Trans-seasonal activation of the neuroendocrine reproductive axis: Low-temperature winter dormancy modulates gonadotropin-releasing hormone neurons in garter snakes.

All animals use external cues from the environment to accurately time life-history events. How the brain decodes environmental stimuli to effect changes in physiology and behavior, however, is poorly understood, particularly with regard to supplementary environmental cues such as temperature. We asked if low-temperature dormancy alters the synthesis and/or release of gonadotropin-releasing hormone (GnRH). We used the well-studied red-sided garter snake (Thamnophis sirtalis) for this study, as low-temperature exposure is both necessary and sufficient to induce reproduction in northern populations of this species. Snakes were collected from the field and hibernated at 4°C or 10°C in complete darkness for up to 16 weeks. In males, increasing duration of low-temperature dormancy significantly increased GnRH-immunoreactive cell number and GnRH soma size (a proxy for relative cell activity) in the forebrain. These changes mirrored those in male reproductive behavior (reported previously) and plasma androgen concentrations. The changes in GnRH cell area observed in males were specific to the neuroendocrine population of cells in the medial preoptic area; soma size in the rostral GnRH cells did not change. Finally, temperature-induced changes in GnRH were sexually dimorphic: neither hibernation temperature nor the duration of winter dormancy significantly modulated GnRH cell number or soma size in females, despite the fact that plasma estradiol and corticosterone increased significantly in response to both. These data demonstrate that the neuroendocrine GnRH system is sensitive to environmental temperature and suggest that GnRH neurons play a conserved but trans-seasonal role in mediating changes in reproductive physiology and behavior in dissociated breeders.

Epidemiology of Pediatric Nonballistic Firearm Injuries to the Upper Extremity in the United States From 2000 to 2017.

Background: This study aimed to describe the epidemiology of pediatric upper extremity injury secondary to nonballistic firearms in the United States. Methods: The National Electronic Injury Surveillance Survey (NEISS) database was queried between 2000 and 2017 for injuries to the upper extremity from nonballistic firearms in patients aged ≤18 years. In total, 1502 unique cases were identified. Using input parameters intrinsic to the NEISS database, national weighted estimates were derived using Stata/IC 15.1 statistical software (StataCorp LLC, College Station, Texas), which yielded an estimate of 52 118 cases of nonballistic firearm trauma to the upper extremity who presented to US emergency departments over the study period. Descriptive statistics were performed using NEISS parameters. Results: An average of 2895 annual pediatric upper extremity nonballistic firearm injuries were identified between 2000 and 2017. Over 91% were sustained by men, and adolescents aged 12 to 18 were the most commonly injured (69.8%). Only 3.5% of all injuries required inpatient admission, and the most common sites of injury were the hand (41.1%), followed by fingers (35.9%). Conclusions: We conclude that nonballistic firearm injuries represent a significant burden of disease to adolescent men in the United States.

Utility of the Current Procedural Terminology Codes for Prophylactic Stabilization for Defining Metastatic Femur Disease.

INTRODUCTION: Cohorts from the electronic health record are often defined by the Current Procedural Terminology (CPT) codes. The error prevalence of CPT codes for patients receiving surgical treatment of metastatic disease of the femur has not been investigated, and the predictive value of coding ontologies to identify patients with metastatic disease of the femur has not been adequately discussed. METHODS: All surgical cases at a single academic tertiary institution from 2010 through 2015 involving prophylactic stabilization of the femur or fixation of a pathologic fracture of the femur were identified using the CPT and International Classification of Disease (ICD) codes. A detailed chart review was conducted to determine the procedure performed as documented in the surgical note and the patient diagnosis as documented in the pathology report, surgical note, and/or office visit notes. RESULTS: We identified 7 CPT code errors of 171 prophylactic operations (4.1%) and one error of 71 pathologic fracture fixation s(1.4%). Of the 164 prophylactic operations that were coded correctly, 87 (53.0%) had metastatic disease. Of the 70 pathologic operations that were coded correctly, 41 (58%) had metastatic disease. DISCUSSION: The error prevalence was low in both prophylactic stabilization and pathologic fixation groups (4.1% and 1%, respectively). The structured data (CPT and ICD-9 codes) had a positive predictive value for patients having metastatic disease of 53% for patients in the prophylactic stabilization group and 58% for patients in the pathologic fixation group. The CPT codes and ICD codes assessed in this analysis do provide a useful tool for defining a population in which a moderate proportion of individuals have metastatic disease in the femur at an academic medical center. However, verification is necessary.

The role of postoperative radiation and coordination of care in patients with metastatic bone disease of the appendicular skeleton.

Metastatic bone disease affects approximately 300,000 people in the United States, and the burden is rising. These patients experience significant morbidity and decreased survival. The management of these patients requires coordinated care among a multidisciplinary team of physicians, including orthopaedic surgeons. This article reviews the role of radiation therapy after orthopaedic stabilization of impending or realized pathologic extremity fractures. Orthopaedic surgeons have an opportunity to benefit patients with metastatic bone disease by referring them for consideration of post-operative radiation therapy. Further research into rates of referral and the effect on clinical outcomes in this population is needed.