Factors predicting complication rates after primary shoulder arthroplasty

Risk of serious adverse events after primary shoulder replacement: development and external validation of a prediction model using linked national data from England and Denmark

BACKGROUND

Despite a rising rate of serious medical complications after shoulder replacement surgery, there are no prediction models in widespread use to guide surgeons in identifying patients at high risk and to provide patients with personalised risk estimates to support shared decision making. Our aim was to develop and externally validate a prediction model for serious adverse events within 90 days of primary shoulder replacement surgery.

METHODS

Linked data from the National Joint Registry, National Health Service Hospital Episode Statistics Admitted Patient Care of England, and Civil Registration Mortality databases and Danish Shoulder Arthroplasty Registry and National Patient Register were used for our modelling study. Patients aged 18-100 years who had a primary shoulder replacement between April 1, 2012, and Oct 2, 2020, in England, and April 1, 2012, and Oct 2, 2018, in Denmark, were included. We developed a multivariable logistic regression model using the English dataset to predict the risk of 90-day serious adverse events, which were defined as medical complications requiring admission to hospital and all-cause death. We undertook internal validation using bootstrapping, and internal-external cross-validation across different geographical regions of England. The English model was externally validated on the Danish dataset.

FINDINGS

Data for 40 631 patients undergoing primary shoulder replacement (mean age 72·5 years [SD 9·9]; 28 709 [70·7%] women and 11 922 [29·3%] men) were used for model development, of whom 2270 (5·6%) had a 90-day serious adverse event. On internal validation, the model had a C-statistic of 0·717 (95% CI 0·707-0·728) and was well calibrated. Internal-external cross-validation showed consistent model performance across all regions in England. Upon external validation on the Danish dataset (n=6653; mean age 70·5 years [SD 10·3]; 4503 [67·7%] women and 2150 [32·3%] men), the model had a C-statistic of 0·750 (95% CI 0·723-0·776). Decision curve analysis showed clinical utility, with net benefit across all risk thresholds.

INTERPRETATION

This externally validated prediction model uses commonly available clinical variables to accurately predict the risk of serious medical complications after primary shoulder replacement surgery. The model is generalisable and applicable to most patients in need of a shoulder replacement. Its use offers support to clinicians and could inform and empower patients in the shared decision-making process.

FUNDING

National Institute for Health and Care Research and the Department of Orthopaedic Surgery, Herlev and Gentofte Hospital, Denmark.

Predictors of inpatient mortality following reverse shoulder arthroplasty

INTRODUCTION

The number of reverse shoulder arthroplasties (RSA) performed each year is growing rapidly, especially in elderly patients and with expanded indications including geriatric proximal humerus fractures. As the elderly population grows and the number of RSA's annually continues to rise, there will be a proportionate number of adverse events and mortality. However, the rate of early mortality has consistently shown to be less than 1%, so a large-scale analysis of possible risk factors for post-operative mortality is warranted.

METHODS

A retrospective multivariate analysis of 59,915 patients from the National Inpatient Sample database between 2016 and 2019 was performed. Patients who underwent RSA were identified based on ICD-10 code. Patients were divided into two groups, early mortality and no mortality. Early mortality was defined as those who died within the same admission. Patient demographics and medical comorbidities were evaluated. Hospital admission status was classified as elective or non-elective. Odds ratios for predictive variables were measured as a ratio of incidence between the early mortality and no mortality groups.

RESULTS

The overall incidence of inpatient mortality was 0.07%. The incidence of mortality for elective admissions was 0.04% and for non-elective admissions was 0.34%. On univariate analysis, age greater than 75 years (p < 0.001), octogenarians (p < 0.001), nonagenarians (p < 0.001), and non-elective admission (p < 0.001) were associated with early mortality following RSA. Upon multivariate analysis, age greater than 75 years old had 4 times the odds of early mortality following RSA (OR 4.20; 95%CI (1.67, 10.60); p < 0.001) while non-elective admission had about 5 times the odds (OR 5.38; 95%CI (2.75, 10.53); p < 0.001).

DISCUSSION

Age greater than 75 years old has 4-fold higher odds and non-elective admission has 5-fold higher odds of early mortality following RSA. Appropriate pre-operative counseling should be performed with elderly patients and those undergoing non-elective indications for RSA.

Two-year follow-up of the SMR stemless platform shoulder system: a multicenter, prospective clinical study

Background

The use of stemless shoulder arthroplasty for osteoarthritis has grown substantially over the past decades. The goal of this study is to evaluate the clinical and radiological outcomes of the Lima SMR stemless anatomic and reverse total shoulder arthroplasty.

Methods

Seventy-three implants in 73 patients (61 anatomic total shoulder arthroplasties [aTSAs] and 12 reverse shoulder arthroplasties [RSAs]) were analyzed with a minimum follow-up of 2 years. The average age in the aTSA group was 65.8 ± 8.7 and 78.3 ± 4.8 in the RSA group. Primary osteoarthritis was the indication in most cases (aTSA 93.7%, RSA 67%). Patients were evaluated preoperatively, at 4, 12, and 24 months postoperatively using the Constant score, the ASES, Oxford Shoulder Score, EuroQol 5 Dimensions 5 Levels questionnaire, range of motion scores, and radiographically. Statistical significance was evaluated using the paired t-test (P < .5).

Results

At 2-year follow-up, the overall average Constant score significantly improved from 40.0 ± 16.7 to 80.9 ± 21.4 (P < .001). Improvement of the ASES (from 31.7 ± 15.6 to 82.5 ± 19.4) and Oxford Shoulder Score (from 19.1 ± 7.4 to 41.9 ± 7.9) was also significant (P < .001). In the aTSA group, all range of motion scores improved significantly (P < .001). In the RSA group, all range of motion scores improved but only active forward flexion and external rotation in abduction improved significantly (P < .05). Most patients were satisfied or completely satisfied at 24 months (aTSA 93.9%, RSA 100%). Two humeral implants in the RSA configuration showed loosening on the first postoperative day related to excessive forces exerted on the shoulder, both requiring revision to a stemmed implant. In the aTSA group, no signs of radiolucencies, osteolysis, gradual loosening, or migration of the components were seen at the final follow-up. In the RSA group, one case had radiolucent lines with subsidence of the humeral core at 12 months, which had not progressed at 24 months and was asymptomatic. All other RSA cases showed no radiolucent lines, migration, scapular notching, or osteolysis. Three anatomic implants were converted with retention of the glenoid baseplate and humeral core to a reverse arthroplasty due to atraumatic cuff failure (N = 2) and traumatic cuff failure (N = 1). After these procedures, patients were satisfied with their results. There were no other complications.

Conclusion

The 2-year results presented in this study show good functional and radiological outcomes using the SMR stemless system.

Radiologic, clinical, and patient-reported outcomes in stemless reverse shoulder arthroplasty at a mean of 46 months

BACKGROUND

The humeral stem can be a cause of problems in shoulder arthroplasty, for example, loss of bone stock, intraoperative and postoperative periprosthetic fractures, or postoperative infections involving the medullary canal. Therefore, stemless reverse shoulder arthroplasty (slRSA) has gained popularity, particularly in terms of preserving bone stock. However, there are limited data available on the midterm outcomes of slRSA. The objective of this study was to evaluate the clinical, radiologic, and patient-reported outcomes of slRSA at a minimum follow-up period of 2 years.

METHODS

Data on all stemless reverse shoulder prostheses implanted between January 2016 and October 2020 were collected. Patients were followed up at 6 weeks and 6, 12, and 24 months postoperatively. Clinical and radiologic data as well as patient-reported outcome measures were assessed with validated questionnaires (University of California at Los Angeles Shoulder Score [UCLA], American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form [ASES], Quick Disabilities of the Arm, Shoulder, and Hand questionnaire [Quick-DASH], visual analog scale [VAS] for pain, Subjective Shoulder Value [SSV], and Constant-Murley score [CS]). All patients had a minimum follow-up of 2 years.

RESULTS

During the observation period, 26 shoulders in 25 patients fulfilled the inclusion criteria. The mean follow-up was 46.8 months (range 25-66). The mean age was 70.1 years (range 59.9-86.4). At the most recent follow-up, a significant improvement was noted in the ASES score (55.9 ± 19.9 vs. 85.6 ± 10.7, P < .001), SSV (44.3 ± 18.7 vs. 85.3 ± 10.4, P < .001), Quick-DASH score (40.6 ± 22.0 vs. 17.8 ± 13.9, P < .001), VAS pain score (4.6 ± 3.2 vs. 0.9 ± 1.2, P < .001), and range of motion in flexion (66 ± 53 vs. 154 ± 22, P < .001) as well as in the absolute (44.1 ± 18.7 vs. 83.1 ± 10.1, P < .001) and relative CS (62.1 ± 27.8 vs. 111.9 ± 13.3, P < .001). Scapular notching was observed in 16% of cases, and radiolucent lines were detected in 28% of cases without symptoms of implant loosening. No revision was necessitated by any causes related to the stemless humeral component. Hence, implant survivorship was 100%.

CONCLUSIONS

With an ASES score showing a 30-point improvement and thus exceeding the minimal clinically important difference of 21 points and no revisions due to the stemless component, these results indicate that slRSA is a viable option, providing good to excellent midterm outcomes that are comparable to those of stemmed reverse shoulder prostheses, with the added advantage of bone stock preservation.

Machine learning can predict anterior elevation after reverse total shoulder arthroplasty: A new tool for daily outpatient clinic?

The aim of the present study was to individuate and compare specific machine learning algorithms that could predict postoperative anterior elevation score after reverse shoulder arthroplasty surgery at different time points. Data from 105 patients who underwent reverse shoulder arthroplasty at the same institute have been collected with the purpose of generating algorithms which could predict the target. Twenty-eight features were extracted and applied to two different machine learning techniques: Linear regression and support vector regression (SVR). These two techniques were also compared in order to define to most faithfully predictive. Using the extracted features, the SVR algorithm resulted in a mean absolute error (MAE) of 11.6° and a classification accuracy (PCC) of 0.88 on the test-set. Linear regression, instead, resulted in a MAE of 13.0° and a PCC of 0.85 on the test-set. Our machine learning study demonstrates that machine learning could provide high predictive algorithms for anterior elevation after reverse shoulder arthroplasty. The differential analysis between the utilized techniques showed higher accuracy in prediction for the support vector regression. Level of Evidence III: Retrospective cohort comparison; Computer Modeling.

Five-Year Mortality Rates Following Elective Shoulder Arthroplasty and Shoulder Arthroplasty for Fracture in Patients Over Age 65

Background

To effectively counsel patients prior to shoulder arthroplasty, surgeons should understand the overall life trajectory and life expectancy of patients in the context of the patient's shoulder pathology and medical comorbidities. Such an understanding can influence both operative and nonoperative decision-making and implant choices. This study evaluated 5-year mortality following shoulder arthroplasty in patients ≥65 years old and identified associated risk factors.

Methods

We utilized Centers for Medicare & Medicaid Services Fee-for-Service inpatient and outpatient claims data to investigate the 5-year mortality rate following shoulder arthroplasty procedures performed from 2014 to 2016. The impact of patient demographics, including fracture diagnosis, year fixed effects, and state fixed effects; patient comorbidities; and hospital-level characteristics on 5-year mortality rates were assessed with use of a Cox proportional hazards regression model. A p value of <0.05 was considered significant.

Results

A total of 108,667 shoulder arthroplasty cases (96,104 nonfracture and 12,563 fracture) were examined. The cohort was 62.7% female and 5.8% non-White and had a mean age at surgery of 74.3 years. The mean 5-year mortality rate was 16.6% across all shoulder arthroplasty cases, 14.9% for nonfracture cases, and 29.9% for fracture cases. The trend toward higher mortality in the fracture group compared with the nonfracture group was sustained throughout the 5-year postoperative period, with a fracture diagnosis being associated with a hazard ratio of 1.63 for mortality (p < 0.001). Medical comorbidities were associated with an increased risk of mortality, with liver disease bearing the highest hazard ratio (3.07; p < 0.001), followed by chronic kidney disease (2.59; p < 0.001), chronic obstructive pulmonary disease (1.92; p < 0.001), and congestive heart failure (1.90; p < 0.001).

Conclusions

The mean 5-year mortality following shoulder arthroplasty was 16.6%. Patients with a fracture diagnosis had a significantly higher 5-year mortality risk (29.9%) than those with a nonfracture diagnosis (14.9%). Medical comorbidities had the greatest impact on mortality risk, with chronic liver and kidney disease being the most noteworthy. This novel longer-term data can help with patient education and risk stratification prior to undergoing shoulder replacement.

Level of Evidence

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

The Obesity Paradox: A Nonlinear Relationship Between 30-Day Postoperative Complications and Body Mass Index After Total Shoulder Arthroplasty

BACKGROUND

An inverse relationship coined the "obesity paradox" has been propositioned, in which body mass index (BMI) may be contradictorily protective in patients undergoing surgery or treatment of chronic disease. This study sought to investigate the BMI associated with the lowest rate of medical complications after total shoulder arthroplasty (TSA).

METHODS

The American College of Surgeons National Surgical Quality Improvement Project database was queried to identify adults who underwent elective primary TSA between January 2012 and December 2020. Thirty-day postoperative medical complications were extracted, which included death, readmission, pneumonia, pulmonary embolism, renal failure, and cardiac arrest, among others. BMI was classified into five categories (underweight [BMI <18.5 kg/m 2 ], normal weight [BMI ≥18.5 and <25 kg/m 2 ], overweight [BMI ≥25 and <30 kg/m 2 ], obese [BMI ≥30 and <40 kg/m 2 ], and morbidly obese [BMI ≥40 kg/m 2 ]). We examined the risk of any 30-day postoperative complications and BMI categorically and on a continuous basis using multivariable logistic regression controlling for age, sex, procedure year, and comorbidities.

RESULTS

Of the 31,755 TSAs, 84% were White, 56% were female, and the average age of patients was 69.2 ± 9.3 years. Thirty-day postoperative medical complications occurred in 4.53% (n = 1,440). When assessed on a continuous basis, the lowest risk was in patients with a BMI between 30 and 35 kg/m 2 . Underweight individuals (BMI <18.5 kg/m 2 ) had the highest postoperative complication rates overall. The probability of medical complications increased with age and was greater for female patients.

CONCLUSION

The relationship between BMI and complication risk in TSA is nonlinear. A BMI between 30 and 35 kg/m 2 was associated with the lowest risk of medical complications after TSA, and BMI<18.5 kg/m 2 had the highest risk overall, indicating some protective aspects of BMI against 30-day medical complications. Thus, obesity alone should not preclude patients from TSA eligibility, rather surgical candidacy should be evaluated in the context of patients' overall health and likelihood of benefit from TSA.

LEVEL OF EVIDENCE

III, Retrospective Comparative Study.

Understanding Medical Optimization for Patients Undergoing Shoulder Arthroplasty

Many surgeons seek to optimize their patients' comorbid conditions preoperatively to reduce postoperative complications. To effectively optimize patients before total shoulder arthroplasty, the surgeon should be familiar with recognizing and treating common medical comorbidities found in an orthopedic patient including anemia, diabetes, malnutrition, cardiovascular conditions, and history of deep venous thrombosis. Screening for depression or other mental illness should also be conducted preoperatively and managed accordingly before surgery. Preoperative opioid use and smoking have significant effects on postoperative outcomes and should be addressed before surgery.

Shoulder Arthroplasty as a Day Case: Is It Better?

Introduction: A retrospective case-controlled study was performed to evaluate the outcomes of shoulder arthroplasty performed as a day case in carefully selected patients, compared to the traditional inpatient approach. Materials and Methods: Patients who had total or hemiarthroplasty of the shoulder performed as a day case or inpatient procedure were recruited. The primary outcome compared rates of uneventful recovery, defined by the absence of complications or readmission to the hospital within six months of surgery, between the inpatient and outpatient groups. Secondary outcomes included examiner-determined functional and patient-determined pain scores at one, six, twelve, and twenty-four weeks post-surgery. A further assessment of patient-determined pain scores was carried out at least two years post-surgery (5.8 ± 3.2). Results: 73 patients (36 inpatients and 37 outpatients) were included in the study. Within this time frame, 25/36 inpatients (69%) had uneventful recoveries compared to 24/37 outpatients (65%) (p = 0.17). Outpatients showed significant improvement over pre-operative baseline levels in more secondary outcomes (strength and passive range-of-motion) by six months post-operation. Outpatients also performed significantly better than inpatients in external rotation (p < 0.05) and internal rotation (p = 0.05) at six weeks post-surgery. Both groups showed significant improvement compared to pre-operative baselines in all patient-determined secondary outcomes except the activity level at work and sports. Inpatients, however, experienced less severe pain at rest at six weeks (p = 0.03), significantly less frequent pain at night (p = 0.03), and extreme pain (p = 0.04) at 24 weeks, and less severe pain at night at 24 weeks (p < 0.01). By a minimum of two years post-operation, inpatients were more comfortable repeating their treatment setting for future arthroplasty (16/18) compared to outpatients (7/22) (p = 0.0002). Conclusions: At a minimum of two years of follow-up, there were no significant differences in rates of complications, hospitalizations, or revision surgeries between patients that underwent shoulder arthroplasty as an inpatient versus an outpatient. Outpatients demonstrated superior functional outcomes but reported more pain at six months post-surgery. Patients in both groups preferred inpatient treatment for any future shoulder arthroplasty. What is Known About This Subject: Shoulder arthroplasty is a complex procedure and has traditionally been performed on an inpatient basis, with patients admitted for six to seven days post-surgery. One of the primary reasons for this is the high level of post-operative pain, usually treated with hospital-based opioid therapy. Two studies demonstrated outpatient TSA to have a similar rate of complications as inpatient TSA; however, these studies only examined patients within a shorter-term 90-day post-operative period and did not evaluate functional outcomes between the two groups or in the longer term. What This Study Adds to Existing Knowledge: This study provides evidence supporting the longer-term results of shoulder arthroplasty done as a day case in carefully selected patients, which are comparable to outcomes in patients that are admitted to the hospital post-surgery.

Economic and educational disparities are associated with an increased risk of revision surgery following shoulder arthroplasty

BACKGROUND

There is limited literature exploring how nonmedical factors such as social determinants of health (SDOHs) are associated with postoperative outcomes following shoulder arthroplasty.

METHODS

A retrospective cohort review of the Pearl Diver Database was used to capture patients undergoing either primary anatomic total or reverse shoulder arthroplasty from the fourth quarter of 2015 to the third quarter of 2019 with at least 1 year of active longitudinal follow-up. Patients with proximal humeral fractures, stress fractures, or septic arthritis were excluded. The included patients were then divided into 2 cohorts based on the presence of current SDOHs or a history of SDOHs. The SDOH cohort comprised 4 non-mutually exclusive categories: economic, educational, social, and environmental disparities. Subsequently, a control cohort was matched at a 1:1 ratio to the SDOH cohort. Primary outcome measures were assessed using a logistic regression and consisted of the following 90-day postoperative complications: minor and major medical complications and infection. Emergency department (ED) visits and readmissions for any cause were also assessed. Additionally, the following 1-year outcomes were assessed: aseptic loosening, instability, and revision arthroplasty. Surgical costs and 90-day postoperative costs were collected using averaged insurance reimbursements for both the control and SDOH cohorts.

RESULTS

There were 5190 patients in each cohort. Economic disparities made up the largest portion of the SDOH cohort (n = 4631, 89.2%), followed by social (n = 741, 14.3%), environmental (n = 417, 8.0%), and educational (n = 99, 1.9%) disparities. Compared with the control cohort, SDOHs were associated with an increased risk of major complications (2.3% vs. 1.4%; odds ratio [OR], 1.55; 95% confidence interval [CI], 1.29-1.87; P < .001), minor complications (5.7% vs. 3.8%; OR, 1.62; 95% CI, 1.21-1.95; P = .001), readmissions (4.3% vs. 2.8%; OR, 1.56; 95% CI, 1.26-1.84; P < .001), and ED visits (15.2% vs. 11.0%; OR, 1.45; 95% CI, 1.29-1.63; P < .001) within 90 days following surgery. Additionally, SDOHs were associated with an increased risk of aseptic loosening (1.1% vs. 0.6%; OR, 1.85; 95% CI, 1.20-2.65; P = .006), instability (4.0% vs. 2.2%; OR, 1.80; 95% CI, 1.43-2.28; P < .001), and ipsilateral revision (9.2% vs. 7.6%; OR, 1.24; 95% CI, 1.08-1.43; P < .001) at 1 year postoperatively compared with the control cohort.

CONCLUSION

SDOHs are associated with increased rates of adverse outcomes following shoulder arthroplasty including revision surgery, ED visits, length of stay, and overall cost compared with matched controls without SDOHs. Specifically, economic and educational disparities are associated with increased rates of adverse outcomes following surgery including revision surgery, ED visits, length of stay, and overall cost.

Encouraging outcomes of stemless ceramic head anatomic shoulder arthroplasty in severe primary osteoarthritis (Walch type B glenoids)

Background: We report the radiological and functional outcomes at five years in patients with severe osteoarthritis of the glenohumeral joint and a Walch type B glenoid who have undergone stemless anatomic total shoulder replacement. Methods: A retrospective analysis of case notes, computed tomography scans and plain radiographs of patients undergoing anatomic total shoulder replacement for primary glenohumeral osteoarthritis were performed. Patients were grouped by the severity of their osteoarthritis using the modified Walch classification, glenoid retroversion and posterior humeral head subluxation. An evaluation was made using modern planning software. Functional outcomes were assessed using the American shoulder and elbow surgeons score, shoulder pain and disability index and visual analogue scale. Annual Lazarus scores were reviewed as regard to glenoid loosening. Results: Thirty patients were reviewed at 5 years. Analysis of all patient-reported outcome measures demonstrated significant improvement at 5-year review, American shoulder and elbow surgeons (p = <0.0001), shoulder pain and disability index (p = 0.0001), visual analogue scale (p = 0.0001). Radiological associations between Walch scores and Lazarus scores were not statistically significant (p = 0.1251) at 5 years. There were no associations between features of glenohumeral osteoarthritis and patient-reported outcome measures. Discussion: The severity of osteoarthritis did not show any association with glenoid component survivorship or with patient-reported outcome measures at 5 years review. Level of evidence: IV.

Short-term results of a new anatomic stemless shoulder arthroplasty - A prospective multicentre study

Background

Anatomic total shoulder arthroplasty (TSA) has been continuously developed and current designs include stemless or canal-sparing humeral components. In the literature stemless and canal sparing TSA showed good clinical and radiographic results, which were comparable to stemmed TSA.

Objective

The aim of this study was to determine the short-term clinical and radiological outcomes of a new stemless TSA design.

Methods

A prospective multicentre study including 154 total shoulder arthroplasty patients with a follow up of 12 months was performed. At the time of follow up 129 patients were available for review. The adjusted Constant Murley score,¹ Oxford Shoulder Score, EQ-5D-5L score and radiographs were examined preoperatively, 3 and 12 months after the implantation of the new stemless TSA implant GLOBAL ICON™ (DePuy Synthes, Warsaw, IN, USA). Complications were documented.

Results

Implant Kaplan-Meier survivorship was 98.7% at 12 months. From baseline to 12 months follow-up, all scores showed a progressive significant mean improvement. The mean adjusted Constant score increased from 42.3 to 96.1 points (p<0.001). The Oxford Shoulder Score showed an increase of 21.6 points (p<0.001). The postoperative radiographs showed no continuous radiolucent lines, subsidence, aseptic loosening or progressive radiolucency, but one osteolytic lesion was observed. Only 2 prostheses were revised.

Conclusion

The new GLOBAL ICON stemless TSA showed good clinical and radiographic results at short-term follow up which were comparable to early results of other stemless TSA. Further studies with longer follow up are needed in the future.

Few UK vascular centres offer a fully NICE-compliant supervised exercise programme: a national audit

INTRODUCTION

To determine the current (pre-COVID-19) provision of supervised exercise training (SET) for patients with peripheral arterial disease (PAD) in UK Vascular Centres.

METHODS

Hospital Trusts delivering vascular care to patients with PAD were identified from the National Vascular Registry and asked to complete an online questionnaire on their provisions for SET. If a centre offered SET, they were asked questions to determine whether the programme was compliant with NICE guidelines and the difficulties they faced delivering the service. If centres did not offer SET, they were asked what obstacles prevented them implement SET.

RESULTS

Of the 78 UK vascular centres, 59 (76%) responded and were included in the audit. Of these, 27 (46%) were able to offer SET but only 21 (36%) could offer it to all their patients with PAD. Only four (6.8%) offered SET that was fully compliant with current NICE guidelines. Reasons identified included insufficient funding, lack of resource and poor patient compliance.

CONCLUSIONS

The benefits of SET are well established yet the availability of the service in the UK is poor. The reasons for this are readily identified but have not yet been overcome. Research on novel methods of delivering supervised exercise that mitigates existing barriers, such as home exercise with remote monitoring, should be prioritised to facilitate optimal management for our patients with PAD.

Comorbidity scores reported in anatomic and reverse total shoulder arthroplasty: a systematic review

BACKGROUND

Due to the aging population, the number of reverse shoulder arthroplasty (RSA) and anatomic shoulder arthroplasty (TSA) continue to increase annually. Although outcome measures are frequently reported in literature for patients who undergo shoulder arthroplasty, no studies have analyzed reporting of patient comorbidities in this population. The purpose of this study was to evaluate reporting of comorbidity indices in shoulder arthroplasty literature and assess how this reporting may inform management and outcomes.

METHODS

A database was compiled systematically using PubMed to identify articles pertaining to shoulder arthroplasty published between 2019 and 2021. The search terms, "reverse shoulder arthroplasty" and "anatomic shoulder arthroplasty," were used to identify clinical studies. Non-clinical (e.g., translational and basic science) and review articles were excluded. Included studies were then analyzed for reporting of comorbidity indices.

RESULTS

A total of 199 articles were included in this review and reported comorbidities. Of these, 15.6% (31 of 199) pertained to TSA, while 84.4% (168 of 199) pertained to RSA. Within this review, 57.8% (115 of 199) articles utilized comorbidity scores, while 42.2% (84 of 199) reported only comorbid diagnoses. Among the scores utilized, the American Society of Anesthesiologists (ASA) physical status classification system was the most widely used among both the TSA (52.9%, 9 of 17) and the RSA studies (58.2%, 57 of 98). Additional scores within the RSA literature included the Charlson Comorbidity Index (CCI) (35.3%, 6 of 17), the Charlson Comorbidity Index by Deyo et al. (J Clin Epidemiol. 45(6):613-9, 1992) (CCI-Deyo; 5.9%, 1 of 17), the Modified Charlson Comorbidity Index (modified-CCI) (5.9%, 1 of 17), the Elixhauser et al. (Med Care. 36(1):8-27, 1998) Comorbidity Measure (ECM) (11.8%, 2 of 17), and the Modified Frailty Index (mFI) (5.9%, 1 of 17). With the TSA literature, the additional comorbidity scores included the CCI (30.6%, 30 of 98), the CCI-Deyo (6.1%, 6 of 98), the modified-CCI (1.0%, 1 of 98), the ECM (8.2%, 8 of 98), the Factor-5 modified Frailty Index (mFI-5) (1.0%, 1 of 98), and the mFI (1.0%, 1 of 98).

CONCLUSION

The reporting of comorbidity indices is an important factor when considering patient outcomes and complications reported in shoulder arthroplasty literature. Although the reporting of these scores appears to be more prevalent in current literature, there is no standard or consistency in terms of which scores are reported. Given this diversity in comorbidity scores, further research is necessary to develop a single standardized score to properly analyze the effect of comorbidities on shoulder arthroplasty patient outcomes.

Stemless reverse total shoulder arthroplasty: a systematic review

BACKGROUND

The use of reverse total shoulder arthroplasty and stemless anatomic total shoulder replacement has been increasing in the United States every year. Stemless humeral components in reverse total shoulder arthroplasty are only approved for clinical trials in the United States with an investigational device exception with limited data.

METHODS

A systematic review on stemless reverse total shoulder arthroplasty was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A search was conducted on November 25, 2020, using the MEDLINE/PubMed, Cochrane, and Embase databases. All articles were reviewed by 2 independent evaluators, with any conflicts or issues resolved by consensus or a final decision by the senior author. The primary outcomes extracted were complications, radiographic results, and outcome scores.

RESULTS

We evaluated 10 studies that used either the Total Evolutive Shoulder System (TESS) or Verso implant. There were 430 total patients and 437 total procedures; 266 patients in the TESS group underwent a total of 272 procedures, and 164 patients in the Verso group underwent a total of 165 procedures. The mean age at the time of surgery was 73.8 years (range, 38-93 years). The mean follow-up period ranged from 6.4 to 101.6 months per study. There was an overall trend of improved clinical outcome scores, a 0.2% humeral component loosening rate, and an 11.2% complication rate.

CONCLUSIONS

This review shows that the clinical and functional outcomes following stemless or metaphyseal reverse total shoulder arthroplasty are quite promising, especially with the low rate of humeral-sided complications. There continues to be a need for additional long-term studies and randomized clinical trials.

Apoptotic cells derived micro/nano-sized extracellular vesicles in tissue regeneration

Extracellular vesicles (EVs), products released by cells in multiple biological activities, are currently widely accepted as functional particles and intercellular communicators. From the orthodox perspective, EVs derived from apoptotic cells (apoEVs) are responsible for cell debris clearance, while recent studies have demonstrated that apoEVs participate in tissue regeneration. However, the underlying mechanisms and particular functions in tissue regeneration promotion of apoEVs remain ambiguous. Some molecules, such as caspases, active during apoptosis also function in tissue regeneration triggered by apoptosis,. ApoEVs are generated in the process of apoptosis, carrying cell contents to manifest biological effects, and possessing biomarkers to target phagocytes. The regenerative effect of apoEVs might be due to their abilities to facilitate cell proliferation and regulate inflammation. Such regenerative effect has been observed in various tissues, including skin, bone, cardiovascular system, and kidney. Engineered apoEVs are produced to amplify the biological benefits of apoEVs, rendering them optional for drug delivery. Meanwhile, challenges exist in thorough mechanistic exploration and standardization of production. In this review, we discussed the link between apoptosis and regeneration, current comprehension of the origination and investigation strategies of apoEVs, and mechanisms in tissue regeneration by apoEVs and their applications. Challenges and prospects are also discussed here.

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.

In-hospital Complications Are More Likely to Occur After Reverse Shoulder Arthroplasty Than After Locked Plating for Proximal Humeral Fractures

BACKGROUND

Currently, there seems to be a paradigm change in the surgical treatment of proximal humeral fractures in patients aged 65 years and older, with a considerable increase in the use of reverse total shoulder arthroplasty (RTSA) compared with angular stable internal fixation (locking plate fixation). However, even among shoulder specialists there is controversy regarding the best treatment strategy.

QUESTIONS/PURPOSES

To evaluate for (1) a greater risk of in-hospital major adverse events, (2) a greater risk for in-hospital surgical complications, and (3) a greater risk of 30-day mortality, locking plate fixation and RTSA were compared for the treatment of proximal humerus fractures of patients aged 65 years and older after controlling for potentially confounding variables in a large-database analysis.

METHODS

Health claims data of the largest German insurance company including approximately one-third of the population (26.5 million policyholders) between 2010 and 2018 were analyzed. This database was chosen because of its size, nationwide distribution, and high quality/completeness. In total, 55,070 patients (≥ 65 years of age) treated with locking plate fixation (75% [41,216]) or RTSA (25% [13,854]) for proximal humeral fracture were compared. As primary endpoints, major adverse events (including acute myocardial infarction, stroke, organ failure, resuscitation, and death) and surgical complications (infection, hematoma, loss of reduction, dislocation, and revision surgery) were analyzed. The risk of all endpoints was analyzed with multivariable logistic regression models in the context of comorbidities to address existing group differences.

RESULTS

After controlling for potentially confounding variables such as age, sex, and risk profile, RTSA was associated with a higher risk for major adverse events (OR 1.40 [95% CI 1.29 to 1.53]; p < 0.001) and surgical complications (OR 1.13 [95% CI 1.05 to 1.21]; p < 0.01) compared with locking plate fixation. There was no evidence for an increase in mortality (OR 0.98 [95% CI 0.86 to 1.12]; p = 0.81).

CONCLUSION

The increased in-hospital risk for major adverse events and surgical complications may moderate the enthusiasm associated with RTSA for proximal humeral fractures in patients 65 years and older. Treatment decisions should be based on individual risk estimation to avoid potential harmful events. Future studies must include long-term outcomes and quality of life to enlighten these findings in a broader context.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Venous thromboembolism complications in shoulder surgery: current concepts

Venous thromboembolism (VTE) is a rare yet known complication of shoulder surgery. Concerning shoulder arthroplasty, reported rates of VTE range from 0.2% to 16%. Unlike many lower extremity procedures, particularly total hip and knee arthroplasty, chemical prophylactic guidelines for VTE in shoulder surgeries have not been established. Some argue that doing so is unnecessary. On the contrary, mechanical prophylaxis is nearly universally accepted in shoulder surgery, particularly for more lengthy procedures. With limited VTE incidence in shoulder surgery, treatment is anecdotally derived from the hip and knee arthroplasty literature. Recent studies have successfully identified risk factors for VTE related to the patient and to the surgery itself. Awareness of these risk factors by the surgeon and declaration of these factors to the patient should be discussed as part of the informed consent process. Further investigational studies and larger patient cohorts will be necessary to optimise VTE prevention in shoulder surgeries.

The Feasibility of Outpatient Shoulder Arthroplasty: Risk Stratification and Predictive Probability Modeling

Whether shoulder arthroplasty can be performed on an outpatient basis depends on appropriate patient selection. The purpose of this study was to identify risk factors for adverse events (AEs) following shoulder arthroplasty and to generate predictive models to improve patient selection. This was a retrospective review of prospectively collected data using a single institution shoulder arthroplasty registry as well as the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database, including subjects undergoing hemiarthroplasty, total shoulder arthroplasty (TSA), and reverse TSA. Predicted probability of suitability for same-day discharge was calculated from multivariable logistic models for different patient subgroups based on age, comorbidities, and Charlson/Deyo Index scores. A total of 2314 shoulders (2079 subjects) in the institutional registry met inclusion criteria for this study. Younger age, higher body mass index (BMI), male sex, and prior steroid injection were all significantly associated with suitability for discharge, whereas preoperative narcotic use, comorbidities (heart disease and anemia/other blood disease), and Charlson/Deyo Index score of 2 were associated with AEs that might prevent same-day discharge. Compared with TSA, reverse TSA was associated with less suitability for discharge (P=.01). On querying the ACS-NSQIP database, 15,254 patients were identified. Female sex, BMI less than 35 kg/m², American Society of Anesthesiologists class III/IV, preoperative anemia, functional dependence, low pre-operative albumin, and hemiarthroplasty were associated with unsuitability for discharge. Males 55 to 59 years old with no comorbidities nor history of narcotic use formed the lowest risk subgroup. Transfusion is the primary driver of AEs. Strategies to avoid this complication should be explored. Risk stratification will improve the ability to identify patients who can safely undergo outpatient shoulder arthroplasty. [Orthopedics. 2021;44(2):e215-e222.].

Low-dose aspirin and the rate of symptomatic venous thromboembolic complications following primary shoulder arthroplasty

BACKGROUND

Venous thromboembolism (VTE) events are infrequent but potentially catastrophic complications following orthopedic surgery. There is currently a paucity of evidence regarding the role of chemoprophylaxis with low-dose aspirin (acetylsalicylic acid [ASA]) after shoulder arthroplasty.

METHODS

We conducted a retrospective review of prospectively collected complications occurring within 90 days of 2394 primary shoulder arthroplasties performed over a 3-year period at a single institution. Patients preoperatively underwent risk stratification into medically high risk, moderate risk, or low risk as part of a standardized navigated-care pathway. For chemoprophylaxis, 81 mg of ASA (low dose) was routinely used once daily for 6 weeks unless alternative medications were deemed necessary by the medical team. Baseline demographic information, medical comorbidities, and postoperative VTE prophylaxis, as well as rates of clinically symptomatic VTE, were assessed.

RESULTS

Symptomatic VTE occurred after 0.63% of primary shoulder arthroplasties (15 of 2394). There were 9 patients with deep vein thromboses and 6 with pulmonary embolisms. Eighty-one milligrams of ASA was used in 2141 patients (89.4%), resulting in an overall VTE rate of 0.56%. Medically high-risk patients were significantly more likely to have a VTE (P = .018). Patients with a history of deep vein thrombosis, asthma, and cardiac arrhythmia were significantly more likely to have a VTE (P < .05). Complications occurred in 4 patients (0.19%) associated with low-dose ASA and 1 patient (0.63%) associated with a novel oral anticoagulant medication.

CONCLUSION

Routine use of low-dose ASA results in a very low risk of VTE and medication-associated complications following primary shoulder arthroplasty. Preoperative medical risk stratification can potentially identify patients at high risk of postoperative VTE.

Complication rates and outcomes after outpatient shoulder arthroplasty: a systematic review

Background

As the number of total shoulder arthroplasties (TSAs) performed annually increases, some surgeons have begun to shift toward performing TSAs in the outpatient setting. However, it is imperative to establish the safety of outpatient TSA. The purpose of this systematic review was to define complication, readmission, and reoperation rates and patient-reported outcomes after outpatient TSA.

Methods

A systematic review of the literature was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using three databases (PubMed, Ovid, and Embase). English-language publications describing results on complication rates in patients who underwent TSA in an outpatient or ambulatory setting were included. All nonclinical and deidentified database studies were excluded. Bias assessment was conducted with the methodologic index for nonrandomized studies criteria.

Results

Seven studies describing outcomes in outpatient TSA were identified for inclusion. The included studies used varying criteria for selecting patients for an outpatient procedure. The total outpatient 90-day complication rate (commonly including hematomas, wound issues, and nerve palsies) ranged from 7.1%-11.5%. Readmission rates ranged from 0%-3.7%, and emergency and urgent care visits ranged from 2.4%-16.1%. Patient-reported outcomes improved significantly after outpatient TSA in all studies. Two studies found a higher complication rate in the comparative inpatient cohort (P = .023-.027). Methodologic index for nonrandomized studies scores ranged from 9 to 11 (of 16) for noncomparative studies (n = 3), while all comparative studies received a score of a 16 (of 24).

Conclusion

Outpatient TSA in properly selected patients results in a similar complication rate to inpatient TSA. Further studies are needed to aid in determining proper risk stratification to direct patients to inpatient or outpatient shoulder arthroplasty.

Is venous thromboembolism prophylaxis beneficial in upper limb major joint replacement surgery? A systematic review

BACKGROUND

Upper limb arthroplasty is an increasingly used treatment modality for end-stage joint disease of the shoulder, elbow and wrist. Whilst complications have been reported, the risk of venous thromboembolism has received less attention when compared to the lower limb. Guidance to aid clinical decision-making remains limited. This review aims to ascertain whether venous thromboembolism prophylaxis is beneficial after upper limb major joint replacement surgery.

METHODS

A systematic review was performed in April 2019, utilising EMBASE, MEDLINE, Cochrane and Google Scholar. All clinical studies reporting venous thromboembolism incidence and risk reduction (after prophylaxis) in upper limb joint replacement were included.

RESULTS

Twenty-four observational studies were identified. The reported incidence of venous thromboembolism ranged from 0.2% to 16% (weighted mean 0.68%) and 0.2% to 0.8% (weighted mean 0.49%) in shoulder and elbow arthroplasty, respectively. No records for wrist arthroplasty were found. In the literature, baseline venous thromboembolism risk of patients without an operation is reported as 0.5%.

DISCUSSION

There is a lack of good quality evidence regarding the risks and benefits of venous thromboembolism prophylaxis in upper limb major joint replacement surgery. We recommend further research, ideally formal randomised controlled trials to guide recommendations. Although venous thromboembolism is rare in upper limb surgery, surgeons should remain vigilant to this possibility.

Rate of venous thromboembolism after surgical treatment of proximal humerus fractures

INTRODUCTION

The rate of venous thromboembolism following surgical treatment of proximal humerus fractures is not well established.

METHODS

A retrospective review of all patients undergoing surgical treatment for proximal humerus fractures from September 2011 to May 2017 was performed. Included patients received only mechanoprophylaxis using sequential compression devises. All patients had at least 6 months follow-up. The primary outcome of interest was the rate of postoperative DVT and PE.

RESULTS

131 patients underwent 139 surgeries for proximal humerus fracture. After exclusion criteria were applied, 92 patients who underwent 92 surgeries were included. There were 47 females and 45 males. Five (5.4%) were taking Aspirin 81 mg preoperatively. There were 76 cases of open reduction and internal fixation (ORIF), 8 cases of reverse total shoulder arthroplasty, 4 cases of hemiarthroplasty, 3 cases of closed reduction percutaneous pinning (CRPP), 1 case of open reduction without fixation. 53.3% of patients had one or more risk factors for VTE. There were no cases of fatal PE or DVT. There were two cases of symptomatic PE (2.2%) following one ORIF and one CRPP. There was one additional case of asymptomatic PE found incidentally after ORIF. Overall VTE rate was 3.3%. Fisher's exact test yielded that there was no significant association between the presence of VTE risk factors and prevalence of VTE postoperatively (p = 0.245).

CONCLUSIONS

The incidence of symptomatic VTE after surgery for proximal humerus fractures is low. Chemical VTE prophylaxis in patients after surgical fixation for proximal humerus fractures is not universally indicated. Selective prophylaxis for patients with systemic risk factors may be warranted.

Are Arthroplasty Procedures Really Better in the Treatment of Complex Proximal Humerus Fractures? A Comprehensive Meta-Analysis and Systematic Review

OBJECTIVE

A meta-analysis and systematic review was performed to compare outcomes of open reduction and internal fixation (ORIF), hemiarthroplasty (HA), and reverse total shoulder arthroplasty (rTSA) for complex proximal humerus fractures. Data sources: MEDLINE, Embase, and Cochrane Library databases were screened. Search terms included reverse total shoulder arthroplasty, open reduction internal fixation, hemiarthroplasty, and proximal humerus fracture.

STUDY SELECTION

English-language studies published within the past 15 years evaluating outcomes of ORIF, rTSA, or HA for complex proximal humerus fractures with minimum of 1-year follow-up were included, resulting in 51 studies with 3064 total patients. Review articles, basic science studies, biomechanical studies, and cadaveric studies were excluded.

DATA EXTRACTION

The methodological quality of evidence was assessed using the Jadad scale and methodological index for nonrandomized studies.

DATA SYNTHESIS

Demographic data were compared using the χ2 test. Mean data were weighted by study size and used to calculate composite mean values and confidence intervals. Continuous data were compared using the Metan module with fixed effects. Count data were compared using the Kruskal-Wallis test. Alpha was set at 0.05 for all tests.

CONCLUSIONS

Patients undergoing rTSA had lower risks of complication (relative risk 0.41) and reoperation (relative risk 0.28) than HA patients. rTSA resulted in higher Constant scores (standard mean difference 0.63) and improved active forward flexion when compared with HA (standard mean difference 0.76). Pooled mean data demonstrated better outcome scores and active forward flexion of ORIF versus HA and rTSA, although the patients were younger and had more simple fracture patterns.

LEVEL OF EVIDENCE

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

The Impact of Preoperative Anemia on Complications After Total Shoulder Arthroplasty

This study investigated the relationship between varying levels of preoperative anemia and postoperative complications within 30 days of total shoulder arthroplasty (TSA).

What Is the Accuracy of Three Different Machine Learning Techniques to Predict Clinical Outcomes After Shoulder Arthroplasty?

BACKGROUND

Machine learning techniques can identify complex relationships in large healthcare datasets and build prediction models that better inform physicians in ways that can assist in patient treatment decision-making. In the domain of shoulder arthroplasty, machine learning appears to have the potential to anticipate patients' results after surgery, but this has not been well explored.

QUESTIONS/PURPOSES

(1) What is the accuracy of machine learning to predict the American Shoulder and Elbow Surgery (ASES), University of California Los Angeles (UCLA), Constant, global shoulder function, and VAS pain scores, as well as active abduction, forward flexion, and external rotation at 1 year, 2 to 3 years, 3 to 5 years, and more than 5 years after anatomic total shoulder arthroplasty (aTSA) or reverse total shoulder arthroplasty (rTSA)? (2) What is the accuracy of machine learning to identify whether a patient will achieve clinical improvement that exceeds the minimum clinically important difference (MCID) threshold for each outcome measure? (3) What is the accuracy of machine learning to identify whether a patient will achieve clinical improvement that exceeds the substantial clinical benefit threshold for each outcome measure?

METHODS

A machine learning analysis was conducted on a database of 7811 patients undergoing shoulder arthroplasty of one prosthesis design to create predictive models for multiple clinical outcome measures. Excluding patients with revisions, fracture indications, and hemiarthroplasty resulted in 6210 eligible primary aTSA and rTSA patients, of whom 4782 patients with 11,198 postoperative follow-up visits had sufficient preoperative, intraoperative, and postoperative data to train and test the predictive models. Preoperative clinical data from 1895 primary aTSA patients and 2887 primary rTSA patients were analyzed using three commercially available supervised machine learning techniques: linear regression, XGBoost, and Wide and Deep, to train and test predictive models for the ASES, UCLA, Constant, global shoulder function, and VAS pain scores, as well as active abduction, forward flexion, and external rotation. Our primary study goal was to quantify the accuracy of three machine learning techniques to predict each outcome measure at multiple postoperative timepoints after aTSA and rTSA using the mean absolute error between the actual and predicted values. Our secondary study goals were to identify whether a patient would experience clinical improvement greater than the MCID and substantial clinical benefit anchor-based thresholds of patient satisfaction for each outcome measure as quantified by the model classification parameters of precision, recall, accuracy, and area under the receiver operating curve.

RESULTS

Each machine learning technique demonstrated similar accuracy to predict each outcome measure at each postoperative point for both aTSA and rTSA, though small differences in prediction accuracy were observed between techniques. Across all postsurgical timepoints, the Wide and Deep technique was associated with the smallest mean absolute error and predicted the postoperative ASES score to ± 10.1 to 11.3 points, the UCLA score to ± 2.5 to 3.4, the Constant score to ± 7.3 to 7.9, the global shoulder function score to ± 1.0 to 1.4, the VAS pain score to ± 1.2 to 1.4, active abduction to ± 18 to 21°, forward elevation to ± 15 to 17°, and external rotation to ± 10 to 12°. These models also accurately identified the patients who did and did not achieve clinical improvement that exceeded the MCID (93% to 99% accuracy for patient-reported outcome measures (PROMs) and 85% to 94% for pain, function, and ROM measures) and substantial clinical benefit (82% to 93% accuracy for PROMs and 78% to 90% for pain, function, and ROM measures) thresholds.

CONCLUSIONS

Machine learning techniques can use preoperative data to accurately predict clinical outcomes at multiple postoperative points after shoulder arthroplasty and accurately risk-stratify patients by preoperatively identifying who may and who may not achieve MCID and substantial clinical benefit improvement thresholds for each outcome measure.

CLINICAL RELEVANCE

Three different commercially available machine learning techniques were used to train and test models that predicted clinical outcomes after aTSA and rTSA; this device-type comparison was performed to demonstrate how predictive modeling techniques can be used in the near future to help answer unsolved clinical questions and augment decision-making to improve outcomes after shoulder arthroplasty.

Predicting Postoperative Course After Total Shoulder Arthroplasty Using a Medical-Social Evaluation Model

INTRODUCTION

The ability to predict successful outcomes is important for patient satisfaction and optimal results after shoulder arthroplasty. We hypothesize that a medical-social scoring tool will predict resource requirements in doing total shoulder arthroplasty (TSA).

METHODS

A retrospective analysis of 453 patients undergoing TSA was undertaken. Preoperatively, medical and social surveys were completed by each patient. Demographics, comorbidity scores, hospital course, postdischarge disposition, and readmissions were collected.

RESULTS

The average length of stay was 1.6 days (0 to 7). There was an association with utilization of home care or inpatient rehabilitation and both the medical (7.3 versus 3.9; P = 0.0002) and social (7.1 versus 3.4; P < 0.0001) components of the survey. There was a weak correlation between hospital length of stay and the social component of the survey (R = 0.29; P < 0.001), but not the medical component (R = 0.04; P = 0.38). No variable was predictive of readmission. Social score of eight was found to be predictive of postoperative requirement of home care or rehabilitation.

CONCLUSION

This study found that Medical and Social Survey Scores can stratify patients who are at risk of requiring more advanced postdischarge care and/or a longer hospital stay. With this, we can match patients to the most appropriate level of postoperative care.

Screw fixation in stemless shoulder arthroplasty for the treatment of primary osteoarthritis leads to less osteolysis when compared to impaction fixation

Background

Stemless total shoulder arthroplasty is a well-established and reliable surgical treatment option for glenohumeral osteoarthritis resulting in loss of pain and improvement of shoulder function. Currently the two methods for the fixation of the humeral component are either screw fixation or impaction. The purpose of this study is the clinical and radiological comparison of two different stemless designs (screw fixation vs impaction) for total shoulder arthroplasties in patients suffering from primary glenohumeral osteoarthritis.

Methods

A retrospective cohort study including 39 patients with a mean age of 67 years and a minimum follow-up of 2 years was performed. Patients were separated into two groups based on the selected implant. In group A (n = 18) a screw fixation design and in group B (n = 21) an impaction type design was used. For clinical examination the Constant-Murley-Score (CS) and Subjective-Shoulder-Value (SSV) were evaluated. Radiological examination was performed on true-AP, axial and Y-view radiographs.

Results

In group A the CS increased from 27.1 to 65.2 points and SSV from 27.3 to 76.7% (p > 0.05). No osteolysis of the medial calcar or subsidence of the humeral implant were found in this group. In group B the CS increased from 29.0 to 72.6 points and SSV from 33.1 to 85% (p < 0.05). Osteolysis of the medial calcar was present in seven patients in this group. No signs for humeral loosening were found in both groups.

Conclusion

Impaction and screw fixation total shoulder arthroplasty for primary glenohumeral osteoarthritis using a stemless device provide reliable clinical results. The screw fixation seems to prevent osteolysis of the medial calcar.

Predictors of mortality following shoulder arthroplasty

Introduction

This study aims to determine 30-day, 90-day and 1 year mortality following shoulder arthroplasty and identify predictors of mortality.

Materials and methods

All shoulder arthroplasty cases performed at the host institution, between 2012 and 2018 were included. A review of patient records was completed to identify demographic data, Charlson comorbidity index, date of death and factors associated with mortality.Mortality analysis was undertaken using 1-Kaplan Meier estimates with 95% confidence intervals. Comparative analysis was performed for mortality following shoulder arthroplasty for elective vs. trauma and for primary vs. revision surgery. A multiple regression analysis was conducted to determine which factors were associated with increased mortality risk.

Results

640 shoulder arthroplasty cases were performed in 566 patients. There were 44 deaths, 1 occurred within 90 days and 13 within 1 year. Trauma procedures had a hazard ratio of 5.3 (95% CI 1.9 to 15.0) for mortality compared to elective procedures (5 year survival trauma 78.6% (95% CI 60.7 to 89.0); elective 91.8% (95% CI 88.1 to 94.4). 1-year mortality was predicted by presence of malignancy, liver failure, cardiac failure, peptic ulcer, trauma surgery, revision surgery, intra-operative complication, transfusion and increased length of stay.

Discussion

30-day, 90-day and 1-year mortality following shoulder arthroplasty were 0%, 0.16% and 2%; trauma procedures had a hazard ratio of 5.3 for 1-year mortality when compared to elective surgery. Malignancy, cardiac failure, liver failure, peptic ulcer and trauma surgery are associated with an increased risk of 1-year mortality.

Is surgical duration associated with postoperative complications in primary shoulder arthroplasty?

BACKGROUND

Surgical duration is an independent predictor of short-term adverse outcomes after a variety of orthopedic procedures, both arthroscopic and open. However, this association in shoulder arthroplasty remains unclear. The purpose of this study was to identify the association between surgical duration and postoperative complications, as well as increased use of health care resources, after shoulder arthroplasty.

METHODS

Primary shoulder arthroplasty procedures performed from 2005 to 2016 were identified in the American College of Surgeons National Surgical Quality Improvement Program database using Current Procedural Terminology codes. Surgical duration was divided into 3 cohorts: (1) surgical procedures lasting less than 90 minutes, (2) those lasting between 90 and 120 minutes, and (3) those lasting more than 120 minutes. Baseline patient characteristics and outcome variables were compared using bivariate analysis. Outcome variables were compared using multivariate analysis.

RESULTS

Overall, 14,106 patients were identified. Longer surgical duration was significantly associated with younger age, male patients, higher body mass index, and use of general anesthesia, (P < .001 for each), as well as smoking history (P < .39). Relative to operative times shorter than 90 minutes, surgical procedures lasting more than 120 minutes had higher rates of any complication (P = .002), return to the operating room (P = .008), urinary tract infection (P = .02), non-home discharge (P < .001), blood transfusion (P < .001), and unplanned 30-day hospital readmission (P = .03).

CONCLUSION

Increasing surgical duration was associated with a variety of postoperative medical complications and increased use of health care resources including discharge to acute care facilities, blood transfusions, and hospital readmission. These data suggest that surgical duration should be considered for postoperative risk stratification, as well as patient counseling, and may be a surgeon-modifiable risk factor independent of patient risk factors.

Ambulatory versus inpatient shoulder arthroplasty: a population-based analysis of trends, outcomes, and charges

Background

The purpose of this study was to evaluate the clinical outcomes and cost of shoulder arthroplasty (SA) performed in ambulatory surgery centers (ASCs) compared with SA performed in hospital-based surgery settings.

Methods

The State Inpatient Databases and the State Ambulatory Surgery Databases were queried for patients undergoing primary or reverse SA between 2010 and 2014 in 5 states in either the inpatient (IP), hospital outpatient department (HOPD), or ASC setting. Outcomes included all-cause readmissions, emergency department visits within the 90-day postoperative period, and charges. Covariates included patient demographic data and procedure details. Risk factors for readmission were calculated using logistic regression analysis.

Results

We identified 795 ASC (2%), 183 HOPD (0.5%), 38,114 (97.5%) SA procedures. The outpatient cohort was overall younger and healthier with a lower percentage of diabetes (14.1% vs. 20.2%), cardiopulmonary disease (11.4% vs. 20.4%), and obesity (10.7% vs. 15.6%). The US state and obesity were factors significantly (P < .0001) associated with readmission. The median IP charge was $62,905 (range, $41,327-$87,881) vs. $37,395 (range, $21,976-$61,775) for combined outpatient cases. When outpatient SA was stratified into ASC and HOPD cases, the median charges were $31,790 for ASC cases vs. $55,990 for HOPD cases (P < .0001). After adjustment for multiple covariates, the charges for combined outpatient SA surgery were 40% lower than those for IP SA surgery (P < .0001).

Conclusion

As the current health care climate shifts toward lower-cost and higher-quality care, this study demonstrates that SAs performed in ASCs have a comparable safety profile to and significant financial advantage over SAs performed in the hospital-based setting.

High Tibial Osteotomy Survivorship: A Population-Based Study

Background

High tibial osteotomy (HTO) was developed to treat early medial compartment osteoarthritis in varus knees.

Purpose

To evaluate the midterm and long-term outcomes of HTO in a large population-based cohort of patients.

Study Design

Case-control study; Level of evidence, 3.

Methods

Data from the California Office of Statewide Health Planning and Development were used to identify patients undergoing HTO from 2000 to 2014. Patients with infectious arthritis, rheumatological disease, congenital deformities, malignancy, concurrent arthroplasty, or skeletal trauma were excluded. Demographic information was assessed for every patient. Failure was defined as conversion to total or unicompartmental knee arthroplasty. Differences between patients requiring arthroplasty and those who did not were identified using univariate analysis. Multivariate analysis was performed, and Kaplan-Meier survivorship estimates for 5- and 10-year survival were computed.

Results

A total of 1576 procedures were identified between 2000 and 2014; of these, 358 procedures were converted to arthroplasty within 10 years. Patients who went on to arthroplasty after HTO were older (48.23 ± 6.76 vs 42.66 ± 9.80 years, respectively; P < .001), had a higher incidence of hypertension (25.42% vs 17.82%, respectively; P = .001), and had a higher likelihood of having ≥1 comorbidity (38.0% vs 31.4%, respectively; P = .044). Patients were 8% more likely to require arthroplasty for each additional year in age (relative risk [RR], 1.08). Female patients were also at an increased risk of conversion to arthroplasty compared with male patients (RR, 1.38). Survivorship at 5 and 10 years was 80% and 56%, respectively, and the median time to failure was 5.1 years.

Conclusion

HTO may provide long-term survival in select patients. Careful consideration should be given to patient age, sex, and osteoarthritis of the knee when selecting patients for this procedure.

The short- to midterm effectiveness of stemless prostheses compared to stemmed prostheses for patients who underwent total shoulder arthroplasty: a meta-analysis

BACKGROUND

To systematically compare the short- to midterm effectiveness of stemless prostheses to that of stemmed prostheses for patients who underwent total shoulder arthroplasty (TSA) and to provide a guideline for clinical decision-making.

METHODS

PubMed, the Cochrane Library, and Web of Science were searched with the given search terms until July 2019 to identify published articles evaluating the clinical outcomes for stemless prostheses compared with stemmed prostheses for patients who underwent TSA. Data extraction and the quality assessment of the included studies were independently performed by two authors. Stata software 14.0 was used to analyze and synthesize the data.

RESULTS

Two randomized controlled trials and six case-controlled studies with a total of 347 shoulders were included in this meta-analysis. The results of this meta-analysis showed that there were no significant differences between the stemless and stemmed prostheses in terms of the Constant score, pain score, strength, activities of daily living, postoperative range of motion (ROM), and postoperative maximum active ROM.

CONCLUSIONS

This is the first meta-analysis reporting the clinical results of stemless TSA in the short- to midterm follow-up period. Both types of shoulder prostheses were similar in achieving satisfactory clinical outcomes.

Core set of unfavorable events of shoulder arthroplasty: an international Delphi consensus process

BACKGROUND

Shoulder arthroplasty (SA) complications require standardization of definitions and are not limited to events leading to revision operations. We aimed to define an international consensus core set of clinically relevant unfavorable events of SA to be documented in clinical routine practice and studies.

METHODS

A Delphi exercise was implemented with an international panel of experienced shoulder surgeons selected by nomination through professional societies. On the basis of a systematic review of terms and definitions and previous experience in establishing an arthroscopic rotator cuff repair core set, an organized list of SA events was developed and reviewed by panel members. After each survey, all comments and suggestions were considered to revise the proposed core set including local event groups, along with definitions, specifications, and timing of occurrence. Consensus was reached with at least two-thirds agreement.

RESULTS

Two online surveys were required to reach consensus within a panel involving 96 surgeons. Between 88% and 100% agreement was achieved separately for local event groups including 3 intraoperative (device, osteochondral, and soft tissue) and 9 postoperative event groups. Experts agreed on a documentation period that ranged from 3 to 24 months after SA for 4 event groups (peripheral neurologic, vascular, surgical-site infection, and superficial soft tissue) and that was lifelong until implant revision for other groups (device, osteochondral, shoulder instability, pain, late hematogenous infection, and deep soft tissue).

CONCLUSION

A structured core set of local unfavorable events of SA was developed by international consensus to support the standardization of SA safety reporting. Clinical application and scientific evaluation are needed.

Risk of poor outcomes in patients who are obese following total shoulder arthroplasty and reverse total shoulder arthroplasty: a systematic review and meta-analysis

BACKGROUND

A systematic review was performed to investigate the impact of obesity on outcomes following total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RTSA).

METHODS

Electronic databases and the grey literature were searched for studies that evaluated the influence of obesity (body mass index ≥ 30 kg/m²) on TSA and RTSA outcomes. A total of 15 studies were identified, with 10 studies reporting on predetermined outcomes considered in the TSA and RTSA population. Unadjusted data were pooled in a statistical meta-analysis where appropriate (Review Manager [RevMan], version 5.3) or summarized in narrative form. Effect sizes were expressed as odds ratios (ORs) for categorical data and weighted mean differences (WMDs) for continuous data.

RESULTS

The findings suggested that patients who were obese were at increased odds of a dislocation (OR, 2.49; 95% confidence interval [CI], 2.32-2.66), fracture (OR, 1.92; 95% CI, 1.77-2.08), and revision (OR, 1.49; 95% CI, 1.40-1.58) following TSA or RTSA. Conversely, obesity had no influence on the odds of an unscheduled return to the operating theater (OR, 0.83; 95% CI, 0.43-1.61). Postoperative forward flexion in patients who were obese differed from that in patients who were not obese (WMD, -9.8°; 95% CI, -17.53° to -2.07°); however, no differences in other functional measures including abduction (WMD, -0.78; 95% CI, -7.27 to 5.71) and external rotation (WMD, -1.41; 95% CI, -5.11 to 2.29) were found. Although patients who were obese reported significantly higher levels of pain (WMD, 1.13; 95% CI, 0.21 to 2.06), the difference was not clinically relevant.

CONCLUSIONS

Surgeons should consider advising patients who are obese of the greater risk of dislocation, fracture, and revision when considering elective TSA or RTSA. Findings are limited by confounding variables but further our understanding of additional risks associated with pre-existing obesity, which will promote better-informed decisions prior to proceeding with surgery.

A Point-Based Model to Predict Absolute Risk of Revision in Anatomic Shoulder Arthroplasty

Background

Total shoulder arthroplasty (TSA) has demonstrated good long-term survivorship but early implant failure can occur. This study identified factors associated with shoulder arthroplasty revision and constructed a risk score for revision surgery following shoulder arthroplasty.

Methods

A validated algorithm was used to identify all patients who underwent anatomic TSA between 2002 and 2012 using population-based data. Demographic variables included shoulder implant type, age and sex, Charlson comorbidity score, income quintile, diagnosis, and surgeon arthroplasty volume. The associations of covariates with time to revision were measured while treating death as a competing risk and were expressed in the Shoulder Arthroplasty Revision Risk Score (SARRS).

Results

During the study period, 4079 patients underwent TSA. Revision risk decreased in a nonlinear fashion as patients aged and in the absence of osteoarthritis with no influence from surgery type or other covariables. The SARRS ranged from −21 points (5-year revision risk 0.75%) to 30 points (risk 11.4%). Score discrimination was relatively weak 0.55 (95% confidence interval: 0.530.61) but calibration was very good with a test statistic of 5.77 (df = 8, P = .762).

Discussion

The SARRS model accurately predicted the 5-year revision risk in patients undergoing TSA. Validation studies are required before this score can be used clinically to predict revision risk. Further study is needed to determine if the addition of detailed clinical data including functional outcome measures and the severity of glenohumeral arthrosis increases the model’s discrimination.

Modified frailty index predicts medical complications, length of stay, readmission, and mortality following total shoulder arthroplasty

HYPOTHESIS

The purpose of this study was to evaluate the 5-factor modified frailty index (mFI-5) as a predictor of postoperative complications in patients undergoing total shoulder arthroplasty (TSA).

METHODS

We conducted a retrospective analysis of the National Surgical Quality Improvement Program database for patients undergoing TSA between the years 2005 and 2017. The mFI-5 score, which includes the presence of comorbid diabetes, hypertension, congestive heart failure, chronic obstructive pulmonary disease, and functional status, was calculated for each patient. Multivariate logistic regression models were used to assess the relationship between the mFI-5 and postoperative complications.

RESULTS

A total of 18,957 patients undergoing TSA were identified. The mFI-5 was a strong predictor of serious medical complications (cardiac arrest, myocardial infarction, septic shock, pulmonary embolism, postoperative dialysis, reintubation, and prolonged ventilator requirement), discharge to a facility, and readmission (odds ratio ≥ 1.309, P ≤ .001). Length of stay also increased as the mFI-5 score increased (P < .001). However, among all the measured complications, the mFI-5 was the strongest predictor of mortality, with the risk more than doubling for each point increase in the mFI-5 score (odds ratio, 2.113; 95% confidence interval, 1.447-3.086; P < .001).

CONCLUSION

The mFI-5 predicts serious medical complications, increased length of stay, discharge to a facility, hospital readmission, and mortality in patients undergoing TSA. All of the variables within the mFI-5 are easily obtained through the patient history, allowing for a practical clinical tool that hospitals and surgeons can use to identify high-risk surgical candidates, inform preoperative counseling, and guide perioperative care to optimize patient outcomes.

Complications after surgical treatment of proximal humerus fractures in the elderly-an analysis of complication patterns and risk factors for reverse shoulder arthroplasty and angular-stable plating

BACKGROUND

To date, there is a lack of consensus regarding surgical treatment recommendations for complex proximal humerus fracture (PHF) patterns, especially between joint preservation and joint replacement techniques.

METHODS

Between 2012 and 2017, 146 patients (aged 74.1 ± 8.0 years) with complex PHF were treated with locking plates (open reduction-internal fixation [ORIF]) or reverse total shoulder arthroplasty (RTSA). Complications and unplanned revision surgery were recorded in a mid-term follow-up. Potential patient and surgical risk factors for complications were extracted. Univariate and multivariate analyses were conducted.

RESULTS

Follow-up data were available for 125 patients, 66 (52.8%) of whom were treated with locking plates, and 59 (41.2%) with RTSA. Both groups had comparable Charlson indices. The overall complication rate was 37.8% for ORIF and 22.0% for RTSA, with a revision rate of 12.1% and 5.1%, respectively, as driven primarily by persistent motion deficits. Multivariate analyses demonstrated no significant differences between the 2 procedures (P = .500). However, age was an independent protective factor against overall complications (P = .018). Risk factors for major complications in ORIF included osteoporosis, varus impaction fractures, posteromedial metaphyseal extensions <8 mm, head-shaft displacements >4 mm, and multifragmentary greater tuberosities. For RTSA, higher complication rates were seen in patients with higher Charlson indices, diabetes, or altered (greater) tuberosities. In contrast, Neer's classification system was not predictive in either group.

CONCLUSIONS

RTSA led to fewer complications than ORIF and thus can be considered a valuable option in complex PHF of the elderly. Paying attention to specific prognostic factors may help to reduce the complication rate.

Does proximal porous coating in short-stem humeral arthroplasty reduce stress shielding?

CONTEXT

Short-stem humeral designs in shoulder arthroplasty have been introduced recently. A retrospective cohort study was conducted to determine if newer proximal porous titanium coating in humeral short stems produced clinical and radiologic improvements.

METHOD

Short-stem humeral implants (Tornier Ascend, Wright Medical) were used in 46 anatomical total shoulder replacements from October 2012 to December 2015. Clinical and radiologic measures were analyzed at one- and two-year follow-up.

RESULTS

Nineteen shoulders received earlier grit blasted stems (Ascend Monolithic), and 27 shoulders received the later stems with proximal titanium porous coating (Ascend Flex). At two-year follow-up, radiographic changes and stress shielding were similar. Medial cortical thinning were more frequently observed in Monolithic (18 of 19) compared to Flex stems (19 of 27) on the PA films, though this was not statistically significant (P = 0.061). Clinical outcome scores improved regardless of the stem type used and independent of the radiologic adaptations on plain films. One participant with the Ascend Flex developed glenoid component failure and rotator cuff tear and was subsequently revised.

DISCUSSION

Clinical and radiological outcomes are similar in both short-stem designs. Proximal titanium porous coating may reduce medial calcar cortical thinning but it does not prevent it.

KEY MESSAGE

When compared to similarly designed uncoated grit-blasted stems, proximally porous coated humeral short stems produced similar clinical and radiological results. The proximal titanium porous coating may reduce medial cortical thinning.

Preoperative indications for total shoulder arthroplasty predict adverse postoperative complications

BACKGROUND

Although studies have shown improved pain, function, and patient satisfaction after total shoulder arthroplasty (TSA), preoperative factors predicting poor outcomes are unexplored. Comparison of postoperative complications between osteoarthritis (OA), cuff arthropathy (CA), and fracture patients is important for identifying at-risk patients.

METHODS

Primary TSAs from 2014 to 2016 with preoperative OA, CA, and proximal humerus fractures as indications were queried from the National Surgical Quality Improvement Program database. Short-interval postoperative complications were compared using multivariate binary logistic regression, and postoperative time to discharge between groups was analyzed using univariate analysis of variance with Tukey comparison. Statistical significance was defined as P < .05 using SPSS software version 23.0 (IBM Corp., Armonk, NY, USA).

RESULTS

Of 9684 TSA cases, the primary indication was OA in 6571 patients, CA in 725 patients, and fractures in 646 patients. Compared with fractures, OA patients had statistically significant lower risk of dislocation, readmission, return to operating room, nonhome discharge, surgical site infection, perioperative bleeding requiring transfusion, and pulmonary embolism (all P < .05). Statistically significant lower risk of dislocation, nonhome discharge, and transfusion was also found between CA and fracture patients (all P < .03). However, in comparing CA vs. OA as preoperative indications, only postoperative venous thromboembolism (odds ratio, 4.5; P = .01) and surgical site infection (odds ratio, 3.7; P = .007) were significant. Mean differences in discharge time were significant between both OA and CA groups compared with fractures (P < .001), but there was no significance between OA and CA (P = .116).

CONCLUSION

Proximal humerus fracture is a risk factor for increased postoperative complications compared with OA and CA. With new outcomes-based reimbursement models, nonroutine discharge and increased discharge time should be considered in arthroplasty planning.

Low revision rate despite poor functional outcome after stemmed hemiarthroplasty for acute proximal humeral fractures: 2,750 cases reported to the Danish Shoulder Arthroplasty Registry

Background and purpose - The revision rate of stemmed hemiarthroplasty (SHA) for acute proximal humeral fractures is low, but does not necessarily reflect the functional outcome. We report the revision rate of SHA for acute proximal humeral fractures and the proportion of arthroplasties that are not revised despite low functional outcome scores. Patients and methods - The Danish Shoulder Arthroplasty Registry was used to identify all patients with a proximal humeral fracture that was treated with a SHA between January 1, 2006 and December 31, 2015. Information on demographics, surgical procedures, and revisions was collected by the registry. The Western Ontario Osteoarthritis of the Shoulder (WOOS) index at 1 year was used as functional outcome score. We converted the score to a percentage of a maximum score with 100 being the best. Results - 2,750 SHAs in 2,719 patients were included. Mean age was 72 years (SD 11); 79% were women. Mean WOOS at 1 year was 55 (SD 26). A total of 101 (4%) arthroplasties were revised, and the 10-year cumulative implant survival rate was 95%. The Cox regression model showed a statistically significant impact on implant survival of age, but not of sex or arthroplasty brand. A WOOS score below 30 and 50 was reported in 11% and 25% of patients, respectively. Interpretation - We found a high implant survival rate, but also a high proportion of patients with a low functional outcome score 1 year after surgery.

Demographics and Risk Factors for Non-Accidental Orthopedic Trauma

Childhood non-accidental trauma (NAT) is the second most common cause of death in children. Despite its prevalence, NAT is frequently unreported due to provider misdiagnosis or unawareness. The purpose of this study was to determine current risk factors and injury patterns associated with NAT. A retrospective review of the Kids' Inpatient Database was performed for the years 2009 and 2012. Univariate and multivariate analyses were used to determine the statistically significant risk factors for NAT. In 2009 and 2012, 174 442 children were hospitalized for fractures. Of these, 2.07% (3614) were due to NAT. Lower extremity (femur, tibia/fibula, foot), hand/carpus, clavicle, pelvis, and spine fractures were more likely to result from NAT; tibia/fibula fractures were most predictive of NAT. Children with anxiety, attention-deficit, conduct, developmental, and mood disorders were more likely to experience NAT. Those with cerebral palsy and autism were not at an increased risk for NAT.

Results of total shoulder arthroplasty in patients aged 55 years or younger versus those older than 55 years: an analysis of 1135 patients with over 2 years of follow-up

BACKGROUND

The results of anatomic total shoulder arthroplasty (TSA) in younger patients have not been clearly elucidated. The purpose of this study was to compare early outcomes after TSA in patients aged 55 years or younger versus patients older than 55 years.

METHODS

A total of 1135 patients who were treated with TSA for glenohumeral arthritis and had a mean follow-up period of over 4 years were retrospectively reviewed. Etiologies included osteoarthritis (n = 1044), osteonecrosis (n = 35), inflammatory arthritis (n = 34), and post-traumatic arthritis (n = 22). Validated outcome measures, range of motion, and patient satisfaction were recorded. Preoperative and postoperative metrics were compared, and a multivariate analysis was performed to isolate age from sex, body mass index, previous surgery, and diagnosis as independent factors.

RESULTS

Female patients, patients with a history of surgery, and patients with a diagnosis of osteonecrosis were more likely to undergo TSA when aged 55 years or younger. Both age groups showed similar preoperative range of motion and showed no differences in recorded outcome scores. Postoperatively, patients older than 55 years had slightly greater active abduction (P = .004) and internal rotation (P = .030). A higher percentage of patients older than 55 years rated their outcome as better or much better compared with those aged 55 years or younger (P = .003).

CONCLUSIONS

Female sex, a history of surgery, and a diagnosis of osteonecrosis were associated with undergoing TSA when aged 55 years or younger. Despite similar preoperative function and minor differences in postoperative range of motion and outcome scores, patients aged 55 years or younger reported lower overall satisfaction with their TSA.

Risk Factors for Mortality and Readmission After Shoulder Hemiarthroplasty for Fracture

BACKGROUND

Limited information exists regarding mortality and readmission following proximal humerus fracture. This study examines risk factors following hemiarthroplasty for these fractures.

METHODS

A retrospective analysis of prospectively collected data on 788 patients treated with hemiarthroplasty for acute proximal humerus fracture from January 2005 to December 2011 was conducted. One-year mortality and 30- and 90-day hospital readmission were evaluated. Patient risk factors included age, race, gender, diabetes, American Society of Anesthesiologists (ASA) score, and body mass index.

RESULTS

One-year mortality rate was 5.2%. Patients with ASA ≥3 had 2.37 times (95% confidence interval [CI]: 1.05-5.32) greater mortality risk versus patients with ASA1/2. The 30-day readmission rate was 8.4% and at 90 days was 12.6%. Females had 0.53 risk of readmission versus males (95% CI: 0.29-0.96). Patients with ASA ≥3 had 1.79 (95% CI: 1.04-3.09) risk of 90-day readmission versus patients with ASA1/2; females had 0.52 (95% CI: 0.31-0.85) risk of readmission versus males. Increased age increased all odds ratios.

CONCLUSIONS

Readmission rate after hemiarthroplasty for proximal humerus fracture is significant both at 30 and 90 days and is higher in males. Age and ASA ≥3 correlate with this. Diabetes and obesity were not significant risk factors for readmission or mortality.

Venous Thromboembolism After Shoulder Arthoplasty and Arthroscopy

Venous thromboembolism (VTE) in the orthopaedic literature largely focuses on lower extremity trauma and arthroplasty, with relatively few investigations of VTE after shoulder surgery. Because the rate of shoulder surgery, especially arthroplasty, continues to expand, it is important for practicing surgeons to understand the magnitude of risk, potential consequences, and prevention methods with regard to VTE. VTE after shoulder surgery has been a topic of increasing interest over the past decade, and the purpose of this review is to examine the recent literature on pathophysiology, risk factors, incidence, diagnosis, sequelae, prevention, treatment, and current recommendations regarding VTE after shoulder surgery.

What Associations Exist Between Comorbidity Indices and Postoperative Adverse Events After Total Shoulder Arthroplasty?

BACKGROUND

Comorbidity indices like the modified Charlson Comorbidity Index (mCCI) and the modified Frailty Index (mFI) are commonly reported in large database outcomes research. It is unclear if they provide greater association and discriminative ability for postoperative adverse events after total shoulder arthroplasty (TSA) than simple variables.

QUESTIONS/PURPOSES

Using a large research database to examine postoperative adverse events after anatomic and reverse TSA, we asked: (1) Which demographic/anthropometric variable among age, sex, and body mass index (BMI) has the best discriminative ability as measured by receiver operating characteristics (ROC)? (2) Which comorbidity index, among the American Society of Anesthesiologists (ASA) classification, the mCCI, or the mFI, has the best ROC? (3) Does a combination of a demographic/anthropometric variable and a comorbidity index provide better ROC than either variable alone?

METHODS

Patients who underwent TSA from 2005 to 2015 were identified from the National Surgical Quality Improvement Program (NSQIP). This multicenter database with representative samples from more than 600 hospitals in the United States was chosen for its prospectively collected data and documented superiority over administrative databases. Of an initial 10,597 cases identified, 70 were excluded due to missing age, sex, height, weight, or being younger than 18 years of age, leaving a total of 10,527 patients in the study. Demographics, medical comorbidities, and ASA scores were collected, while BMI, mCCI and mFI were calculated for each patient. Though all required data variables were found in the NSQIP, the completeness of data elements was not determined in this study, and missing data were treated as being the null condition. Thirty-day outcomes included postoperative severe adverse events, any adverse events, extended length of stay (LOS, defined as > 3 days), and discharge to a higher level of care. ROC analysis was performed for each variable and outcome, by plotting its sensitivity against one minus the specificity. The area under the curve (AUC) was used as a measure of model discriminative ability, ranging from 0 to 1, where 1 represents a perfectly accurate test, and 0.5 indicates a test that is no better than chance.

RESULTS

Among demographic/anthropometric variables, age had a higher AUC (0.587-0.727) than sex (0.520-0.628) and BMI (0.492-0.546) for all study outcomes (all p < 0.050), while ASA (0.580-0.630) and mFI (0.568-0.622) had higher AUCs than mCCI (0.532-0.570) among comorbidity indices (all p < 0.050). A combination of age and ASA had higher AUCs (0.608-0.752) than age or ASA alone for any adverse event, extended LOS, and discharge to higher level of care (all p < 0.05). Notably, for nearly all variables and outcomes, the AUCs showed fair or moderate discriminative ability at best.

CONCLUSION

Despite the use of existing comorbidity indices adapted to large databases such as the NSQIP, they provide no greater association with adverse events after TSA than simple variables such as age and ASA status, which have only fair associations themselves. Based on database-specific coding patterns, the development of database- or NSQIP-specific indices may improve their ability to provide preoperative risk stratification.

LEVEL OF EVIDENCE

Level III, diagnostic study.