Using time-weighted average change from baseline of SARS-CoV-2 viral load to assess impact of hydroxychloroquine as postexposure prophylaxis and early treatment for COVID-19.

Two randomized controlled trials demonstrated no clinical benefit of hydroxychloroquine (HCQ) for either postexposure prophylaxis or early treatment of SARS-CoV-2 infection. Using data from these studies, we calculated the time-weighted average change from baseline SARS-CoV-2 viral load and demonstrated that HCQ did not affect viral clearance.

Effects of Air Pollution and Other Environmental Exposures on Estimates of Severe Influenza Illness, Washington, USA.

Ecologic models of influenza burden may be confounded by other exposures that share winter seasonality. We evaluated the effects of air pollution and other environmental exposures in ecologic models estimating influenza-associated hospitalizations. We linked hospitalization data, viral surveillance, and environmental data, including temperature, relative humidity, dew point, and fine particulate matter for 3 counties in Washington, USA, for 2001-2012. We used negative binomial regression models to estimate the incidence of influenza-associated respiratory and circulatory (RC) hospitalizations and to assess the effect of adjusting for environmental exposures on RC hospitalization estimates. The modeled overall incidence rate of influenza-associated RC hospitalizations was 31/100,000 person-years. The environmental parameters were statistically associated with RC hospitalizations but did not appreciably affect the event rate estimates. Modeled influenza-associated RC hospitalization rates were similar to published estimates, and inclusion of environmental covariates in the model did not have a clinically important effect on severe influenza estimates.

Patterns of Hospital Bypass and Interhospital Transfer Among Patients With Heart Failure.

BACKGROUND: We describe how patient characteristics influence hospital bypass, interhospital transfer, and in-hospital mortality in patients with heart failure in Washington. Rural patients with heart failure may bypass their nearest hospital or be transferred for appropriate therapies. The frequency, determinants, and outcomes of these practices remain uncharacterized. METHODS AND RESULTS: Mean excess travel times based on hospital and patient residence ZIP codes were calculated using published methods. Hospitals and servicing areas were coded based on bed size and ZIP code, respectively. Transfer patterns were analyzed using bootstrap inference for clusters. Analysis of mortality and transfer-associated factors was performed using logistic regression with generalized estimating equations. There were 48,163 patients, representing 1106 instances of transfer, studied. The mean excess travel time increased 7.14 minutes per decrease in population density (metropolitan, micropolitan, small town, rural; P < .0001). The rural mean excess travel time was greatest at 28.56 minutes. Transfer likelihood increased with younger age, male gender, admitting hospital rurality, higher Charlson Comorbidity Index, and stroke. Transfer was less likely among women (odds ratio [OR], 0.82; 95% confidence interval [CI], 0.72-0.94) and patients over 70 years old (OR, 0.15-0.46; 95% CI, 0.10-0.65). Adjusting for comorbidities and transfer propensity, transfer exhibited a stronger association with mortality than any other measured patient risk factor (OR, 2.15; 95% CI, 1.69-2.73), excluding stroke (OR, 7.09; 95% CI, 4.99-10.06). CONCLUSIONS: Rural hospital bypass is prevalent among patients with heart failure, although its clinical significance is unclear. Female and older patients were found to have a lesser likelihood of transfer adjusted for other factors. Interhospital transfer is associated with increased mortality when adjusted for comorbidities.

Forecasting a Crisis: Machine-Learning Models Predict Occurrence of Intraoperative Bradycardia Associated With Hypotension.

BACKGROUND: Predictive analytics systems may improve perioperative care by enhancing preparation for, recognition of, and response to high-risk clinical events. Bradycardia is a fairly common and unpredictable clinical event with many causes; it may be benign or become associated with hypotension requiring aggressive treatment. Our aim was to build models to predict the occurrence of clinically significant intraoperative bradycardia at 3 time points during an operative course by utilizing available preoperative electronic medical record and intraoperative anesthesia information management system data. METHODS: The analyzed data include 62,182 scheduled noncardiac procedures performed at the University of Washington Medical Center between 2012 and 2017. The clinical event was defined as severe bradycardia (heart rate <50 beats per minute) followed by hypotension (mean arterial pressure <55 mm Hg) within a 10-minute window. We developed models to predict the presence of at least 1 event following 3 time points: induction of anesthesia (TP1), start of the procedure (TP2), and 30 minutes after the start of the procedure (TP3). Predictor variables were based on data available before each time point and included preoperative patient and procedure data (TP1), followed by intraoperative minute-to-minute patient monitor, ventilator, intravenous fluid, infusion, and bolus medication data (TP2 and TP3). Machine-learning and logistic regression models were developed, and their predictive abilities were evaluated using the area under the ROC curve (AUC). The contribution of the input variables to the models were evaluated. RESULTS: The number of events was 3498 (5.6%) after TP1, 2404 (3.9%) after TP2, and 1066 (1.7%) after TP3. Heart rate was the strongest predictor for events after TP1. Occurrence of a previous event, mean heart rate, and mean pulse rates before TP2 were the strongest predictor for events after TP2. Occurrence of a previous event, mean heart rate, mean pulse rates before TP2 (and their interaction), and 15-minute slopes in heart rate and blood pressure before TP2 were the strongest predictors for events after TP3. The best performing machine-learning models including all cases produced an AUC of 0.81 (TP1), 0.87 (TP2), and 0.89 (TP3) with positive predictive values of 0.30, 0.29, and 0.15 at 95% specificity, respectively. CONCLUSIONS: We developed models to predict unstable bradycardia leveraging preoperative and real-time intraoperative data. Our study demonstrates how predictive models may be utilized to predict clinical events across multiple time intervals, with a future goal of developing real-time, intraoperative, decision support.

Cutaneous microbiology of patients having primary shoulder arthroplasty.

BACKGROUND: Shoulder periprosthetic infections are predominantly caused by bacteria residing in the skin of healthy individuals. Knowledge of the factors associated with the loads of the different cutaneous bacteria in individuals having shoulder arthroplasty may help identify patients at higher risk of periprosthetic infection and help guide preventive measures. For this reason, we tested the hypothesis that easy-to-obtain preoperative characteristics were significantly associated with the cutaneous microbiology and the loads of specific bacteria in shoulders having joint replacement. METHODS: This study identified the microbiology of the unprepared epidermal skin surface and of the dermal edge freshly incised at surgery in 332 patients having primary shoulder arthroplasty. The load of bacteria in each sample was characterized as a value based on the laboratory report: 0 for "no growth"; 0.1 for "one colony only" or for "broth only"; and 1, 2, 3, and 4 for 1+, 2+, 3+, and 4+ growth, respectively. The relationships between preoperative patient characteristics and these semiquantitative results of the cutaneous cultures were analyzed. RESULTS: Cultures of the unprepared epidermal skin surface showed positive results for a wide variety of organisms, including Cutibacterium in 72%, coagulase-negative Staphylococcus in 61%, and a spectrum of other organisms in 32%. By contrast, cultures of the freshly incised dermal edge showed a great preponderance of Cutibacterium (34%) in comparison to low levels of coagulase-negative Staphylococcus (8%) and other organisms (2%). An increased dermal load of Cutibacterium was significantly associated with male sex, younger patient age, American Society of Anesthesiologists class 1, use of testosterone supplements, prior shoulder surgery, and higher Cutibacterium loads on the unprepared skin surface. CONCLUSIONS: Although the microbiology of the unprepared skin surface is diverse, the same is not true for the freshly incised dermis, where Cutibacterium is the predominant organism. Readily available preoperative patient characteristics are significantly associated with the load of Cutibacterium in the incised dermis. Preoperative cultures of the unprepared skin surface appear to be a new method for predicting the type and load of bacteria found in the freshly incised dermis at the time of surgery. Additional studies are needed to determine whether preoperative cultures of the unprepared epidermal skin surface can provide a method for identifying patients at increased risk of shoulder periprosthetic infections.

Industry payments to authors of Journal of Shoulder and Elbow Surgery shoulder arthroplasty manuscripts are accurately disclosed by most authors and are not significantly associated with better reported treatment outcomes.

BACKGROUND: Author transparency in disclosing potential conflicts of interest when reporting outcomes for shoulder arthroplasty implants is important. Using the Centers for Medicare & Medicaid Services Open Payments Program (OPP) database, we analyzed articles in the Journal of Shoulder and Elbow Surgery to evaluate (1) discrepancies between the stated conflicts of interest and associated payments recorded in the database, (2) the magnitude and types of payments received, and (3) possible relationships between industry financial support and positive study outcomes. METHODS: Articles reporting clinical outcomes of shoulder arthroplasty from 2016 and 2017 were reviewed. Articles identifying a specific shoulder arthroplasty implant and having at least 1 author based in the United States were included. Payment types, amounts, and sources were extracted from disclosure statements in the manuscript and considered relevant if they were received from the implant manufacturer. Published disclosure statements were compared against the OPP database. Study outcomes demonstrating a clinical benefit were considered "positive." Payments to authors reporting positive outcomes were compared with those reporting nonpositive outcomes. RESULTS: Implant manufacturers provided $16,051,261 to authors of shoulder arthroplasty publications over a 2-year period. Approximately half of senior authors (46%) received royalty payments, more than 90% of which ($14,910,873; 93%) were reported in disclosure statements. Although authors of articles with positive outcomes received greater payments than those reporting nonpositive outcomes, these differences were not statistically significant. CONCLUSION: The majority of author disclosure statements accurately reflected the OPP data. Payments were not significantly associated with positive outcomes reported for the specific implant.

Factors predictive of Cutibacterium periprosthetic shoulder infections: a retrospective study of 342 prosthetic revisions.

BACKGROUND: Cutibacterium are the most common cause of periprosthetic shoulder infections, as defined by ≥2 deep cultures. Established Cutibacterium periprosthetic infections cannot be resolved without prosthesis removal. However, the decision for implant removal must be made from an assessment of infection risk before the results of intraoperative cultures are finalized. We hypothesized that the risk for a Cutibacterium infection is associated with characteristics that are available at the time of revision arthroplasty. METHODS: In a retrospective review of 342 patients having prosthetic revisions between 2006 and 2018 for whom definitive deep culture results were available, we used univariate and multivariate analyses to compare the preoperative and intraoperative characteristics of 101 revisions with Cutibacterium periprosthetic infections to the characteristics of 241 concurrent revisions not meeting the definition of infection. RESULTS: Patients with definite Cutibacterium periprosthetic infections were younger (59 ± 10 vs. 64 ± 12, P < .001), were more likely to be male (91% vs. 44%, P < .001), were more likely to have had their index procedure performed for primary osteoarthritis (54% vs. 39%, P = .007), were more likely to be taking testosterone supplements (8% vs. 2%, P = .02), had lower American Society of Anesthesiologists scores (1.9 ± 0.7 vs. 2.3 ± 0.7, P < .001), and had lower body mass indices (29 ± 5 vs. 31 ± 7, P = .005). Patients with definite Cutibacterium periprosthetic infections also had significantly higher preoperative loads of Cutibacterium on their unprepared skin surface (1.7 ± 0.9 vs. 0.4 ± 0.8, P < .001) and were more likely to have the surgical finding of synovitis (41% vs. 16%, P < .001). CONCLUSIONS: The risk of definite Cutibacterium periprosthetic infections is associated with observations that can be made before or at the time of revision arthroplasty.

Impact of previous non-arthroplasty surgery on clinical outcomes after primary anatomic shoulder arthroplasty.

BACKGROUND: The objectives of this study were to address the following questions regarding previous non-arthroplasty surgery prior to primary anatomic shoulder arthroplasty (either total shoulder arthroplasty [TSA] or ream-and-run arthroplasty): (1) To what degree is primary anatomic shoulder arthroplasty after prior non-arthroplasty surgery associated with inferior clinical outcomes and higher revision rates compared with arthroplasty without previous surgery? (2) Does type, approach, or timing of previous surgery affect outcomes after anatomic arthroplasty? METHODS: A retrospective review of a primary shoulder arthroplasty database was performed and identified 640 patients undergoing anatomic shoulder arthroplasty (345 TSAs and 295 ream-and-run arthroplasties). Of these patients, 183 (29%) underwent previous non-arthroplasty surgery. Baseline and demographic information, 2-year postoperative outcome scores, and revision surgical procedures with associated culture results were collected. RESULTS: In patients undergoing TSA, previous non-arthroplasty surgery was associated with a significantly lower 2-year Simple Shoulder Test (SST) score (P = .010), percentage maximum possible improvement (MPI) (P = .024), and Single Assessment Numeric Evaluation (SANE) score (P < .001) and a higher rate of reoperation (P < .001). In patients undergoing ream-and-run arthroplasty, previous non-arthroplasty surgery was associated with a nonsignificantly lower 2-year SST score, percentage MPI, and SANE score and higher reoperation rate. Prior fracture surgery carried a higher risk of reoperation than other types of surgery including rotator cuff repair and instability surgery. Among TSA and ream-and-run arthroplasty cases with prior non-arthroplasty surgery, prior open surgery and the time interval from most recent surgery were associated with nonsignificant differences in the 2-year SST score, percentage MPI, SANE score, and revision risk. CONCLUSION: Previous surgery is associated with inferior clinical outcomes and higher revision rates in patients undergoing index TSA but not in those undergoing the ream-and-run procedure. Patients with previous fracture surgery carry the highest risk of reoperation.

Psychometric Evaluation of a Pain Intensity Measure for Persons with Dementia.

OBJECTIVE: The goal of this study was to conduct initial psychometric analyses of a seven-item pain intensity measure for persons with dementia (PIMD) that was developed using items from existing pain observational measures. DESIGN AND METHODS: We evaluated validity by examining associations with an expert clinician's pain intensity rating (ECPIR) and an established pain observation tool (Mobilization Observation Behaviour Intensity Dementia [MOBID]). We also examined correlations between the PIMD and known correlates of pain: depression, sleep disturbances, agitation, painful diagnoses, and caregiver pain reports. We examined the differences between PIMD scores for "at rest" and "during movement" observations. We assessed reliability by calculating Cronbach's alpha and estimating inter-rater reliability using intraclass correlations (ICCs). Finally, we examined whether six additional "recent changes in behavior" items improved the PIMD's ability to predict expert clinicians' pain ratings. SETTING: Sixteen nursing homes located in Alabama, Georgia, Pennsylvania, and New Jersey. PARTICIPANTS: One hundred ninety residents with moderate to severe cognitive impairment, mean age of 84 years, 49.5% female, and 70% white. RESULTS: PIMD during movement scores were highly correlated with the ECPIR and overall MOBID scores. As expected, there were large differences between at rest and during movement PIMD scores. Associations of PIMD with known correlates of pain were generally low and statistically nonsignificant. Internal consistency was supported with a Cronbach alpha of 0.72 and an inter-rater ICC of 0.82 for during movement PIMD scores. CONCLUSIONS: Initial evaluation of the PIMD supports its validity and reliability. Additional testing is needed to evaluate the tool's sensitivity to changes in pain intensity.

Developing a Pain Intensity Measure for Persons with Dementia: Initial Construction and Testing.

OBJECTIVE: The goal of this study was to identify a limited set of pain indicators that were most predicive of physical pain. We began with 140 items culled from existing pain observation tools and used a modified Delphi approach followed by statistical analyses to reduce the item pool. METHODS: Through the Delphi Method, we created a candidate item set of behavioral indicators. Next, trained staff observed nursing home residents and rated the items on scales of behavior intensity and frequency. We evaluated associations among the items and expert clinicians' assessment of pain intensity. SETTING: Four government-owned nursing homes and 12 community nursing homes in Alabama and Southeastern Pennsylvania. PARTICIPANTS: Ninety-five residents (mean age = 84.9 years) with moderate to severe cognitive impairment. RESULTS: Using the least absolute shrinkage and selection operator model, we identified seven items that best predicted clinicians' evaluations of pain intensity. These items were rigid/stiff body or body parts, bracing, complaining, expressive eyes, grimacing, frowning, and sighing. We also found that a model based on ratings of frequency of behaviors did not have better predictive ability than a model based on ratings of intensity of behaviors. CONCLUSIONS: We used two complementary approaches-expert opinion and statistical analysis-to reduce a large pool of behavioral indicators to a parsimonious set of items to predict pain intensity in persons with dementia. Future studies are needed to examine the psychometric properties of this scale, which is called the Pain Intensity Measure for Persons with Dementia.

Psychometric Evaluation of the MOBID Dementia Pain Scale in U.S. Nursing Homes.

PURPOSE: The Mobilization-Observation-Behavior-Intensity-Dementia (MOBID) Pain Scale is an observational tool in which raters estimate pain intensity on a 0-10 scale following five standardized movements. The tool has been shown to be valid and reliable in northern European samples and could be useful in the United States (US) for research and clinical purposes. The goal of this study was to examine the validity and reliability of the MOBID among English-speaking nursing home residents in the US. DESIGN: Cross-sectional study. SETTINGS: Sixteen nursing homes in Pennsylvania, New Jersey, Georgia and Alabama. PARTICIPANTS: One hundred thirty-eight older adults with dementia and moderate to severe cognitive impairment. METHODS: Validity was evaluated using Spearman correlations between the MOBID overall pain intensity score and 1) an expert clinician's pain intensity rating (ECPIR), 2) nursing staff surrogate pain intensity ratings, and 3) known correlates of pain. We assessed internal consistency by Cronbach's alpha. RESULTS: MOBID overall scores were significantly associated with expert clinician's rating of current and worst pain in the past week (rho = 0.54, and 0.57; p < .001, respectively). Statistically significant associations also were found between the MOBID overall score and nursing staff current and worst pain intensity ratings as well as the Cornell Scale for Depression in Dementia (rho = 0.29; p < .001). Internal consistency was acceptable (α = 0.83). CONCLUSIONS AND CLINICAL IMPLICATIONS: Result of this study support the use of the MOBID in English-speaking staff and residents in the US. Findings also suggest that the tool can be completed by trained, nonclinical staff.

Radiographic outcomes of impaction-grafted standard-length humeral components in total shoulder and ream-and-run arthroplasty: is stress shielding an issue?

BACKGROUND: The purpose of this study was to evaluate humeral stress shielding in shoulder arthroplasties performed with a smooth, standard-length humeral stem fixed with impaction autografting. METHODS: Two-year outcomes were evaluated for 48 ream-and-run arthroplasties and 78 total shoulder arthroplasties (TSAs) performed at a single institution. Postoperative radiographs were analyzed for adaptive changes, calcar osteolysis, and component shift or subsidence. Radiographic outcomes were analyzed for associations with patient demographic characteristics, humeral stem filling ratios, and glenoid loosening; clinical outcomes were assessed using the Simple Shoulder Test. RESULTS: At 2 years after surgery, the ream-and-run procedures showed partial calcar osteolysis in 9 cases (19%). The TSAs showed partial calcar osteolysis in 19 cases (24%) and complete calcar osteolysis in 2 (3%). Humeral component subsidence or component shift was observed in 3 ream-and-run procedures (6%) and in 8 TSAs (10%). These radiographic findings were not significantly associated with patient demographic characteristics, canal-filling ratios, or clinical outcomes. CONCLUSION: When inserted with impaction autografting, a smooth, standard-length humeral stem offers a secure bone-preserving approach for humeral component fixation in shoulder arthroplasty. These results with a conventional prosthesis can serve as a basis for comparison for new component designs and fixation methods.

Clinical effectiveness and safety of the extended humeral head arthroplasty for selected patients with rotator cuff tear arthropathy.

BACKGROUND: Cuff tear arthropathy is commonly managed with a reverse total shoulder arthroplasty (RTSA). A humeral hemiarthroplasty with an extended humeral head may provide a less invasive alternative for selected patients with cuff tear arthropathy if the shoulder has preserved active elevation. Because evidence regarding this procedure is limited, we investigated its safety and efficacy in treating selected patients with cuff tear arthropathy. METHODS: We analyzed the preoperative characteristics, surgical findings, and clinical outcomes for patients selected for extended head hemiarthroplasty. RESULTS: For 42 patients with 2-year follow-up, there were no complications or revisions. The Simple Shoulder Test score improved from a median of 3.0 to 8.0 (P < .001). The median percentage of maximal possible improvement was 50% (P < .001). The percentage of patients able to perform each of the functions of the Simple Shoulder Test was significantly improved; for example, the ability to sleep comfortably increased from 19% to 71%, and the ability to place a coin on the shelf at shoulder level increased from 38% to 86% (P < .001). CONCLUSIONS: There are circumstances in which RTSA is clearly the preferred procedure for cuff tear arthropathy, including pseudoparalysis, anterosuperior escape, and glenohumeral instability; however, in shoulders with preserved active motion and stability of the humeral head provided by an intact coracoacromial arch, the extended head humeral arthroplasty can enable selected patients to realize improved comfort and function without the potential risks of RTSA. Extended humeral head hemiarthroplasty can provide a safe and effective alternative for the management of selected patients with rotator cuff tear arthropathy and preserved active motion.

Prearthroplasty glenohumeral pathoanatomy and its relationship to patient's sex, age, diagnosis, and self-assessed shoulder comfort and function.

BACKGROUND: There is great current interest in characterizing the prearthroplasty glenohumeral pathoanatomy because of its role in guiding surgical technique and its possible effects on arthroplasty outcome. METHODS: We examined 544 patients within 6 weeks before arthroplasty with the goals of characterizing the following: demographic and radiographic characteristics; relationships of the radiographic pathoanatomy to the patient's age, sex, and diagnosis; inter-relationships among glenoid type, glenoid version, and amount of decentering of the humeral head on the glenoid; and relationships of the pathoanatomy to the patient's self-assessed comfort and function. RESULTS: Male patients had a higher frequency of B2 glenoids and a lower frequency of A2 glenoids. The arthritic shoulders of men were more retroverted and had greater amounts of posterior decentering. Patients with types A1 and C glenoids were younger than those with other glenoid types. Shoulders with osteoarthritis were more likely to be type B2 and to be retroverted. Types B2 and C had the greatest degree of retroversion, whereas types B1 and B2 had the greatest amounts of posterior decentering. Shoulders with glenoid types B1 and B2 and those with more decentering did not have worse self-assessed shoulder comfort and function. CONCLUSIONS: Glenohumeral pathoanatomy was found to have previously unreported relationships to the patient's sex, age, and diagnosis. Contrary to what might have been expected, more advanced glenohumeral pathoanatomy (ie, type B glenoids, greater retroversion, greater decentering) was not associated with worse self-assessed shoulder comfort and function.

Ream and run and total shoulder: patient and shoulder characteristics in five hundred forty-four concurrent cases.

PURPOSE: Total shoulder (TSA) is commonly used to treat arthritic shoulders with intact rotator cuffs; however, some patients choose a ream and run (RnR) to avoid the potential risks and limitations of a prosthetic glenoid component. Little is known about how patients selecting each of these two procedures compare and contrast. METHODS: We analyzed the patient characteristics, shoulder characteristics, and two year clinical outcomes of 544 patients having RnR or TSA at the same institution during the same six year period. RESULTS: Patients selecting the RnR were more likely to be male (92.0% vs. 47.0%), younger (58 ± 9 vs. 67 ± 10 years), married (83.2% vs. 66.8%), from outside of our state (51.7% vs. 21.7%), commercially insured (59.1% vs. 25.2%), and to have type B2 glenoids (46.0% vs. 27.8%) as well as greater glenoid retroversion (19 ± 11 vs. 15 ± 11 degrees) (p < .001). The average two year SST score for the RnRs was 10.0 ± 2.6 vs. 9.5 ± 2.7 for the TSAs. The percent of maximum possible improvement (%MPI) for the RnRs averaged 72 ± 39% vs. 73 ± 29% for the TSAs. Patients with work-related shoulder problems had lower two year SSTs and lower %MPIs. Younger patients having TSAs did less well than older patients. Female patients having RnRs did less well than those having TSAs (p < 0.001). CONCLUSIONS: This investigation highlights important characteristics of patients selecting the RnR and the TSA for glenohumeral arthritis. Excellent outcomes can be achieved for appropriately selected patients having either procedure.

One and two-year clinical outcomes for a polyethylene glenoid with a fluted peg: one thousand two hundred seventy individual patients from eleven centers.

PURPOSE: Clinical shoulder science lacks a benchmark against which the early clinical value of new glenoid components can be compared; such a benchmark may be derived from a multicenter study of patients receiving an established, internationally used design of glenoid component. METHODS: We obtained data from 11 centers on 1270 patients having total shoulder arthroplasty using an all-polyethylene component with a fluted central peg. We analyzed individual patient outcomes at 1 and 2 years after surgery. We compared the improvement for each patient to the minimal clinically important difference (MCID) and calculated each patient's improvement as a percent of maximal possible improvement (MPI). RESULTS: The preoperative scores improved from SST 3 ± 2, ASES 37 ± 15, Constant score 36 ± 16, and Penn score 30 ± 19 to SST 10 ± 2, ASES 90 ± 12, Constant 76 ± 13, and Penn 80 ± 24 (p < 0.001 for each). A high percentage of patients improved by more than the MCID (SST 96%, ASES 98%, Constant 94%, Penn 93%) and obtained improvement of at least 30% of the MPI (SST 95%, ASES 98%, Constant 91%, Penn 87%). The clinical outcomes realized with this glenoid design were not worse for the 41% of shoulders with preoperative type B glenoids or for the 30% of shoulders with more than 15 degrees of glenoid retroversion. CONCLUSIONS: Individual patients from 11 international practices having total shoulder arthroplasty using a basic glenoid component design obtained highly significant clinical outcomes, providing a benchmark against which the early outcomes of new designs can be compared to determine whether they provide increased clinical value.

Preoperative skin cultures are predictive of Propionibacterium load in deep cultures obtained at revision shoulder arthroplasty.

BACKGROUND: Propionibacterium-specific cultures are commonly positive in revised shoulders without obvious signs of infection. To help identify patients at risk for these "stealth" presentations of positive Propionibacterium cultures, we assessed the value of a preoperative skin culture in predicting the results of deep cultures obtained at the time of revision shoulder arthroplasty in patients without clinical evidence of infection. METHODS: The study enrolled 60 patients undergoing revision for a prior shoulder arthroplasty without clinical evidence of infection. A preoperative culture of the skin surface was taken before skin preparation. At surgery, multiple (mean 5.9 ± standard deviation 1.6) deep tissue and explant cultures were harvested from the shoulder. Each culture was semiquantitatively reported as the specimen Propionibacterium value (SpPV). All SpPVs from the deep specimens from each patient were summed as the total shoulder Propionibacterium score (ShPS). The averaged ShPS was the total ShPS divided by the number of deep specimens harvested. RESULTS: A multivariate analysis demonstrated that the preoperative skin SpPV was predictive of the Propionibacterium load in the revised shoulders as indicated by the total ShPS (P = .004) and averaged ShPS (P = .003). CONCLUSIONS: In this series of patients, a preoperative culture of the unprepared skin was strongly predictive of the Propionibacterium load in revised shoulder arthroplasties without clinical evidence of infection. This result suggests that the results of skin cultures taken before revision surgery may help inform operative management with respect to the need for prosthesis exchange and extended postoperative antibiotic treatment.

The "tipping point" for 931 elective shoulder arthroplasties.

BACKGROUND: A patient with arthritis usually experiences the progression of symptoms over time. At some stage, the patient may decide that the symptoms have reached a level of severity that leads him or her to elect to proceed with joint replacement; we refer to this degree of symptom severity as the "tipping point." Our goal was to study the factors that influenced the tipping point for patients undergoing elective shoulder arthroplasty. METHODS: We analyzed the characteristics of 931 patients undergoing shoulder arthroplasty to determine the factors affecting the tipping point as characterized by the patients' comfort and function at the time they determined their symptoms had progressed to the point when this elective surgery was merited. RESULTS: The preoperative Simple Shoulder Test (SST) score for all patients averaged 3.6 ± 2.7. The average tipping points were different for the ream-and-run procedure (mean SST score, 5.0 ± 2.5), hemiarthroplasty (mean SST score, 3.1 ± 3.3), total shoulder arthroplasty (mean SST score, 3.0 ± 2.4), cuff tear arthropathy arthroplasty (mean SST score, 2.8 ± 2.5), and reverse total shoulder arthroplasty (mean SST score, 1.5 ± 1.8). A number of other factors were significantly associated with a higher tipping point: younger age, better health, male sex, commercial insurance, married, nonuse of narcotics, use of alcohol, and shoulder problem not related to work. CONCLUSIONS: Analysis of the tipping point-the patients' self-assessed comfort and function at the point they decide to undergo shoulder joint replacement-provides a means by which surgeons can understand the factors influencing the indications for these procedures.

Analysis of 4063 complications of shoulder arthroplasty reported to the US Food and Drug Administration from 2012 to 2016.

BACKGROUND: Most of the literature on shoulder arthroplasty failure comes from high-volume centers. These reports tend to exclude the experience of community orthopedic surgeons, who perform most of the shoulder joint replacements. METHODS: We analyzed the failure reports mandated by the US Food and Drug Administration for all hospitals. Each reported event from 2012 to 2016 was characterized by implant, failure mode, and year of surgery. RESULTS: For the 1673 anatomic arthroplasties, the most common failure modes were glenoid component failure (20.4%), rotator cuff/subscapularis tear (15.4%), pain/stiffness (12.9%), dislocation/instability (11.8%), infection (9%), and humeral component loosening (5.1%). For the 2390 reverse arthroplasties, the most common failure modes were dislocation/instability (32%), infection (13.8%), glenosphere-baseplate dissociation (12.2%), failed/loosened baseplate (10.4%), humeral component dissociation/tray fracture (5.5%), difficulty inserting the baseplate (4.8%), and difficulty inserting the glenosphere (4.2%). Although the percentage distribution among the different failure modes was relatively consistent over the years of this study, the percentage distribution of these failure modes differed substantially among different implant manufacturers. CONCLUSIONS: The Food and Drug Administration database reveals modes of shoulder arthroplasty failure that are not emphasized in the published literature, such as rotator cuff tear, infection, and postoperative pain/stiffness for anatomic total shoulder arthroplasty and implant dissociation and baseplate failure for reverse shoulder arthroplasty. Knowledge of these failure modes may help inform surgical technique and implant design in ways that will lower the risk of implant failure in the future.

Cystic Fibrosis Pulmonary Exacerbations Attributable to Respiratory Syncytial Virus and Influenza: A Population-Based Study.

BACKGROUND.: Characterization of the role of respiratory viral pathogens on cystic fibrosis (CF) pulmonary disease is needed. We aimed to determine the association of influenza and respiratory syncytial virus (RSV) activity with risk of pulmonary exacerbation (PEx) in persons with CF in the United States. METHODS.: We conducted a cohort study from January 2003 to March 2009 using the CF Foundation Patient Registry merged with Centers for Disease Control and Prevention respiratory virus surveillance data. The primary goal was to determine the association between regional influenza or RSV detections with risk of PEx requiring intravenous antibiotics or hospitalization. We analyzed outcomes by geographic region and week of event using multivariable regression models adjusted for demographic and clinical predictors of PEx stratified for children (<18 years) and adults (≥18 years) to calculate relative risks (RRs) of PEx. RESULTS.: There were 21022 individuals (52% male) in the CF patient cohort in 2003 comprised of 12702 children and 8320 adults. The overall incidence rate of PEx was 521.9 per 10000 person-months. In children, a 10% increase in the proportion of surveillance tests positive for influenza or RSV was significantly associated with increased PEx risk (RR, 1.02; 95% confidence interval [CI], 1.01-1.03) and (RR, 1.05; 95% CI, 1.02-1.07), respectively. In adults, surveillance tests positive for influenza (RR, 1.02; 95% CI, 1.01-1.02), but not RSV (RR, 0.99; 95% CI, .98-1.01), had a significant association with PEx risk. CONCLUSIONS.: Our large CF population-based cohort demonstrated a significant association between PEx risk and influenza activity in children and adults and with RSV activity in children.