The Buford Complex Redefined: A Pathologic Morphology in Sheep's Clothing.

Background: Considered a normal anatomic variant, the Buford complex has not been studied in children. Hypothesis: A Buford complex is not a normal anatomic variant and would, therefore, be present at a lower rate than that seen in the adult population. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Measurements were recorded from magnetic resonance imaging performed over 13 years in children aged ≤11 years for various pathologies unrelated to glenohumeral instability. Interrater reliability was determined to identify Buford complexes, sublabral foramens and tears, and normal shoulders via 16 preadolescent and adolescent patients with confirmed arthroscopic correlation. The Buford complex and labral foramen rates were then compared with a published rate in adults using a binomial probability test. Results: A total of 122 children (62 girls; mean age, 6.4 years [age range, 2 months-10.9 years]) were evaluated. Interrater reliability was 0.846 (95% CI, 0.56-1) to identify anterosuperior labral variants. The expected sublabral foramen count was 23 children, but only 1 was identified (P < .001). The expected Buford complex count was 8 children, but none could be identified (P < .001). Conclusion: The absence of Buford complexes and the significant reduction in sublabral foramen abundance in younger children suggest that these anatomic variants are more likely to be developmental than congenital. The distinct possibility that these previously considered normal variants are truly pathologic findings cannot be ignored. Evidence of a Buford complex could potentially signify an underlying, long-term shoulder instability issue to the treating provider that warrants further investigation or management.

Do all patients with history of pelvic ring injuries need a cesarean section? - A survey of orthopaedic and obstetric providers.

OBJECTIVE(S): The recommended mode of delivery following pelvic ring fractures with surgical fixation is unclear. The objective of this study was to assess expert opinions from orthopaedic surgeons and obstetrician gynecologists on their recommended delivery recommendations for pregnant individuals with a history of pelvic ring injury, and to see if there was any difference in recommendations between the two specialties, and what factors influenced recommendations. STUDY DESIGN: An electronic, web-based survey was administered to a convenience sample of orthopaedic surgeons and obstetrician gynecologists, via advertisement to members of the Orthopaedic Trauma Association (OTA), the Society for Maternal Fetal Medicine, and querying obstetrician gynecologists practicing within the Military Health System. The survey was administered from November 2021 to December 2022. A two-proportion z-test, Chi-square or Fisher's Exact Test, and descriptive statistics were used to analyze data. RESULTS: Survey respondents included 44 orthopaedic surgeons and 37 obstetricians. A total of 74 % obstetricians would recommend a trial of labor with hardware in place, while orthopaedic surgeon's recommendations varied based on the type of fixation. Forty four, 100 % of orthopaedic surgeons, recommended trial of labor if non-operative pelvic injury or unilateral posterior fixation only, 88 % recommended trial of labor if bilateral posterior fixation only, and 47.7 % for anterior trans-symphyseal plating only, 50 % for unilateral posterior and trans-symphyseal plating, and 43.2 % for bilateral posterior fixation with trans-symphyseal plating. CONCLUSIONS: The results of these surveys demonstrate the lack of consensus as to the most appropriate birth plan for patients with a history of pelvic ring injuries. Vaginal delivery following pelvic ring fracture and fixation is possible, yet these patients are significantly more likely to undergo cesarean section than the general population. As such, we recommend that women who become pregnant after operative treatment of a pelvic ring injury develop an in-depth birthing plan with their obstetrician to determine the best course.

Identification and characterization of alternative sites and molecular probes for SARS-CoV-2 target proteins.

Three protein targets from SARS-CoV-2, the viral pathogen that causes COVID-19, are studied: the main protease, the 2'-O-RNA methyltransferase, and the nucleocapsid (N) protein. For the main protease, the nucleophilicity of the catalytic cysteine C145 is enabled by coupling to three histidine residues, H163 and H164 and catalytic dyad partner H41. These electrostatic couplings enable significant population of the deprotonated state of C145. For the RNA methyltransferase, the catalytic lysine K6968 that serves as a Brønsted base has significant population of its deprotonated state via strong coupling with K6844 and Y6845. For the main protease, Partial Order Optimum Likelihood (POOL) predicts two clusters of biochemically active residues; one includes the catalytic H41 and C145 and neighboring residues. The other surrounds a second pocket adjacent to the catalytic site and includes S1 residues F140, L141, H163, E166, and H172 and also S2 residue D187. This secondary recognition site could serve as an alternative target for the design of molecular probes. From in silico screening of library compounds, ligands with predicted affinity for the secondary site are reported. For the NSP16-NSP10 complex that comprises the RNA methyltransferase, three different sites are predicted. One is the catalytic core at the conserved K-D-K-E motif that includes catalytic residues D6928, K6968, and E7001 plus K6844. The second site surrounds the catalytic core and consists of Y6845, C6849, I6866, H6867, F6868, V6894, D6895, D6897, I6926, S6927, Y6930, and K6935. The third is located at the heterodimer interface. Ligands predicted to have high affinity for the first or second sites are reported. Three sites are also predicted for the nucleocapsid protein. This work uncovers key interactions that contribute to the function of the three viral proteins and also suggests alternative sites for ligand design.

Cardiac Arrest After Interscalene Block Before Arthroscopic Shoulder Surgery: A Case Report.

CASE: A 42-year-old previously healthy woman developed profound hypotension, bradycardia, and asystolic cardiac arrest requiring cardiopulmonary resuscitation after an interscalene block before being placed in the beach-chair position for shoulder arthroscopy. CONCLUSION: Activation of the Bezold-Jarisch reflex, a vagally mediated reflex leading to hypotensive bradycardic episodes, is a rare but devastating complication of shoulder arthroscopy when performed with the combination of interscalene blocks and the beach-chair position. Our case shows that the Bezold-Jarisch reflex may occur in patients before placement in the beach-chair position and may even lead to extreme reactions in healthy patients including asystolic cardiac arrest.

A rare presentation of sexsomnia in a military service member.

NONE: Sexsomnias are unconscious sexual behaviors during sleep (parasomnias) that are garnering more attention as they become increasingly evident in forensic cases. Presentations of sexsomnia in active duty service members are seldom described, and often evaluation is clouded by intoxication with substances such as alcohol, sleep deprivation, untreated sleep disturbances, or criminal behavior masquerading as a medical disorder. We present a case of a 40-year-old male soldier evaluated in our sleep clinic for multiple episodes of sleep masturbation occurring over a period of 2 years. The patient was concerned about his suitability for deployment to a combat zone and participation in field training exercises (both require sleeping in groups in an open environment). Video polysomnography confirmed moderate obstructive sleep apnea, and the patient showed improvement with continuous positive airway pressure therapy. The authors also discuss the relevance of this case compared with previously reported sexsomnia cases and expand on parasomnia topics that are more common in military populations.

Improved Functional Outcomes Following Operative Treatment of Midshaft Clavicle Fractures in an Active Duty Population.

Clavicle fractures are common orthopedic injuries that occur in a young active population and are even more common in the military. Military fitness test data presents the unique opportunity to analyze functional ability with regard to military-specific activities. The primary goal of this study was to compare functional outcomes using military fitness test data between operative and non-operative treatment of midshaft clavicle fractures.  We performed a retrospective review of active-duty U.S. Navy and Marine patients with midshaft clavicle fractures treated at our institution over a seven-year period. There were 94 and 153 patients in our operative and non-operative cohorts, respectively. Average follow-up time from the date of injury or surgery was 28 months. The rate of infection in the operative group (4%) was significantly greater than in the non-operative group (0%, p = 0.023). The rate of non-union in the operative group (3%) was significantly lower than in the non-operative group (14.5%, p = 0.004). The rate of symptomatic malunion in the operative group (0%) was significantly different from that in the non-operative group (4.6%, p = 0.036). There was no significant difference in the rate of revision surgery between the operative (9.2%) and non-operative (13.2%) groups (p = 0.105). A total of 51 marines met inclusion criteria for our functional outcome analysis using Marine Corps Physical Fitness Test (PFT) data. Of those who underwent operative fixation, 68% were able to meet or surpass their pre-injury average amount of pull-ups in their first PFT after surgery and 88% by the next PFT at least one year after surgery. While 69% of non-operative patients met their pre-injury average in their first PFT, only 57% maintained this level at least one year after surgery. This difference was statistically significant. In our functional outcome subgroup analysis, we found improved outcomes for pull-ups at least one year out when midshaft clavicle fractures are treated operatively compared to non-operatively. While similar findings in the literature are based on functional outcome questionnaires, physical fitness performance data has not been reported on to our knowledge.

Influence of type 1 diabetes on basal and agonist-induced permeability of the blood-brain barrier.

Type 1 diabetes mellitus (T1D) impairs endothelial nitric oxide synthase (eNOS)-dependent responses of cerebral arterioles. However, the influence of T1D on another critical aspect of endothelial cell function in the cerebral microcirculation, i.e., regulation of permeability of the blood-brain barrier (BBB), remains largely unknown. Our goal was to examine basal and agonist-induced changes in permeability of the BBB in nondiabetic and type 1 diabetic (streptozotocin; 50 mg/kg IP) rats. On the day of the experiment (2-3 months after streptozotocin), a craniotomy was made over the parietal cortex in nondiabetic and diabetic rats. We measured the permeability of the BBB (FITC-dextran-10K) under basal conditions and during application of histamine. We also measured diameter of cerebral arterioles in response to histamine in the absence and presence of NG-monomethyl-L-arginine (L-NMMA). We found that basal permeability of the BBB was elevated in T1D and application of histamine did not produce a further increase in permeability. In contrast, basal permeability of the BBB was minimal in nondiabetics and histamine produced an increase in permeability. In addition, histamine-induced arteriolar dilation was less in diabetics than in nondiabetics, and vasodilation to histamine was inhibited by L-NMMA. Our findings suggest that T1D-induced endothelial dysfunction leads to an increase in basal permeability of the BBB, but decreases the ability of the endothelium of the BBB to respond to an important inflammatory mediator. Thus, T1D impairs two critical aspects of endothelial cell function in the cerebral microcirculation, i.e., basal and agonist-induced changes in permeability of the BBB and arteriolar dilation.