Variations in the Anatomic Morphology of the Scapular Spine and Implications on Fracture After Reverse Shoulder Arthroplasty.

INTRODUCTION: This study evaluates the role of anatomic scapular morphology in acromion and scapular spine fracture (SSAF) risk after reverse shoulder arthroplasty (RSA). METHODS: Twelve scapular measurements were captured based on pilot study data, including scapular width measurements at the acromion (Z1), middle of the scapular spine (Z2), and medial to the first major angulation (Z3). Measurements were applied to 3D-CT scans from patients who sustained SSAF after RSA (SSAF group) and compared with those who did not (control group). Measurements were done by four investigators, and the intraclass correlation coefficient was calculated. Regression analysis determined trends in fracture incidence. RESULTS: One hundred forty-nine patients from two separate surgeons (J.L., A.M.) were matched by age and surgical indication of whom 51 sustained SSAF after reverse shoulder arthroplasty. Average ages for the SSAF and control cohorts were 78.6 and 72.1 years, respectively. Among the SSAF group, 15 were Levy type I, 26 Levy type II, and 10 Levy type 3 fractures. The intraclass correlation coefficient of Z1, Z2, and Z3 measurements was excellent (0.92, 0.92, and 0.94, respectively). Zone 1 and 3 measurements for the control group were 18.6 ± 3.7 mm and 3.2 ± 1.0 mm, respectively, compared with 22.5 ± 5.9 mm and 2.0 ± 0.70 mm in the SSAF group, respectively. The fracture group trended toward larger Z1 and smaller Z3 measurements. The average scapular spine proportion (SSP), Z1/Z3, was significantly greater in the control 6.20 ± 1.80 versus (12.60 ± 6.30; P < 0.05). Regression analysis showed a scapular spine proportion of ≤5 was associated with a fracture risk <5%, whereas an SSP of 9.2 correlated with a 50% fracture risk. DISCUSSION: Patients with a thicker acromions (Z1) and thinner medial scapular spines (Z3) have increased fracture risk. Understanding anatomic scapular morphology may allow for better identification of high-risk patients preoperatively.

Patient adherence to therapy after switch to aflibercept from bevacizumab or ranibizumab for treatment-refractory neovascular age-related macular degeneration.

PURPOSE: Clinical trials have demonstrated that switching patients from intravitreal bevacizumab (IVB) or ranibizumab (IVR) to aflibercept (IVA) for treatment-refractory neovascular age-related macular degeneration (nAMD) can decrease the injection frequency. This study evaluated whether there was a difference in the rate of injections or nonadherent events after switching therapies. METHODS: The study comprised a retrospective, cross-sectional analysis of patients treated for nAMD from 2010 to 2018 who received ≥3 intravitreal injections of IVB/IVR prior to switching to IVA because of treatment-refractory nAMD. The treatment index, outcomes, and adherence to treatment were compared between both treatment regimens. RESULTS: Sixty-two patients (67 eyes) met inclusion criteria. There was no change in the treatment index (0.65 versus 0.66, P = 0.650) or the number of nonadherent events (33 versus 36, P = 0.760) after the switch from IVB/IVR to IVA. Central macular thickness (CMT) increased 7.7%±13.8% in eyes that had a nonadherent event (283±69 µm to 304±75 µm after resuming care, P = 0.039). There was no short-term impact on visual acuity (VA) for this subset of eyes (0.387±0.202 LogMAR versus 0.365±0.156 LogMAR, P = 0.636). Patients who had nonadherent events ended the study with similar VA compared with patients who had no treatment lapses (0.370±0.616 LogMAR versus 0.337±0.638 LogMAR, P = 0.843). CONCLUSION: Switching from IVB/ IVR to IVA for treatment-refractory nAMD in a real-world setting does not reduce the treatment index or increase adherence to treatment. Although there were short-term anatomical effects resulting from missed treatments, VA remained stable.