Background: To compare clinical outcomes following lateralized reverse shoulder arthroplasty (RSA) versus RSA with latissimus dorsi transfer (LDT) in patients with poor preoperative active external rotation (ER). Methods: We performed a systematic review per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We queried PubMed/Medline, Embase, Web of Science, and Cochrane databases to identify articles reporting clinical outcomes of RSA with LDT or lateralized RSA alone performed in patients with preoperative ER ≤0°. Our primary outcomes were active ER, active forward elevation (FE), Constant score, and the incidence of complications. Results: We included 12 RSA with LDT studies with 188 shoulders and 4 lateralized RSA without transfer studies with 250 shoulders. Mean preoperative ER in RSA with LDT was –14°, while mean preoperative ER in lateralized RSA alone was –11°. Lateralized RSA alone was associated with superior postoperative ER (28° vs. 22°, P=0.010) and Constant score (69 vs. 65, P=0.014), but similar postoperative FE (P=0.590). Pre- to postoperative improvement in ER and FE was similar between cohorts. RSA with LDT had a higher incidence of nerve-related complications (2.1% vs. 0%) and dislocation (2.8% vs. 0.8%) compared to lateralized RSA alone. Conclusions Both RSA with LDT and lateralized RSA are reliable options to restore ER in patients with significantly limited preoperative ER. Our analysis suggests that lateralized RSA alone is superior to RSA with LDT in patients with either a medialized or lateralized implant design and confers a lower risk of complications, particularly nerve injury and dislocation. However, the addition of an LDT may still be indicated in certain patient populations with very severe ER loss.Level of evidence: IV.

Background: To compare clinical outcomes following lateralized reverse shoulder arthroplasty (RSA) versus RSA with latissimus dorsi transfer (LDT) in patients with poor preoperative active external rotation (ER). Methods: We performed a systematic review per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We queried PubMed/Medline, Embase, Web of Science, and Cochrane databases to identify articles reporting clinical outcomes of RSA with LDT or lateralized RSA alone performed in patients with preoperative ER ≤0°. Our primary outcomes were active ER, active forward elevation (FE), Constant score, and the incidence of complications. Results: We included 12 RSA with LDT studies with 188 shoulders and 4 lateralized RSA without transfer studies with 250 shoulders. Mean preoperative ER in RSA with LDT was –14°, while mean preoperative ER in lateralized RSA alone was –11°. Lateralized RSA alone was associated with superior postoperative ER (28° vs. 22°, P=0.010) and Constant score (69 vs. 65, P=0.014), but similar postoperative FE (P=0.590). Pre- to postoperative improvement in ER and FE was similar between cohorts. RSA with LDT had a higher incidence of nerve-related complications (2.1% vs. 0%) and dislocation (2.8% vs. 0.8%) compared to lateralized RSA alone. Conclusions Both RSA with LDT and lateralized RSA are reliable options to restore ER in patients with significantly limited preoperative ER. Our analysis suggests that lateralized RSA alone is superior to RSA with LDT in patients with either a medialized or lateralized implant design and confers a lower risk of complications, particularly nerve injury and dislocation. However, the addition of an LDT may still be indicated in certain patient populations with very severe ER loss.Level of evidence: IV.

Background: To compare clinical outcomes following lateralized reverse shoulder arthroplasty (RSA) versus RSA with latissimus dorsi transfer (LDT) in patients with poor preoperative active external rotation (ER). Methods: We performed a systematic review per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We queried PubMed/Medline, Embase, Web of Science, and Cochrane databases to identify articles reporting clinical outcomes of RSA with LDT or lateralized RSA alone performed in patients with preoperative ER ≤0°. Our primary outcomes were active ER, active forward elevation (FE), Constant score, and the incidence of complications. Results: We included 12 RSA with LDT studies with 188 shoulders and 4 lateralized RSA without transfer studies with 250 shoulders. Mean preoperative ER in RSA with LDT was –14°, while mean preoperative ER in lateralized RSA alone was –11°. Lateralized RSA alone was associated with superior postoperative ER (28° vs. 22°, P=0.010) and Constant score (69 vs. 65, P=0.014), but similar postoperative FE (P=0.590). Pre- to postoperative improvement in ER and FE was similar between cohorts. RSA with LDT had a higher incidence of nerve-related complications (2.1% vs. 0%) and dislocation (2.8% vs. 0.8%) compared to lateralized RSA alone. Conclusions Both RSA with LDT and lateralized RSA are reliable options to restore ER in patients with significantly limited preoperative ER. Our analysis suggests that lateralized RSA alone is superior to RSA with LDT in patients with either a medialized or lateralized implant design and confers a lower risk of complications, particularly nerve injury and dislocation. However, the addition of an LDT may still be indicated in certain patient populations with very severe ER loss.Level of evidence: IV.

Background: To compare clinical outcomes following lateralized reverse shoulder arthroplasty (RSA) versus RSA with latissimus dorsi transfer (LDT) in patients with poor preoperative active external rotation (ER). Methods: We performed a systematic review per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We queried PubMed/Medline, Embase, Web of Science, and Cochrane databases to identify articles reporting clinical outcomes of RSA with LDT or lateralized RSA alone performed in patients with preoperative ER ≤0°. Our primary outcomes were active ER, active forward elevation (FE), Constant score, and the incidence of complications. Results: We included 12 RSA with LDT studies with 188 shoulders and 4 lateralized RSA without transfer studies with 250 shoulders. Mean preoperative ER in RSA with LDT was –14°, while mean preoperative ER in lateralized RSA alone was –11°. Lateralized RSA alone was associated with superior postoperative ER (28° vs. 22°, P=0.010) and Constant score (69 vs. 65, P=0.014), but similar postoperative FE (P=0.590). Pre- to postoperative improvement in ER and FE was similar between cohorts. RSA with LDT had a higher incidence of nerve-related complications (2.1% vs. 0%) and dislocation (2.8% vs. 0.8%) compared to lateralized RSA alone. Conclusions Both RSA with LDT and lateralized RSA are reliable options to restore ER in patients with significantly limited preoperative ER. Our analysis suggests that lateralized RSA alone is superior to RSA with LDT in patients with either a medialized or lateralized implant design and confers a lower risk of complications, particularly nerve injury and dislocation. However, the addition of an LDT may still be indicated in certain patient populations with very severe ER loss.Level of evidence: IV.

Genetic variation in apolipoprotein E (APOE) influences Alzheimer's disease (AD) risk. APOE ε4 alleles are the strongest genetic risk factor for late onset sporadic AD. The AD risk is dose dependent, as those carrying one APOE ε4 allele have a 2-3-fold increased risk, while those carrying two ε4 alleles have a 10-15-fold increased risk. Individuals carrying APOE ε2 alleles have lower AD risk and those carrying APOE ε3 alleles have neutral risk. APOE is a lipoprotein which functions in lipid transport, metabolism, and inflammatory modulation. Isoform specific effects of APOE within the brain include alterations to Aβ, tau, neuroinflammation, and metabolism. Here we review the association of APOE with AD, the APOE isoform specific effects within brain and periphery, and potential therapeutics.

Recent data suggest that cystic fibrosis transmembrane conductance regulator (CFTR) gene alterations negatively impact male fertility beyond obstruction. We sought to compare gene alterations, sperm retrieval rates, and intracytoplasmic sperm injection (ICSI) outcomes among men with cystic fibrosis (CF) disease and congenital bilateral absence of the vas deferens (CBAVD) only. We retrospectively evaluated all men who underwent surgical sperm retrieval at two academic, high-volume andrology centers from 2010 to 2018. Only men with documented CFTR alterations and obstructive azoospermia from either CBAVD or CF were included. Differences between groups for CFTR abnormality, sperm retrieval, and ICSI outcomes were statistically analyzed. Overall, 39 patients were included with 10 in the CF and 29 in the CBAVD groups. Surgical sperm retrieval rates were significantly lower in the CF group for sperm concentration (14.8 × 10