Nationwide survey of medical student interest in and exposure to aerospace medicine.

Aerospace Medicine is experiencing a renaissance. Commercial spaceflight is now a reality, meaning that individuals with a variety of medical conditions will be flying in space. NASA has Mars plans, and SpaceX plans to send humans to Mars within the next decade, so today's medical students may be future physicians on these crews. Considering these developments, we evaluated interest in and exposure to Aerospace Medicine among medical students in the United States (US). A 19-question anonymous multiple-choice questionnaire was emailed to current medical students throughout the US. Information about demographics, career and research interests in aerospace medicine, opportunities available at students' respective institutions, and possible avenues for supporting students' interests was collected and analyzed. One thousand two hundred forty-four students (490 men, 751 women, 3 other) with a mean age of 25.8 ± 3.0 years from 60 institutions completed the questionnaire. Most respondents expressed an interest in learning about aerospace medicine during their training. A strong interest in research, as well as career opportunities, exists despite the majority of students reporting minimal access to opportunities to get involved in the field at most of the surveyed institutions. With growing interest and an expected increase in demand for physicians with a background in aerospace medicine, medical schools may be able to support students by increasing access to opportunities.

Pre-flight body weight effects on urinary calcium excretion in space.

Microgravity-induced bone loss increases urinary calcium excretion which increases kidney stone formation risk. Not all individuals show the same degree of increase in urinary calcium and some pre-flight characteristics may help identify individuals who may benefit from in-flight monitoring. In weightlessness the bone is unloaded, and the effect of this unloading may be greater for those who weigh more. We studied whether pre-flight body weight was associated with increased in-flight urinary calcium excretion using data from Skylab and the International Space Station (ISS). The study was reviewed and approved by the National Aeronautics and Space Administration (NASA) electronic Institutional Review Board (eIRB) and data were sourced from the Longitudinal Study of Astronaut Health (LSAH) database. The combined Skylab and ISS data included 45 participants (9 Skylab, 36 ISS). Both weight and day in flight were positively related to urinary calcium excretion. There was also an interaction between weight and day in flight with higher weight associated with higher calcium excretion earlier in the mission. This study shows that pre-flight weight is also a factor and could be included in the risk assessments for bone loss and kidney stone formation in space.

The Relationship Between the Timing of Knee Osteoarthritis Diagnoses and Arthroscopic Partial Meniscectomy.

BACKGROUND: There is ongoing debate regarding the efficacy of arthroscopic partial meniscectomy (APM) for meniscus tears in patients with knee osteoarthritis (OA). Some insurance payers will not authorize APM in patients with knee OA. The purpose of this study was to assess the timing of knee OA diagnoses in patients undergoing APM. METHODS: A large commercial national claims data set containing deidentified information from October 2016 to December 2020 was used to identify patients undergoing arthroscopic partial meniscectomy. Data were analyzed to determine whether patients in this group had a diagnosis of knee OA within 12 months before surgery and for the presence of a new diagnosis of knee OA at 3, 6, and 12 months after APM. RESULTS: Five lakhs thousand nine hundred twenty-two patients with a mean age of 54.0 ± 8.52 years, with the majority female (52.0%), were included. A total of 197,871 patients underwent APM without a diagnosis of knee OA at the time of the procedure. Of these patients, 109,427 (55.3%) had a previous diagnosis of knee OA within 12 months preceding surgery, and 24,536 (12.4%), 15,596 (7.9%), and 13,301 (6.7%) patients were diagnosed with knee OA at 3, 6, and 12 months after surgery, respectively. CONCLUSION: Despite evidence against APM in patients with knee OA, more than half of the patients (55.3%) had a previous diagnosis of OA within 12 months of surgery and 27.0% received a new diagnosis of knee OA within one year of surgery. A notable number of patients had a diagnosis of knee OA either before or shortly after APM.

Bone loss and kidney stone risk in weightlessness.

PURPOSE OF REVIEW: Weightlessness increases both bone loss and kidney stone formation risk. The large interior volume of the International Space Station (ISS) has allowed for a mix of exercise devices to help maintain the skeleton. But space exploration is changing. Long stays on the ISS will be replaced by journeys in smaller spacecraft both to and around the Moon. Small private space stations are under development. This will limit the ability to do exercise countermeasures, which can increase both bone loss and kidney stone risk. This review examines this risk and how it can be minimized in this new era of spaceflight. RECENT FINDINGS: Simple, low-mass, low-power ways to track bone loss and kidney stone risk in space are being researched. Tracking urinary calcium concentration in the first morning void and targeting additional countermeasures (e.g. bisphosphonates) to those who run consistently high levels is one promising approach. SUMMARY: New exploration spacecraft would not have the room and capability to replicate the current 2 h, daily exercise countermeasure programme on the ISS. A monitoring approach, perhaps using urinary calcium as a marker, is needed to find those at greatest risk. This would allow countermeasures to be targeted individually and used efficiently.

Tendon Transfers to Restore Shoulder Function for Obstetrical Brachial Plexus Palsy: A Systematic Review of the Literature.

BACKGROUND: Obstetrical brachial plexus palsy (OBPP) is a relatively common stretch injury of the brachial plexus sustained during delivery. Tendon transfers are commonly performed to improve shoulder function among patients with OBPP. Although several techniques for the surgical management of OBPP exist, it is unclear whether tendon transfers to the rotator cuff vs. posterior humerus yield different outcomes. METHODS: A systematic search in PubMed, Web of Science, the Cumulative Index to Nursing and Allied Health Literature, the Cochrane Library, and Google Scholar up to January 1, 2021, was performed. Relevant publications were classified by surgical technique of tendon transfers to the rotator cuff or posterior humerus. The standard mean difference (SMD) and 95% confidence intervals were calculated to compare preoperative and postoperative aggregate Mallet scores as well as abduction and external rotation scores using the Mallet scale. A p value of <0.01 was considered significant. RESULTS: Data from 26 studies and 951 patients (46.2% male patients) with a mean age of 68.9 ± 29.3 months were included. Eight hundred three patients underwent tendon transfer to the rotator cuff and 148 to the posterior humerus. The average postoperative follow-up period was 45.2 ± 21.7 months. The pooled cohort had an overall improvement in postoperative aggregate Mallet scores (SMD = 5.53, p < 0.001), abduction scores (SMD = 1.79, p < 0.001), and external rotation scores (SMD = 1.99, p < 0.001). Tendon transfer to the rotator cuff had a greater postoperative improvement in abduction (SMD = 1.90, p < 0.001) than transfer to the posterior humerus (SMD = 1.32, p < 0.001) while both techniques yielded similar improvements in external rotation (rotator cuff SMD = 2.01, p < 0.001, posterior humerus SMD = 1.98, p < 0.001). CONCLUSION: This is the first systematic review comparing outcomes for tendon transfers to the rotator cuff vs. the posterior humerus for improving shoulder function in patients with OBPP. Overall, tendon transfers are an effective treatment for improving shoulder function. Transfer of the latissimus dorsi and teres major to the rotator cuff compared with transfer to the posterior humerus results in greater improvement in abduction while both techniques have similar results in improving external rotation. LEVEL OF EVIDENCE: Level I Systematic review of Level I and Level II studies.

First Void Urinary Calcium for Tracking Bone Loss and Kidney Stone Risk in Space.

INTRODUCTION: Microgravity exposure unloads the skeleton. This increases urinary calcium excretion, which reflects both increased bone loss and kidney stone formation risk. We studied the probability that first morning void (FMV) urinary calcium (Uca) measurements would capture the highest Uca concentration in a day.METHODS: For 8 wk, three men and three women collected void-by-void 24-h urine samples weekly. Uca concentration was analyzed using a calcein-based system. Uca concentrations were ranked among all samples from each person. FMV and non-FMV (nFMV) Uca concentrations were compared with a Mann Whitney U-test. The probability that an FMV would capture the highest Uca concentration in a day was assessed.RESULTS: Among 377 voids collected, 46 were FMV and 331 were nFMV. Among all samples, the Uca concentration for FMV was significantly higher than nFMV (P < 0.0001). Out of the 46 FMVs, 24 were highest in Uca concentration for the corresponding 24-h period, giving a 52.2% probability that any given FMV would capture the highest Uca concentration in a day. The probability of measuring the highest Uca concentration from at least 1 d increased to 77.1%, and 89.1% when two or three FMVs were collected respectively.DISCUSSION: Acquiring 2-3 repeated FMVs provides a high likelihood of capturing the highest Uca from a day. This suggests repeated first morning void Uca concentrations could assess the risk of bone loss and kidney stone formation, which may provide ability for real-time implementation of countermeasure programs to prevent bone and renal complications in prolonged spaceflight.Thamer S, Buckey JC. First void urinary calcium for tracking bone loss and kidney stone risk in space. Aerosp Med Hum Perform. 2022; 93(7):546-550.

Sleep Apnea and Postoperative Medical Complications and Health Care Expenditures Following Open Reduction and Internal Fixation of Bimalleolar Ankle Fractures.

INTRODUCTION: Sleep Apnea (SA) is a common sleep disorder that increases postoperative morbidity. There is limited research on how SA influences outcomes following operative fixation of ankle fractures. Therefore, the aim of this study was to determine whether patients who undergo surgical fixation for bimalleolar ankle fractures have higher rates of medical complications and health care expenditures. METHODS: A retrospective review from January 1, 2005 to March 31, 2014 was conducted using the parts A and B Medicare Data from PearlDiver database. Patients with and without SA on the day of the primary open reduction and internal fixation (ORIF) of their bimalleolar ankle fractures were queried using the International Classification of Diseases, Ninth Revision codes. Welch'st-tests were used to compare costs of care. A multivariate binomial logistic regression model was used to calculate the odds ratio (OR) of adverse events. A P-value <.001 was considered statistically significant. RESULTS: There were 20 560 patients (SA = 3150; comparison cohort = 17 410) who underwent ORIF for bimalleolar ankle fractures during the study period. Sleep apnea patients were found to have significantly higher rates and odds of 90-day medical complications (21.42% vs 7.47%, OR: 3.11, P < .0001) and 90-day costs of care ($7213.12 vs $5415.79, P < .0001). CONCLUSION: This research demonstrates an increased risk of postoperative medical complications and health care costs among patients with SA undergoing ORIF for bimalleolar ankle fractures. LEVEL OF EVIDENCE: Therapeutic, Level IV: Retrospective.