Publication rates of abstracts presented at American Shoulder and Elbow Surgeons annual open and closed conferences: 2015-2019.

Background: The annual meetings hosted by the American Shoulder and Elbow Surgeons (ASES) present the latest prepublication literature in shoulder and elbow surgery, facilitating early dissemination of novel findings that impact clinical decision-making. Evaluating the publication rate of presented abstracts at ASES conferences becomes crucial in assessing the quality of research showcased, as these presentations often precede the peer-review process. Methods: The ASES conference programs from 2015-2019 were reviewed to identify presented abstracts. For each abstract, the title, author(s), conference year, and meeting type (open vs. closed) were recorded. The names of the author(s) of each abstract were searched in the PubMed and Google Scholar databases to determine if there was an associated published manuscript. For each identified manuscript, the title, author(s), date of publication, publishing journal, impact factor of the publishing journal, level of evidence, and number of citations were recorded. Results: A total of 316 abstracts were presented as podium lectures at ASES open and closed meetings between 2015 and 2019. Within 3 years of presentation, 240 (75.9%) of the presented abstracts resulted in publication. There was an increase in the proportion of abstracts resulting in publication within 3 years of the presentation from 2015-2019 (R = 0.8733, P = .053). Overall, the proportion of presented abstracts that went on to publication in peer-reviewed journals also increased (R = 0.8907, P = .043). Manuscripts of abstracts presented at open meetings had a shorter time to publication (8.78 vs. 11.82 months; P = .0160) and were cited more often (40.89 vs. 30.11, P = .0099) than those presented at closed meetings. Conclusion: There has been an increase in the publication rate of abstracts presented at ASES annual meetings in the study period. Published manuscripts of abstracts presented at ASES open conferences were published faster, and were cited more often, than closed conferences. ASES conferences allow for the presentation of high-quality prepublication literature in shoulder and elbow surgery.

Do ChatGPT and Google differ in answers to commonly asked patient questions regarding total shoulder and total elbow arthroplasty?

BACKGROUND: Artificial intelligence (AI) and large language models (LLMs) offer a new potential resource for patient education. The answers by Chat Generative Pre-Trained Transformer (ChatGPT), a LLM AI text bot, to frequently asked questions (FAQs) were compared to answers provided by a contemporary Google search to determine the reliability of information provided by these sources for patient education in upper extremity arthroplasty. METHODS: "Total shoulder arthroplasty" (TSA) and "total elbow arthroplasty" (TEA) were entered into Google Search and ChatGPT 3.0 to determine the ten most FAQs. On Google, the FAQs were obtained through the "people also ask" section, while ChatGPT was asked to provide the ten most FAQs. Each question, answer, and reference(s) cited were recorded. A modified version of the Rothwell system was used to categorize questions into 10 subtopics: special activities, timeline of recovery, restrictions, technical details, cost, indications/management, risks and complications, pain, longevity, and evaluation of surgery. Each reference was categorized into the following groups: commercial, academic, medical practice, single surgeon personal, or social media. Questions for TSA and TEA were combined for analysis and compared between Google and ChatGPT with a 2 sample Z-test for proportions. RESULTS: Overall, most questions were related to procedural indications or management (17.5%). There were no significant differences between Google and ChatGPT between question categories. The majority of references were from academic websites (65%). ChatGPT produced a greater number of academic references compared to Google (80% vs. 50%; P = .047), while Google more commonly provided medical practice references (25% vs. 0%; P = .017). CONCLUSION: In conjunction with patient-physician discussions, AI LLMs may provide a reliable resource for patients. By providing information based on academic references, these tools have the potential to improve health literacy and improved shared decision making for patients searching for information about TSA and TEA. CLINICAL SIGNIFICANCE: With the rising prevalence of AI programs, it is essential to understand how these applications affect patient education in medicine.

Predictive factors influencing internal rotation following reverse total shoulder arthroplasty.

BACKGROUND: Reverse total shoulder arthroplasty (RTSA) is increasingly used as a treatment modality for various pathologies. The purpose of this review is to identify preoperative risk factors associated with loss of internal rotation (IR) after RTSA. METHODS: A systematic review was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Ovid MEDLINE, Ovid Embase, and Scopus were queried. The inclusion criteria were as follows: articles in English language, minimum 1-year follow-up postoperatively, study published after 2012, a minimum of 10 patients in a series, RTSA surgery for any indication, and explicitly reported IR. The exclusion criteria were as follows: articles whose full text was unavailable or that were unable to be translated to English language, a follow-up of less than 1 year, case reports or series of less than 10 cases, review articles, studies in which tendon transfers were performed at the time of surgery, procedures that were not RTSA, and studies in which the range of motion in IR was not reported. RESULTS: The search yielded 3792 titles, and 1497 duplicate records were removed before screening. Ultimately, 16 studies met the inclusion criteria with a total of 5124 patients who underwent RTSA. Three studies found that poor preoperative functional IR served as a significant risk factor for poor postoperative IR. Eight studies addressed the impact of subscapularis, with 4 reporting no difference in IR based on subscapularis repair and 4 reporting significant improvements with subscapularis repair. Among studies with sufficient power, BMI was found to be inversely correlated with degree of IR after RTSA. Preoperative opioid use was found to negatively affect IR. Other studies showed that glenoid retroversion, component lateralization, and individualized component positioning affected postoperative IR. CONCLUSIONS: This study found that preoperative IR, individualized implant version, preoperative opioid use, increased body mass index and increased glenoid lateralization were all found to have a significant impact on IR after RTSA. Studies that analyzed the impact of subscapularis repair reported conflicting results.

Arthroscopic Removal of Extra-Articular Foreign Bodies From the Shoulder: Inside-Out Technique.

Arthroscopic shoulder surgery can be performed for retrieval of bullets and retained metallic fragments in the glenohumeral and subacromial spaces. Previous case reports and case series have demonstrated the effectiveness of an arthroscopic approach over an open procedure, as it is less invasive, allows for improved inspection and documentation of the joint surfaces and periarticular structures, and potentially leads to a faster recovery. An arthroscopic approach for extracting foreign bodies from both the quadrilateral space and the posterior extra-articular space by first accessing the glenohumeral space has yet to be described. This inside-out technique may afford surgeons the potential for improved visualization and less morbidity compared with a traditional open posterior approach. We report a technique for an arthroscopic inside-out approach for removal of extra-articular foreign bodies retained in either the quadrilateral space or the posterior extra-articular space.

Radius of curvature of the radial head matches the capitellum: a magnetic resonance imaging analysis.

Background: The purpose of this study is to utilize elbow magnetic resonance imaging (MRI) to compare the radius of curvature (ROC) of the radial head peripheral cartilaginous rim and the cartilage contour of the capitellum to evaluate if the radial head could be a suitable osteochondral autograft for capitellar pathology. Methods: All patients who underwent an MRI of the elbow over a three-year period were reviewed. Patients with the following diagnoses were excluded: osteochondritis dissecans, osteomyelitis, tumor, and osteoarthritis. The radius of curvature of the radial head (RhROC) was measured on the axial oblique MRI sequence. The radius of curvature of the capitellum (CapROC) was measured on sagittal oblique MRI sequences, the width of the articular surface of the capitellum on coronal MRI sequences and the radial head height (RhH) and capitellar vertical height on sagittal oblique sequences. All measurements were obtained at the midpoint of the radiocapitellar joint. Spearman's coefficient was used to assess the correlation between ROC measurements. Results: Eighty-three patients were included with a mean age of 43 +/- 17 years (57 males and 26 females, 51 right and 32 left elbows). The median RhROC and CapROC measurements were 12.3 mm (interquartile range [IQR] 1.6) and 11.9 mm (IQR 1.7), respectively. The median difference was 0.3 mm (IQR = 0.6; CI 95% = [0.24, 0.46]; P < .001). A strong positive correlation was found between RhROC and CapROC (ρ = 0.89; r2 = 0.819; P < .001). Ninety-four percent (78/83) of patients had a median difference between the RhROC and CapROC of less than or equal to 1 mm, and 63% (52/83) were within 0.5 mm. The inter-rater and intra-rater reliability for RhROC and CapROC was good, intraclass correlation coefficient (ICC) = 0.89, ICC = 0.87, and ICC = 0.96, ICC = 0.97, respectively. RhH was 10.6 ± 1.3 mm, and the width of the articular surface of the capitellum was found to be 13.8 ± 1.6 mm. Conclusion: The ROC of the convex peripheral cartilaginous rim of the radial head is similar to the ROC of the capitellum. In addition, the RhH was approximately 78% of the capitellar articular width. Based on this imaging analysis, the radial head could prove to be a robust local osteochondral autograft with a similar cartilage contour in the reconstruction of the capitellum in complex intra-articular distal humerus fractures with associated radial head fractures and in the setting of "kissing lesions" of the radiocapitellar joint. Furthermore, an osteochondral plug harvested from the "safe zone" of the peripheral cartilaginous rim of the radial head could be utilized to treat isolated osteochondral lesions of the capitellum.

Short-term outcomes after primary reverse total shoulder arthroplasty in patients with cervical spine pathology or previous cervical spine surgery compared to those without.

BACKGROUND: Cervical spine (c-spine) and shoulder pathology have been known to cause similar symptoms and often co-exist, making an accurate diagnosis difficult, especially in an elderly population. Reverse total shoulder arthroplasty (rTSA) has been shown to decrease pain and improve quality of life when shoulder pathology is the source of pain and disability. The purpose of this study was to identify the prevalence of c-spine pathology in a cohort of patients who underwent rTSA and to compare postoperative outcome scores to a cohort without c-spine pathology. METHODS: A retrospective review was performed utilizing a single institution's operative records of primary rTSAs. Radiology reports, imaging, and operative reports were reviewed, and presence of any c-spine pathology or previous surgery were recorded. Additionally, postoperative outcome scores (American Shoulder and Elbow Surgeons [ASES], Constant Score, University of California, Los Angeles [UCLA], and Simple Shoulder Test [SST]) were evaluated at >2 years post-rTSA. RESULTS: A total of 438 primary rTSA cases were evaluated. Of these, 143 (32.6%) had documentation of prior c-spine pathology and/or history of previous c-spine surgery. After applying further exclusion criteria, a total of 50 patients with c-spine pathology and 108 patients without c-spine pathology were found to have complete medical records and postoperative outcome scores to allow comparison between groups. Patients without c-spine pathology were found to have statistically higher postoperative UCLA, ASES, and SST scores when compared to patients with c-spine pathology. Patients without c-spine pathology also demonstrated a significant improvement in the difference between their postoperative and preoperative UCLA and ASES scores. CONCLUSION: This study demonstrated a high prevalence of c-spine pathology (32.6%) in a cohort of patients who underwent primary rTSA. Additionally, short-term outcome scores of patients undergoing rTSA with concomitant c-spine pathology are significantly lower than those of patients without a history of c-spine pathology.

Risk factors of instability following reverse total shoulder arthroplasty in patients with no history of shoulder surgery.

Introduction: As its indications expand, reverse total shoulder arthroplasty (rTSA) utilization continues to increase. Though relatively uncommon, instability following rTSA can be associated with significant morbidity and need for subsequent revision and treatment. This case control study aims to characterize factors leading to instability after rTSA, especially in those with no previous shoulder surgery. Methods: 194 rTSAs performed within the study period with appropriate operative indications and follow-up were included. Risk factors used in analysis included age, gender, BMI, ASA class, Charlson comorbidity index (CCI), glenosphere, tray, and liner size. Data was analyzed using a hierarchical binary logistical regression to create a predictive model for instability. Results: Seven patients sustained a post-operative dislocation. Mean time to dislocation was 60.4 weeks. Five required open reduction with placement of either a larger humeral tray or polyethylene spacer. One required open reduction with osteophyte removal, and one was converted to a resection arthroplasty. Dislocators were more likely to have a larger BMI (p = 0.002), higher ASA classification (p = 0.09), and larger liner size (p = 0.01). Conclusion: This study demonstrates a large series of patients successfully treated with rTSA. Dislocations were an uncommon complication, but were clearly associated with higher patient BMI, ASA classification, and increased liner size.

Outcomes and complications of primary reverse shoulder arthroplasty with minimum of 2 years' follow-up: a systematic review and meta-analysis.

BACKGROUND: Primary reverse shoulder arthroplasty (rTSA) is an effective treatment option for reducing pain and improving function for patients with rotator cuff tear arthropathy, irreparable rotator cuff tears, glenoid deformity, and other challenging clinical scenarios, including fracture sequelae and revision shoulder arthroplasty. There has been a wide range of reported outcomes and postoperative complication rates reported in the literature. The purpose of this systematic review and meta-analysis is to provide an updated review of the clinical outcomes and complication rates following primary rTSA. METHODS: A systematic review and meta-analysis was performed to evaluate outcomes and complications following primary rTSA according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Demographics, range of motion, patient-reported outcome measures (American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form [ASES] and Constant scores), number of complications, and revisions were extracted, recorded, and analyzed from the included articles. RESULTS: Of the 1415 studies screened, 52 studies met the inclusion criteria comprising a total of 5824 shoulders. The mean age at the time of surgery was 72 years (range: 34-93), and the mean follow-up was 3.9 years (range: 2-16). Patients demonstrated a mean improvement of 56° in active flexion, 50° in active abduction, and 14° in active external rotation. Regarding functional outcome scores, rTSA patients demonstrated a mean clinically significant improvement of 37 in Constant score (minimal clinically important difference [MCID] = 5.7) and ASES score (42.0; MCID = 13.6). The overall complication rate for rTSA was 9.4% and revision rate of 2.6%. Complications were further subdivided into major medical complications (0.07%), shoulder- or surgical-related complications (5.3%), and infections (1.2%). The most frequently reported shoulder- or surgical-related complications were scapular notching (14.4%), periprosthetic fracture (0.8%), glenoid loosening (0.7%), and prosthetic dislocation (0.7%). DISCUSSION: Primary rTSA is a safe and reliable procedure with low complication, revision, infection, and scapular notching rates. Additionally, patients demonstrated clinically significant improvements in both range of motion and clinical outcome scores.

Reverse total shoulder arthroplasty in patients 80 years and older: a national database analysis of complications and mortality.

BACKGROUND: Although reverse total shoulder arthroplasty (RSA) is considered a safe surgical option in elderly patients, large-scale analyses of complications and mortality after RSA in patients 80 years and older are scarce. The goals of the current study were to identify revision, complication, and early mortality rates after RSA in patients 80 years and older and compare these to younger patients. METHODS: The PearlDiver Database, which contains services rendered to Medicare, Medicaid, and commercial insurance patients, was queried for patients undergoing RSA using International Classification of Diseases, Ninth/Tenth Revision (ICD-9/ICD-10) procedure codes. Patients were separated into 2 groups based on their age: 80 years and older and <80 years of age. The incidence of revision arthroplasty, medical, and surgical complications after RSA were extracted. Multivariate regression was used to compare revision arthroplasty and complication rates between groups. Statistical significance was set at P <.05. RESULTS: A total of 29,430 cases of RSA were included, with 486 cases in patients 80 years and older (median age, 80 years; age range, 2 years). Patients 80 years and older had 1- and 2-year revision rates of 3.9% and 5.1%, compared with the younger cohort at 3.0% and 3.1%, respectively. In patients 80 years and older, there were higher rates of deep venous thrombosis (DVT) (odds ratio [OR] 2.87, 95% CI 1.5-4.97), urinary tract infection (OR 1.42, 95% CI 1.01-1.94), acute renal failure (OR 2.18, 95% CI 1.44-3.17), and pneumonia (OR 1.75, 95% CI 1.09-2.68) within 90 days postoperatively. Ninety-day surgical complications were similar between the cohorts; however, younger patients experienced higher rates of dislocation, stiffness, periprosthetic fracture, and implant complications 1 year postoperatively. Patients 80 years and older had a significantly higher 90-day mortality rate at 2.7% compared with 1.5% in younger patients (P = .002). CONCLUSIONS: RSA is a generally safe procedure even in patients 80 years and older, with low complication and revision rates. Patients 80 years and older had higher early mortality and medical complication rates, including DVT, renal failure, and pneumonia than patients <80 years of age. However, patients 80 years and older had lower rates of dislocation, periprosthetic fracture, and implant-related complication at 1 year postoperatively.

Muscle Tendon Transfers Around the Shoulder: Diagnosis, Treatment, Surgical Techniques, and Outcomes.

➤: Muscle tendon transfers (MTTs) are effective surgical procedures for reducing pain and for improving active shoulder range of motion and patient-reported outcomes for a wide range of pathologies, including serratus anterior and trapezius muscle palsy, irreparable subscapularis tears, irreparable posterosuperior rotator cuff tears, irreparable posterior rotator cuff tears in the setting of reverse shoulder arthroplasty, and symptomatic complete deltoid deficiency. ➤: The principles of MTT include ensuring that the transferred muscle is expendable, the muscle tendon unit has similar excursion, the line of pull of the transferred tendon and of the recipient muscle are similar in terms of biomechanical force, and the transferred muscle should replace at least 1 grade of strength of the deficient recipient muscle. ➤: When MTT procedures are considered, patients must have exhausted all nonoperative management, have preserved passive range of motion, and have an understanding of the postoperative expectations and potential complications. ➤: For patients with scapulothoracic abnormal motion (STAM) due to long thoracic nerve palsy, the indirect or direct pectoralis major tendon transfer is an effective procedure for reducing pain and improving active forward elevation. For patients with STAM due to spinal accessory nerve palsy, the Eden-Lange or the triple tendon transfer procedures reduce pain and improve active forward elevation and abduction as well as patient-reported clinical outcomes. ➤: Both pectoralis major and latissimus dorsi transfer procedures for isolated irreparable subscapularis deficiency without anterosuperior humeral head escape result in improvement with respect to pain, patient-reported outcomes, and forward elevation, with the pectoralis major tendon transfer demonstrating durable long-term outcomes. ➤: The latissimus dorsi or lower trapezius tendon transfer procedures for irreparable posterosuperior rotator cuff tears reliably improve patient-reported outcomes, forward elevation, abduction, and external rotation range of motion. Additionally, latissimus dorsi transfer with or without teres major transfer can be used to restore active external rotation, both in the native shoulder and in the setting of reverse shoulder arthroplasty. ➤: The complications of MTTs include infection, hematoma, and failure of tendon transfer healing; therefore, it is recommended that these complex procedures be performed by shoulder surgeons with appropriate training.

Opioid requirements in primary versus revision reverse shoulder arthroplasty.

PURPOSE: The purpose of this study is to evaluate the inpatient pain medication use of patients who had a revision shoulder arthroplasty procedure performed and compare them to a cohort of patients who had a primary reverse total shoulder arthroplasty (rTSA) performed to determine whether revision shoulder arthroplasty requires more pain medication.. METHODS: A retrospective review was performed on patients undergoing revision arthroplasty (n = 75) and primary rTSA (n = 340). Inpatient medication records were reviewed to tabulate the visual analog pain (VAS) all narcotic medication use, and total morphine equivalent units (MEUs) were calculated for the duration of the inpatient stay. RESULTS: There was no significant difference between groups regarding age, sex, body mass index, Charlson Comorbidity Index, American Society of Anesthesiologists score, preoperative narcotic pain medication use, tobacco use, postoperative VAS scores or hospital length of stay. There were no predictors of total postoperative MEUs identified. Overall, patients in the revision arthroplasty group received significantly less total MEUs than those in the primary rTSA group, 134.96 MEUs vs. 69.79 MEUs, respectively (p < .0005). CONCLUSION: The perceived notion that revision shoulder arthroplasty is more painful may cause providers to be more inclined to increase narcotic use, or use more invasive pain control techniques. Based on these data, we found that revision shoulder arthroplasty did not require an increased opioid requirement, longer length of stay or increase VAS, suggesting that these patients can often be managed similarly to primary rTSA.

Primary Medial Patellofemoral Ligament Reconstruction in Military Servicemembers: Can We Reliably Restore Preinjury Function and Stability?

BACKGROUND: Medial patellofemoral ligament (MPFL) reconstruction for patellar instability is a commonly performed procedure with a reported high rate of return to preinjury activity. However, no previous study has assessed the functional outcomes of military servicemembers undergoing MPFL reconstruction. HYPOTHESIS: Primary MPFL reconstruction confers patellar stability, but with limited return to preinjury function and ability to maintain unrestricted military active duty status. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Using the Management Analysis and Reporting Tool database, we conducted a retrospective review of active duty servicemembers throughout the US Department of Defense Health System who underwent primary MPFL reconstruction between 2012 and 2015. Demographic variables were recorded as well as ability to return to impact activities-defined as running, jumping, rucking with a load >40 pounds (18 kg), and returning to airborne operations-and to remain on active duty status. The rates of recurrent instability and the need for subsequent surgeries were identified and assessed for statistical significance using uni- and multivariate analyses. Patients were evaluated for a minimum of 2 years postoperatively. RESULTS: Of the 213 patients who underwent primary MPFL reconstruction, including 34 with concomitant tibial tubercle osteotomy, 19 (8.9%) patients developed recurrent instability. The presence of bilateral patellar instability was associated with higher recurrence rate. Patients with bilateral instability comprised 47.3% of those with recurrence but only 24.9% of patients without recurrence (P = .019). Impact activity restrictions were present in 57.6% of patients (n = 121), with 86 patients (52.1%) undergoing medical separation from the military. Patients who were prescribed activity restriction before surgery were significantly more likely to have postoperative activity restrictions (64.5%; P = .019), and junior enlisted servicemembers were more likely to be medically separated from service postoperatively than higher ranking senior enlisted members or officers. CONCLUSION: Only 42.4% of US military servicemembers undergoing primary MPFL reconstruction were able to return to unrestricted impact activity after surgery. Bilateral instability negatively affected return to impact activities. Military servicemembers, particularly junior enlisted members, should be counseled on this poor prognosis for a full return to unrestricted activity postoperatively.

Utility of Allograft Talus as a Source for Grafting of Concurrent Humeral and Glenoid Defects Associated With Anterior Glenohumeral Instability: An Anthropometric Analysis.

PURPOSE: To compare morphologic data of the talus using magnetic resonance images with previously reported values of the humeral head and the glenoid as a potential graft source for both the humeral head as well as glenoid reconstruction in the setting of concomitant glenoid and humeral head defects. METHODS: All magnetic resonance images of the ankle were reviewed for assessment of the morphology and variation of the talus among individuals. Patients with post-traumatic, osteoarthritic, or surgical changes to the distal tibia about the mid- or hind- foot, or patients with incomplete medical records were excluded. Radiographic parameters that were measured included the maximum vertical height (MVH), the height to the talar neck, the radius of curvature (ROC) of the talar dome, ROC of the subtalar joint, and the maximum medial-to-lateral width of the talar dome. Demographic data also were collected on each individual. Statistical analysis was performed via a linear regression model with backwards elimination to determine which demographic data correlated most strongly with talar anthropometric values. RESULTS: A total of 82 study patients met inclusion criteria (59 male, 23 female; mean age 40.91 ± 14.69 years). Sex was found have a positive correlation of the following talar dimensions: MVH (P = .039), talar dome ROC (P < .001), and subtalar joint ROC (p = 0.001). Height was the most positive correlation for medial-to-lateral width (P < .001), height to the talar neck (P = .004), and also correlate for MVH (P = .004). Body mass index was found to have multicollinearity and was therefore not used as a variable. CONCLUSIONS: Allograft talus appears to be a viable graft, as demonstrated in this anthropometric study for both reconstruction of the glenoid and humeral head when cases of bipolar glenohumeral bone loss are present. CLINICAL RELEVANCE: This study aims to further evaluate potential allograft donor sites for bipolar lesions.

Comparison of complication types and rates associated with anatomic and reverse total shoulder arthroplasty.

BACKGROUND: Complications after anatomic (aTSA) and reverse (rTSA) total shoulder arthroplasty can be devastating to a patient's quality of life and require revisions that are costly to both the patient and the health care system. The purpose of this study is to determine the types, incidence, and timing of complications following aTSA and rTSA using an international database of patients who received a single-platform total shoulder arthroplasty system, in order to quantify the types of failure modes and the differences that occur between aTSA and rTSA. METHODS: A total of 2224 aTSA (male-female, 1090:1134) and 4158 rTSA (male-female, 1478:2680) patients were enrolled in an international database of primary shoulder arthroplasty performed by 40 different surgeons in the United States and Europe. Adverse events and revisions reported for these 6382 patients were analyzed to identify the most common failure modes associated for both aTSA and rTSA. RESULTS: For the 2224 aTSA patients, 239 adverse events were reported for a complication rate of 10.7% and 124 revisions for a revision rate of 5.6%. The top 3 complications for aTSA were rotator cuff tear/subscapularis failure (n = 69; complication rate = 3.1%, revision rate = 1.9%), aseptic glenoid loosening (n = 55; complication rate = 2.5%, revision rate = 1.9%), and infection (n = 28; complication rate = 1.3%, revision rate = 0.8%). For the 4158 rTSA patients, 372 adverse events were reported for a complication rate of 8.9% and 104 revisions for a revision rate of 2.5%. The top 3 complications for rTSA were acromial/scapular fracture/pain (n = 102; complication rate = 2.5%, revision rate = 0.0%), instability (n = 60; complication rate = 1.4%, revision rate = 1.0%), and pain (n = 49; complication rate = 1.2%, revision rate = 0.2%). CONCLUSIONS: This large database analysis quantified complication and revision rates for aTSA and rTSA. We found aTSA and rTSA complication rates of 10.7% and 8.9%, respectively; with revision surgery rates of 5.6% and 2.5%, respectively. The 2 most common complications for each prosthesis type (aTSA: subscapularis/rotator cuff tears, aseptic glenoid loosening; rTSA: acromial/scapular fractures, instability) were unique to each device. The rate of infection was similar for both. Future prosthesis and technique development should work to mitigate these common complication types in order to reduce their rate of occurrence.

The effect of body mass index on internal rotation and function following anatomic and reverse total shoulder arthroplasty.

BACKGROUND: The exact relationship between body mass index (BMI) and internal rotation (IR) before and after total shoulder arthroplasty has not been studied to date. The purpose of this study was to determine the effects of BMI on the preoperative and postoperative shoulder range of motion and function in anatomic (aTSA) and reverse total shoulder arthroplasty (rTSA), and specifically how IR affects patient ability to perform IR-related activities of daily living (ADLs). METHODS: Patients from a prospective multicenter international shoulder arthroplasty registry who underwent primary rTSA (n=1171) and primary aTSA (n=883) were scored preoperatively and at latest follow-up (2-10 years, mean = 3 years) using the Simple Shoulder Test, University of California-Los Angeles shoulder score, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, Constant score, and Shoulder Pain and Disability Index patient-reported outcome measures (PROMs). Measured active abduction, forward flexion, IR, and active and passive external rotation were recorded, and BMI was evaluated as a predictor of motion and patient-reported outcomes. Patient responses to questions regarding the difficulty level of IR-related ADLs were studied. The relationships between BMI, IR, and ability to perform IR-related ADLs were quantified through analysis of variance with post hoc comparisons by Tukey honestly significant difference tests, where significance was denoted as P < .05. RESULTS: BMI was found to be inversely correlated with IR in patients undergoing both aTSA and rTSA, both preoperatively (P < .001 and P = .002) and postoperatively (P < .001 and P < .001). BMI affected the range of motion parameters of forward flexion abduction and external rotation but to a lesser extent than that of IR. Nonobese patients demonstrated significantly greater IR than overweight, obese, and morbidly obese patients postoperatively for aTSA (P < .001). For rTSA, nonobese patients had a significantly greater postoperative IR than obese and morbidly obese patients (P < .001 and P = .011, respectively). For both aTSA and rTSA patients, mean IR scores significantly differed between patients reporting normal function vs. patients reporting slight difficulty, considerable difficulty, or inability to perform IR-related ADLs. Increasing IR demonstrated a significant, positive correlation with all PROMs for both aTSA and rTSA patients (Pearson correlation, P < .001). CONCLUSIONS: BMI is an independent predictor of IR, even when controlling for age, gender, glenosphere size, and subscapularis repair. BMI was inversely correlated with the degree of IR, and decreased IR significantly negatively affected the ability to perform IR-related ADLs. CLINICAL RELEVANCE: Increasing BMI adversely affects shoulder ROM, particularly IR. IR is correlated with the ability to perform ADLs requiring IR in both aTSA and rTSA patients.

Magnetic Resonance Imaging of Pectoralis Major Injuries in an Active Duty Military Cohort: Mechanism Affects Tear Location.

BACKGROUND: Pectoralis major (PM) tendon tears are common injuries in athletic patient populations, where operative repair is largely recommended for maximum functional recovery. The repair varies in difficulty and technique based on the location of the tear within the muscle-tendon unit. Magnetic resonance imagining (MRI) has been reported to be sensitive and specific for identifying the tear location, but the effect of injury mechanism on tear pattern has not been previously investigated. PURPOSE: To examine PM tears in a military patient population and assess the effect of injury mechanism (weightlifting vs high-energy trauma) on the tear pattern and accuracy of MRI interpretation. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Active duty military servicemembers undergoing operative repair of PM tendon tears with corresponding preoperative MRIs from 2 medical centers were identified. Two musculoskeletal fellowship-trained radiologists reviewed imaging studies, reporting the location of the tear within the muscle-tendon unit and the severity of the tear (sternal head vs clavicular head vs both). Radiographic findings were compared against intraoperative findings. Mechanism of injury and timing from injury to imaging and surgery were assessed to determine whether they affected the accuracy of MRI interpretations. RESULTS: A total of 72 patients were included (mean ± SD age, 33.7 ± 7.0 years; 100% male). Mechanisms of injury consisted of 46 weightlifting injuries and 26 high-energy injuries. Interrater reliability was poor for tear location (kappa, 0.162; P = .003) but substantial for extent of tear (kappa, 0.637; P < .0001). MRI had a 51.3% sensitivity and 63.6% specificity for identifying complete tears. MRI had a sensitivity of 73.9% and specificity of 72.2% for avulsion injuries and sensitivity of 75% and specificity of 79.3% for musculotendinous injuries. Mechanism of injury had no effect on extent of the tear but did affect the location of the tear, with a higher rate of avulsion injuries in the high-energy mechanism cohort (81% vs 40%; P = .02). CONCLUSION: The mechanism of injury was found to significantly affect the location of tendon tears. A higher rate of avulsion injuries was found in high-energy injuries than weightlifting injuries. MRI appeared to be less sensitive and specific than previous reports for traumatic PM tendon injuries.

Routine postoperative laboratory tests are unnecessary after primary reverse shoulder arthroplasty.

BACKGROUND: Obtaining postoperative laboratory studies after primary reverse shoulder arthroplasty (RSA) is a common practice. However, justification of this practice remains unclear. This study assesses the utility of routine postoperative laboratory studies in RSA. METHODS: The electronic medical records of 369 patients who underwent RSA over 10 years were retrospectively reviewed. A total of 213 patients qualified for analysis. Primary outcomes were intervention related to abnormal laboratory values, length of stay, and 90-day emergency department visits/readmissions. Multivariate logistic regression analysis was performed to identify risk factors associated with abnormal laboratory values and postoperative visits/readmissions. RESULTS: Of 213 patients analyzed, 188 (88.7%) had abnormal postoperative laboratory values: 69% had an abnormal hemoglobin (Hgb) or hematocrit level, but only 12% underwent interventions. Lower preoperative Hgb was a significant predictor of receiving a transfusion. A significant association existed between abnormal postoperative electrolyte and creatinine levels with lower body mass index (BMI) and higher Charlson Comorbidity Index (CCI). Only 4 patients (1.8%) received non-transfusion related intervention. Emergency department visits were not statistically different between patients with positive or negative laboratory tests (P = .73). CONCLUSION: Because 87.3% of laboratory studies did not influence patient management, we recommend against routine testing for primary RSA. This study demonstrates that the practice of obtaining routine postoperative laboratory studies is not justified. We recommend selectively obtaining a postoperative basic metabolic profile in patients with increased American Society of Anesthesiologists classification and/or CCI with a lower BMI. We also recommend selectively ordering postoperative complete blood count in patients with a lower preoperative Hgb.

Use of electrocautery does not diminish the transmission rate of Cutibacterium acnes compared to a scalpel blade.

Many methods are used during shoulder surgery to prevent wound contamination with Cutibacterium acnes, but there are no accepted standards for prevention. Some surgeons use an electrosurgical instrument instead of a scalpel blade during open shoulder surgery in an effort to prevent deep tissue contamination with C. acnes. We sought to compare the transference rate of C. acnes between a scalpel blade at room temperature and an electrosurgical blade heated to 41°C (temperature of electrosurgical blade after standard deltopectoral approach). In our model, using a scalpel blade versus a heated electrosurgical blade resulted in no difference in pathogen transference.

Use of the Contralateral Glenoid for Calculation of Glenoid Bone Loss: A Cadaveric Anthropometric Study.

PURPOSE: The purpose of this study was to determine if there are significant side-to-side anthropometric differences between paired glenoids. METHODS: Forty-six matched-pair cadaver glenoids were harvested, and their glenoid heights (GHs) and glenoid widths (GWs) were measured with digital calipers. The glenoid surface area was calculated using the standard assumption that the inferior two-thirds of the glenoid is a perfect circle. RESULTS: There was a statistically significant difference between matched-pair GHs of 0.96 ± 3.07 mm (P = .020) and GWs of 0.46 ± 1.64 mm (P = .033). There was a significant difference of glenoid cavity area of 20.30 ± 81.53 mm2 (P = .044), or a difference of ∼3%. A total of 4 of 46 pairs of glenoids (8.6%) showed a difference in width >3 mm. CONCLUSIONS: This study demonstrates the fallacy of use of the contralateral glenoid in measuring glenoid bone loss. Although many paired samples exhibited similar side-to-side glenoid measurements, the number of cadaveric pairs that showed differences of >3 mm was substantial. Caution should be taken when using calculation methods that include this assumption for surgical decision making, as surface area, GW, and GH were all shown to have statistically significant side-to-side differences in their measurements. CLINICAL RELEVANCE: Many methods exist for measuring glenoid bone loss after anterior shoulder dislocation, but some of the current methods may be inaccurate and lead to unreliable estimations.

Exploring Penicillin G as an Intrawound Antibiotic Powder for Prevention of Postoperative Shoulder Infections: Does It Exhibit In Vitro Chondrotoxicity?

Cutibacterium acnes (C. acnes) is a significant insidious pathogen for postoperative infections in shoulder surgery. Studies have demonstrated that certain topical antibiotic powders used have the potential for chondrotoxicity. Benzylpenicillin, commonly referred to as Penicillin G (Pen G) has the lowest minimum inhibitory concentration (MIC) for C. acnes. There is no research regarding the topical application of Pen G during shoulder surgery, nor has its chondrocyte toxicity been previously investigated. This study sought to characterize the in vitro chondrocyte toxicity of Pen G. Culture-derived bovine chondrocytes were exposed to serial Pen G concentrations and compared with a positive and negative control. A negative control of growth medium and positive control of 1% Triton solution. The chondrocyte viability was assessed via spectrophotometer absorbance. The treatment groups were analyzed using one-way repeated measures analysis of variance and Pearson's correlation analysis. The chondrocyte viability was significantly higher for all Pen G concentrations as compared with the positive control (p < 0.001). All concentrations of Pen G exhibited continued chondrocyte metabolic activity over time. Analysis of variance, independent of time, demonstrated no significant decrease in chondrocyte viability for Pen G concentrations ≤6.25 mg/ml, as compared with the negative control (p > 0.05). Pen G demonstrated a significant negative correlation with its concentration and absorbance (r = 0.371, p < 0.001), however, concentrations ≤6.25 mg/ml did not demonstrate a significant decrease in chondrocyte viability (p = 0.063). Pen G in concentrations appropriate for C. acnes is not significantly chondrotoxic and may be safe for intrawound application. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:726-730, 2020.