Faculty Bibliography

PURPOSE/OBJECTIVE:Coracoid fracture is a rare injury. The aim of this study is to present the demographics, clinical and radiologic characteristics, and outcomes of coracoid fracture in a cohort of 32 patients. METHODS:We queried our institutional electronic medical record database (years 2012-2020) to identify patients with coracoid fractures using specific International Classification of Disease-10 codes. Demographic data, injury details including mechanism of injury and associated injuries, imaging performed, and treatment outcomes were obtained from retrospective chart review. A radiologist reviewed all available imaging studies (radiographs/CT/MRI) and classified the fractures according to Ogawa and Eyres classifications. Missed diagnoses were determined by comparing initial imaging reports with the follow-up imaging obtained in the office. RESULTS:Thirty-two patients with coracoid fractures were identified during the study period. Sixteen fractures (50%) occurred in the setting of low-energy trauma. Twelve fractures were missed on initial radiographs, and diagnosis with three-view radiographs (AP, scapular-Y and axillary) was 88% compared to 33% (p < 0.03) with two views (AP, scapular-Y). The majority of fractures were non-displaced (94%), and 56% were Ogawa Type-II fractures. Associated injuries were seen in 81% of patients. Most fractures (94%) were treated without surgery with excellent outcomes. CONCLUSION/CONCLUSIONS:Coracoid fractures continue to be a rare injury. In contrast to previous studies, in this case series of 32 patients, half of the fractures were associated with low-energy trauma, which correlated with higher percentage of non-displaced fractures and Ogawa Type-II fractures. Addition of the axillary view in the trauma radiographic series significantly improved the initial fracture detection rate. LEVEL IV/UNASSIGNED:Retrospective study.

OBJECTIVE:To compare MRI with 3D reconstructions and 3D-CT with respect to assessment of glenoid wear in osteoarthritic shoulders. METHODS:3D reconstructions were generated for CT and MR (utilizing the Dixon technique) imaging performed on 29 osteoarthritic shoulders. Two reviewers independently performed glenoid morphometric measurements and evaluated glenoid erosion. Mean differences between the two modalities were calculated. Inter-observer agreement was calculated using kappa coefficient. RESULTS:The combined mean absolute difference (bias) in glenoid version between 3D-CT and 3D-MRI was 2.7° ± 1.6° (range 0.15-7.85, P value = 0.7). The combined mean absolute difference in glenoid inclination between 3D-CT and 3D-MRI was 6.8° ± 4.1° (range 0.8°-15.75°, P value = 0.17). No significant inter-reader variation in glenoid version and inclination measurements on 3D-CT and 3D-MRI was found (P > 0.05). The inter-reader reliability for both CT and MRI was high for Walch grading of glenoid bone loss (κ = 1, κ = 0.81, respectively). CONCLUSIONS:3D-MRI is comparable to 3D-CT with respect to axial glenoid bone loss, as measured by glenoid version. However, for coronal bone loss estimation, measured by glenoid inclination, 3D-CT remains the gold standard. Thus, 3D-MR can be used as an alternative for preoperative assessment of glenoid version in arthritic shoulders.

INTRODUCTION/BACKGROUND:Glenoid baseplate augments have recently been introduced as a way of managing glenoid monoplanar or biplanar abnormalities in reverse shoulder arthroplasty (RSA). The purpose of this study is to evaluate the difference in clinical outcomes, complications, and revision rates between augmented and standard baseplates in RSA for rotator cuff arthropathy patients with glenoid deformity. METHODS:A multicenter retrospective analysis of 171 patients with glenoid bone loss who underwent RSA with and without augmented baseplates was performed. Preoperative inclusion criteria included: minimum follow-up of 2 years and preoperative retroversion of 15 to 30 degrees and/or a beta angle 70 to 80 degrees. Version and beta angle measured on CT, when available, and plain X-rays. Shoulder range of motion (ROM) and patient-reported outcomes were obtained from preoperative and multiple postoperative timepoints. RESULTS:The study consisted of 84 standard baseplate patients and 87 augmented baseplate patients. The augment cohort had greater mean preoperative glenoid retroversion (17 vs. 9 degrees, p<0.001). At 5+ year follow-up, the increase in postoperative active abduction (52 vs. 31 degrees, p=0.023), forward flexion (58 vs. 35 degrees, p=0.020) and internal rotation score (2.8 vs. 1.1 degrees, p=0.001) was significantly greater in the augment cohort. Additionally, 5+ year follow-up ASES score (87.0 ± 16.6 vs. 75.9 ± 22.4, p=0.022), Constant score (78.0 ± 9.7 vs. 64.6 ± 15.1, p<0.001) and Shoulder Arthroplasty Smart score (81.2 ± 6.5 vs. 71.2 ± 13.6, p=0.003) were significantly higher in the augment cohort. Revision rate was low overall with no difference between the augment and no augment groups (0.7% vs. 3.0%, p=0.151). CONCLUSION/CONCLUSIONS:In comparing augments to standard non-augment baseplates in the setting of RSA with glenoid deformity, our results demonstrate greater postoperative improvements in multiple planes of active range of motion in the augment cohort. Additionally, the augment cohort demonstrated greater postoperative level and improvement in scores for multiple clinical outcome metrics up to 5+ years of follow-up with no difference in complication or revision rates, supporting the use of augmented glenoid baseplates in RSA with glenoid deformity.

INTRODUCTION/BACKGROUND:Since the introduction of the Grammont style reverse total shoulder arthroplasty (RTSA), the humeral stem design has been modified with improved clinical outcomes. Two distinct humeral designs have been utilized extensively: the inlay where the humeral tray is seated within the metaphysis and the onlay design where the humerus tray sits on the metaphysis at the level of the humeral neck cut. The purpose of this systematic review is to determine if there are differences in clinical outcomes and complication rates between these designs. METHODS:The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to perform this systematic review. A search was performed on Medline, PubMed, and Embase to identify all studies comparing clinical results of both humeral designs. Primary outcomes included patient-reported outcomes measures (PROMs), shoulder range of motion, and incidence of complications. RESULTS:From the 156 identified publications, 12 studies were included in the final review. A total of 1447 patients were included with a minimum follow-up of 12 months. At final follow-up, both implants demonstrated significant improvements in comparison to preoperative baseline. When comparing inlay versus onlay groups, the American Shoulder and Elbow Surgeons (ASES) score was higher in the inlay group (mean difference of 2.53 [95% CI: 0.27-4.78] p=0.03). Postoperative motion, even if statically greater in the onlay group (difference in forward flexion 5°(p<0.001), abduction 3° (p=0.003) and external rotation 4°(p<0.001)) are not clinically different. When comparing complications, the inlay group reported more instances of scapular notching (93/322 versus 70/415, OR 0.35 p<0.001) but fewer scapular spine fractures (26/727 versus 21/559, p=0.09). DISCUSSION/CONCLUSIONS:Inlay and onlay humeral tray designs in reverse total shoulder arthroplasty demonstrate similar clinical improvements postoperatively. The onlay implants have low rate of scapular notching but higher rate of scapular spine fracture. Understanding the strength and weaknesses of the two humeral tray designs is important to provide surgeons with options to tailor surgical plan for high risk patients.

INTRODUCTION/BACKGROUND:This study's purpose is to compare clinical and radiographic outcomes of primary anatomic total shoulder arthroplasty (aTSA) and primary reverse total shoulder arthroplasty (rTSA) patients with osteoarthritis (OA) and an intact rotator cuff with no previous history of shoulder surgery using a single platform TSA system at a minimum follow-up of 2 years. METHODS:A total of 370 aTSA patients and 370 rTSA patients matched for age, sex, and length of follow-up from an international multi-institutional Western Institutional Review Board approved registry with a minimum 2-year follow-up were reviewed for this study. All patients had a diagnosis of OA, an intact rotator cuff, and no previous shoulder surgery. All patients were evaluated and scored preoperatively and at latest follow-up using six outcome scoring metrics and four active range of motion measurements. RESULTS:Mean follow-up was 41 months, and the mean age was 73 years. Preoperatively, the rTSA patients had lower outcome metrics and less motion. Postoperatively, aTSA and rTSA patients had similar clinical outcomes, motion, and function, with the only exception being greater external rotation in aTSA exceeding the minimal clinically important difference. Pain relief was excellent, and patient satisfaction was high in both groups. Humeral radiolucent lines were similar in both groups (8%). Complications were significantly higher with aTSA (aTSA = 4.9%; rTSA = 2.2%; P = 0.045), but revisions were similar (aTSA = 3.2%; rTSA = 1.4%; P = 0.086). CONCLUSION/CONCLUSIONS:At a mean of 41 month follow-up, primary aTSA and rTSA patients with OA and an intact rotator cuff with no previous history of shoulder surgery had similar clinical and radiographic outcomes. Greater external rotation was noted in aTSA patients at follow-up. However, aTSA patients had a significantly greater rate of complications compared with rTSA patients. rTSA is a viable treatment option in patients with an intact rotator cuff and no previous shoulder surgery, offering similar clinical outcomes with a lower complication rate. LEVEL OF EVIDENCE/METHODS:Level III.

The Patient-Reported Outcomes Measurement Information System Upper Extremity Computer Adaptive Test (PROMIS UE CAT) is a newer patient-reported outcome measure for upper extremity physical function. To date, no longitudinal study exists assessing PROMIS UE CAT responsiveness in patients undergoing shoulder arthroplasty. The purpose of this prospective longitudinal study is to report PROMIS UE CAT responsiveness to change and correlation to legacy instruments in patients undergoing total shoulder arthroplasty (TSA). Ninety-six patients (97 shoulders) undergoing TSA completed the PROMIS UE, Oxford Shoulder Score (OSS), American Shoulder and Elbow Surgeons (ASES), and Simple Shoulder Test (SST) preoperatively and postoperatively at 6 weeks, 12 weeks, and after 6 months. Spearman's correlation coefficients (r) were calculated between PROMIS UE and other scores at each time-point. Responsiveness to change was assessed using the effect size (Cohen's d) and standardized response mean compared with the preoperative time-point. Floor and ceiling effects were also assessed. PROMIS UE CAT demonstrated positive responsiveness at all time-points after TSA. It demonstrated excellent correlation (range: 0.68-0.84) with ASES, SST, and OSS at all postoperative time-points, but the correlation was weaker (r < 0.6, except OSS) preoperatively. Only OSS and SST showed ceiling effects at the 6-12-month time-point (16.8% and 18.2%, respectively). PROMIS UE CAT responsiveness to change and strength of correlation with legacy instruments improves with time elapsed after TSA. Further quantification of meaningful responsiveness to change will require estimation of the minimal clinically important difference and substantial clinical benefit for PROMIS UE CAT.

INTRODUCTION/BACKGROUND:While lateralization of the glenohumeral center of rotation during reverse shoulder arthroplasty (RSA) has benefits of maintaining tension on the remaining rotator cuff and decreasing implant impingement on the glenoid, few clinical studies have evaluated the isolated effect of glenoid lateralization in RSA. The purpose of this study was to evaluate if clinical outcomes are affected by isolated glenosphere lateralization using a single implant design. METHODS:A retrospective review from a multicenter shoulder arthroplasty research database was performed between 2011 and 2018 using a single implant system to perform this case-controlled study. Inclusion criteria included primary RSAs with adequate preoperative and postoperative active and passive range of motion (ROM) measurements, outcome scores, and a minimum two-year follow-up. Revision shoulder arthroplasties and RSA for fractures were excluded from analysis. 102 RSAs (61 females, 41 males) using a +4mm lateralized glenosphere were compared to 102 sex, age, and glenosphere diameter matched control shoulders with standard glenospheres (whose center of rotation (CoR) is 2mm lateral to the glenoid fossa). The mean age at surgery was 70.4 years. Mean follow up was 43.6 + 18.9 months. All RSAs were performed with the same implant system (Equinoxe, Exactech, Gainesville, FL). Clinical outcome measures included ROM, ASES, Constant, UCLA, SST, SPADI scores, and VAS pain scores. We used the chi-squared test and Fisher exact test for bivariate analysis and the student t-test for continuous variables. RESULTS:Both groups were of similar average age and follow-up. They also had comparable rates of prior surgery and comorbidities. The lateralized glenosphere group had a slightly higher BMI (31.2 vs. 29.2, p=0.04). Both groups demonstrated significant improvements in all outcome scores that exceeded the MCID and the SCB. The groups demonstrated similar preoperative, postoperative and improvements in ROM as well as outcome scores. The overall complication rate was similar between groups (4% in lateralized and 5% in controls, p=0.73). Scapular or acromial fractures differences were not statistically significant between groups (1% in lateralized group vs. 3% in standard group, p=0.31). Scapular notching was more frequent in the standard group compared to the lateralized group (9% vs. 2%, p=0.03). CONCLUSION/CONCLUSIONS:In a medialized glenosphere/lateralized humerus design, a +4mm lateralized glenosphere provided no significant advantage in postoperative pain, ROM, or outcome scores. However, lateralized glenospheres did demonstrate significantly lower scapular notching rates. LEVEL OF EVIDENCE/METHODS:III; Retrospective Cohort Comparison; Treatment Study.