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Background This study sought to determine if preoperative forward elevation (FE) weakness affects outcomes of anatomic (aTSA) and reverse total shoulder arthroplasty (rTSA) for patients with rotator cuff-intact glenohumeral osteoarthritis (RCI-GHOA). Methods A retrospective review of a single institution’s prospectively collected shoulder arthroplasty database was performed between 2007 and 2020, including 333 aTSAs and 155 rTSAs for primary RCI-GHOA with a minimum 2-year follow-up. Defining preoperative weakness as FE strength ≤4.9 lb (2.2 kg), three cohorts were matched 1:1:1 by age, sex, and follow-up: weak (n=82) to normal aTSAs, weak (n=44) to normal rTSAs, and weak aTSAs (n=61) to weak rTSAs. Compared outcomes included range of motion, outcome scores, and complication and revision rates at latest follow-up. Results Weak aTSAs and weak rTSAs achieved similar postoperative outcome measures to normal aTSAs and normal rTSAs, respectively (P>0.05). Compared to weak rTSAs, weak aTSAs achieved superior postoperative passive (P=0.006) and active external rotation (ER) (P=0.014) but less favorable postoperative Shoulder Pain and Disability Index (P=0.032), American Shoulder and Elbow Surgeons (P=0.024), and University of California, Los Angeles scores (P=0.008). Weak aTSAs achieved the minimal clinically important difference (MCID) and substantial clinical benefit at a lower rate for abduction (P=0.045 and P=0.003) and FE (P=0.011 and P=0.001). Weak aTSAs had a higher revision rate (P=0.025) but a similar complication rate (P=0.291) compared to weak rTSAs. Conclusions Patients with RCI-GHOA and preoperative FE weakness obtain postoperative outcomes similar to patients with normal preoperative strength after either aTSA or rTSA. Preoperatively, weak aTSAs achieved greater ER but lower rates of clinically relevant improvement in overhead motion compared to weak rTSAs. Level of evidence III.

Background: Biomechanical research demonstrates increased subscapularis abduction range of motion (ROM) when the tendon’s upper two-thirds is repaired over-the-top of the center of rotation during reverse shoulder arthroplasty (RSA). This study compares the clinical outcomes of patients undergoing RSA with over-the-top subscapularis repair (OTTR) to patients without repair. Methods: We retrospectively reviewed 97 consecutive RSAs with either OTTR of the subscapularis (N = 75) or no repair (N = 22). Repair was attempted in all patients but not performed if the subscapularis could not be brought to the over-the-top position in 20° of external rotation (ER) and 30° of abduction. Improvements in ROM were compared to the minimal clinically important difference for RSA. Results: The mean follow-up was 3.8 ± 1.6 years. Demographics were similar between groups. Preoperatively, patients undergoing repair had greater ER when compared to those without repair (15 ± 16° vs. 5 ± 12°, P = .003). Postoperatively, patients undergoing repair had greater forward elevation (132 ± 21° vs. 126 ± 22°, P = .268) and abduction (114 ± 26° vs. 106 ± 23°, P = .193) with both exceeding the minimal clinically important difference (−2.9° and −1.9°, respectively); however, not statistically significant. Patients with repair were more frequently able to reach the small of their back postoperatively (65% vs. 21%, P = .006) but had less improvement in ER (13 ± 20° vs. 24 ± 20°, P = .028). Postoperative outcome scores, complications, and reoperations were similar between groups. Discussion: OTTR of the subscapularis in RSA had similar ROM and outcome scores compared to no repair, but a significantly larger proportion of patients with repair achieved functional internal rotation to the small of the back. ER limitations seen after conventional repair may also apply to this novel technique, but without a corresponding detrimental effect on forward elevation or abduction.

Epineural scarring following previous carpal or cubital tunnel release can lead to pain and permanent dysfunction. To prevent this cascade, nerve wraps are an option. The purpose of this study was to evaluate outcomes following use of VersaWrap nerve protector during surgical decompression and neurolysis in patients with recurrent compressive neuropathies in the upper extremity. Twenty patients comprised the patient cohort, with a mean postoperative follow-up time of 139 days (range: 42–356 days). There were 13 females and 7 males, with a mean age of 43.4 years. Fourteen surgeries were performed for revision cubital tunnel, 5 for revision carpal tunnel, and 1 for revision radial tunnel syndrome. Average duration of symptoms prior to revision surgery with VersaWrap was 2 years (range 9 months to 6 years). Postoperatively, the mean DASH score was 57.7 and VAS 3.1. Mean s2PD median distribution was 7.3, s2PD ulnar distribution 8.9, m2PD median distribution 6.9 and m2PD ulnar distribution 7.3. All patients had subjective improvement of symptoms and were satisfied with their result. No patients in our cohort required further revisional surgery. In conclusion, the use of VersaWrap as a nerve protector following revision surgery for recurrent compressive neuropathies in the upper extremity was safe and effective.Level of Evidence: IV; retrospective case series

Disease tolerance, a host’s ability to limit damage from a given parasite burden, is quantified by the relationship between pathogen load and host survival or reproduction. Dermo disease, caused by the protozoan parasite P. marinus, negatively impacts survival in both wild and cultured eastern oyster (C. virginica) populations. Resistance to P. marinus has been the focus of previous studies, but tolerance also has important consequences for disease management in cultured and wild populations. In this study we measured dermo tolerance and evaluated global expression patterns of two sensitive and two tolerant eastern oyster families experimentally challenged with distinct doses of P. marinus (0, 106, 107, and 108 parasite spores per gram wet weight, n = 3–5 individuals per family per dose). Weighted Gene Correlation Network Analysis (WGCNA) identified several modules correlated with increasing parasite dose/infection intensity, as well as phenotype. Modules positively correlated with dose included transcripts and enriched GO terms related to hemocyte activation and cell cycle activity. Additionally, these modules included G-protein coupled receptor, toll-like receptor, and tumor necrosis factor pathways, which are important for immune effector molecule and apoptosis activation. Increased metabolic activity was also positively correlated with treatment. The module negatively correlated with infection intensity was enriched with GO terms associated with normal cellular activity and growth, indicating a trade-off with increased immune response. The module positively correlated with the tolerant phenotype was enriched for transcripts associated with “programmed cell death” and contained a large number of tripartite motif-containing proteins. Differential expression analysis was also performed on the 108 dosed group using the most sensitive family as the comparison reference. Results were consistent with the network analysis, but signals for “programmed cell death” and serine protease inhibitors were stronger in one tolerant family than the other, suggesting that there are multiple avenues for disease tolerance. These results provide new insight for defining dermo response traits and have important implications for applying selective breeding for disease management.

Abstract Background Dinosaurs dominated terrestrial environments for over 100 million years due in part to innovative feeding strategies. Although a range of dental adaptations was present in Late Jurassic dinosaurs, it is unclear whether dinosaur ecosystems exhibited patterns of tooth disparity and dietary correlation similar to those of modern amniotes, in which carnivores possess simple teeth and herbivores exhibit complex dentitions. To investigate these patterns, we quantified dental shape in Late Jurassic dinosaurs to test relationships between diet and dental complexity. Results Here, we show that Late Jurassic dinosaurs exhibited a disparity of dental complexities on par with those of modern saurians. Theropods possess relatively simple teeth, in spite of the range of morphologies tested, and is consistent with their inferred carnivorous habits. Ornithischians, in contrast, have complex dentitions, corresponding to herbivorous habits. The dentitions of macronarian sauropods are similar to some ornithischians and living herbivorous squamates but slightly more complex than other sauropods. In particular, all diplodocoid sauropods investigated possess remarkably simple teeth. The existence of simple teeth in diplodocoids, however, contrasts with the pattern observed in nearly all known herbivores (living or extinct). Conclusions Sauropod dinosaurs exhibit a novel approach to herbivory not yet observed in other amniotes. We demonstrate that sauropod tooth complexity is related to tooth replacement rate rather than diet, which contrasts with the results from mammals and saurians. This relationship is unique to the sauropod clade, with ornithischians and theropods displaying the patterns observed in other groups. The decoupling of herbivory and tooth complexity paired with a correlation between complexity and replacement rate demonstrates a novel evolutionary strategy for plant consumption in sauropod dinosaurs.