Shoulder Arthroplasty in the Upper Extremity Weight-bearing Patient: A Systematic Review of Clinical Outcomes and Complications.

BACKGROUND: Patients who rely on their upper extremities for ambulation, or upper extremity ambulators (UEAs), place considerable stress on their shoulders through the use of assistive devices like walkers, crutches, canes, and wheelchairs. It has been postulated that UEAs may be at increased risk for complications following shoulder arthroplasty. This study aimed to systematically review the literature related to (1) patient-reported outcomes measures (PROMs), (2) functional outcomes, and (3) complications in UEAs who undergo shoulder arthroplasty. METHODS: A systematic review of the PubMed/MEDLINE, Embase, and Cochrane databases was performed to identify studies reporting clinical outcomes of shoulder arthroplasty in UEAs. Patient demographics, clinical characteristics, PROMs, radiographic outcomes, and postoperative range of motion were collected and compared to control patients (i.e. bipedal ambulators) from the constituent studies. RESULTS: A total of eight studies evaluating 248 UEA cases and 206 control cases were included for review. Ambulatory assistive devices utilized by UEAs included walkers (39%), wheelchairs (38%), canes (22%), and a crutch (<1%). Among UEA cases, 197 (79%) reverse total shoulder arthroplasty, 37 (15%) anatomic total shoulder arthroplasty, and 14 (6%) hemiarthroplasty were performed. Overall, patients exhibited significant improvements in mean American Shoulder and Elbow Surgeons (ASES) scores, Constant-Murley scores, Simple Shoulder Test (SST) scores, and Visual Analog Scale (VAS) scores postoperatively. Among 3 studies that included comparison with control groups of bipedal ambulators, no significant differences in outcomes were identified. The overall clinical complication rate was 17% for UEAs compared to 9.1% for controls. The rate of revision surgery was 7.7% for UEAs and 4.9% for bipedal ambulators. CONCLUSIONS: UEAs experience satisfactory pain relief, functional improvements, and good subjective outcomes following shoulder arthroplasty. However, complication and revision rates are higher compared to those for bipedal ambulators, and the majority of UEAs undergo reverse shoulder arthroplasty (RSA) compared to anatomic total shoulder arthroplasty (aTSA).

Anatomic TSA for B2 glenoids treated with asymmetric reaming has equivalent survivorship and patient outcomes compared to type A glenoids at mean 9 years follow-up.

BACKGROUND: Walch B2 glenoids can present a challenge to shoulder arthroplasty surgeons. Short-term studies have demonstrated that corrective reaming to 10° of retroversion in anatomic total shoulder arthroplasty (aTSA) can result in good outcomes, however there is little data reporting the long-term outcomes in this cohort. B2 glenoids treated with high-side reaming present a theoretical risk of early glenoid component failure as one may ream into the subchondral bone. This study aimed to demonstrate that 1) B2 glenoids treated with corrective reaming have durable results and 2) offer similar results to Walch A1/2 in long-term follow-up. METHODS: Patients who underwent aTSA by a single surgeon (E.L.F.) were identified from a shoulder arthroplasty registry. Inclusion criteria included Walch A1, A2 or B2 glenoid, a diagnosis of primary shoulder osteoarthritis, and a minimum radiographic and clinical follow-up of 5 years. 43 patients with B2 glenoids were compared to a cohort of 42 patients with A1 or A2 glenoids. Preoperative computed tomography (CT) and radiographs were utilized to assess deformity, glenoid version, and posterior subluxation of the humeral head. Postoperatively, patients were assessed with radiographs and patient-reported outcome measures including American Shoulder and Elbow Surgeons (ASES) score, Simple Shoulder Test (SST) score, and Visual Analog Scale (VAS). RESULTS: 85 shoulders (82 patients, 42 B2 and 43 A1/A2 glenoids) with an average follow-up of 9.4 years were included. In the B2 cohort, the average retroversion was 21.1° and posterior subluxation was 69.4% compared with 10.6°(p<0.001) and 57.5% (p<0.001) in the A1 or A2 cohort. The cohort demographics were similar except for male sex (B2 69.8% vs A1 or A2 37.2%, p=0.008). There was no difference between the cohorts in their improvement in ASES (p=0.807), SST (p=0.586), or VAS (p=0.930) scores. There was no difference in lateral humeral offset (p=0.889) or acromial humeral interval (p=0.468) between initial postoperative and final follow-up visits. Survivorship for B2 glenoids was 97.6%, 94.1% and 73.3% at 5, 10 and 15 years, respectively compared to 97.6%, 91.9% and 83.5% in type A glenoids. The revision rate was similar between the two groups (p=0.432). Lazarus score (p=0.682) and rates of humeral radiolucency (p=0.366) and humeral osteolysis (p=0.194) were similar between the two cohorts at final follow-up. CONCLUSION: Asymmetric reaming of patients with B2 glenoids is a reliable method of glenoid preparation with excellent mid- to long-term clinical results, patient reported outcomes, and low revision rates similar to their A1 and A2 counterparts.

Cemented vs. press-fit humeral stems: a matched cohort analysis at a mean follow-up of 10 years.

BACKGROUND: Although cementation of humeral stems has long been considered the gold standard for anatomic shoulder arthroplasty (aTSA), cementless, or press-fit, fixation offers a relatively cheaper and less demanding alternative, particularly in the setting of a revision procedure. However, this approach has been accompanied by concerns of implant loosening and high rates of radiolucency. In the present study, we performed a propensity-matched comparison of clinical and patient-reported outcomes between cemented and cementless fixation techniques for aTSA. We hypothesized that cemented fixation of the humeral component would have significantly better implant survival while providing comparable functional outcomes at final follow-up. METHODS: This study was a retrospective comparison of 50 shoulders undergoing aTSA: 25 using cemented humeral fixation vs. 25 using press-fit humeral fixation. Patients in the 2 groups were propensity matched according to age, sex, and preoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score. Primary outcome measures included range of motion (ROM) (forward elevation, external rotation, internal rotation), patient-reported outcomes (ASES, Simple Shoulder Test [SST], visual analog scale [VAS]), and implant survival. RESULTS: At baseline, the 2 fixation groups were similar in regard to age, sex, body mass index, preoperative ASES score, and surgical indication. Mean follow-up was 11.7 ± 4.95 years in the cemented cohort and 9.13 ± 3.77 years in the press-fit cohort (P = .045). Both groups demonstrated significant improvements postoperatively in all included ROM and patient-reported outcomes. However, press-fit patients reported significantly better VAS, ASES, and SST scores. Mean VAS pain score was 1.1 ± 1.8 in press-fit patients and 3.2 ± 3.0 in cemented patients (P = .005). The mean ASES score was 87.7 ± 12.4 in press-fit patients and 69.5 ± 22.7 in cemented patients (P = .002). Lastly, the mean SST score was 9.8 ± 3.1 in press-fit patients and 7.7 ± 3.7 in cemented patients (P = .040). Both fixation techniques provided lasting implant survivorship with only a single revision operation in each of the cohorts. CONCLUSION: Herein, we provide a propensity-matched, long-term comparison of patients receiving anatomic shoulder arthroplasty stratified according to humeral stem fixation technique. The results of this analysis illustrate that both types of humeral fixation techniques yield durable and significant improvements in shoulder function with similar rates of survival at 10 years of follow-up.

Mid-term outcomes following reverse total shoulder arthroplasty.

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

Improved functional, radiographic and patient-reported outcomes at midterm follow-up for shoulder arthroplasty patients 75 years and older.

Background: Current discussion centers around the appropriateness of shoulder arthroplasty in elderly patients, and whether anatomic and reverse total shoulder arthroplasty yield acceptable results in this population. The purpose of this study was to examine midterm outcomes in patients 75 years and older who underwent either procedure. Methods: A retrospective review was performed on patients who underwent anatomic total shoulder arthroplasty (aTSA) or reverse total shoulder arthroplasty (rTSA) between 2000 and 2018. Inclusion criteria was patient age ≥75 years at time of surgery and ≥1 years postoperative follow-up. Primary outcomes were differences in Simple Shoulder Test (SST), American Shoulder and Elbow Surgeons (ASES) score, Visual Analog Scale (VAS) pain score, and range of motion. A secondary outcome was revision surgery. Results: 22 patients who underwent aTSA and 17 patients who underwent rTSA were included. Mean age at surgery was 79 and 80 in the aTSA and rTSA groups, respectively. Mean postoperative follow-up was 6.6 years across both cohorts. Anatomic TSA patients experienced improvements in VAS (7 preop vs. 1 postop; p < 0.001), ASES (16 vs. 75; p < 0.001), and SST (2 vs. 8; p < 0.001) scores. Reverse TSA patients also experienced improvements in VAS (7 vs. 1; p < 0.001), ASES (29 vs. 74; p < 0.001), and SST (1 vs. 7; p < 0.001) scores. Anatomic TSA patients experienced improved external rotation (17° vs. 53°; p < 0.001), forward elevation (108° vs. 155°; p < 0.001), and internal rotation (L5 vs. T10; p < 0.001). Reverse TSA patients experienced improved forward elevation (52° vs. 126°; p < 0.001). 21 aTSA patients (100%) and 16 rTSA patients (94%) experienced survival free from revision. 100% of aTSA and rTSA patients experienced survival free from loosening. Conclusion: Both aTSA and rTSA can be performed in the elderly population with acceptable midterm outcomes, suggesting that implant survival and patient satisfaction have the potential to endure through the end of life. Level of evidence: IV.

Evaluating the effects of age on the long-term functional outcomes following anatomic total shoulder arthroplasty.

BACKGROUND: In the past decade, the number of anatomic total shoulder arthroplasty (aTSA) procedures has steadily increased. Patients over 65 years of age comprise the vast majority of recipients, and outcomes have been well documented; however, patients are opting for definitive surgical treatment at younger ages.We aim to report on the effects of age on the long-term clinical outcomes following aTSA. METHODS: Among the patients who underwent TSA, 119 shoulders were retrospectively analyzed. Preoperative and postoperative clinical outcome data were collected. Linear regression analysis (univariate and multivariate) was conducted to evaluate the associations of clinical outcomes with age. Kaplan-Meier curves and Cox regression analyses were performed to evaluate implant survival. RESULTS: At final follow-up, patients of all ages undergoing aTSA experienced significant and sustained improvements in all primary outcome measures compared with preoperative values. Based on multivariate analysis, age at the time of surgery was a significant predictor of postoperative outcomes. Excellent implant survival was observed over the course of this study, and Cox regression survival analysis indicated age and sex to not be associated with an increased risk of implant failure. CONCLUSIONS: When controlling for sex and follow-up duration, older age was associated with significantly better patient-reported outcome measures. Despite this difference, we noted no significant effects on range of motion or implant survival. Level of evidence: IV.

Does humeral fixation technique affect long-term outcomes of total shoulder arthroplasty?

BACKGROUND: For anatomic total arthroscopic repair, cementless humeral fixation has recently gained popularity. However, few studies have compared clinical, radiographic, and patient-reported outcomes between cemented and press-fit humeral fixation, and none have performed follow-up for longer than 5 years. In this study, we compared long-term postoperative outcomes in patients receiving a cemented versus press-fit humeral stem anatomic arthroscopic repair. METHODS: This study retrospectively analyzed 169 shoulders that required primary anatomic total shoulder arthroplasty (aTSA). Shoulders were stratified by humeral stem fixation technique: cementation or press-fit. Data were collected pre- and postoperatively. Primary outcome measures included range of motion, patient reported outcomes, and radiographic measures. RESULTS: One hundred thirty-eight cemented humeral stems and 31 press-fit stems were included. Significant improvements in range of motion were seen in all aTSA patients with no significant differences between final cemented and press-fit stems (forward elevation: P=0.12, external rotation: P=0.60, and internal rotation: P=0.77). Patient reported outcome metrics also exhibited sustained improvement through final follow-up. However, at final follow-up, the press-fit stem cohort had significantly better overall scores when compared to the cemented cohort (visual analog score: P=0.04, American Shoulder and Elbow Surgeon Score: P<0.01, Simple Shoulder Test score: P=0.03). Humeral radiolucency was noted in two cemented implants and one press-fit implant. No significant differences in implant survival were observed between the two cohorts (P=0.75). CONCLUSIONS: In this series, we found that irrespective of humeral fixation technique, aTSA significantly improves shoulder function. However, within this cohort, press-fit stems provided significantly better outcomes than cemented stems in terms of patient reported outcome scores. Level of evidence: III.

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

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

Rice-Body Synovitis, Foreign Body Reaction, and Rotator Cuff Failure After Subacromial Balloon Spacer Augmentation of a Rotator Cuff Repair: A Case Report.

CASE: A 66-year-old woman presented with shoulder pain and weakness 4 months after augmentation of a rotator cuff repair with a Stryker InSpace subacromial balloon spacer. A magnetic resonance imaging (MRI) demonstrated a failed rotator cuff repair, large effusion with rice bodies, synovitis, axillary lymphadenopathy, loose anchors, and erosive changes to the greater tuberosity. Arthroscopy revealed balloon fragmentation surrounded by diffusely hyperemic synovium without repairable cuff tissue. Final cultures proved negative for infection. Histologic evaluation revealed ulcerated synovium with diffuse chronic and focal acute inflammation. CONCLUSION: Despite promising early results, augmentation of a rotator cuff repair with a subacromial balloon spacer introduces a risk of inflammatory reaction that may mimic a deep infection and compromise rotator cuff healing.

A comparison of pegged and keeled glenoid clinical outcomes at long-term follow-up after total shoulder arthroplasty.

Background: The two main glenoid types used in total shoulder arthroplasty (TSA) are the pegged and keeled glenoid designs. We aimed to determine if a pegged glenoid is superior to a keeled glenoid at long-term follow-up as measured by range of motion (ROM), patient reported outcomes (PROs), and radiographic glenoid loosening. Methods: We retrospectively reviewed all patients undergoing TSA by a single surgeon at an urban, academic hospital. The cohort was stratified into two groups based on glenoid type - one group consisting of keeled implants and a second group consisting of pegged implants. For each patient, forward elevation (FE), internal rotation (IR), external rotation (ER), visual analog scale (VAS), American Shoulder and Elbow Surgeons (ASES) shoulder score, and simple shoulder test (SST) scores were collected preoperatively and at the most recent follow-up visit. Radiographic variables included acromiohumeral interval (AHI) and glenoid loosening. Results: After applying exclusion criteria, 144 TSAs were included in our study. Of these, 42 (29.2%) had keeled glenoids and 102 (70.8%) had pegged glenoids. Patients with a pegged glenoid implant were older (67.4 vs. 60.7 years; p < 0.001) and had a shorter follow-up time (9.3 vs. 14.4 years; p < 0.001) than patients with a keeled glenoid implant. At the most recent follow-up visit, there were no significant differences among postoperative FE, ER, AHI, or PROs. However, pegged glenoid implants provided significantly more internal rotation (T11 vs. L1; p = 0.010) and were less likely to show evidence of radiographic glenoid loosening (16.7% vs. 42.9%; p=<0.001). Revision rates were not significantly different between the pegged and keeled groups (6.9% vs. 14.3%; p = 0.158). Conclusion: Although a pegged design correlated with superior internal rotation and less radiographic glenoid loosening, both pegged and keeled glenoid designs offered favorable long-term clinical outcomes following TSA over the long-term.

The impact of tobacco use on clinical outcomes and long-term survivorship after anatomic total shoulder arthroplasty.

Introduction: Postoperative outcomes following total shoulder arthroplasty can be affected by preoperative health factors such as tobacco usage. Methods: The charts of patients who underwent anatomic total shoulder arthroplasty were retrospectively analyzed and stratified based on smoking status. The primary data included range of motion and patient reported outcomes. Additionally, demographic, radiographic, and survivorship analyses were conducted. All data were analyzed using statistical inference. Results: There were 78, 49, and 16 non-smoker, former smoker, and current smoker shoulders respectively with no significant differences in sex, American Society of Anesthesiologists status, body mass index, or mean follow-up time (average: 10.7 yrs). Smokers (51.5 ± 10.4 years) were younger than both non-smokers (64.9 ± 8.1 years; p < 0.01) and former smokers (65.1 ± 9.1years; p < 0.01) at the time of surgery. For non-smokers and former smokers, all range of motion and patient reported outcome scores significantly improved. Smokers reported significant improvements in all patient reported outcomes and external and internal rotation. Visual Analog Scale, American Shoulder and Elbow, and Simple Shoulder Test scores were lower for smokers comparatively, but these differences did not reach significance. Forward elevation was higher postoperatively for non-smokers (149.7o ± 17.2o) and former smokers (147.1o ± 26.0o) compared to current smokers (130.9o ± 41.2o; p = 0.017). No differences between the cohorts were found in the radiographic analysis. Revision rates were lower in the non-smoking cohort (7.7%) compared to both former (20.4%; p = 0.036) and current smokers (37.5%; p < 0.01). Survival curves showed that non-smoker implants lasted longer than those of current smokers. Conclusion: After a decade, patients generally had improved shoulder range of motion, functionality, and pain regardless of smoking status. However, current smokers required shoulder replacements sooner and revision surgery more frequently.

Does body mass index influence long-term outcomes after anatomic total shoulder arthroplasty?

BACKGROUND: As of 2018, upwards of 42% of the US adult population was considered obese based on body mass index (BMI) scales. With the annual number of total joint replacements increasing, this study aimed to evaluate the impact BMI has on anatomic total shoulder arthroplasty (aTSA) outcomes. METHODS: This was a retrospective analysis of 128 shoulders requiring primary aTSA. Patients were stratified into 3 cohorts based on their BMI at surgery: underweight/normal weight (U/NW; BMI ≤25.0), overweight (25.0 < BMI ≤ 30.0), and obese (BMI >30.0). BMI was separately analyzed as a continuous variable. Clinical endpoints were range of motion scores, including forward elevation, external rotation, and internal rotation, and patient-reported outcomes, including visual analog scale (VAS) scores, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) scores, and the Simple Shoulder Test (SST). Survivorship curves were calculated using Kaplan-Meier analysis. RESULTS: Forty-four, 50, and 34 patient shoulders were in the U/NW, overweight, and obese cohorts, respectively. The mean follow-up time was 11.4 years. The U/NW cohort had more females (73%) compared with the overweight (34%; P = .0030) and obese (35%; P = .0015) groups; no differences were seen in revision rates. BMI was negatively correlated with age at surgery (r = -0.19, P = .014); it was not correlated with any of the 6 postoperative clinical endpoints. All 3 cohorts saw significant improvements in forward elevation, external rotation, internal rotation and VAS, ASES, and SST scores when compared preoperatively to postoperatively (P < .001). There were no significant differences between the 3 cohorts with respect to postoperative range of motion. Postoperative ASES scores were higher for the overweight cohort (82.6 ± 18.6) compared with both the U/NW (63.0 ± 25.1) and obese cohorts (70.5 ± 26.8) (P < .001). The overweight cohort also had higher SST (P = .0012) postoperative scores compared with the U/NW and obese cohorts; VAS scores were comparable between groups (P = .12). The nonobese (BMI <30) group (n = 94) showed 5-, 10-, and 15-year implant survival of 98.9%, 94.9%, and 83.9%, respectively compared to 97.1%, 93.7%, and 87.0% in the obese (BMI ≥30) group (n = 34). The log rank test revealed no significant difference in survival curves (P = .82). CONCLUSION: To our knowledge, this is the longest follow-up study analyzing clinical endpoints stratified by BMI for aTSA. We saw that patients with a higher BMI required shoulder replacement at a significantly younger age. However, we also report that regardless of BMI, all patients saw significant improvements in patient-reported outcomes and range of motion scores postoperatively.

Incidence and risk factors for pseudosubluxation of the humeral head following proximal humerus fracture.

Background: Humeral head pseudosubluxation (HHPS) in relation to the glenohumeral joint is a common finding following fractures of the proximal humerus. The temporary inferior subluxation of the humeral head may be secondary to a transient axillary nerve neuropraxia, pain inhibition of the deltoid, or hemarthrosis or capsular disruption that alters the physiologically negative pressure in the glenohumeral joint. Despite the frequency of this finding, it is not well described in the literature. This study sought to describe the incidence, risk factors, and rate of resolution of HHPS following proximal humerus fracture. Methods: The practice of two fellowship-trained shoulder and elbow surgeons was queried for proximal humerus fractures. Patient radiographs were reviewed at the time of injury and all subsequent follow-ups through one year after injury. Data collection included the presence of HHPS, type of fracture based on the Neer classification, operative vs. nonoperative management, and resolution of HHPS. Exclusion criteria included skeletally immature patients, fracture-dislocations, patients treated with reverse shoulder arthroplasty, inadequate follow-up, or those patients with incorrect International Classification of Diseases coding. Results: The incidence of HHPS was 20.0% (103 out of 515 patients) overall. Patients who required surgical intervention were more likely to develop pseudosubluxation than those who were treated conservatively (P < .001). There was an increasing incidence of pseudosubluxation based on the Neer classification, with 0-part fractures demonstrating a 2.56% (2/78) rate, whereas 4-part fractures were found to have HHPS in 35.1% (20/57) of cases (P < .001). All patients were found to have resolution of their HHPS at the final follow-up or one year after injury. None of age, sex, obesity, or injury to the dominant arm was associated with the occurrence of HHPS. There was, however, a statistically significant difference in the body mass index of those who developed HHPS (28.4, ± 5.77) vs. those who did not (26.2, ± 5.32, P < .01). Conclusion: This retrospective radiographic study is the largest to date investigating the incidence of HHPS following proximal humerus fracture and first to correlate with Neer classification and operative intervention. We found that HHPS occurs in one-fifth of acute proximal humerus fractures and resolves regardless of intervention. More complex fractures, including those with increasing Neer parts or requiring operative intervention, developed HHPS at higher rates than simpler fracture patterns. This study will help both general orthopedists as well as shoulder surgeons understand the epidemiology of HHPS and provide reassurance to patients that PS is a benign finding with expected spontaneous resolution by one year.

Surgical Management of Complex Adult Monteggia Fractures.

Monteggia fractures classically involve a proximal ulna fracture with an associated radial head dislocation. The presence of radial head/neck fracture and comminution of the proximal ulna with coronoid involvement elevates the complexity of surgical reconstruction considerably. The Jupiter classification captures this injury pattern as a subgroup of Bado posterior Monteggia lesions. Access to the critical coronoid fragment can be problematic from the posterior approach and may result in tenuous reduction and fixation, directly affecting the functional outcome. Multiple operative techniques have been described to address the broad spectrum of injuries seen in Monteggia fractures. This article will cover commonly used fixation techniques for Monteggia fractures with a comprehensive literature review, including technical tips, outcomes, and complications.

Comparison of machine learning techniques to predict unplanned readmission following total shoulder arthroplasty.

BACKGROUND: Machine learning (ML) techniques have been shown to successfully predict postoperative complications for high-volume orthopedic procedures such as hip and knee arthroplasty and to stratify patients for risk-adjusted bundled payments. The latter has not been done for more heterogeneous, lower-volume procedures such as total shoulder arthroplasty (TSA) with equally limited discussion around strategies to optimize the predictive ability of ML algorithms. The purpose of this study was to (1) assess which of 5 ML algorithms best predicts 30-day readmission, (2) test select ML strategies to optimize the algorithms, and (3) report on which patient variables contribute most to risk prediction in TSA across algorithms. METHODS: We identified 9043 patients in the American College of Surgeons National Surgical Quality Improvement Database who underwent primary TSA between 2011 and 2015. Predictors included demographics, comorbidities, laboratory data, and intraoperative variables. The outcome of interest was 30-day unplanned readmission. Five ML algorithms-support-vector machine (SVM), logistic regression, random forest (RF), an adaptive boosting algorithm, and neural network-were trained on the derivation cohort (2011-2014 TSA patients) to predict 30-day unplanned readmission rates. After training, weights for each respective model were fixed and the classifiers were evaluated on the 2015 TSA cohort to simulate a prospective evaluation. C-statistic and f1 scores were used to assess the performance of each classifier. After evaluation, features were removed independently to assess which features most affected classifier performance. RESULTS: The derivation and validation cohorts comprised 5857 and 3186 primary TSA patients, respectively, with similar demographics, comorbidities, and 30-day unplanned readmission rates (2.9% vs. 2.7%). Of the ML algorithms, SVM performed the worst with a c-statistic of 0.54 and an f1-score of 0.07, whereas the random-forest classifier performed the best with the highest c-statistic of 0.74 and an f1-score of 0.18. In addition, SVM was most sensitive to loss of single features, whereas the performance of RF did not dramatically decrease after loss of single features. Within the trained RF classifier, 5 variables achieved weights >0.5 in descending order: high bilirubin (>1.9 mg/dL), age >65, race, chronic obstructive pulmonary disease, and American Society of Anesthesiologists' scores ≥3. In our validation cohort, we observed a 2.7% readmission rate. From this cohort, using the RF classifier we were then able to identify 436 high-risk patients with a predicted risk score >0.6, of whom 36 were readmitted (readmission rate of 8.2%). CONCLUSION: Predictive analytics algorithms can achieve acceptable prediction of unplanned readmission for TSA with the RF classifier outperforming other common algorithms.

Peripheral nerve block use in inpatient and outpatient shoulder arthroplasty: a population-based study evaluating utilization and outcomes.

BACKGROUND: Peripheral nerve block (PNB) is an effective pain management option after shoulder arthroplasty with increasing popularity over the past decade. Large-scale US data in shoulder arthroplasties are lacking, especially regarding impacts on opioid utilization. This population-based study aimed to evaluate PNB utilization patterns and their effect on outcomes after inpatient and outpatient shoulder arthroplasty. METHODS: This retrospective cohort study used data from the nationwide Premier Healthcare claims database (2006-2016). This study includes n=94 787 and n=3293 inpatient and outpatient (total, reverse and partial) shoulder arthroplasty procedures. Multivariable mixed-effects models estimated associations between PNB use and opioid utilization in oral morphine equivalents and cost of hospitalization/stay. For the inpatient group, additional outcome measures were length of stay (LOS), admission to a skilled nurse facility, 30-day readmission, combined complications and naloxone use (as a proxy for opioid-related complications). We report OR (or % change for continuous variables) and 95% CIs. RESULTS: Overall, PNB was used in 19.1% (n=18 144) and 20.8% (n=685) of inpatient and outpatient shoulder arthroplasties, respectively, with an increasing trend for inpatient procedures. PNB utilization was consistently associated with lower (up to -14.0%, 95% CI -15.4% to -12.5% decrease, with median 100 and 90 oral morphine equivalents for inpatient and outpatient procedures) opioid utilization on the day of surgery with more potent effects seen for inpatient shoulder arthroplasties. Other outcomes were minimally impacted. DISCUSSION: In this first national study on PNB use in shoulder arthroplasty, we found increasing PNB use among specifically, inpatient procedures, resulting in particularly reduced opioid use on the day of surgery. While our findings may support PNB use in shoulder arthroplasty, its current low utilization and trends towards more outpatient procedures necessitate continuous monitoring of more extensive benefits.

Opioid Consumption and Time to Return to Work After Percutaneous Osteotomy in Foot Surgery.

Surgeries involving the foot and ankle are painful procedures, with many patients unwilling to discontinue prescribed narcotics at 3 months postoperatively. Percutaneous techniques allow for smaller incisions and minimal soft tissue disruption. Fifty consecutive patients underwent outpatient percutaneous foot surgery. Data were collected on pain medication taken and time to return to work. A mean of 3.3 tablets of oxycodone were consumed during the first 2 weeks. No patient was taking narcotics after 2 weeks. Mean time to return to work was 18.9 days. Percutaneous foot and ankle surgery led to a significant reduction in narcotic consumption. [Orthopedics. 2020;43(4):e334-e337.].

Risk factors for heterotopic ossification in operatively treated proximal humeral fractures.

AIMS: Heterotopic ossification (HO) is a potentially devastating complication of the surgical treatment of a proximal humeral fracture. The literature on the rate and risk factors for the development of HO under these circumstances is lacking. The aim of this study was to determine the incidence and risk factors for the development of HO in these patients. METHODS: A retrospective analysis of 170 patients who underwent operative treatment for a proximal humeral fracture between 2005 and 2016, in a single institution, was undertaken. The mean follow-up was 18.2 months (1.5 to 140). The presence of HO was identified on follow-up radiographs. RESULTS: The incidence of HO was 15% (n = 26). Our multivariate model revealed that male sex (odds ratio (OR) 3.57, 95% confidence interval (CI) 1.30 to 9.80 compared to female) and dislocation as the initial injury (OR 5.01, 95% CI 1.31 to 19.22) were significantly associated with the formation of HO (p < 0.05) while no significant associations were seen for the age of the patient, the characteristics of the injury, or the type of operative treatment. CONCLUSION: This retrospective radiological study is the first to investigate the association between the method of surgical treatment for a proximal humeral fracture and the formation of HO postoperatively. We found that male sex and dislocation as the initial injury were risk factors for HO formation, whereas the method of surgical treatment, the age of the patient, and the pattern of the fracture were not predictive of HO formation. While additional studies are needed, these findings can help to identify those at an increased risk for HO formation under these circumstances. Cite this article: Bone Joint J 2020;102-B(4):539-544.

Second physician review of radiographs after wrist and ankle reductions offers limited utility to clinical management.

PURPOSE: The purpose of this study is to determine the clinical utility of second-physician review of radiographs obtained after reduction of distal radius and ankle fractures. METHODS: Fifty consecutive ankle and distal radius fractures requiring reduction were reviewed. The time from post-reduction radiograph to second-physician interpretation was obtained. The second-physicians' interpretation was evaluated for clinically influential information. Patients requiring a repeat reduction were identified, and the timing of the repeat reduction radiograph was compared with the timing of the second-physician interpretation of the initial post-reduction radiograph. RESULTS: The mean time of second-physician interpretation for post reduction ankle radiographs was 6 h and 47 min (range 4 min to 43 h and 3 min). Eleven of 50 (22%) interpretations of post reduction ankle radiographs commented on acceptability of reduction. The mean time of second-physician interpretation for post reduction distal radius radiographs was 5 h and 34 min (range 8 min to 22 h and 59 min). Seven of 50 (14%) interpretations of post reduction distal radius radiographs commented on acceptability of reduction. Three distal radius (6%) and 8 ankle fractures (16%) required repeat reduction. Repeat reductions were completed in 10/11 cases (91%) before the second-physician review of the initial post reduction radiograph was obtained. In only 1 case of repeat reduction was the second-physician review of the post reduction radiograph available before repeat reduction was attempted. CONCLUSION: The timing and quality of second-physician review of post-reduction radiographs offers little utility to the clinical management of ankle and distal radius fractures.