ChatGPT-4 Performs Clinical Information Retrieval Tasks Utilizing Consistently More Trustworthy Resources Than Does Google Search for Queries Concerning the Latarjet Procedure.

PURPOSE: To assess the ability for ChatGPT-4, an automated Chatbot powered by artificial intelligence (AI), to answer common patient questions concerning the Latarjet procedure for patients with anterior shoulder instability and compare this performance to Google Search Engine. METHODS: Using previously validated methods, a Google search was first performed using the query "Latarjet." Subsequently, the top ten frequently asked questions (FAQs) and associated sources were extracted. ChatGPT-4 was then prompted to provide the top ten FAQs and answers concerning the procedure. This process was repeated to identify additional FAQs requiring discrete-numeric answers to allow for a comparison between ChatGPT-4 and Google. Discrete, numeric answers were subsequently assessed for accuracy based on the clinical judgement of two fellowship-trained sports medicine surgeons blinded to search platform. RESULTS: Mean (±standard deviation) accuracy to numeric-based answers were 2.9±0.9 for ChatGPT-4 versus 2.5±1.4 for Google (p=0.65). ChatGPT-4 derived information for answers only from academic sources, which was significantly different from Google Search Engine (p=0.003), which used only 30% academic sources and websites from individual surgeons (50%) and larger medical practices (20%). For general FAQs, 40% of FAQs were found to be identical when comparing ChatGPT-4 and Google Search Engine. In terms of sources used to answer these questions, ChatGPT-4 again used 100% academic resources, while Google Search Engine used 60% academic resources, 20% surgeon personal websites, and 20% medical practices (p=0.087). CONCLUSION: ChatGPT-4 demonstrated the ability to provide accurate and reliable information about the Latarjet procedure in response to patient queries, using multiple academic sources in all cases. This was in contrast to Google Search Engine, which more frequently used single surgeon and large medical practice websites. Despite differences in the resources accessed to perform information retrieval tasks, the clinical relevance and accuracy of information provided did not significantly differ between ChatGPT-4 and Google Search Engine.

An Analysis of Intrapitch Variation in Joint and Segment Velocities With Throwing Arm Kinetics in High School and Professional Baseball Pitchers.

BACKGROUND: Improper sequencing order of maximal joint and segment velocities has been identified as an important predictor for both throwing arm kinetics and ball velocity. PURPOSE: To investigate the intrapitcher variation of maximal segment velocities and the relationship to throwing arm kinetics and ball velocity in high school (HS) and professional (PRO) pitchers. STUDY DESIGN: Descriptive laboratory study. METHODS: HS (n = 59) and PRO (n = 338) pitchers, instructed to throw 8 to 12 fastball pitches, were evaluated with 3-dimensional motion capture (480 Hz). Maximal joint and segment velocities were calculated for each pitch, and the standard deviation of the maxima was calculated per pitcher. These standard deviations were used to classify pitchers as "low variance" or "high variance" for each segmental velocity subgroup, "overall low variance" or "overall high variance" based on cumulative segment velocity variation, or "population," with any pitcher eligible to be included in multiple subcategories. Maximal velocities and throwing arm kinetics were compared among the various subgroups. RESULTS: The HS low-variance shoulder internal rotation velocity subgroup (4949 ± 642 deg/s) had significantly lower maximal shoulder internal rotation velocity compared with HS population (5774 ± 1057 deg/s) (P < .001); similar findings were observed for PROs (5269 ± 835 vs 5824 ± 1076 deg/s; P < .001), as well as lower shoulder superior force compared with the PRO population (14.8% ± 8.8% vs 17.8% ± 8.8% body weight; P = .001). The PRO low-variance lead knee extension velocity subgroup had significantly lower maximal lead knee extension velocity (216 ± 135 vs 258 ± 125 deg/s; P = .001) and shoulder distractive force (111.5% ± 14.4% vs 115.6% ± 15.9% body weight; P = .003) compared with the PRO population. The PRO overall low-variance subgroup had significantly lower shoulder distractive force (111.8% ± 14.1% vs 119.6% ± 15.5% body weight; P = .008) and elbow anterior force (40.6% ± 5.0% vs 43.6% ± 6.2% body weight; P = .008) compared with the PRO overall high-variance subgroup. CONCLUSION: HS and PRO pitchers with low variance for joint and segment velocities achieved significantly lower maximal velocities in the subgroup of interest, while preserving ball velocity. PRO pitchers with overall low variance among multiple maximal joint and segment velocities demonstrated decreased shoulder distractive and elbow anterior force. CLINICAL RELEVANCE: PRO pitchers with low intrapitch variation in maximal joint and segment velocities may be viewed as kinetically conservative throwers. These pitchers with similarly maintained mechanics between pitches may have an increasingly regimented form that preserves kinetic forces about the throwing arm. The opposite may be true for PRO pitchers with increased variability in segmental velocities during their pitching motion, as they showed increased throwing arm kinetics including shoulder distractive and elbow anterior force compared with the overall low-variance group, theoretically increasing their risk of injury.

High Rate of Clinically Meaningful Achievement in Outcomes After Subacromial Balloon Spacer Implantation for Massive Irreparable Rotator Cuff Tears: A Systematic Review and Meta-analysis.

BACKGROUND: Subacromial balloon spacers have been introduced as a potential treatment option for patients with massive irreparable rotator cuff tears. However, it is important to comprehensively assess the clinical efficacy of this procedure in the context of an increasing amount of contemporary literature. PURPOSE: To perform a systematic review of the contemporary literature to understand the propensity for clinically meaningful improvements after subacromial balloon spacer implantation for massive irreparable rotator cuff tears. STUDY DESIGN: Systematic review and meta-analysis; Level of evidence, 4. METHODS: The PubMed, Ovid/MEDLINE, and Cochrane databases were queried in July 2022 for data pertaining to studies reporting clinically significant outcomes after subacromial balloon spacer implantation. Freeman-Tukey double arcsine transformation was used to quantify the pooled rate of clinically meaningful improvements in outcomes as evaluated using the minimal clinically important difference (MCID), Patient Acceptable Symptom State (PASS), and substantial clinical benefit (SCB). Qualitative analysis was performed when data were variably presented to avoid misleading reporting. RESULTS: There were 10 studies included, all of which reported MCID achievement. The overall pooled rate of MCID achievement for the Constant-Murley score was 83% (95% CI, 71%-93%; range, 40%-98%), with 6 of 8 studies reporting rates equal to or exceeding 85%. One study reported a 98% rate of PASS achievement for the Constant-Murley score at 3-year follow-up. The rate of MCID achievement for the American Shoulder and Elbow Surgeons (ASES) score ranged between 83% and 87.5%. The rate of PASS achievement for the ASES score was 56% at 2-year follow-up, while the rate of SCB achievement for the ASES score was 83% and 82% at 1- and 2-year follow-up, respectively. At 1-year follow-up, 74% and 78% of patients achieved the MCID for the Numeric Rating Scale and Oxford Shoulder Score, respectively. At 3 years, 69% of patients achieved the MCID for the Numeric Rating Scale and 87% achieved it for the Oxford Shoulder Score. CONCLUSION: Patients who underwent isolated subacromial balloon spacer implantation for massive irreparable rotator cuff tears demonstrated a high rate of clinically significant improvement in outcomes at short- to mid-term follow-up. A paucity of literature exists to appropriately define and evaluate the rates of achieving the PASS and SCB after subacromial balloon spacer implantation, necessitating further study.

Outcomes after débridement, antibiotics, and implant retention for prosthetic joint infection in shoulder arthroplasty.

BACKGROUND: Patients who undergo total shoulder arthroplasty usually have excellent long-term outcomes. However, a subset of patients is diagnosed with a prosthetic joint infection (PJI) requiring revision procedures and prolonged recovery. The purpose of this study was to evaluate rates of recurrent shoulder PJI in patients undergoing débridement, antibiotics, and implant retention (DAIR), single-stage revision, and 2-stage revision. We also sought to compare outcomes and complications across procedures. METHODS: Retrospective chart review was conducted for patients diagnosed with PJI after primary shoulder arthroplasty between January 2010 and August 2021. Patients were included if they underwent treatment with DAIR, single-stage revision, or 2-stage revision. Demographic information, surgical details, complications, laboratory data, postoperative antibiotic regimen, and infectious pathogen were collected. Postoperative patient-reported outcomes were collected: American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, Single Assessment Numeric Evaluation, Shoulder Activity Scale, and PROMIS Upper Extremity. Chi-square, t test, and 1-way analysis of variance were used as appropriate to evaluate each factor. RESULTS: Sixty-five patients were included in the study, 26% treated with DAIR, 9% treated with single-stage revision, and 65% treated with 2-stage revision. There were no significant differences in patient comorbidities. Patients undergoing DAIR were diagnosed significantly earlier than those undergoing single- and 2-stage revision procedures (12.6 ± 22.9 months vs. 49.6 ± 48.4 vs. 25.0 ± 26.6, P = .010). Recurrent PJI was noted in 23.1% of patients: 29.4% of DAIR patients, no single-stage patients, and 23.8% of 2-stage patients (P = .330). Patients undergoing 2-stage revision with treatment failure had a significantly higher Elixhauser Comorbidity Index (0.2 ± 3.7 vs. 3.7 ± 3.9, P = .027). There was no significant difference in patient-reported outcomes across groups. CONCLUSION: Patients undergoing treatment of shoulder PJI with DAIR did not have an increased rate of reinfection compared with single-stage and 2-stage revision procedures. Patients treated with DAIR were diagnosed with PJI significantly earlier than those undergoing single-stage and 2-stage revision procedures. There was no difference in complication rates between groups. This information adds to the body of work detailing outcomes after DAIR for shoulder PJI and provides encouraging data for use in this patient population. Future studies with a larger sample size may be conducted to further investigate specific pathogens, infection timelines, and antibiotic regimens that reduce the risk of treatment failure.

Biomechanical properties of suprapectoral biceps tenodesis with double-anchor knotless luggage tag sutures vs. subpectoral biceps tenodesis with single-anchor whipstitch suture using all-suture anchors.

Background: As the use of all-suture anchors continues to increase, limited biomechanical data on the use of these anchors in various configurations for tenodesis of the long head biceps tendon (LHBT) exists. The aim of this study was to compare the biomechanical properties of a 2-anchor luggage tag suprapectoral biceps tenodesis (Sup-BT) vs. a single-anchor whipstitch subpectoral biceps tenodesis (Sub-BT) using all-suture anchors. The hypothesis was that the Sub-BT will have a higher ultimate load to failure and less creep relative to the Sup-BT construct. Methods: Eighteen fresh frozen cadaveric humeri were used. The specimens were randomly divided into 2 groups of 9; i) The Sup-BT were performed with 2 1.8 mm knotless all-suture anchors using a luggage-tag fixation configuration, ii) The Sub-BT were performed using a single 1.9 mm all-suture anchor and a whipstitch suture configuration with a tied knot. The humeri were tested on a hydraulic MTS machine where the specimens were preloaded at 5 N for 2 minutes and then cyclically loaded from 5 to 50 N for 1000 cycles at 1 Hz while maximum displacement was recorded with a motion system and markers attached to the bone and bicep tendon. The tendon was then tensioned at a rate of 1 mm/s to obtain the ultimate load to failure. CT scans of the specimens were used to calculate the bone mineral density at the site of the anchor/bone interface and video recordings were captured during load to failure to document all modes of failure. Results: There was no significant difference in the average load to failure of the Sup-BT and Sub-BT groups (197 N ± 45 N (SD), 164 N ± 68 N (SD) respectively; P = .122) or creep under fatigue between the Sup-BT vs. Sub-BT specimens (3.1 mm, SD = 1.5 vs. 2.2 mm, SD = 0.9; P = .162). The bone mineral density was statistically different between the 2 groups (P < .001); however, there were no observed failures at the anchor/bone interface and no correlation between failure load and bone mineral density. Conclusion: The ultimate load to failure and creep between a Sup-BT with 2 knotless all-suture anchors using a luggage tag suture configuration was equivalent to a Sub-BT with 1 all-suture anchor using a whipstitched suture configuration and a tied knot. Surgeons can perform either technique confidently knowing that they are biomechanically equivalent in a cadaver model at time zero, and they offer similar strength to other fixation methods cited in the literature.

Patient-reported outcomes measurement information system depression psychometrically underperforms compared to legacy measures and is poorly associated with postoperative functional outcomes in shoulder arthroplasty patients.

Background: The purpose of this study was to investigate the associations between each mental health patient-reported outcome measure with postoperative functional outcomes following shoulder arthroplasty, and to compare psychometric properties of patient-reported outcomes measurement information system depression to the legacy (VR-12 Mental) patient-reported outcome measure. Methods: Patients who underwent primary shoulder arthroplasty from July 2018 to February 2019 were retrospectively reviewed. Patient-reported outcomes measurement information system depression and VR-12 Mental were administered preoperatively; American Shoulder and Elbow Surgeons and Single Assessment Numeric Evaluation were administered at 6-month and 1-year postoperatively. Rasch partial credit modeling analysis was used to compare psychometric properties of legacy versus patient-reported outcomes measurement information system instruments in assessing mental health. Results: Ninety-three patients who underwent total shoulder arthroplasty (n = 52), reverse total shoulder arthroplasty (n = 39), or hemiarthroplasty (n = 2) were included. Preoperative VR-12 Mental scores were moderately associated with American Shoulder and Elbow Surgeons at 6-months (coefficient: 0.52, P = 0.026) and 1-year (coefficient: 0.65, P = 0.002), while preoperative patient-reported outcomes measurement information system depression scores were not. Patient-reported outcomes measurement information system depression demonstrated significant floor effects (16%); VR-12 Mental demonstrated minimal floor and ceiling effects (1.1% for both). VR-12 Mental demonstrated broader coverage of mental outlook on Rasch modeling than patient-reported outcomes measurement information system depression and had adequate model fit after one round of reiterative item elimination. Discussion: Patient-reported outcomes measurement information system depression was poorly associated with postoperative American Shoulder and Elbow Surgeons scores, demonstrated significant floor effects, and had limited coverage of mental health on Rasch modeling with reiterative elimination. Level of Evidence: IV.

PROMIS physical function and pain perform poorly psychometrically in patients undergoing medial patellofemoral ligament reconstruction.

PURPOSE: The purpose of this study was to assess the validity, floor and ceiling effects, and dimensionality of PROMIS Physical Function (PF) and Pain compared to legacy patient reported outcome (PRO) measures in patients undergoing medial patellofemoral ligament (MPFL) reconstruction. METHODS: Patients who underwent MPFL reconstruction between 2018 to 2020 were retrospectively reviewed. Preoperatively, patients completed the IKDC, VR-12, Kujala, SF-12, KOOS JR, PROMIS PF and Pain surveys. Inter-survey convergence was assessed with Spearman correlations. Psychometric analysis included investigations of inter-survey convergent validity, intra-survey floor and ceiling effects, and Rasch analyses with person-item fit and iterative question elimination model fit testing. RESULTS: A total of 76 patients (mean age: 22.6 ± 8.4 years) who completed preoperative surveys were included (compliance: 91.7-96.2%). Preoperatively, age was significantly associated with both PROMIS PF (coefficient: - 0.291, P = 0.005) and Pain scores (coefficient: 0.294, P = 0.002). PROMIS PF had a Very Good correlation with IKDC and PROMIS Pain had a Very Good correlation with KOOS JR. Other correlations ranged from Poor to Good. No significant floor or ceiling effects were observed for any PRO. On iterative question elimination Rasch modelling, only two questions from PROMIS PF remained after 6 rounds of elimination while PROMIS Pain had no questions remaining after 3 rounds of elimination. CONCLUSION: Preoperative PROMIS PF and Pain provided only Fair to Good correlations with most legacy PROs. Although no significant floor and ceiling effects were observed, PROMIS PF and Pain did not perform well psychometrically in this population of patients undergoing MPFL reconstruction. These results suggest PROMIS questionnaires should be used with caution in this population, especially if used in isolation, when discussing clinical expectations with patients. The authors recommend continued use of legacy PROs specific to assessment of patellar instability and function that have established validity in patellar instability populations. LEVEL OF EVIDENCE: Level IV.

Republication of "Most Readmissions Following Ankle Fracture Surgery Are Unrelated to Surgical Site Issues: An Analysis of 5056 Cases".

Background: Ankle fracture surgeries are generally safe and effective procedures; however, as quality-based reimbursement models are increasingly affected by postoperative readmission, we aimed to determine the causes and risk factors for readmission following ankle fracture surgery. Methods: Ankle fracture cases were identified from the prospectively collected American College of Surgeons National Surgical Quality Improvement Program from 2013 to 2014. Demographics, comorbidities, and fracture characteristics were collected. Rates of 30-day adverse events and readmissions were determined as well as the causes for readmission. Multivariable logistic regression analyses were performed to identify risk factors associated with having any adverse events and being readmitted within 30 days of surgery. Results: There were 5056 patients included; 167 (3.3%) were open fractures. The rate of any postoperative adverse event was 5.2%. There were 116 unplanned readmissions, with a readmission rate of 2.3%. Of the 116 unplanned readmissions, 49 (42.2%) were for reasons related to the surgery or surgical site, with the most common causes being deep surgical site/hardware infections (12.9%), superficial site infections (11.2%), and wound disruption (6.9%). Most readmissions were for reasons unrelated to the surgical site (51.7%), including cardiac disorders (8.6%), pulmonary disorders (7.8%), and neurological/psychiatric disorders (6.9%). The cause of readmission was unknown for 6% of readmissions. With multivariable logistic regression, the strongest risk factors for readmission were a history of pulmonary disease (odds ratio [OR], 2.29), American Society of Anesthesiologists (ASA) class ≥3 (OR, 2.28), and open fractures (OR, 2.04) (all P < .05). Conclusion: In this cohort of 5056 ankle fracture cases, 2.3% of patients were readmitted within 30 days, with at least 51.7% of all unplanned readmissions due to causes unrelated to the surgery or surgical site. Predictors of readmission included a history of pulmonary disease, higher ASA class, and open fractures. Based on these findings, we advocate close medical follow-up with nonorthopaedic providers after discharge for high-risk patients. Level of Evidence: Level III.

Artificial intelligence for automated identification of total shoulder arthroplasty implants.

BACKGROUND: Accurate and rapid identification of implant manufacturer and model is critical in the evaluation and management of patients requiring revision total shoulder arthroplasty (TSA). Failure to correctly identify implant designs in these circumstances may lead to delay in care, unexpected intraoperative challenges, increased morbidity, and excess health care costs. Deep learning (DL) permits automated image processing and holds the potential to mitigate such challenges while improving the value of care rendered. The purpose of this study was to develop an automated DL algorithm to identify shoulder arthroplasty implants from plain radiographs. METHODS: A total of 3060 postoperative images from patients who underwent TSA between 2011 and 2021 performed by 26 fellowship-trained surgeons at 2 independent tertiary academic hospitals in the Pacific Northwest and Mid-Atlantic Northeast were included. A DL algorithm was trained using transfer learning and data augmentation to classify 22 different reverse TSA and anatomic TSA prostheses from 8 implant manufacturers. Images were split into training and testing cohorts (2448 training and 612 testing images). Optimized model performance was assessed using standardized metrics including the multiclass area under the receiver operating characteristic curve (AUROC) and compared with a reference standard of implant data from operative reports. RESULTS: The algorithm classified implants at a mean speed of 0.079 seconds (±0.002 seconds) per image. The optimized model discriminated between 8 manufacturers (22 unique implants) with AUROCs of 0.994-1.000, accuracy of 97.1%, and sensitivities between 0.80 and 1.00 on the independent testing set. In the subset of single-institution implant predictions, a DL model identified 6 specific implants with AUROCs of 0.999-1.000, accuracy of 99.4%, and sensitivity >0.97 for all implants. Saliency maps revealed key differentiating features across implant manufacturers and designs recognized by the algorithm for classification. CONCLUSION: A DL model demonstrated excellent accuracy in identifying 22 unique TSA implants from 8 manufacturers. This algorithm may provide a clinically meaningful adjunct in assisting with preoperative planning for the failed TSA and allows for scalable expansion with additional radiographic data and validation efforts.

Determining the Time Required to Achieve Clinically Significant Outcomes on the PROMIS Upper Extremity Questionnaire After Arthroscopic Rotator Cuff Repair.

Background: Clinically significant outcome (CSO) thresholds for the Patient-Reported Outcome Measurement Information System-Upper Extremity (PROMIS-UE) score have been previously defined after arthroscopic rotator cuff repair (RCR). However, the time required to achieve CSOs for the PROMIS-UE score is unknown. Purpose: To (1) determine the time required to achieve the minimal clinically important difference (MCID), substantial clinical benefit (SCB), and Patient Acceptable Symptom State (PASS) score thresholds after RCR for the PROMIS-UE questionnaire and (2) identify patient factors associated with earlier or delayed achievement of these clinical benchmarks. Study Design: Case-control study; Level of evidence, 3. Methods: A prospectively maintained institutional database was retrospectively reviewed for consecutive patients who underwent RCR between January 2018 and January 2019. Patients were included if they completed the PROMIS-UE questionnaire both preoperatively and at standardized postoperative time intervals: 5 to 7 months (6-month time point), 11 to 13 months (1-year time point), and ≥23 months (2-year time point). Kaplan-Meier survival curves with interval censoring were used to define the cumulative percentage of patients who achieved the MCID, SCB, and PASS. Patient variables associated with earlier or delayed achievement of the MCID, SCB, and PASS were determined using Weibull parametric survival regression analysis. Results: Included were 105 patients undergoing RCR (age, 57.3 ± 10.3 years; body mass index, 31.5 ± 6.1 kg/m2). By 2-year follow-up, the cumulative percentage of patients achieving the MCID, SCB, and PASS was 86.7%, 76.2%, and 74.3%, respectively. The mean time required to reach the MCID, SCB, and PASS score thresholds was 9.5 ± 3.8, 10.3 ± 4.4, and 9.8 ± 4.6 months, respectively. Factors associated with delayed achievement of CSOs included greater baseline PROMIS-UE score (MCID and SCB) and workers' compensation insurance (PASS). Greater baseline PROMIS-UE scores were associated with earlier achievement of the PASS. Conclusion: Most patients achieved CSOs for the PROMIS-UE within 12 months of RCR. Patient-specific factors found to be associated with earlier or delayed achievement of CSOs can be used to inform patient discussions on the expected timeline for recovery after RCR.

Subacromial Balloon Spacer Implantation for Massive Irreparable Rotator Cuff Tears Is Associated With Restoration of the Acromiohumeral Interval and Glenohumeral Center of Pressure: A Systematic Review and Meta-Analysis of Controlled Laboratory Studies.

BACKGROUND: Biodegradable subacromial balloon spacers (SBSs) have become increasingly used for the treatment of massive irreparable rotator cuff tears given their theorized clinical benefits; however, the relationship between biomechanical functions of the balloon spacer and clinical benefits remains unclear. PURPOSE: To perform a systematic review and meta-analysis of controlled laboratory studies investigating the use of SBSs for massive irreparable rotator cuff tears. STUDY DESIGN: Systematic review and meta-analysis; Level of evidence, 4. METHODS: PubMed, OVID/Medline, and Cochrane databases were queried in July 2022 for biomechanical data pertaining to SBS implantation in cadaveric models of irreparable rotator cuff tears. Random-effects meta-analysis of continuous outcomes using the DerSimonian-Laird method was performed to estimate pooled-treatment effect sizes between the irreparable rotator cuff tear state and the state in which an SBS was implanted. Data reported variably or in formats not amenable to analysis were presented descriptively. RESULTS: Five studies involving 44 cadaveric specimens were included. At 0° of shoulder abduction, SBS implantation resulted in a mean inferior humeral head translation of 4.80 mm (95% CI, 3.20-6.40; P < .001) relative to the irreparable rotator cuff tear state. This decreased to 4.39 mm and 4.35 mm at 30° and 60° of abduction, respectively. At 0° of abduction, implantation of an SBS was associated with a 5.01-mm (95% CI, 3.56-6.46, P < .001) anterior translation of the glenohumeral center of contact pressure relative to the irreparable tear state. This translation changed to 5.11 mm and 5.49 mm at 30° and 60° of abduction. In 2 studies, SBS implantation restored the glenohumeral contact pressure to that of the intact state and significantly reduced subacromial pressure distribution over a rotator cuff repair state. In 1 study, a high balloon fill volume (40 mL) resulted in a significant 10.3 ± 1.4-mm more anterior humeral head position relative to the intact cuff state. CONCLUSION: SBS implantation in cadaveric models of irreparable rotator cuff tears results in significant improvements in humeral head position at 0°, 30°, and 60° of shoulder abduction. Balloon spacers may also improve glenohumeral and subacromial contact pressures, although insufficient evidence currently exists to corroborate these findings. High balloon fill volumes (40 mL) may confer supraphysiologic anteroinferior translation of the humeral head.

Association Between Limited English Language Proficiency and Disparities in Length of Stay and Discharge Disposition After Total Shoulder Arthroplasty: A Retrospective Cohort Study.

Background: Limited English language proficiency in patients undergoing total shoulder arthroplasty (TSA) may make treatment more challenging. Purpose: We sought to investigate the potential association between TSA patients' use of a language interpreter and 2 outcomes: hospital length of stay (LOS) and discharge disposition. Methods: We conducted a retrospective cohort study comparing LOS and discharge disposition after TSA for patients who required interpreter services and patients who did not at a single institution in an urban setting between 2016 and 2020. Consecutive patients requiring interpreter services who underwent TSA were matched 1:1 to patients who did not require an interpreter by age, body mass index (BMI), sex, and procedure. Multivariate regression models controlling for age, BMI, sex, smoking, opioid use, white or non-white race, procedure, and diagnosis were constructed to determine associations between interpreter use, LOS, and discharge disposition. Results: Forty-one patients were included in each cohort, exceeding the minimum number required per an a priori power analysis. Mean hospital LOS was longer in the interpreter cohort than in the non-interpreter cohort (2.8 ± 2.4 vs 1.8 ± 1.0 days, respectively). Multivariate linear regression demonstrated interpreter use was the strongest predictor of LOS, with the effect estimate indicating an additional 0.88-day LOS per patient. A greater proportion of patients from the interpreter cohort were discharged to an acute/subacute rehabilitation facility than patients from the non-interpreter cohort (n = 8 [19.5%] vs n = 2 [4.9%], respectively). Patients from the interpreter cohort were 454% more likely to be discharged to acute/subacute rehabilitation facilities. Conclusions: Our retrospective analysis of patients undergoing TSA suggests that the need for interpreter services may be associated with increased LOS and discharge to a facility. More rigorous study is needed to identify the factors that influence these outcomes and to avoid disparities in hospital stay and discharge.

How accurate are positive preoperative aspiration culture results in shoulder periprosthetic joint infection? A concordance study.

BACKGROUND: The concordance between preoperative synovial fluid cultures and intraoperative tissue cultures for identifying pathogenic microorganisms in shoulder periprosthetic joint infection (PJI) remains poorly understood. The purpose of our study was to examine the diagnostic accuracy of positive synovial fluid culture results in early pathogen identification for shoulder PJI. METHODS: A total of 35 patients who met the Musculoskeletal Infection Society criteria for PJI following primary anatomic or reverse arthroplasty and the study inclusion criteria were identified retrospectively from a single institution (multiple surgeons) from January 2011 to June 2021. The inclusion criteria required a positive preoperative intra-articular synovial fluid sample within 90 days analyzed within the same institution and intraoperative tissue cultures at the time of arthrotomy. Concordance was determined when the organism(s) identified from the aspirate correlated with the intraoperative specimens. RESULTS: Overall concordance was identified in 28 of 35 patients (80%), with similar concordance for anatomic (21 of 24, 88%) and reverse (7 of 11, 64%) shoulder arthroplasties (P = .171). Culture discordance occurred in 7 of 35 patients (20%): of these, 5 (14%) had no corresponding intraoperative culture growth whereas 2 (6%) had polymicrobial intraoperative cultures. Monomicrobial Cutibacterium acnes PJI cases were the most common (24 of 35, 69%) and had an overall concordance rate of 79%. Of 5 discordant C acnes patients, 2 had polymicrobial intraoperative cultures and 3 had negative intraoperative culture results; all the patients with negative intraoperative culture results had received antibiotics between the time of aspiration and surgery. Considered separately, concordance in patients who had a positive aspirate finding for C acnes and did not receive antibiotics prior to surgery was 19 of 21 (90%), with a sensitivity of 100% (95% confidence interval, 82%-100%) and a corresponding positive predictive value of 0.91 (95% confidence interval, 58%-93%). CONCLUSION: Preoperative positive aspiration culture results demonstrated favorable sensitivity and specificity when compared with intraoperative tissue cultures in identifying pathogenic microorganisms in shoulder PJI patients. These findings are congruent with literature from hip and knee arthroplasty. Ultimately, confidence in the accuracy of positive preoperative aspiration culture results in shoulder PJI may facilitate the development of early, targeted treatment strategies while directing patient expectations and risk.

Factors associated with humeral stem revision in anatomic to reverse total shoulder arthroplasty revision.

BACKGROUND: Recent advances in implant technology have allowed for modular or platform humeral stem insertion during initial anatomic total shoulder arthroplasty (TSA). These systems allow for humeral stem retention during conversion to reverse TSA (RTSA). However, some patients still require humeral stem revision when undergoing revision to RTSA. The purpose of this study was to evaluate the association between patient-specific factors and radiographic parameters with humeral stem revision vs. retention during conversion from TSA to RTSA. METHODS: Retrospective chart review was conducted for patients who underwent a revision TSA to RTSA between January 2010 and May 2022 at a single institution. Patients were included if their prosthesis included a convertible humeral stem. Patient demographic information, surgical details, and postoperative outcomes and complications were collected. Radiographic parameters were measured by 2 graders on radiographs taken prior to the revision procedure. The need for humeral stem revision and American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) scores (preoperative and 2 years) were also noted. Statistical analysis was performed using chi-square test for categorical variables and t test for continuous variables. RESULTS: One hundred seven patients were included, with 52 undergoing humeral stem revision. Patients were revised an average of 51.0 ± 54 months after primary TSA. Younger patient age (63.6 vs. 68.5 years, P = .017) and use of a lateralized glenosphere (1.6 mm vs. 0.4 mm, P < .001) were significantly associated with need for humeral stem revision. Glenoid to humeral head cut distance (28.3 mm vs. 26.3 mm, P = .076) approached significant association with the need for humeral stem revision. All other measurements were not associated with the need for humeral stem revision. Improvement of ASES scores at 2 years' follow-up was higher in the nonrevised group (increase of 33.4 points) than the revision group (23.3), but this did not reach significance (P = .149). Estimated blood loss and surgical time were significantly higher in the stem revision group than the non-revised group (P = .048 and P < .001, respectively). CONCLUSION: Younger patients and those receiving a lateralized glenosphere were more likely to undergo humeral stem revision during conversion from TSA to RTSA. Glenoid to the humeral head cut distance should be studied further as a potential indication for humeral stem revision, as it correlates with the space available for a revision implant. This information can guide surgeons with preoperative planning for a revision arthroplasty.

The Relationship Between Maximum Shoulder Horizontal Abduction and Adduction on Peak Shoulder Kinetics in Professional Pitchers.

BACKGROUND: Repetitive horizontal shoulder abduction during pitching can cause increased contact between the posterosuperior aspect of the glenoid and the greater tuberosity of the humeral head, theoretically putting baseball pitchers at increased risk of shoulder internal impingement and other shoulder pathologies. HYPOTHESIS: Increased shoulder horizontal abduction is associated with increased shoulder anterior force, while increased horizontal adduction is associated with increased shoulder distraction force. STUDY DESIGN: Descriptive laboratory study. LEVEL OF EVIDENCE: Level 4. METHODS: A total of 339 professional baseball pitchers threw 8 to 10 fastball pitches using 3D motion capture (480 Hz). Pitchers were divided into 2 sets of quartiles based on maximum shoulder horizontal abduction and adduction. Elbow flexion, shoulder external rotation, and peak shoulder kinetics were compared between quartiles with post hoc linear regressions conducted for the entire cohort. RESULTS: At maximum shoulder horizontal abduction, there was no difference in ball velocity between quartiles (P = 0.76). For every 10º increase in maximum shoulder horizontal abduction, shoulder anterior force decreased by 2.2% body weight (BW) (P < 0.01, B = -0.22, ß = -0.38), shoulder adduction torque decreased by 0.5%BW × body height (BH) (P < 0.01, B = -0.05, ß = -0.19), and shoulder horizontal adduction torque decreased by 0.4%BW × BH (P < 0.01, B = -0.04, ß = -0.48). For every 10º increase in maximum shoulder horizontal adduction, shoulder anterior force increased by 2%BW and ball velocity decreased by 1.2 m/s (2.7 MPH). CONCLUSION: Professional pitchers with the least amount of maximum horizontal adduction had faster ball velocity and decreased shoulder anterior force. Pitchers with greater maximum shoulder horizontal abduction had decreased shoulder anterior force, shoulder adduction torque, and shoulder horizontal adduction torque. To maximize ball velocity as a performance metric while minimizing shoulder anterior force, pitchers can consider decreasing maximum shoulder adduction angles at later stages of the pitch. CLINICAL RELEVANCE: Identifying risk factors for increased throwing shoulder kinetics (ie, shoulder anterior force, shoulder adduction torque) has potential implications in injury prevention. Specifically, mitigating shoulder anterior forces may be beneficial in reducing risk of injury.

Shoulder arthroplasty device clearance: an ancestral network analysis.

BACKGROUND: The US Food and Drug Administration (FDA) oversees medical device regulation and oversight in the United States, and the majority of shoulder arthroplasty devices are cleared via the 510(k) pathway, in which a device demonstrates "substantial equivalence" to a previously cleared predicate. The purpose of this study was to determine an interconnected ancestral network of shoulder arthroplasty devices and determine equivalency ties to devices subsequently recalled by the FDA for design-related issues. METHODS: The FDA 510(k) database was used to identify all legally marketed shoulder arthroplasty devices from May 28, 1976, to July 1, 2021. Direct predicate information obtained via clearance summary documents associated with each device was used to generate an ancestral genealogy network for all shoulder arthroplasty devices cleared between July 1, 2020, and July 1, 2021. FDA design recalls were analyzed, and the number of descendant devices was calculated for each recalled device. RESULTS: An evaluation of all 476 510(k) premarket notification pathway-cleared shoulder devices since 1976 identified 0-313 descendant devices for each. Eighty of these devices (16.8%) have since been recalled, of which 10 recalls were directly related to implant design issues. Furthermore, among 29 of the most recently cleared devices (July 1, 2020-July 1, 2021), 16 (55.2%) claim predicates devices that have subsequently been withdrawn from the market because of design-related failures. CONCLUSIONS: Shoulder arthroplasty devices are linked together via an interconnected FDA 510(k) equivalency approval network dating back to 1976 despite substantive changes in material specifications and device design, many of which have since been recalled. Many of the cleared modern devices claim predicates based on subsequently recalled prostheses.

Pathogenesis, Evaluation, and Management of Osteolysis After Total Shoulder Arthroplasty.

Radiographic osteolysis after total shoulder arthroplasty (TSA) remains a challenging clinical entity, as it may not initially manifest clinically apparent symptoms but can lead to clinically important complications, such as aseptic loosening. A thorough consideration of medical history and physical examination is essential to rule out other causes of symptomatic TSA-namely, periprosthetic joint infection-as symptoms often progress to vague pain or discomfort due to subtle component loosening. Once confirmed, nonoperative treatment of osteolysis should first be pursued given the potential to avoid surgery-associated risks. If needed, the current surgical options include glenoid polyethylene revision and conversion to reverse shoulder arthroplasty. The current article provides a comprehensive review of the evaluation and management of osteolysis after TSA through an evidence-based discussion of current concepts.

The influence of shoulder abduction and external rotation on throwing arm kinetics in professional baseball pitchers.

Background: The relationships between shoulder abduction and external rotation with peak kinetic values at the shoulder and elbow in professional baseball pitchers are not well established. Methods: Professional pitchers (n = 322) threw 8-12 fastballs under 3D motion analysis (480 Hz). Pitchers were stratified into quartiles by shoulder abduction and external rotation at distinct timepoints. Regression analyses were performed to quantify associations between shoulder position and kinetics. Results: Shoulder abduction remained relatively consistent throughout the pitch (foot contact-ball release: 85.5 ± 11.1-90.7 ± 8.4°); shoulder external rotation increased dramatically (foot contact-ball release: 30.8 ± 24.6-165.2 ± 9.7°). For every 10° increase in maximum shoulder rotation, shoulder superior force increased by 2.3% body weight (p < 0.01), shoulder distraction force increased by 5.9% body weight (p < 0.01), and ball velocity increased by 0.60 m/s (p < 0.01). Shoulder abduction was significantly associated with shoulder superior force at all timepoints but not with ball velocity (p > 0.05). For every 10° increase in shoulder abduction at ball release, shoulder superior force increased by 3.7% body weight (p < 0.01) and shoulder distraction force increased by 11.7% body weight (p < 0.01). Conclusion: Increased shoulder abduction at ball release and increased maximum shoulder external rotation were associated with greater superior and distraction forces in the shoulder. Pitchers can consider decreasing shoulder abduction at later stages of the pitch to around 80° in order to minimize shoulder superior force, with no impact on ball velocity.

Tribocorrosion is common but mild in modular humeral components in shoulder arthroplasty: an implant retrieval analysis.

Background: Wear and corrosion at the junctions of modular implants are increasingly recognized issues in the design of hip and knee arthroplasty prostheses, yet less is known about their significance in shoulder arthroplasty. Methods: A query of paired total shoulder implant specimens (eg, humeral head and stem components from the same patient) was performed using an institutional implant retrieval registry. Implants were examined under a stereomicroscope and evaluated for evidence of fretting and corrosion using the modified Goldberg scoring system. Available electronic medical records of included specimens were reviewed to report relevant clinical characteristics and identify potential associations with the presence of tribocorrosion. Results: Eighty-three paired total shoulder implant specimens, explanted at a single institution between 2013 and 2020, were analyzed. Corrosion was identified in 52% (43/83) of humeral head components and 40% (33/83) of humeral stem components. Fretting was identified in 29% (24/83) of humeral head components and 28% (23/83) of humeral stem components. Of the 56 paired implants for which clinical data were available, the duration of implantation (DOI) was less than 2 years in 29% of paired implants and greater than 5 years in 36% of implants. The presence of corrosion or fretting was not associated with DOI, a male humeral head taper, or periprosthetic infection as the indication for revision. Conclusion: Mild tribocorrosion was present in more than half of the retrieved humeral implant specimens. However, trunnionosis did not manifest as a clinical cause of revision surgery in our study.

Biomechanical analysis of anterior stability after 15% glenoid bone loss: comparison of Bankart repair, dynamic anterior stabilization, dynamic anterior stabilization with Bankart repair, and Latarjet.

BACKGROUND: Dynamic anterior shoulder stabilization (DAS) with Bankart repair is a recently described stabilization technique thought to be more robust than an isolated Bankart repair while avoiding many coracoid transfer-related complications and technical demands. DAS involves transfer of the long head biceps through a subscapularis split to the anterior glenoid to create a sling effect. We hypothesize that DAS with Bankart repair will restore anterior stability in a human-cadaveric model with subcritical (15%) glenoid bone loss. METHODS: Eight cadaveric shoulders were tested using an established shoulder simulator to record glenohumeral translations with an accuracy of ±0.2 mm. Shoulders were tested in 5 states-intact soft tissues, Bankart defect with 15% bone loss, isolated Bankart repair, DAS with Bankart repair, isolated DAS, and Latarjet. A 45 N anterior force was applied through the pectoralis major tendon, and translation of the humeral head was recorded and compared with repeated measures analysis of variance. RESULTS: The anterior translation in the intact (native) glenoid was 4.7 mm at neutral position and 4.6 mm at 45° external rotation. Anterior translation significantly increased after introducing a Bankart defect with 15% glenoid bone loss to 9.1 mm (neutral, P = .002) and 9.5 mm (45° external rotation, P < .001). All repair conditions showed a significant decrease in anterior translation relative to Bankart defect. DAS with Bankart repair decreased anterior translation compared with the Bankart defect: 2.7 mm (neutral, P < .001) and 2.1 mm (45° external rotation, P < .001). DAS with Bankart repair significantly decreased anterior translation compared with the isolated Bankart repair (2.7 mm vs. 4.7 mm, P = .023) and the isolated DAS (2.7 mm vs. 4.3 mm, P = .041) in neutral position. The Latarjet procedure resulted in the greatest reduction in anterior translation compared with the Bankart defect: 1.2 mm (neutral, P < .001) and 1.9 mm (45° external rotation, P < .001). CONCLUSIONS: DAS with Bankart repair is a viable alternative to restore anterior glenohumeral stability with a 15% glenoid defect at a greater degree than either DAS or Bankart repair alone. The Latarjet procedure was the most effective in reducing anterior translation but restrained the anterior translation significantly more than the native glenoid.