoid removal. The rate of prosthesis survivorship was 97.1% (95% confidence interval [CI], 91.4%-100%) at 10 years, 85.4% (95% CI, 73.7%-97.2%) at 15 years, and 80.1% (95% CI, 65.1%-98.4%) at 20 years. DISCUSSION: TSA consistently improved shoulder functionality and reduced pain while limiting the need for further revisions. These findings suggest that TSA is a viable treatment option for glenohumeral arthritis in younger patients.

Safety of Tranexamic Acid in Hip and Knee Arthroplasty in High-risk Patients.

BACKGROUND: With increasing use of tranexamic acid in total hip and knee arthroplasties, safety concerns remain. Using national claims data, this study examined tranexamic acid use in patients with preexisting comorbidities. The hypothesis was that tranexamic acid use is not associated with increased complication risk in hip and knee arthroplasty patients with comorbidities. METHODS: Among 765,011 total hip/knee arthroplasties (2013 to 2016, Premier Healthcare claims), tranexamic acid use was assessed in three high-risk groups: group I with patients with a history of venous thromboembolism, myocardial infarction, seizures, or ischemic stroke/transient ischemic attack (n = 27,890); group II with renal disease (n = 44,608); and group III with atrial fibrillation (n = 45,952). The coprimary outcomes were blood transfusion and new-onset "composite complications" (venous thromboembolism, myocardial infarction, seizures, and ischemic stroke/transient ischemic attack). Associations between tranexamic acid use and outcomes were measured separately by high-risk group. The odds ratios and Bonferroni-adjusted 99.9% CIs are reported. RESULTS: Overall, 404,974 patients (52.9%) received tranexamic acid, with similar frequencies across high-risk groups I (13,004 of 27,890 [46.6%]), II (22,424 of 44,608 [50.3%]), and III (22,379 of 45,952 [48.7%]). Tranexamic acid use was associated with decreased odds of blood transfusion in high-risk groups I (721 of 13,004 [5.5%] vs. 2,293 of 14,886 [15.4%]; odds ratio, 0.307; 99.9% CI, 0.258 to 0.366), group II (2,045 of 22,424 [9.1%] vs. 5,159 of 22,184 [23.3%]; odds ratio, 0.315; 99.9% CI, 0.263 to 0.378), and group III (1,325 of 22,379 [5.9%] vs. 3,773 of 23,573 [16.0%]; odds ratio, 0.321; 99.9% CI, 0.266 to 0.389); all adjusted comparisons P < 0.001. No increased odds of composite complications were observed in high-risk group I (129 of 13,004 [1.0%] vs. 239 of 14,886 [1.6%]; odds ratio, 0.89, 99.9% CI, 0.49 to 1.59), group II (238 of 22,424 [1.1%] vs. 369 of 22,184 [1.7%]; odds ratio, 0.98; 99.9% CI, 0.58 to 1.67), and group III (187 of 22,379 [0.8%] vs. 290 of 23,573 [1.2%]; odds ratio, 0.93; 99.9% CI, 0.54 to 1.61); all adjusted comparisons P > 0.999. CONCLUSIONS: Although effective in reducing blood transfusions, tranexamic acid is not associated with increased complications, irrespective of patient high-risk status at baseline.

Administration of tranexamic acid during total shoulder arthroplasty is not associated with increased risk of complications in patients with a history of thrombotic events.

INTRODUCTION: Tranexamic acid (TXA) has been shown to reduce blood loss and transfusion risk in various orthopedic surgeries including shoulder arthroplasty. However, concerns still exist regarding its use in patients with a history of thrombotic events. Using national claims data, we aimed to study the safety of TXA administration in shoulder arthroplasty patients with a history of thrombotic events. METHODS: We used retrospective national claims data (Premier Healthcare) on 71,174 patients who underwent a total or reverse shoulder arthroplasty between 2010 and 2016. TXA use was evaluated specifically within a subgroup of patients with a history of thrombotic events such as myocardial infarction, deep venous thrombosis, pulmonary embolism, transient ischemic attack, or ischemic stroke. Studied outcomes were blood transfusion need, complications (including acute renal failure, new onset myocardial infarction, deep venous thrombosis, pulmonary embolism, transient ischemic attack, or ischemic stroke), and cost and length of hospitalization. Mixed-effects models measured the association between TXA use and outcomes, separately in patients with and without a history of thrombotic events. Odds ratios (OR) or percent change for continuous outcomes with 95% confidence intervals (CI) were reported. RESULTS: Overall, TXA was used in 13.7% (n = 9735) of patients, whereas 10.5% (n = 7475) of patients had a history of a thrombotic event. After adjustment for relevant covariates, TXA use (compared with no TXA use) in patients without a history of thrombotic events was associated with decreased odds of blood transfusions (OR, 0.48; CI, 0.24-0.98; P = .0444), whereas no increased odds for complications were observed (OR, 0.83; CI, 0.40-1.76; P = .6354). Similar results were observed in patients with a history of thrombotic events. Moreover, in this subgroup, TXA use was associated with a slight reduction in hospitalization cost (-8.9% CI: -13.1%; -4.6%; P < .0001; group median $18,830). CONCLUSIONS: Among shoulder arthroplasty patients, TXA use was not associated with increased complication odds, independent of a history of thrombotic events. These findings are in support of wider TXA use.

Consensus statement on the treatment of massive irreparable rotator cuff tears: a Delphi approach by the Neer Circle of the American Shoulder and Elbow Surgeons.

BACKGROUND: Management of massive irreparable rotator cuff tears (MIRCTs) remains controversial owing to variability in patient features and outcomes contributing to a lack of unanimity in treatment recommendations. The purpose of this study was to implement the Delphi process using experts from the Neer Circle of the American Shoulder and Elbow Surgeons to determine areas of consensus regarding treatment options for a variety of MIRCTs. METHODS: A panel of 120 shoulder surgeons were sent a survey regarding MIRCT treatments including arthroscopic débridement and partial cuff repair, graft augmentation, reverse shoulder arthroplasty (RSA), superior capsular reconstruction (SCR), and tendon transfer. An iterative Delphi process was then conducted with a first-round questionnaire consisting of 13 patient factors with the option for open-ended responses to identify important features influencing the treatment of MIRCTs. The second-round survey sought to determine the importance of patient factors related to the 6 included treatment options. A third-round survey asked participants to classify treatment options for 60 MIRCT patient scenarios as either preferred treatment, acceptable treatment, not acceptable/contraindicated, or unsure/no opinion. Patient scenarios were declared to achieve consensus for the preferred and not acceptable/contraindicated categories when at least 80% of the survey respondents agreed on a response, and a 90% threshold was required for the acceptable treatment category, defined by an acceptable treatment or preferred treatment response. RESULTS: Seventy-two members agreed to participate and were deemed to have the requisite expertise to contribute based on their survey responses regarding clinical practice and patient volume. There were 20 clinical scenarios that reached 90% consensus as an acceptable treatment, with RSA selected for 18 scenarios and arthroscopic débridement and/or partial repair selected for 2. RSA was selected as the singular preferred treatment option in 8 scenarios. Not acceptable/contraindicated treatment options reached consensus in 8 scenarios, of which, 4 related to SCR, 3 related to RSA, and 1 related to partial repair with graft augmentation. CONCLUSION: This Delphi process exhibited significant consensus regarding RSA as a preferred treatment strategy in older patients with pseudoparesis, an irreparable subscapularis, and dynamic instability. In addition, the process identified certain unacceptable treatments for MIRCTs such as SCR in older patients with pseudoparesis and an irreparable subscapularis or RSA in young patients with an intact or reparable subscapularis without pseudoparesis or dynamic instability. The publication of these scenarios and areas of consensus may serve as a useful guide for practitioners in the management of MIRCTs.

Metric Selection, Metric Targets, and Risk Adjustment Should be Considered in the Design of Gainsharing Models for Bundled Payment Programs in Total Joint Arthroplasty.

BACKGROUND: Under bundled payment models, gainsharing presents an important mechanism to ensure engagement and reward innovation. We hypothesized that metric selection, metric targets, and risk adjustment would impact surgeons' performance in gainsharing models. METHODS: Patients undergoing total joint arthroplasty at an urban health system from 2017 to September 2018 were included. Gainsharing metrics included the following: length of stay, % discharge-to-home, 90-day readmission rate, % of patients with episode spend under target price, and % of patients with patient-reported outcomes (PROs) collected. Four scenarios were created to evaluate how metric selection/adjustment impacted surgeons' performance designation: scenario 1 used "aspirational targets" (>60th percentile), scenario 2 used "acceptable targets" (>50th percentile), scenario 3 risk-adjusted surgeon performance prior to comparing aspirational targets, and scenario 4 included a PRO collection metric. Number of metrics achieved determined performance tier, with higher tiers getting a greater share of the gainsharing pool. RESULTS: In total, 2776 patients treated by 12 surgeons met inclusion criteria (mean length of stay 3.0 days, readmission rate 4.0%, discharge-to-home 74%, episode spend under target price 85%, PRO collection 56%). Lowering of metric targets (scenario 1 vs. 2) resulted in a 75% increase in the number of high performers and 98% of the gainsharing pool being eligible for distribution. Risk adjustment (scenario 3) caused 50% of providers to move to higher performance tiers and potential payments to increase by 28%. Adding the PRO metric did not change performance. CONCLUSION: Quality metric/target selection and risk adjustment profoundly impact surgeons' performance in gainsharing contracts. This impacts how successful these contracts can be in driving innovation and dis-incentivizing the "cherry picking" of patients. LEVEL OF EVIDENCE: Level III.

Peripheral nerve block use in ankle arthroplasty and ankle arthrodesis: utilization patterns and impact on outcomes.

PURPOSE: Ankle arthrodesis and total ankle arthroplasty (TAA) are often associated with significant postoperative pain. While this may be mitigated by the use of peripheral nerve blocks (PNB), large-scale data are lacking. Using national data, we aimed to evaluate PNB utilization pattern and its impact on outcomes. METHODS: This retrospective cohort study utilized data from the nationwide database (2006-2016) on TAA (n = 5,290) and ankle arthrodesis (n = 14,709) procedures. PNB use was defined from billing; outcomes included opioid utilization, length and cost of stay, discharge to a skilled nurse facility, and opioid-related complications. Mixed-effects models estimated the association between PNB use and outcomes, separate by procedure type and inpatient/outpatient setting. We report odds ratios and 95% confidence intervals (CI). RESULTS: Overall, PNB was utilized in 8.7% of TAA and 9.9% of ankle arthrodesis procedures, with increased utilization from 2006 to 2016 of 2.6% to 11.3% and 5.2% to 12.0%, respectively. After adjustment for relevant covariates, PNB use was significantly associated with decreased total opioid utilization specifically in the inpatient setting in TAA ( - 16.9% CI  - 23.9%;  - 9.1%) and ankle arthrodesis procedures ( - 18.9% CI  - 24.4;  - 13.0%), this was particularly driven by a decrease in opioid utilization on the day of surgery. No clinically relevant effects were observed for other outcomes. CONCLUSION: PNB utilization is associated with substantial reductions in opioid utilization, particularly in the inpatient setting. Our study is in support of a wider use of this analgesic technique, which may translate into more benefits in terms of clinical outcomes and resource utilization. LEVEL OF EVIDENCE: III.

Enthesis regeneration: a role for Gli1+ progenitor cells.

The tendon enthesis originates from a specific pool of hedgehog-active Gli1+ progenitor cells that differentiate and produce mineralized fibrocartilage. The current study investigated the regenerative capacity of this cell population by comparing the responses of early postnatal and mature entheses to injury. Lineage tracing studies demonstrated that the original Gli1+ cell population had the capacity to heal immature entheses after injury, but this capacity was lost after the cells differentiated into mature fibrochondrocytes. To further examine the involvement of Gli1+ cells and hedgehog signaling in enthesis healing, Gli1 expression was examined via lineage tracing approaches and the effect of Smo deletion was examined in the injured entheses. Immature injured entheses retained high levels of Gli1 expression, a marker of hedgehog activation, consistent with non-injured controls. In contrast, injured mature entheses had few Gli1+ cells early in the healing process, with limited recovery of the cell population later in the healing process. These results suggest that the presence of activated hedgehog signaling in enthesis cells early in the healing process may enhance healing of enthesis injuries by mimicking developmental processes.

Characteristics of Antibiotic Prophylaxis and Risk of Surgical Site Infections in Primary Total Hip and Knee Arthroplasty.

BACKGROUND: Despite numerous antibiotic prophylaxis options for total hip arthroplasty (THA) and total knee arthroplasty (TKA), an assessment of practice patterns and comparative effectiveness is lacking. We aimed to characterize antibiotic utilization patterns and associations with infection risk and hypothesized differences in infection risk based on regimen. METHODS: A retrospective cohort study was performed using data from 436,724 THA and 862,918 TKA (Premier Healthcare Database; 2006-2016). Main exposures were antibiotic type and duration: day of surgery only (day 0) or through postoperative day 1 (day 1). The primary outcome was surgical site infection (SSI) <30 days postoperation. Mixed-effect models measured associations between prophylaxis regimen and SSI as odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: SSI prevalence was 0.21% (n = 914) for THA and 0.22% (n = 1914) for TKA. Among THA procedures, the most commonly used antibiotics were cefazolin (74.1%), vancomycin (8.4%), "other" antibiotic combinations (7.1%), vancomycin + cefazolin (5.1%), and clindamycin (3.3%). Here, 51.8% received prophylaxis on day 0 only, whereas 48.2% received prophylaxis through day 1. Similar patterns existed for TKA. Relative to cefazolin, higher SSI odds were seen with vancomycin (OR = 1.36; CI 1.09-1.71) in THA and with vancomycin (OR = 1.29; CI = 1.10-1.52), vancomycin + cefazolin (OR = 1.35; CI = 1.12-1.64), clindamycin (OR = 1.38; CI = 1.11-1.71), and "other" antibiotic combinations (OR = 1.28; CI = 1.07-1.53) in TKA. Prophylaxis duration did not alter SSI odds. Results were corroborated in sensitivity analyses. CONCLUSION: Antibiotic prophylaxis regimens other than cefazolin were associated with increased SSI risk among THA/TKA patients. These findings emphasize a modifiable intervention to mitigate infection risk.

Hospital-Specific Total Joint Arthroplasty Casemix and Patient Flows in the Era of Payment Reform: Impact on Resource Utilization Among New York State Hospitals.

BACKGROUND: Bundled payment models may lead to selection of healthier total joint arthroplasty (TJA) candidates resulting in comorbid patients being taken care of in fewer hospitals. We aimed to (1) evaluate hospital-specific TJA comorbidity burden ("casemix") over time and (2) associations with resource utilization. METHODS: This retrospective cohort study used 2011 and 2016 New York State data (n = 36,078 hip/knee arthroplasties). Comorbidity burden was estimated by the Charlson-Deyo Index; main outcomes were hospitalization cost and nonhome discharge. Hospitals were categorized into those with a decreased, stable (with a 5% buffer), or increased percentage of comorbidity-free patients (Charlson-Deyo = 0) between 2011 and 2016. Mixed-effects models measured the association between Charlson-Deyo Index category and outcomes, by hospital casemix categorization. Odds ratios and 95% confidence intervals (CIs) are reported. RESULTS: Overall, 29 (n = 8810), 37 (n = 16,297), and 46 (n = 10,971) hospitals were categorized into the decreased, stable, and increased Charlson-Deyo = 0 categories, respectively, with median annual TJA volumes of 499, 814, and 393 (P < .0001). Multivariable models demonstrated that-in hospitals with a stable patient casemix-increased patient comorbidity was associated with increased hospitalization costs (maximum 21.8%, CI 18.9-24.9, P < .0001). However, this effect was moderated (maximum 11.1%, CI 8.0-14.2) in hospitals that took on a more comorbid patient casemix. Similar patterns were observed for nonhome discharge. CONCLUSION: Most studied hospitals show an increase in comorbidity-free TJA patients, suggestive of patient selection. This redistribution of comorbid patients to select hospitals may not necessarily be a negative development as our results suggest more efficient resource utilization for comorbid patients in such hospitals.

Are Histological Examinations of Arthroplasty Specimens Performed Consistently Across the Country? A Large Database Study.

BACKGROUND: It is currently unknown to what extent routine histological examination of joint arthroplasty specimens occurs across hospitals nationwide. Although this practice is neither supported nor refuted by the available evidence, given the increasing demand for joint arthroplasties, it is crucial to study overall utilization as well as its main drivers. QUESTIONS/PURPOSES: Using national data on joint replacements, we aimed to evaluate: (1) What is the current use of routine histological examination of joint arthroplasty specimens? (2) Does the use vary by geographic location and hospital characteristics? (3) Has use changed over time? METHODS: From the Premier Healthcare database (2006-2016) we included claims data from 87,667 shoulder (595 hospitals, median age 70 years, 16% nonwhite), 564,577 hip (629 hospitals, median age 65 years, 21% nonwhite), and 1,131,323 (630 hospitals, median age 66 years, 24% nonwhite) knee arthroplasties (all elective). Our study group has extensive experience with this data set, which contains information on 20% to 25% of all US hospitalizations. Included hospitals are mainly concentrated in the South (approximately 40%) with equal distributions among the Northeast, West, and Midwest (approximately 20% each). Moreover, the Premier data set has detailed billing information, which allows for evaluations of real-world clinical practice. There was no missing information on the main variables of interest for this specific study. We assessed frequency of histology examination (defined by Current Procedural Terminology codes) overall as well as by hospital characteristics (urban/rural, bed size, teaching status, arthroplasty volume), geographic region (Northeast, South, Midwest, West), and year. Given the large sample size, instead of p values, standardized differences were applied in assessing group differences where a standardized difference of > 0.1 (or 10%) was assumed to represent a meaningful difference between groups. For significance of trends, p values were applied. Percentages provided represent proportions of individual procedures. RESULTS: In most hospitals, histology testing was either rare (1%-10%, used in 187 of 595, 189 of 629, and 254 of 630 hospitals) or ubiquitous (91%-100%, used in 121 of 595, 220 of 629, and 195 of 630 hospitals) for shoulder, hip, and knee arthroplasties, respectively. Overall, histology testing occurred more often in smaller hospitals (37%-53% compared with 26%-45% in larger hospitals) and those located in the Northeast (59%-68% compared with 22%-44% in other regions) and urban areas (32%-49% compared with 20%-31% in rural areas), all with standardized differences > 10%. Histologic examination is slowly decreasing over time: from 2006 to 2016, it decreased from 34% to 30% for shoulder arthroplasty, from 50% to 45% for THAs, and from 43% to 38% for TKAs (all p < 0.001). CONCLUSIONS: Although overall use is decreasing, a substantial number of hospitals still routinely perform histology testing of arthroplasty specimens. Moreover, variation between regions and hospital types suggests that this practice is driven by a variety of factors. This is the first study addressing national utilization, which will be helpful for individual hospitals to assess how they compare with national utilization patterns. Moreover, the findings have clear implications for followup studies, which may be necessary given the exponentially growing demand for arthroplasties. LEVEL OF EVIDENCE: Level III, therapeutic study.

Drain Use is Associated with Increased Odds of Blood Transfusion in Total Shoulder Arthroplasty: A Population-Based Study.

BACKGROUND: In the absence of evidence supporting its benefit, the American Academy of Orthopaedic Surgeons (AAOS) strongly recommends against closed wound drainage in TKA; however, drain usage remains common in other joints, including the shoulder. While an extensive body of research exists for drain use in lower extremity joint arthroplasty, large-scale data on drain use and its association with benefits and complications in shoulder arthroplasties is lacking. Such data may be particularly valuable given the rapidly increasing demand for shoulder arthroplasties. QUESTION/PURPOSE: Using national claims data, we (1) evaluated the trends in frequency of drain usage in shoulder arthroplasty procedures over time, as well as the association between drain usage and (2) blood transfusion usage, (3) length of stay (LOS), and (4) readmission or early infection within 30 days. METHODS: This retrospective study used data from the nationwide Premier Healthcare claims database (2006-2016; n = 105,116, including total, reverse, and partial shoulder arthroplasties, in which drains were used in 20% [20,886] and no drain was used in 80% [84,230]). Included hospitals were mainly concentrated in the South (approximately 40%) with equal distributions among the Northeast, West, and Midwest (approximately 20% each). The Premier database contains detailed inpatient billing data on approximately 20% to 25% of US hospital discharges, which allows the creation of a variable indicating drain use by evaluating inpatient billing for drains. Baseline demographics differed minimally between patients receiving a drain compared with those who did not, with a median age of 70 years in both groups. The potential for selection bias was addressed by adjusting for measured confounders in mixed-effects models that estimated associations between drain use and blood transfusion usage, LOS, and readmission or (early) infection within 30 days. In addition, alternative statistical approaches were applied to address confounding, including propensity score analysis and instrumental variable analysis where a so-called "instrumental variable" is applied that mimics the treatment assignment process similar to a randomized study. We report odds ratios (OR; or % change for continuous variables) and 95% confidence intervals (CIs). RESULTS: The usage of drains decreased over time, from 1106 of 4503 (25%) in 2006 to 2278 of 14,501 (16%) in 2016. After adjusting for relevant covariates, drain use was associated with an increased usage of blood transfusions (OR, 1.49; 95% CI, 1.35-1.65; p < 0.001) while only associated with a small increase in LOS (+6%, 95% CI, +4% to +7%; p < 0.001). Drain use was not associated with increased odds for early postoperative infection or 30-day readmission. Propensity score analysis and instrumental variable analysis corroborated our main results. CONCLUSIONS: Use of drains in patients undergoing shoulder arthroplasty is associated with an almost 50% increased odds for blood transfusions. Given that our findings parallel close to what is known in patients undergoing lower extremity joint arthroplasty, we believe that our results from a large national database are sufficient to discourage the routine use of drains in patients undergoing shoulder arthroplasty. LEVEL OF EVIDENCE: Level III, therapeutic study.

Editorial Commentary: Open Versus Arthroscopic Elbow Osteocapsular Arthroplasty.

Elbow osteoarthritis is a difficult clinical problem. As it is characterized primarily by osteophyte formation, it seems that simple removal of those osteophytes, release of the capsule, and removal of loose bodies would suffice to restore a normal range of motion. However, unfortunately, this is not always the case. Open and arthroscopic treatment yields similar results in experienced hands, but patients may have some degree of recurrence or motion loss. To improve outcomes, release of the posterior band of the medial collateral ligament and transposition of the ulnar nerve could be thoughtfully considered.

Defining and Optimizing Value in Total Joint Arthroplasty From the Patient, Payer, and Provider Perspectives.

BACKGROUND: The purpose of this study is to define value in bundled total joint arthroplasty (TJA) from the differing perspectives of the patient, payer/employer, and hospital/provider. METHODS: Demographic, psychosocial, clinical, financial, and patient-reported outcomes (PROs) data from 2017 to 2018 elective TJA cases at a multihospital academic health system were queried. Value was defined as improvement in PROs (preoperatively to 1 year postoperatively) for patients, improvement in PROs per $1000 of bundle cost for payers, and the normalized sum of improvement in PROs and hospital bundle margin for providers. Bivariate analysis was used to compare high value vs low value (>50th percentile vs <50th percentile). Multivariate analysis was performed to identify predictors. RESULTS: A total of 280 patients had PRO data, of which 71 had Medicare claims data. Diabetes (odds ratio [OR], 0.45; P = .02) predicted low value for patients; female gender (OR, 0.25), hypertension (OR, 0.17), pulmonary disease (OR, 0.12), and skilled nursing facility discharge (OR, 0.17) for payers (P ≤ .03 for all); and pulmonary disease (OR, 0.16) and skilled nursing facility discharge (OR, 0.19) for providers (P ≤ .04 for all). CONCLUSION: This is the first article to define value in TJA under a bundle payment model from multiple perspectives, providing a foundation for future studies analyzing value-based TJA.