Resolving the H I in damped Lyman α systems that power star formation.

Reservoirs of dense atomic gas (primarily hydrogen) contain approximately 90 per cent of the neutral gas at a redshift of 3, and contribute to between 2 and 3 per cent of the total baryons in the Universe1-4. These 'damped Lyman α systems'-so called because they absorb Lyman α photons within and from background sources-have been studied for decades, but only through absorption lines present in the spectra of background quasars and γ-ray bursts5-10. Such pencil beams do not constrain the physical extent of the systems. Here we report integral-field spectroscopy of a bright, gravitationally lensed galaxy at a redshift of 2.7 with two foreground damped Lyman α systems. These systems are greater than 238 kiloparsecs squared in extent, with column densities of neutral hydrogen varying by more than an order of magnitude on scales of less than 3 kiloparsecs. The mean column densities are between 1020.46 and 1020.84 centimetres squared and the total masses are greater than 5.5 × 108-1.4 × 109 times the mass of the Sun, showing that they contain the necessary fuel for the next generation of star formation, consistent with relatively massive, low-luminosity primeval galaxies at redshifts greater than 2.

A Posterior Acromial Bone Block Augmentation Is Biomechanically Effective at Restoring the Force Required To Translate the Humeral Head Posteriorly in a Cadaveric, Posterior Glenohumeral Instability Model.

PURPOSE: To assess the biomechanical utility of a posterior acromial bone block (PABB) for the treatment of posterior glenohumeral instability. METHODS: Ten fresh-frozen cadaveric specimens were obtained based upon an a priori power analysis. A 2.5-cm scapular spine autograft was harvested from all shoulders. A custom robot device was used to apply a 50-N compressive force to the glenohumeral joint. The humeral head was translated 10 mm posteroinferiorly at 30 degrees from the center of the glenoid at a rate of 1.0 mm/s in 6 consecutive conditions: (1) intact specimen, (2) intact with PABB, (3) posterior capsulolabral tear, (4) addition of the PABB, (5) removal of the PABB and repair of the capsulolabral tear (LR), and (6) addition of the PABB with LR. The maximum force required to obtain this translation was recorded. Paired t tests were performed to compare relevant testing conditions. RESULTS: Ten cadavers with a mean ± SD age of 54.4 ± 13.1 years and mean ± SD glenoid retroversion of 6.5 ± 1.0 degrees were studied. The PABB provided greater resistance force to humeral head translation compared to the instability state (instability, 29.3 ± 15.3 N vs PABB, 47.6 ± 21.0 N; P = .001; 95% confidence interval [CI], -27.6 to -10.0). When comparing PABB to LR, the PABB produced higher resistance force than LR alone (PABB, 47.6 ± 21.0 N; LR, 34.2 ± 20.5 N; P = .012; 95% CI, -23.4 to -4.1). An instability lesion treated with the PABB, with LR (P = .056; 95% CI, -0.30 to 20.4) or without LR (P = .351; 95% CI, -6.8 to 15.7), produced resistance forces similar to the intact specimen. CONCLUSIONS: A PABB is biomechanically effective at restoring the force required to translate the humeral head posteriorly in a cadaveric, posterior glenohumeral instability model. A posterior acromial bone block is a biomechanically feasible option to consider in patients with recurrent posterior instability. CLINICAL RELEVANCE: Augmentation of the posterior acromion may be a biomechanically feasible option to treat posterior shoulder instability.

Optimizing Safe Opioid Prescribing: A Paradigm Shift in Buprenorphine Management for Orthopaedic Surgery.

The worsening opioid epidemic in the United States, exacerbated by the COVID-19 pandemic, necessitates innovative approaches to pain management. Buprenorphine, a long-acting opioid, has gained popularity due to its safety profile and accessibility. Orthopaedic surgeons, encountering an increasing number of patients on buprenorphine, face challenges in perioperative management. This article will update orthopaedic surgeons on new developments in the understanding of buprenorphine as a pain reliever and share evidence-based practice guidelines for buprenorphine management. For patients on buprenorphine for opioid use disorder or chronic pain, the updated recommendation is to continue their home dose of buprenorphine through the perioperative period. The patient's buprenorphine prescriber should be contacted and notified of any impending surgery. The continuation of buprenorphine should be accompanied by a multimodal approach to analgesia, including a preoperative discussion about expectations of pain and pain control, regional anesthesia, standing acetaminophen, Nonsteroidal anti-inflammatory drugs when possible, gabapentinoids at night for patients under 65 years, cryotherapy, elevation, and early mobilization. Patients can also be prescribed short-acting, immediate-release opioids for breakthrough pain. Transdermal buprenorphine is emerging as an excellent option for the management of acute perioperative pain in both elective and nonelective orthopaedic patients. A single patch can provide a steady dose of pain medication for up to 1 week during the postoperative period. A patch delivery method can help combat patient nonadherence and ultimately provide better overall pain control. In the future, transdermal buprenorphine patches could be applied in virtually all fracture surgery, spinal surgery, total joint arthroplasty, ligament reconstructions with bony drilling, etc. As the stigma surrounding buprenorphine decreases, further opportunities for perioperative use may develop.

Risk factors for distal junctional failure in long-construct instrumentation for adult spinal deformity.

PURPOSE: The aim of this study is to identify risk factors associated with postoperative DJF in long constructs for ASD. METHODS: A retrospective review was performed at a tertiary referral spine centre from 01/01/2007 to 31/12/2016. Demographic, clinical and radiographic parameters were collated for patients with DJF in the postoperative period and compared to those without DJF. Survival analyses were performed using univariate logistic regression to identify variables with a p value < 0.05 for inclusion in multivariate analysis. Spearman's correlations were performed where applicable. RESULTS: One hundred two patients were identified. 41 (40.2%) suffered DJF in the postoperative period, with rod fracture being the most common sign of DJF (13/65; 20.0%). Mean time to failure was 32.4 months. On univariate analysis, pedicle subtraction osteotomy (p = 0.03), transforaminal lumbar interbody fusion (p < 0.001), pre-op LL (p < 0.01), pre-op SVA (p < 0.01), pre-op SS (p = 0.02), postop LL (p = 0.03), postop SVA (p = 0.01), postop PI/LL (p < 0.001), LL correction (p < 0.001), SVA correction (p < 0.001), PT correction (p = 0.03), PI/LL correction (p < 0.001), SS correction (p = 0.03) all proved significant. On multivariate analysis, pedicle subtraction osteotomy (OR 27.3; p = 0.03), postop SVA (p < 0.01) and LL correction (p = 0.02) remained statistically significant as independent risk factors for DJF. CONCLUSION: Recently, DJF has received recognition as its own entity due to a notable postoperative incidence. Few studies to date have evaluated risk factors for DJF. The results of our study highlight that pedicle subtraction osteotomy, poor correction of lumbar lordosis, and sagittal vertical axis are significantly associated with postoperative occurrence of DJF.

Male Youth Ice Hockey Concussion Incidence in a USA Hockey Membership-Adjusted Population: A Peak in 2011 and the Impact of Major Rule Changes.

OBJECTIVE: To investigate the incidence of youth ice hockey-related concussions preceding and following the implementation of new body-checking and head contact rules by USA hockey in 2011. We hypothesized a decrease in concussions after the rule change. DESIGN: Retrospective analysis. SETTING: United States emergency department (ED) data queried in the National Electronic InjurySurveillance System (NEISS). PATIENTS: National Electronic Injury Surveillance System reported male youth (≤18 years) ice hockey concussion cases from January 1, 2002, to December 31, 2016. In total, 848 players were diagnosed with concussion, representing a national estimate of 17 374 cases. INDEPENDENT VARIABLES: Time, specifically years. MAIN OUTCOME MEASURES: Incidences and incidence rates (measured per 10 000 person-years) of male youth ice hockey concussions. Annual trends were analyzed using descriptive and linear or polynomial regression analysis. RESULTS: The national estimate of youth ice hockey-related concussions seen in US emergency departments (EDs) increased significantly from 656 in 2007 to 2042 in 2011 (P < 0.01). During the same period, their respective incidence increased significantly from 21.8 to 66.8 per 10 000, before dropping through 2016 (P < 0.05). After 2011, concussions decreased from 1965 in 2012 to 1292 in 2016 (P = 0.055). The gap in concussion incidence between the 11 to 12 and 13 to 14 divisions widened after 2011 (before 2011: 41 vs 49 per 10 000 person-years [P = 0.80]; after 2011: 45 and 89, respectively [P < 0.01]). CONCLUSIONS: US EDs experienced a significant increase in youth ice hockey concussion visits from 2007 to 2011. After the 2011 rule changes, concussion visits decreased significantly from 2012 to 2016.

A giant protogalactic disk linked to the cosmic web.

The specifics of how galaxies form from, and are fuelled by, gas from the intergalactic medium remain uncertain. Hydrodynamic simulations suggest that 'cold accretion flows'--relatively cool (temperatures of the order of 10(4) kelvin), unshocked gas streaming along filaments of the cosmic web into dark-matter halos--are important. These flows are thought to deposit gas and angular momentum into the circumgalactic medium, creating disk- or ring-like structures that eventually coalesce into galaxies that form at filamentary intersections. Recently, a large and luminous filament, consistent with such a cold accretion flow, was discovered near the quasi-stellar object QSO UM287 at redshift 2.279 using narrow-band imaging. Unfortunately, imaging is not sufficient to constrain the physical characteristics of the filament, to determine its kinematics, to explain how it is linked to nearby sources, or to account for its unusual brightness, more than a factor of ten above what is expected for a filament. Here we report a two-dimensional spectroscopic investigation of the emitting structure. We find that the brightest emission region is an extended rotating hydrogen disk with a velocity profile that is characteristic of gas in a dark-matter halo with a mass of 10(13) solar masses. This giant protogalactic disk appears to be connected to a quiescent filament that may extend beyond the virial radius of the halo. The geometry is strongly suggestive of a cold accretion flow.

Surgical Decision Making for Thoracolumbar Spine Injuries in Polytrauma Patients.

The management of thoracolumbar spine injuries in patients with multiple traumatic injuries is a challenge complicated by multiple competing medical and surgical demands. Safe and effective treatment of polytrauma patients with a thoracolumbar spine injury requires a multidisciplinary approach that involves surgical and critical care teams. The Thoracolumbar Injury Classification and Severity Score, which was developed to facilitate consistent surgical decision making in patients with a thoracolumbar spine injury, provides objective criteria for the classification and management of thoracolumbar spine injuries. The AOSpine study group recently developed a comprehensive thoracolumbar injury classification system that was subsequently used to create the Thoracolumbar AOSpine Injury Score, which helps guide thoracolumbar spine injury management via objective criteria. These scoring systems have been effectively used in clinical practice and allow for a focused and objective assessment of thoracolumbar spine injuries. Both the Thoracolumbar Injury Classification and Severity Score and the Thoracolumbar AOSpine Injury Score should be routinely used in treatment decision making to optimize outcomes and avoid unnecessary surgical treatment in polytrauma patients with a thoracolumbar spine injury.

Fracture Risk in Ulnohumeral Arthroplasty-A Biomechanical Study.

PURPOSE: Ulnohumeral arthroplasty, also known as the Outerbridge-Kashiwagi procedure, was popularized after reports of successful results in 1978, and has long been a means of management for ulnohumeral arthritis. However, there are concerns over the loss of integrity of the distal humerus as a result of fenestration. The purpose of this study was to examine the relationship between the size of fenestration and fracture risk. METHODS: Using a validated fourth-generation sawbones model, load to failure and site of fracture were investigated following incrementally increasing distal humeral fenestration sizes. Each sample was subjected to a uniform extension stress on a materials testing system, with 5 samples run for each group. The experimental groups began with a fenestration size of 10 mm and increased by 3 mm increments up to 31 mm. Load at failure and site of fracture were recorded for each sample. RESULTS: Forty-five fourth-generation sawbones samples were tested. Average load at sample failure was equivalent for each fenestration group up to 25 mm. At 28 mm, average load to failure began to decrease, and was statistically significant beginning between 28 mm and 31 mm. At 28 mm, 4 of 5 samples fractured through the fenestration, and at 31 mm, all 5 samples fractured through the fenestration. This change in fracture site became statistically significant between 25 mm and 28 mm. CONCLUSIONS: Distal humeral fenestration does compromise its structural integrity; however, for resection in the range of 10-25 mm, there is no increased risk of fracture. CLINICAL RELEVANCE: On the basis of this biomechanical model, the authors do not recommend any activity limitations after initial surgical recovery, but do recommend against distal humeral fenestrations larger than 25 mm when performing this procedure.

A novel method of standardized myocardial infarction in aged rabbits.

The incidence of both myocardial infarction (MI) and sudden cardiac death increases with age. Here, we describe the development of a minimally invasive large animal model of MI that can be applied to young or aged animals. We demonstrate that rabbit coronary anatomy is highly variable, more so than described in previous literature. In this work, we categorize the coronary pattern of 37 young rabbits and 64 aged rabbits. Aged rabbits had a higher degree of branching from the left main coronary artery. Standardizing the model across age cohorts required a new approach, targeting an area of myocardium rather than a specific vessel. Here, we present a method for achieving a reproducible infarct size, one that yielded a consistent scar encompassing ~30% of the apical left ventricular free wall. The model's consistency allowed for more valid comparisons of MI sequelae between age cohorts.NEW & NOTEWORTHY This study describes the coronary angiographic imaging of young and aged rabbits. We developed and improved a novel minimally invasive approach for coil embolization that targets a specific area of myocardium and yielded a consistent scar encompassing ~30% of the left ventricular free wall of young and aged rabbit hearts.

An Update on Emerging Techniques and Considerations in Revision Anterior Cruciate Ligament Reconstruction.

¼ The rate of primary anterior cruciate ligament reconstruction (ACLR) failure in at-risk populations remains unacceptably high and necessitates thorough evaluation of native alignment and concomitant injuries.¼ Posterior tibial slope of >12° is a substantial risk factor of ACLR failure and should be corrected through anterior closing wedge osteotomy.¼ Varus malalignment of >5° exacerbates stress on the ACL graft, increases ACLR failure risks, and should be considered for correction through high tibial osteotomy at the time of revision ACLR.¼ Injuries to the anterolateral ligamentous complex are prevalent in ACL ruptures, and high-risk patients have shown benefit from anterolateral ligament reconstruction or lateral extra-articular tenodesis in the revision setting.¼ Addressing posterolateral corner, collateral ligament, and meniscal injuries, during revision ACLR, is vital to mitigate increased graft forces and optimize knee stability and functional outcomes.

Cervical Disc Displacement in Military Pilots.

INTRODUCTION: Cervical disc displacement (CDD) may disqualify pilots from flying and have a profound impact on military unit capability. The objective of this retrospective database review is to characterize the incidence and demographic predictors of symptomatic cervical spine disc displacement in pilots of fixed- and rotary-wing aircraft and ground-based controls. MATERIALS AND METHODS: The Defense Military Epidemiology Database was queried for first-occurrence ICD-9 code 722.0: CDD cases from 2007 to 2015. Injury count rates among aircraft groups and overall incidence per 1,000 person-years were calculated and standardized for age, gender, and military rank, and 95% confidence intervals (CIs) were compared to determine significance. RESULTS: There were 934 new cases of CDD among active duty U.S. Military pilots during the study period. The overall incidence of CDD in all pilots during this time frame was 2.715 per 1,000 person-years (95% CI, 2.603-2.830). Helicopter pilots had a significantly higher incidence compared to all other aircraft pilots and crew at 3.79 per 1,000 person-years (95% CI, 3.48-4.13). This finding remained statistically significant after standardizing for age, gender, and rank. Among all military officers, increasing age was a risk factor for CDD. CONCLUSIONS: The U.S. Military helicopter pilots have an increased risk compared to fixed-wing pilots and non-pilot controls. CDD remains a rare, though career-threatening, condition. Increased education and awareness training are warranted for both helicopter pilots and flight physicians to recognize signs and symptoms of cervical pathology. Continued investigations into preventive measures to minimize injury and time unfit for flight are warranted.

Femoral shaft displacement and Winquist classification provide predictive characteristics for combined femoral neck and femoral shaft fractures.

OBJECTIVES: The goal of this study is to establish radiographic features and characteristics of patient injury in cases of femoral shaft fractures that predict the presence of ipsilateral femoral neck fractures (IFNFs). METHODS: Patient data was retrospectively assessed from a single level I trauma center through the electronic health record using (Current Procedural Terminology) CPT codes for both isolated and combined ipsilateral femoral shaft and neck fractures. Demographic information, injury characteristics, and independently reviewed radiographic features were collected and compared against the same information from a group of isolated femoral shaft fractures. Multivariable logistic regression was performed to identify risk factors for concomitant IFNFs and their respective odds ratios. A probability algorithm for assessing ipsilateral femoral neck fractures based on independent multivariate predictors was constructed and used. RESULTS: A total of 113 patients with either isolated femoral shaft fractures or combined femoral shaft and IFNF (n = 33) met inclusion criteria and were identified for this study. Fracture displacement was most strongly associated with increased risk of combined injury with an aOR of 25.64 (95 %CI = 5.96-110.28) for every 100 % displacement. Motorcycle crash (MCC) was the mechanism associated with the highest risk of combined injury, with an aOR of 9.85 (95 % CI = 1.99-48.74). Combined injury was also correlated with lower Winquist score and presentation with a closed fracture, with aORs of 0.38 (95 %CI = 0.21 - 0.68) and 11.61 (95 %CI = 1.93-69.94), respectively. Presence of at least 3 of the statistically significant variables produced a positive predictive value (PPV) of ≥ 89 % for combined femoral shaft and IFNF. CONCLUSIONS: Identification of combined femoral shaft and IFNF is of critical importance when caring for orthopedic trauma patients. While diagnosis remains a challenging task, MCC mechanism, >100 % fracture displacement, and lower Winquist classification were found to be associated with combined injuries. The combination of these variables might assist in predicting the probability of combined injury and potentially guide decision making on the appropriateness of obtaining single sequence MRI or implementing prophylactic femoral neck fixation. LEVEL OF EVIDENCE: Level III.

A turbulent wake as a tracer of 30,000 years of Mira's mass loss history.

Mira is one of the first variable stars ever discovered and it is the prototype (and also the nearest example) of a class of low-to-intermediate-mass stars in the late stages of stellar evolution. These stars are relatively common and they return a large fraction of their original mass to the interstellar medium (ISM) (ref. 2) through a processed, dusty, molecular wind. Thus stars in Mira's stage of evolution have a direct impact on subsequent star and planet formation in their host galaxy. Previously, the only direct observation of the interaction between Mira-type stellar winds and the ISM was in the infrared. Here we report the discovery of an ultraviolet-emitting bow shock and turbulent wake extending over 2 degrees on the sky, arising from Mira's large space velocity and the interaction between its wind and the ISM. The wake is visible only in the far ultraviolet and is consistent with an unusual emission mechanism whereby molecular hydrogen is excited by turbulent mixing of cool molecular gas and shock-heated gas. This wind wake is a tracer of the past 30,000 years of Mira's mass-loss history and provides an excellent laboratory for studying turbulent stellar wind-ISM interactions.

Role of Quadriceps Tendon Autograft in Primary and Revision Anterior Cruciate Ligament Reconstruction.

¼ The quadriceps tendon (QT) autograft is becoming increasingly popular in both primary and revision anterior cruciate ligament reconstruction (ACLR).¼ The biomechanical properties of the QT are similar to those of the native ACL, the hamstring tendon (HT), and bone-patellar tendon-bone (BTB) autografts.¼ QT autograft allows surgeons to be flexible with their graft size and reconstruction technique.¼ The QT autograft performs in a similar fashion to the BTB and HT autografts, with excellent patient-reported outcomes, consistent postoperative knee stability, and low rates of postoperative complications including graft failure and donor site morbidity.¼ There are emerging data that the QT autograft is a viable option in revision ACLR.

Local anesthetic with monitored anesthesia care in cephalomedullary nailing of proximal femur fractures.

INTRODUCTION: Proximal femur fractures have high rates of morbidity, mortality, and perioperative complications. Limiting anesthesia, especially in the elderly population, is a priority from a medical perspective. The goal of the current study is to present a technique of using local anesthetic with monitored anesthesia care (MAC) for the fixation of intertrochanteric (IT) femur fractures with cephalomedullary nailing (CMN), provide early clinical results in a small series of patients, and evaluate the safety, efficiency, and anesthetic efficacy of our technique. HYPOTHESIS: The use of only local anesthetic with MAC for the fixation of IT fractures is safe and leads to decreased operative times when compared to spinal and general anesthesia. MATERIALS AND METHODS: Patients undergoing cephalomedullary nailing (CMN) with a long nail for IT femur fractures by a single surgeon from January 2020 to June 2021 were identified retrospectively from a prospectively-collected patient registry. Patient demographics, operative time, length of hospital stay, perioperative medication use, and complications were collected. Analysis of variance, Chi2, linear regression, and two-sampled T-tests were performed to analyze potential differences between the local anesthesia group and the general or spinal anesthesia group. RESULTS: Thirty-seven patients were identified. Eleven patients underwent CMN using local anesthesia with MAC, 11 using spinal anesthesia, and 15 using general anesthesia. The local anesthesia group demonstrated significantly lower operating room times and anesthesia induction to incision time compared to other anesthesia techniques. The local anesthesia group also trended towards less need for vasopressors during surgery and less postoperative delirium. No differences were identified in intraoperative narcotic use, complications, patient mortality, or hospital readmissions. CONCLUSIONS: Local anesthesia with MAC for the treatment of IT fractures with CMN was associated with decreased operating room times and had similar complication rates including blood transfusions, readmissions, and mortalities, when compared to spinal and general anesthesia. LEVEL OF EVIDENCE: III, therapeutic.

Association of Emergency Department Evaluation With Public Insurance Use and Treatment Delays for ACL Injury.

Background: Utilization of an emergency department (ED) visit for anterior cruciate ligament (ACL) injury is associated with high cost and diagnostic unreliability. Hypothesis: Patients initially evaluated at an ED for an ACL injury would be more likely to be from a lower income quartile, use public insurance, and experience a delay in treatment. Study Design: Cohort study; Level of evidence, 3. Methods: Patients in the Rhode Island All Payers Claims Database who underwent ACL reconstruction (ACLR) between 2012 and 2021 were identified using the Current Procedure Terminology (CPT) code 29888. Patients were stratified into 2 cohorts based on CPT codes for ED or in-office services within 1 year of ACLR. A chi-square analysis was used to test for differences between cohorts in patient and surgical characteristics. Multivariable linear and logistic regression were used to determine how ED evaluation affected timing and outcome variables. Results: While adjusting for patient and operative characteristics, patients in the ED cohort were more likely to have Medicaid (29% vs 12.5%; P < .001) and be in the lowest income quartile (44.6% vs 32.1%; P < .001). ED visit and Medicaid status were associated with increased time to (1) diagnostic magnetic resonance imaging, adding 7.97 days on average (95% CI, 4.14-11.79 days; P < .001) and 8.40 days (95% CI, 3.44-13.37 days; P = .001), respectively; and (2) surgery, adding 20.30 days (95% CI, 14.10-26.49 days; P < .001) and 12.88 days (95% CI, 5.15-20.60 days; P = .001), respectively. Patients >40 years who were evaluated in the ED were 2.5 times more likely to require subsequent ACLR (odds ratio, 2.50 [95% CI, 1.01-6.21]; P = .049). Conclusion: In this study, patients who visited the ED within 1 year before ACLR were more likely to have a lower income, public insurance, increased time to diagnostic imaging, and increased time to surgery, as well as decreased postoperative physical therapy use and increased subsequent ACLR rates in the 40-49 years age-group.

Short-term outcomes following open gluteus maximus transfer for the management of hip abductor tears.

Tears of the gluteus medius and minimus are an important cause of recalcitrant greater trochanteric pain syndrome. Although endoscopic and open abductor repairs have demonstrated promising outcomes, the success of these techniques is dependent on the size of the tear and the quality of the tissue. In patients presenting with abductor insufficiency and evidence of previous repair failure, large retracted tears, muscle atrophy and/or fatty infiltration, reconstruction/augmentation techniques should be considered. In the present study, we present a retrospective cohort study assessing patient outcomes following open gluteus maximus transfer for irreparable or severely retracted gluteus medius tears. Patients were included in the present study if they underwent open gluteus maximus transfer to address hip abductor tears that a senior surgeon deemed irreparable or at high risk for failure following isolated repair secondary to the following tear characteristics: large tears with >2 cm of retraction, the presence of extensive fatty infiltration (Goutallier Grade 3 or greater) and/or patients requiring revision abductor repair due to primary repair failure with associated pain and a Trendelenburg gait. Patients undergoing a concomitant, or those with a previous history of hip arthroplasty, were excluded from the study. All participants were prospectively enrolled in the study, and both pre- and post-operative patient-reported outcomes were collected at 6 months and 1 year including the modified Hip Harris Score, Visual Analog Score, Hip Outcomes Score of Activities Daily Living, Hip Outcomes Score for Sports-Related Activities and Overall Satisfaction with Hip. Pre-operative scores were compared with post-operative assessments using Student's t-test with a significance level of P < 0.05. Twenty-one patients and 22 hips were included. The average age was 69 (SD ±9.2) and 17 (81%) were females. The average body mass index was 30.0 (±6.2). The outcome scores at both 6 months and 1 year demonstrated significant improvements compared with pre-operative functional assessment. This article reports the utility of gluteus medius/minimus repair augmentation or reconstruction via gluteus maximus transfer demonstrating improvement in patient-reported outcomes at short-term follow-up.

Suppression of star formation in early-type galaxies by feedback from supermassive black holes.

Detailed high-resolution observations of the innermost regions of nearby galaxies have revealed the presence of supermassive black holes. These black holes may interact with their host galaxies by means of 'feedback' in the form of energy and material jets; this feedback affects the evolution of the host and gives rise to observed relations between the black hole and the host. Here we report observations of the ultraviolet emissions of massive early-type galaxies. We derive an empirical relation for a critical black-hole mass (as a function of velocity dispersion) above which the outflows from these black holes suppress star formation in their hosts by heating and expelling all available cold gas. Supermassive black holes are negligible in mass compared to their hosts but nevertheless seem to play a critical role in the star formation history of galaxies.

Delta-doped electron-multiplied CCD with absolute quantum efficiency over 50% in the near to far ultraviolet range for single photon counting applications.

We have used molecular beam epitaxy (MBE) based delta-doping technology to demonstrate nearly 100% internal quantum efficiency (QE) on silicon electron-multiplied charge-coupled devices (EMCCDs) for single photon counting detection applications. We used atomic layer deposition (ALD) for antireflection (AR) coatings and achieved atomic-scale control over the interfaces and thin film materials parameters. By combining the precision control of MBE and ALD, we have demonstrated more than 50% external QE in the far and near ultraviolet in megapixel arrays. We have demonstrated that other important device performance parameters such as dark current are unchanged after these processes. In this paper, we briefly review ultraviolet detection, report on these results, and briefly discuss the techniques and processes employed.

Indicators for Substantial Neurological Recovery Following Elective Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The purposes of this study were to determine the rate of improvement of significant preoperative weakness, identify risk factors for failure to improve, and characterize the motor recovery of individual motor groups. SUMMARY OF BACKGROUND DATA: While neck and arm pain reliably improve following anterior cervical discectomy and fusion (ACDF), the frequency and magnitude of motor recovery following ACDF remain unclear. METHODS: We performed a retrospective review of patients undergoing 1-4-level ACDF at a single institution between September 2015 and June 2016. Patients were subdivided into 2 groups based upon the presence or absence of significant preoperative weakness, which was defined as a motor grade <4 in any single upper extremity muscle group. Clinical notes were reviewed to determine affected muscle groups, rates of motor recovery, and risk factors for failure to improve. RESULTS: We identified 618 patients for inclusion. Significant preoperative upper extremity weakness was present in 27 patients (4.4%). Postoperatively, 19 of the affected patients (70.3%) experienced complete strength recovery, and 5 patients (18.5%) experienced an improvement in muscle strength to a motor grade ≥4. The rate of motor recovery postoperatively was 85.7% in the triceps, 83.3% in the finger flexors, 83.3% in the hand intrinsics, 50.0% in the biceps, and 25.0% in the deltoids. Risk factors for failure to experience significant motor improvement were the presence of myelomalacia (odds ratio: 28.9, P <0.01) and the performance of >2 levels of ACDF (odds ratio: 10.1, P <0.01). CONCLUSIONS: Patients with substantial preoperative upper extremity weakness can expect high rates of motor recovery following ACDF, though patients with deltoid weakness, myelomalacia, and >2 levels of ACDF are less likely to experience significant motor improvement.