International trends in shoulder replacement: a meta-analysis from 11 public joint registers.

BACKGROUND AND PURPOSE: International variation exists in the types of shoulder replacement used for treatment of specific diseases. Implant choice continues to evolve without high-quality evidence. Our aim was to evaluate trends in incidence rates of shoulder replacement and assess any recent changes in practice between countries by using registry data. METHODS: Patient characteristics, indication and year of surgery, type of replacement, and collection methods of patient-reported outcomes (PROMs) was extracted from 11 public joint registries. Meta-analyses examined use of reverse total shoulder replacement (RTSR) for osteoarthritis, cuff tear arthropathy, and acute fracture; use of anatomical total shoulder replacement (TSR) for osteoarthritis; and use of humeral hemiarthroplasty for fracture. RESULTS: The annual growth rate of shoulder replacements performed is 6-15% (2011-2019). The use of RTSR has almost doubled (93%). RTSR is now universally performed for cuff tear arthropathy (97.3%, 95% confidence interval [CI] 96.0-98.1). Its use for avascular necrosis, trauma, and inflammatory arthropathy is increasing. The use of RTSR was similar (43.1%, CI 30.0-57.2) versus TSR (44.7%, CI 31.1-59.1) for osteoarthritis. The types of PROMs used, collection time points, and response rates lack standardization. COVID-19 had a varying inter-registry impact on incidence rates. CONCLUSION: The incidence of shoulder replacements has grown. Use of RTSR has increased for all disease indications despite limited high-quality evidence driving this change in indications outside of cuff arthropathy. Consequently, less variation is observed in international practice. Existing differences now relate to use of newer implant types and methodology of PROMs collection, which prevents international comparison and outcome analysis.

Gender differences among shoulder arthroplasty surgeons: past, present, and future.

BACKGROUND: Reducing differences in the gender representation of shoulder arthroplasty surgeons may help optimize patient care. This work aimed to determine (1) the current gender distribution of surgeons performing shoulder arthroplasty, (2) how gender relates to practice patterns among shoulder arthroplasty surgeons, and (3) how gender distribution has been changing over time. METHODS: The Medicare Provider Utilization and Payment Data for the years 2012-2020 were used to identify orthopedic surgeons performing anatomic and reverse total shoulder arthroplasty (Current Procedural Terminology code 23472). The data set provides self-reported gender, credentials, National Provider Identifier, annual volume of all procedures (based on Current Procedural Terminology codes) that were performed ≥11 times in the calendar year, and location for all included providers. The data set was linked to the Medicare Physician Compare data set using National Provider Identifiers to determine hospital affiliations, year of medical school graduation, and graduating medical school. All included hospitals were queried to determine academic status (affiliated orthopedic residency or fellowship program). The American Shoulder and Elbow Surgeons (ASES) directory was reviewed to determine the gender breakdown of current members. RESULTS: The number of surgeons performing ≥11 shoulder arthroplasties annually increased from 821 (13 women [1.6%]) in 2012 to 1840 (53 women [2.9%], P = .05) in 2019. One female surgeon ranked in the top 100 surgeons by shoulder arthroplasty volume in 2012 and in 2020. Female surgeons graduated more recently from medical school (mean, 2005) compared with male surgeons (mean, 1997; P < .001). About 10% of female surgeons (10.8%, 12 of 111) and male surgeons (9.1%, 229 of 2528) practiced at hospitals with orthopedic residents (P = .50). Female surgeons performing shoulder arthroplasty were less likely than male surgeons to perform total knee arthroplasty (29.4% vs. 54.1%, P < .001) and total hip arthroplasty (12.6% vs. 34.7%, P < .001). There were 86 female members of ASES (6.7%, 86 of 1275), with a significant difference in the proportion of women in differing membership categories (P = .017). DISCUSSION AND CONCLUSION: A diverse cohort of high-volume shoulder replacement surgeons is integral to delivering high-quality shoulder arthroplasty. Currently, the proportion of women performing high-volume shoulder replacement in the United States is small, with little improvement in recent years. However, women performing shoulder arthroplasty are younger and are often involved in academic practices, and the membership of ASES is increasingly female. Continued efforts to promote orthopedics-and to mentor female residents and medical students interested in shoulder surgery-may bring real change to the gender differences among shoulder replacement surgeons over the coming years.

No change in reoperation rates despite shifting treatment trends: a population-based study of 4,070 proximal humeral fractures.

Background and purpose - Clear and acknowledged treatment algorithms for proximal humeral fractures (PHFs) are lacking. Nevertheless, a change in treatment trends, including a change towards more reversed shoulder arthroplasties (RSA), has been observed during recent years. We examined the effect of these changes on reoperation rates.Patients and methods - Between 2011 and 2017, 4,070 PHFs treated at Sahlgrenska University Hospital were registered prospectively in the Swedish Fracture Register (SFR) and followed up until 2019 (mean follow-up of 4.5 years). Data on all reoperations were gathered from the SFR and from medical records.Results - The majority of PHFs were treated non-surgically and the proportion increased slightly, but not statistically significantly, during the study period (from 76% to 79%). Of the surgically treated fractures, the proportion fixed with a plate decreased from 47% to 25%, while the use of RSA increased 9-fold (from 2.0% to 19%). 221 patients underwent 302 reoperations. For those primarily treated surgically, the reoperation rate was 17%. Among treatment modalities, plate fixation was associated with the highest reoperation rate (21%). Rate of reoperations remained constant during the study period, both for the entire study cohort and for the surgically treated patientsInterpretation - During the study period, treatment changes that are in accordance with recently published treatment recommendations were observed. However, these treatment changes did not affect the reoperation rate. Treatment with a plate, intramedullary nail, or hemiarthroplasty was associated with the highest reoperation rates. The fact that almost every 4th surgical procedure was a reoperation indicates a need for further improvement of modern treatment concepts for PHFs.

Lifetime Risk of Primary Shoulder Arthroplasty From 2008 to 2017: A Population-Level Analysis Using National Registry Data.

OBJECTIVE: To estimate the lifetime risk of primary shoulder arthroplasty in Australia and to examine changes over time. METHODS: For this retrospective population-level analysis, de-identified individual-level data on all primary partial shoulder arthroplasty (PSA) and total shoulder arthroplasty (TSA) procedures performed in Australia from 2008 to 2017 (n = 38,868) were obtained from the Australian Orthopaedic Association National Joint Replacement Registry. Population data and life tables were obtained from the Australian Bureau of Statistics. Lifetime risk of primary shoulder arthroplasty was calculated for each year using a standardized formula. Separate calculations were undertaken by sex and for PSA and TSA. RESULTS: The lifetime risk of shoulder arthroplasty increased significantly over time. For men, this risk more than doubled from 0.78% (95% confidence interval [95% CI] 0.73-0.84) in 2008 to 1.78% (95% CI 1.70-1.86) in 2017. Lifetime risk for women rose from 1.54% (95% CI 1.46-1.62) to 2.88% (95% CI 2.78-2.99) over the study period. This increase was predominantly driven by growth in lifetime risk of TSA. In contrast, lifetime risk of PSA decreased over time, from 0.25% (95% CI 0.22-0.28) in 2008 to 0.11% (95% CI 0.09-0.13) in 2017 for men, and from 0.55% (95% CI 0.51-0.60) to 0.11% (95% CI 0.09-0.13) for women. CONCLUSION: By the end of 2017, the lifetime risk of primary shoulder arthroplasty in Australia increased to 1 in 57 for men and 1 in 35 for women. Compared to declining PSA trends, there was substantial growth in TSA use over a decade. These data improve our understanding of the rising national burden of primary shoulder arthroplasty and can assist in planning to meet future surgical demand.

The incidence of shoulder arthroplasty: rise and future projections compared with hip and knee arthroplasty.

BACKGROUND: There remains a paucity of epidemiologic data from recent years on the incidence of shoulder arthroplasty. We aimed to examine the recent trends and predict future projections of hemiarthroplasty (HA), anatomic (aTSA), and reverse shoulder arthroplasty (RSA), as well as compare these predictions to those for total hip (THA) and knee arthroplasty (TKA). METHODS: The National Inpatient Sample was queried from 2011 to 2017 for HA, aTSA, and RSA, as well as TKA and THA. Linear and Poisson regression was performed to project annual procedural incidence and volume to the year 2025. RESULTS: Between 2011 and 2017, the number of primary shoulder arthroplasties increased by 103.7%. In particular, RSA increased by 191.3%, with 63,845 RSAs performed in 2017. All projection models demonstrated significant increases in shoulder arthroplasty volume and incidence from 2017 to 2025. By 2025, the linear model predicts that shoulder arthroplasty volume will increase by 67.2% to 174,810 procedures whereas the Poisson model predicts a 235.2% increase, to 350,558 procedures by 2025. These growth rate projections outpace those of THA and TKA. CONCLUSIONS: The number of shoulder arthroplasties has been increasing in recent years, largely because of the exponential increases in RSA. The overall incidence is increasing at a greater rate than TKA or THA, with projections continuing to rise over the next decade. These data and projections can be used by policy makers and hospitals to drive initiatives aimed at meeting these projected future demands.

National Trends in the Surgical Treatment of Chronic Rotator Cuff Tear in Patients Without Arthritis.

Both rotator cuff repair (RCR) and reverse total shoulder arthroplasty (RTSA) are effective treatment options for chronic large degenerative rotator cuff tear (RCT) in the elderly. The goal of this study was to evaluate national trends for surgical management of chronic RCT among patients without glenohumeral arthritis. The authors conducted a retrospective review from 2007 to 2015 using the PearlDiver database. The study included patients who had the International Classification of Diseases, Ninth Revision, diagnosis of chronic RCT without shoulder arthritis. Procedural codes from the Current Procedural Terminology and the International Classification of Diseases, Ninth Revision, were used to identify patients undergoing RCR or RTSA. Chi-square analysis assessed differences between the groups, and Cochran-Armitage trend tests were used to evaluate trends over time. Overall, 428,651 patients had chronic RCT without arthritis; 364,141 (84.9%) were treated nonoperatively, 53,566 (12.5%) underwent RCR, and 10,944 (2.6%) underwent RTSA. Patients who were 60 to 79 years old had the highest rate of surgical intervention (70.8% of all surgical patients), with 69.2% and 78.4% who underwent RCR and RTSA, respectively. A 3-fold increase in RTSA use was noted among patients 60 years and older vs patients younger than 60 years. Overall revision rates 2 years after RCR and RTSA among patients 60 to 79 years old were 13.0% and 3.7%, respectively. Revision rates after RCR remained constant over time (9.3% to 13.0%; P=.082), whereas revision rates after RTSA decreased significantly over time (12.1% to 2.2%; P=.016). Older patients were more likely to be treated nonoperatively compared with younger patients, but among those patients treated with RTSA, there was a 3-fold increase in the use of RTSA in patients older than 60 years compared with patients younger than 60 years. Further, the authors found that revision rates after RTSA decreased over time (from 12% to 2%), suggesting better implant design, improved knowledge of implant positioning, and increased surgical proficiency. [Orthopedics. 2020;43(5):e409-e414.].

Cemented vs. uncemented glenoid fixation in total shoulder arthroplasty for osteoarthritis: a New Zealand Joint Registry study.

BACKGROUND: Total shoulder arthroplasty (TSA) is commonly performed for shoulder osteoarthritis (OA). Uncemented metal-backed (MB) glenoid components were introduced in an attempt to avoid glenoid loosening. New Zealand and Australian Joint Registry studies have shown significantly higher revision rates when uncemented MB glenoids are used. We used the New Zealand Joint Registry (NZJR) to compare all-cause revision rates and functional scores for TSA and investigated the trends of glenoid fixation used in New Zealand. METHODS: The NZJR was accessed for all primary TSA undertaken for OA from January 2000 to December 2017. Patient demographics were collated. All-cause revision rates were reported as rate per 100 component-years. Analysis was repeated excluding the uncemented SMR L2 glenoid (LimaCorporate), as it was a potential confounder. Kaplan-Meier survival analysis was performed. Oxford Shoulder Scores at both 6 months and 5 years were analyzed. RESULTS: A total of 2613 TSAs were performed for OA during the study period, representing 85.0% of all TSAs in New Zealand. Overall, 62.1% of the patients were female. In addition, 69.6% of glenoids were cemented and 30.4% uncemented. The most common uncemented MB glenoid was SMR 86.6% (LimaCorporate), and cemented was Global (DePuy) 49.8%. The revision rate for TSA with uncemented glenoids was significantly higher at 2.03 compared with cemented at 0.41 per 100 component-years (P < .001). Hazard ratio 5.0 for revision of uncemented glenoids. No significant difference was found in Oxford Scores at 6 months (39.7 vs. 40.3, P = .13) or 5 years (42.1 vs. 42.8, P = .22). The most common mode of failure was glenoid loosening in cemented glenoids (44.4%), and component failure in uncemented (34.8%). Revision for rotator cuff, deep infection, and instability were comparable between groups. When excluding SMR L2, uncemented MB glenoid all-cause revision rates remained significantly higher than cemented (1.42 vs. 0.41 per 100 component-years, P < .001). SMR L1 uncemented MB glenoids had a higher revision rate than the non-SMR uncemented glenoids (1.61 vs. 0.18 per 100 component-years, P = .009). Uncemented glenoid use peaked in New Zealand in 2011 at 46.7% of TSAs but declined to 20.1% in 2017. CONCLUSIONS: In the NZJR, primary TSAs undertaken for OA have a significantly higher all-cause revision rate when the glenoid component is uncemented. Uncemented glenoids have a 5.0 times higher revision rate. Excluding SMR L2 glenoids from the analysis, the significantly higher revision rate remained for uncemented glenoids. These data reaffirm that uncemented MB glenoids are associated with higher revision rates.

Loosening and revision rates after total shoulder arthroplasty: a systematic review of cemented all-polyethylene glenoid and three modern designs of metal-backed glenoid.

BACKGROUND: Several modern designs of metal-backed glenoids (MBG) have been devised to overcome flaws such as loosening and a high failure rate. This review aimed to compare rates of complications and revision surgeries between cemented polyethylene glenoid (PEG) and three examples of modern MBG designs. METHODS: Literature search was carried out using PubMed, Cochrane Library, EMBASE, and Google Scholar using MeSH terms and natural keywords. A total of 1186 articles were screened. We descriptively analyzed numerical data between the groups and statistically analyzed the categorical data, such as the presence of radiolucent line, loosening, and revision surgery (failure). Articles were divided into three groups based on follow-up duration: < 36-month, 36-72-month, and > 72-month subgroups. RESULTS: This study included 35 articles (3769 shoulders); 25 on cemented PEG and ten on the modern MBG. Mean age was 66.4 (21-93) and 66.5 years (31-88). The mean duration of follow-up was 73.1 (12-211) and 56.1 months (24-100). Overall, the rate of the radiolucent line was 354/1302 (27%) and 47/282 (17%), the loosening rate was 465/3185 (15%) and 22/449 (5%), and the failure rate was 189/3316 (6%) and 11/457 (2%), for PEG and MBG, respectively. The results of < 36-month and 36-72-month subgroups showed lower rates of radiolucency and loosening in the cemented PEG group, but there was no significant difference in failure rate (P = 0.754 and 0.829, respectively). In the > 72-month subgroup, MBG was better in terms of loosening (P < 0.001) and failure rates (P = 0.006). CONCLUSIONS: The modern MBG component, especially TM glenoid, seems to be a promising alternative to cemented PEGs, based on subgroup revision rates according to the follow-up duration and overall results of ROM and clinical scores. All polyethylene glenoids tend to increase loosening and failure over time. Three modern MBG designs seem to have no difference in failure, at least in the < 36-month and 36-72-month subgroups compared to the cemented PEG. More long-term follow-up studies on modern MBG should be ultimately conducted. LEVEL OF EVIDENCE: Level IV, systematic review.

Increased use of total shoulder arthroplasty for osteoarthritis and improved patient-reported outcome in Denmark, 2006-2015: a nationwide cohort study from the Danish Shoulder Arthroplasty Registry.

Background and purpose - Osteoarthritis has become the most common indication for shoulder arthroplasty in Denmark, and the treatment strategies have changed towards the use of anatomical total shoulder arthroplasty and reverse shoulder arthroplasty. We investigated whether changes in the use of arthroplasty types have changed the overall patient-reported outcome from 2006 to 2015. Patients and methods - We included 2,867 shoulder arthroplasties performed for osteoarthritis between 2006 and 2015 and reported to the Danish Shoulder Arthroplasty Registry. The Western Ontario Osteoarthritis of the Shoulder (WOOS) index at 1 year was used as patient-reported outcome. The raw score was converted to a percentage of a maximum score. General linear models were used to analyze differences in WOOS. Results - The proportion of anatomical total shoulder arthroplasty and reverse shoulder arthroplasty increased from 3% and 7% in 2006 to 53% and 27% in 2015. The mean WOOS score was 70 (SD 26) after resurfacing hemiarthroplasties (n = 1,258), 68 (SD 26) after stemmed hemiarthroplasty (n = 500), 82 (SD 23) after anatomical total shoulder arthroplasties (n = 815), and 74 (SD 23) after reverse shoulder arthroplasties (n = 213). During the study period, the overall WOOS score increased with 18 (95% CI 12-22) in the univariate model and 10 (CI 5-15) in the multivariable model, and the WOOS scores for anatomical total shoulder arthroplasty increased by 14 (CI 5-23). Interpretation - We found an increased WOOS score from 2006 to 2015, which was primarily related to a higher proportion of anatomical total shoulder arthroplasty and reverse shoulder arthroplasty towards the end of the study period, and to improved outcome of anatomical total shoulder arthroplasty.

Surgical trends in elderly patients with proximal humeral fractures in South Korea: a population-based study.

BACKGROUND: It is known that there are large regional variations in treatment methods for the management of proximal humeral fractures. The objective of this study was to investigate the national surgical trends in elderly patients with proximal humeral fractures in South Korea. METHODS: We analyzed the Korean Health Insurance Review and Assessment Service database from 2008 to 2016. International Classification of Diseases, 10th revision codes and procedure codes were used to identify patients aged ≥65 years with proximal humeral fractures. RESULTS: A total of 69,120 proximal humeral fractures were identified from 2008 to 2016. The overall operative rate for proximal humeral fractures increased steadily from 24.6% in 2008 to 36.8% in 2016 (p < 0.001). The rate of cases treated with open reduction and internal fixation tended to increase each year, from 71.5% of the overall surgeries in 2008 to 85.6% in 2016; conversely, the rate of cases treated with closed reduction and internal fixation tended to decrease from 19.9% in 2008 to 4.5% in 2016. In terms of type of arthroplasty procedure, the rate of cases treated with reverse shoulder arthroplasty tended to increase significantly each year, from 8.2% of the overall arthroplasty procedures in 2008 to 52.0% in 2016 (p < 0.001). The proportion of reverse shoulder arthroplasty was shown to increase especially in patients aged 80 years or older. CONCLUSION: Overall, our findings indicated that surgical treatment of proximal humeral fractures, particularly by open reduction and internal fixation, continues to increase; in terms of type of arthroplasty procedure, the rate of cases treated with reverse shoulder arthroplasty tended to increase.

The increasing role of reverse total shoulder arthroplasty in the treatment of proximal humerus fractures.

INTRODUCTION: Hemiarthroplasty of the shoulder is a well established treatment for proximal humerus fractures not amenable to open reduction internal fixation. However, orthopedic surgeons have recently increased utilization of reverse total shoulder arthroplasty (RTSA) in the treatment of these injuries. The purpose of this study was to evaluate the use of hemiarthroplasty and RTSA between 2009 and 2016 for the treatment of proximal humerus fractures within a large United States integrated healthcare system. MATERIALS AND METHODS: A descriptive study was conducted using our integrated healthcare system's Shoulder Arthroplasty Registry. Shoulder arthroplasty cases performed for an acute proximal humerus fracture between the years of 2009 and 2016 were identified. Revision rates were determined, as well as changes in age and gender distribution of the cohort during the study period. RESULTS: In 2015, RTSA utilization surpassed that of hemiarthroplasty for the first time in the healthcare system. The utilization of RTSA in the treatment of proximal humerus fractures increased from 4.5% of all arthroplasties in 2009 to 67.4% of arthroplasties in 2016. During the study period, patients undergoing hemiarthroplasty were younger and less likely to be female. Crude revision rate was 4.0% for hemiarthroplasty and 3.2% for RTSA. CONCLUSIONS: RTSA is increasingly being utilized for the treatment of proximal humerus fractures and now appears to be the treatment of choice. While hemiarthroplasty appears to be falling out of favor in the treatment of fractures of the shoulder, surgeons may still be preferentially using the procedure in younger patients.

Medicaid payer status is associated with increased mortality and morbidity after inpatient shoulder arthroplasty: a multistate analysis, 2007-2014.

BACKGROUND AND OBJECTIVES: Inpatient shoulder arthroplasty is widely performed around the USA at an increasing rate. Medicaid insurance has been identified as a risk factor for inferior surgical outcomes. We sought to identify the impact of being Medicaid-insured on in-hospital mortality, readmission, complications, and length of stay (LOS) in patients who underwent inpatient shoulder arthroplasty. METHODS: We analyzed 89 460 patient discharge records for inpatient total, partial, and reverse shoulder arthroplasties using data from the Healthcare Cost and Utilization Project's State Inpatient Databases for California, Florida, New York, Maryland, and Kentucky from 2007 through 2014. We compared patient demographics, present-on-admission comorbidities, and hospital characteristics by insurance payer. We estimated multilevel mixed-effect multivariate logistic regression models and generalized linear models to assess insurance's effect on in-hospital mortality, readmission, infectious complications, cardiac complications, and LOS; models controlled for patient and hospital characteristics. RESULTS: Medicaid-insured patients had greater odds than patients with private insurance, other insurance, and Medicare of inpatient mortality (OR: 4.61, 95% CI 2.18 to 9.73, p<0.001) and 30-day and 90-day readmissions (OR: 1.94, 95% CI 1.57 to 2.38, p<0.001; OR: 1.65, 95% CI 1.42 to 2.38, p<0.001, respectively). Compared with private insurance, other insurance, and Medicare patients, Medicaid patients had increased likelihood of developing infectious complications and were expected to have longer LOS. CONCLUSIONS: Our study supports our hypothesis that among inpatient shoulder arthroplasty patients, those with Medicaid insurance have worse outcomes than patients with private insurance, other insurance, and Medicare. These results are relatively consistent with previous findings in the literature.

Is arthroscopic repair superior to biceps tenotomy and tenodesis for type II SLAP lesions? A meta-analysis of RCTs and observational studies.

OBJECTIVE: Labral repair and biceps tenotomy and tenodesis are routine operations for type II superior labrum anterior posterior (SLAP) lesion of the shoulder, but evidence of their superiority is lacking. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic repair versus biceps tenotomy and tenodesis intervention. METHODS: The eight studies were acquired from PubMed, Medline, Embase, CNKI, and Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed by RevMan 5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle-Ottawa Scale were used to assess risk of bias. RESULTS: Eight studies including two randomized controlled trials (RCTs) and six observational studies were assessed. The methodological quality of the trials ranged from low to moderate. The pooled results of UCLA score, SST score, and complications showed that the differences were not statistically significant between the two interventions. The difference of ASES score and satisfaction rate was statistically significant between arthroscopic repair and biceps tenotomy and tenodesis intervention, and arthroscopic biceps tenotomy and tenodesis treatment was more effective. Sensitivity analysis proved the stability of the pooled results, and there were too less included articles to verify the publication bias. CONCLUSIONS: Both arthroscopic repair and biceps tenotomy and tenodesis interventions had benefits in type II SLAP lesions. Arthroscopic biceps tenotomy and tenodesis treatment provides better clinical outcome in ASES score and satisfaction rate and comparable complications compared with arthroscopic repair treatment. In view of the heterogeneity and confounding factors, whether these conclusions are applicable should be further determined in future studies.

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.

Clinical outcomes and complications of cementless reverse total shoulder arthroplasty during the early learning curve period.

BACKGROUND: Reverse total shoulder arthroplasty (RTSA) is a treatment option for patients with severe osteoarthritis, rotator cuff arthropathy, or massive rotator cuff tear with pseudoparalysis. We are to deduce not only the early functional outcomes and complications of cementless RTSA during the learning curve period but also complication-based, and operation time-based learning curve of RTSA. METHODS: Between March 2010 and February 2014, we retrospectively evaluated 38 shoulders (6 male, 32 female). The average age of the patients was 73.0 years (range, 63 to 83 years), and the average follow-up was at 24 months (range, 12-53 months). The visual analog scale (VAS), University of California Los Angeles (UCLA) score and constant score were used to evaluate the clinical outcomes. We evaluated patients radiographically at 2 weeks, 3 months, 6 months, 1 year, and then annually thereafter for any evidence of complications. RESULTS: The VAS score improved from 4.0 to 2.8 (p = 0.013). The UCLA score improved from 16.0 to 27.9 (p = 0.002), and the constant score improved from 41.4 to 78.9 (p < 0.001), which were statistically significant. While active forward flexion, abduction, and internal rotation improved (p value = 0.001, < 0.01, 0.15), external rotation did not show significant improvement (p = 0.764). Postoperative complications included acromion fracture (one case), glenoid fracture (one case), peripristhetic humeral fracture (one case), axillary nerve injury (one case), infection (one case), and arterial injury (one case). Our study presented an intraoperative complication-based learning curve of 20 shoulders, and operation time-based learning curve of 15 shoulders. CONCLUSIONS: The clinical outcomes of RTSA were satisfactory with overall complication rates of 15.7%. An orthopedic surgeon within the learning curve period for the operation of RTSA should be cautious when selecting the patients and performing RTSA. TRIAL REGISTRATION: Retrospectively registered.

Early postoperative complications and discharge time in diabetic patients undergoing total shoulder arthroplasty.

PURPOSE: With the increasing elderly population and obesity epidemic, diabetes is an important factor in arthroplasty planning. Although research suggests diabetes is associated with increased postoperative morbidity after hip and knee replacement, the effect of diabetes and varying management with insulin versus non-insulin agents on total shoulder arthroplasty (TSA) is not established. METHODS: All TSAs from 2015 to 2016 were queried from the American College of Surgeons National Surgical Quality Improvement Program database. Age, gender, BMI, steroid, ASA, operative time, and smoking status were compared between all diabetics, diabetics on insulin, diabetics on non-insulin agents, and non-diabetics to account for confounding variables. Thirty-day postoperative complications, readmission rate, surgical site infection (SSI), and non-routine discharge to rehabilitation were compared using bivariate and multivariate binary logistic regression. Postoperative time to discharge between diabetic groups was analyzed using univariate ANOVA with Tukey's test. RESULTS: The analysis included 7246 patients (insulin in 5% (n = 380), non-insulin in 13% (n = 922), and non-diabetics in 82% (n = 5944)). Diabetics were more likely to have an ASA ≥ 3 compared to non-diabetics (89.5% vs 50.1%; p < 0.001). Bivariate logistic regression showed statistical significance in readmission and non-routine discharge between all diabetics and non-diabetics (OR 1.7, 1.4; p = 0.001, 0.001), but there was no significance between SSI rate (0.3% vs 0.4%; p = 0.924). Multivariate logistic regression between groups showed significance in readmission between non-insulin diabetics vs non-diabetics (OR 1.5; p = 0.027), readmission and non-routine discharge in insulin vs non-diabetics (OR 2.1, 1.7; p = 0.003, < 0.001), and no significance between insulin and non-insulin diabetics. Postoperative days to discharge were 2.4, 2.0, and 1.8 days in insulin, non-insulin, and non-diabetics respectively. Mean differences were significant between all groups. CONCLUSIONS: Diabetic patients are at a higher risk for readmission and non-routine discharge compared to non-diabetics. Despite no increased risk in SSI, longer postoperative discharge time in diabetics should be considered in TSA planning. TRIAL REGISTRATION: Not applicable LEVEL OF EVIDENCE: Level III, case-control study.

The impact of the reverse prosthesis on revision shoulder arthroplasty: analysis of a high-volume shoulder practice.

BACKGROUND: Since the approval of reverse shoulder arthroplasty (RSA) in 2004, the use of shoulder arthroplasty increased dramatically. Although the success of RSA in the revision setting has been demonstrated, there remains a paucity of studies examining the epidemiology of RSA in revision arthroplasty. This study describes trends of revision arthroplasty during the "era of the reverse," from 2005 through 2016. METHODS: In a multicenter retrospective analysis, we analyzed 274 revision shoulder arthroplasties converted to a RSA (n = 182), anatomic total shoulder arthroplasty (TSA, n = 68), or hemiarthroplasty (n = 24) from 2005 to 2016. Demographics, surgical indications, and types of prosthesis were analyzed. RESULTS: The number of revision arthroplasties increased over 12 years. From 2005 to 2010, TSA (33%) or hemiarthroplasty (16%) were used in similar rates as RSA (51%). From 2011 to 2016, there was a much higher incidence of revision arthroplasty with RSA (78%) compared with TSA (19%) or hemiarthroplasty (3%). Specifically, the number of RSAs increased in 2011 to 2016 compared with 2005 to 2010 in patients aged younger than 60 years, obese patients, patients with indications of glenoid loosening, and those with a diagnosis of diabetes mellitus or rheumatoid arthritis. CONCLUSIONS: The use of RSA for revision arthroplasty increased over the "era of the reverse" and became the majority by 2016. The reverse prosthesis has had expanding indications regarding both patient demographics and pathology. This study demonstrates the reverse prosthesis has had a similar and even more profound effect on revision shoulder arthroplasty than what has previously been well documented in the primary setting.

Reverse shoulder arthroplasty vs BIO-RSA: clinical and radiographic outcomes at short term follow-up.

BACKGROUND: Bony increased-offset reverse shoulder arthroplasty (BIO-RSA) may address issues such as inferior scapular notching, prosthetic instability and limited postoperative shoulder rotation; all of which have been reported with the standard RSA and attributed to the medialized design. We hypothesised that this lateralization may increase the rate of scapular stress fractures. METHODS: A retrospective review of prospectively collected data was performed on patients who had undergone a RSA between January 2013 and October 2016. A comparative cohort study was designed to compare patients with a standard Grammont-style RSA to those with a BIO-RSA using the same implant. Functional outcome was measured by the American Shoulder and Elbow Surgeons (ASES) Shoulder Score, the Subjective Shoulder Value (SSV), the Western Ontario Osteoarthritis of the Shoulder (WOOS) index and pain scores. Radiographs were obtained for all patients and examined for the presence of scapular fracture as well as scapular notching and graft incorporation. RESULTS: A total of forty patients (22 patients in the standard RSA cohort and 18 with BIO-RSA) were included in the study. Patient characteristics (including age, gender, length of follow-up, dominant side and osteoporosis) were similar in both groups (p > 0.05). The average postoperative follow-up was 20 months (range 12-48 months). There was bone graft incorporation in all BIO-RSA patients at the final radiological follow-up, with no evidence of graft resorption. The overall scapular stress fracture rate was 12.5% (9.1% in the standard RSA and 16.7% in the BIO-RSA). The rates were similar in both cohorts (p = 0.64). All fractures were managed conservatively. To determine whether the presence of a scapular stress fracture had an influence on outcomes, the cohort was divided into cases with and without fracture. Patients with a stress fracture had worse ASES (p = 0.028) and WOOS (p = 0.048) scores. Additionally, osteoporosis was present more commonly in the fracture group (80% vs 17%; p = 0.01). A statistically significant difference was identified when comparing the rates of scapular notching between standard RSA and BIO-RSA cohorts (68% vs 33%; p = 0.028). Furthermore, when notching was present, significantly worse outcome scores were present in all outcome measures (p < 0.001). CONCLUSION: The BIO-RSA technique was associated with an increase in scapular stress fracture rate when compared to the standard RSA; however, this was not found to be significant. Furthermore, both techniques resulted in similar improvements in the measured functional outcomes. BIO-RSA, however, was associated with a lower scapular notching rate, justifying further evaluation of this technique. LEVEL OF EVIDENCE: Retrospective cohort study, level III.

Minimum Clinically Important Difference: Current Trends in the Orthopaedic Literature, Part I: Upper Extremity: A Systematic Review.

BACKGROUND: The minimum clinically important difference (MCID) attempts to define the patient's experience of treatment outcomes. Efforts at calculating the MCID have yielded multiple and inconsistent MCID values. The purposes of this review were to describe the usage of the MCID in the most recent orthopaedic literature, to explain the limitations of its current uses, and to clarify the underpinnings of MCID calculation. Subsequently, we hope that the information presented here will help practitioners to better understand the MCID and to serve as a guide for future efforts to calculate the MCID. The first part of this review focuses on the upper-extremity orthopaedic literature. Part II will focus on the lower-extremity orthopaedic literature. METHODS: A review was conducted of the 2014 to 2016 publications in The Journal of Arthroplasty, The Journal of Bone & Joint Surgery, The American Journal of Sports Medicine, Foot & Ankle International, Journal of Orthopaedic Trauma, Journal of Pediatric Orthopaedics, and Journal of Shoulder and Elbow Surgery. Only clinical science articles utilizing patient-reported outcome measure (PROM) scores were included in the analysis. A keyword search was then performed to identify articles that calculated or referenced the MCID. Articles were then further categorized into upper-extremity and lower-extremity publications. MCID utilization in the selected articles was subsequently characterized and recorded. RESULTS: The MCID was referenced in 129 (7.5%) of 1,709 clinical science articles that utilized PROMs: 52 (40.3%) of 129 were related to the upper extremity, 5 (9.6%) of 52 independently calculated MCID values, and 47 (90.4%) of 52 used previously published MCID values as a gauge of their own results. MCID values were considered or calculated for 16 PROMs; 12 of these were specific to the upper extremity. Six different methods were used to calculate the MCID. Calculated MCIDs had a wide range of values for the same PROM (e.g., 8 to 36 points for Constant-Murley scores and 6.4 to 17 points for American Shoulder and Elbow Surgeons [ASES] scores). CONCLUSIONS: Determining useful MCID values remains elusive and is compounded by the proliferation of PROMs in the field of orthopaedics. The fundamentals of MCID calculation methods should be critically evaluated. If necessary, these methods should be corrected or abandoned. Furthermore, the type of change intended to be measured should be clarified: beneficial, detrimental, or small or large changes. There should also be assurance that the calculation method actually measures the intended change. Finally, the measurement error should consistently be reported. CLINICAL RELEVANCE: The MCID is increasingly used as a measure of patients' improvement. However, the MCID does not yet adequately capture the clinical importance of patients' improvement.

Increasing incidence of primary shoulder arthroplasty in Finland - a nationwide registry study.

BACKGROUND: The incidence of shoulder arthroplasties is reportedly increasing and the types of arthroplasty are changing. The purpose of this study was to investigate the incidence of primary shoulder arthroplasty in Finland. METHODS: We analyzed nationwide data from the Finnish Arthroplasty Register (FAR) and the Finnish National Hospital Discharge Register (NHDR) during time period 2004-2015. The primary outcome variable was the incidence of shoulder arthroplasty per 100,000 person-years stratified by age, sex and year of surgery. The secondary outcome variables were surgical indication, arthroplasty type and prosthesis model. RESULTS: The number of primary shoulder arthroplasties was 7504 (women = 4878, men = 2625). The rate of operations increased from 6 to 15 per 100,000 person-years among men, and 11 to 26 per 100,000 person-years among women. The indication for arthroplasty was osteoarthritis in 56%, acute fracture in 21%, inflammatory arthritis in 13%, and rotator cuff arthropathy in 4% of the cases. Hemiarthroplasties accounted for 66%, total shoulder arthroplasties 8%, and reverse shoulder arthroplasties 12% of the cases, 14% of the cases was missing. During the 12-year study period the incidence of hemiarthroplasties decreased by 23% and the number of total shoulder and reverse shoulder arthroplasty increased by 500 and 4500%, respectively. CONCLUSIONS: The incidence of primary shoulder arthroplasty has increased by 160% during the study period in Finland. The incidence of hemiarthroplasties decreased while total and reverse shoulder arthroplasties increased.