Prevalence and risk factors of occupational neck pain in Chinese male fighter pilots: a cross-sectional study based on questionnaire and cervical sagittal alignment.

Background: Neck pain (NP) is a common musculoskeletal disorder among fighter pilots and has become a rising concern due to its detrimental impact on military combat effectiveness. The occurrence of NP is influenced by a variety of factors, but less attention has been paid to the association of NP with demographic, occupational, and cervical sagittal characteristics in this group. This study aimed to investigate the prevalence and risk factors of NP in Chinese male fighter pilots using a questionnaire and cervical sagittal measurements. Methods: Demographic and flight-related data, as well as musculoskeletal pain information, were gathered from Chinese male fighter pilots via a self-report questionnaire. Cervical sagittal parameters were measured and subtypes were classified using standardized lateral cervical radiographs. Differences in various factors between the case and control groups were analyzed using t-tests or chi-square tests. Binary logistic regressions were conducted to explore potential risk factors contributing to NP. Predictors were presented as crude odds ratios (CORs) and adjusted odds ratios (AORs), along with their respective 95% confidence intervals (CIs). Results: A total of 185 male fighter pilots were included in this cross-sectional study. Among them, 96 (51.9%) reported experiencing NP within the previous 12 months. The multivariate regression analysis revealed that continuous flight training (AOR: 4.695, 95% CI: 2.226-9.901, p < 0.001), shoulder pain (AOR: 11.891, 95% CI: 4.671-30.268, p < 0.001), and low back pain (AOR: 3.452, 95% CI: 1.600-7.446, p = 0.002) were significantly associated with NP. Conclusion: The high 12-month prevalence of NP among Chinese male fighter pilots confirms the existence of this growing problem. Continuous flight training, shoulder pain, and low back pain have significant negative effects on pilots' neck health. Effective strategies are necessary to establish appropriate training schedules to reduce NP, and a more holistic perspective on musculoskeletal protection is needed. Given that spinal integrated balance and compensatory mechanisms may maintain individuals in a subclinical state, predicting the incidence of NP in fighter pilots based solely on sagittal characteristics in the cervical region may be inadequate.

Aviation Decompression Sickness in Aerospace and Hyperbaric Medicine.

INTRODUCTION: The U.S. Navy experienced a series of physiological events in aircrew involving primarily the F/A-18 airframe related to rapid decompression of cabin pressures, of which aviation decompression sickness (DCS) was felt to contribute. The underlying pathophysiology of aviation DCS is the same as that of diving-related. However, based on the innate multifactorial circumstances surrounding hypobaric DCS, in clinical practice it continues to be unpredictable and less familiar as it falls at the intersect of aerospace and hyperbaric medicine. This retrospective study aimed to review the case series diagnosed as aviation DCS in a collaborative effort between aerospace specialists and hyperbaricists to increase appropriate identification and treatment of hypobaric DCS.METHODS: We identified 18 cases involving high-performance aircraft emergently treated as aviation DCS at a civilian hyperbaric chamber. Four reviewers with dual training in aviation and hyperbaric medicine retrospectively reviewed cases and categorized presentations as "DCS" or "Alternative Diagnosis".RESULTS: Reviewers identified over half of presenting cases could be attributed to an alternative diagnosis. In events that occurred at flight altitudes below 17,000 ft (5182 m) or with rapid decompression pressure changes under 0.3 atm, DCS was less likely to be the etiology of the presenting symptoms.CONCLUSIONS: Aviation physiological events continue to be difficult to diagnose. This study aimed to better understand this phenomenon and provide additional insight and key characteristics for both flight physicians and hyperbaric physicians. As human exploration continues to challenge the limits of sustainable physiology, the incidence of aerospace DCS may increase and underscores our need to recognize and appropriately treat it.Kutz CJ, Kirby IJ, Grover IR, Tanaka HL. Aviation decompression sickness in aerospace and hyperbaric medicine. Aerosp Med Hum Perform. 2023; 94(1):11-17.

Exceptional survival of an airplane stowaway, treated successfully with hyperbaric oxygen.

Survival of airplane stowaways is rare. Here we report an exceptional case of successful treatment and full recovery. After a transcontinental flight an unconscious stowaway was discovered in a wheel well of a Boeing 747-400F. Airport paramedics confirmed regular respiration and achieved 100% oxygen saturation (pulse oximetry) by high-flow oxygen. Rectal body temperature was 35.5 °C. On arrival at the emergency department, the patient's vital signs were stable. He did not respond to verbal stimuli. He localized to painful stimuli with both arms, however, there was no reaction to stimuli to both legs. We suspected his neurological deficits were caused by posthypoxic encephalopathy or altitude decompression sickness (DCS), the latter amenable to hyperbaric oxygen therapy (HBOT). HBOT was performed for 5 h (US Navy Treatment Table 6) and afterwards, full neurological recovery was documented. About 24 h after admission a new proximal paresis of the left leg was noted. Assuming recurrence of DCS, daily HBOT was scheduled for three days, after which motor function had again returned to normal. Stowaways travelling in airplane wheel wells experience extreme environmental circumstances. The presented patient survived an eight-hour exposure to calculated barometric pressures as low as 190 mmHg and ambient PO2 of 40 mmHg. Apart from creating awareness of this rare patient category, we want to stress the risk of altitude DCS in unpressurized flights. When DCS is suspected, immediate high-flow oxygen therapy should be initiated, followed by HBOT at the earliest opportunity.

A Novel Biopsychosocial Approach to Neck Pain in Military Helicopter Aircrew.

INTRODUCTION: Flight-related neck pain (FRNP) is a frequently reported musculoskeletal complaint among military helicopter aircrew. However, despite its prevalence and suspected causes, little is known of the underpinning pain mechanisms or the impact of neck pain on aircrews in-flight task performance. The biopsychosocial (BPS) approach to health, combined with the contemporary conceptualization of musculoskeletal pain, in which injury and pain are not necessarily synonymous, provides a relatively new holistic framework within which to consider the problem of FRNP in military helicopter aircrew. Combining these concepts, a new conceptual model is proposed to illustrate how biopsychosocial factors may influence pain perception, potentially affecting aircrews capacity to process information and, therefore, threatening in-flight task performance. Recommendations are made for considering the underlying pain mechanisms of FRNP to aid prognoses and guide the development of holistic evidence-based countermeasures for FRNP in military helicopter aircrew. Development of instruments able to measure psychosocial factors, such as self-efficacy and functional ability, validated in the military helicopter aircrew population, would assist this task.Vail RE, Harridge SDR, Hodkinson PD, Green NDC, Pavlou M. A novel biopsychosocial approach to neck pain in military helicopter aircrew. Aerosp Med Hum Perform. 2021; 92(5):333341.

Medicine in Extreme Environments: A New Medical Student Elective Class for Wilderness, Aerospace, Hyperbaric, Exercise, and Combat Medicine.

We developed an elective course titled Medicine in Extreme Environments (MEE) at the University of Texas Southwestern Medical Center for first- and second-year medical students. This course covered physiology, research, clinical practice, and career guidance regarding the fields of wilderness, space, hyperbaric, combat, and exercise medicine. The primary aim was to generate interest in and awareness of these seldom covered fields of medicine by exposing medical students to these disciplines during their preclinical years. A postcourse questionnaire was implemented to investigate whether the MEE course increased awareness of, interest in, and knowledge in the fields of medicine included in the curriculum. Through 2 iterations of the class, a total of 67 students enrolled in the course, and 38 students completed the questionnaire. After course completion, 95% felt they better understood the work and lifestyle of the fields covered, 100% learned more about concepts of each field, and 74% agreed that the elective influenced the direction of their future careers to include some part of the fields emphasized. Although only a limited number of students enrolled in this course, these initial findings suggest that the MEE curriculum may have some utility in promoting awareness of and interest in these medical disciplines among students who attend the course. With continued student and faculty support, this course will likely be continued annually at our institution. We believe that certain aspects of this course may be useful in helping develop similar courses at other medical schools.

High-Altitude Decompression Sickness Treated with Hyperbaric Therapy and Extracorporeal Oxygenation.

BACKGROUND: High-altitude decompression sickness (HADCS) is a rare condition that has been associated with aircraft accidents. To the best of our knowledge, the present paper is the first case report of a patient treated for severe HADCS using recompression therapy and veno-venous extracorporeal oxygenation (VV-ECMO) with a complete recovery.CASE REPORT: After depressurization of a cabin, the 51-yr-old jet pilot was admitted to the Military Institute of Medicine with a life-threatening HADCS approximately 6 h after landing from a high-altitude flight, in a dynamically deteriorating condition, with progressing dyspnea and edema, reporting increasing limb paresthesia, fluctuating consciousness, and right-sided paresis. Hyperbaric oxygen therapy in the intensive care mode was initiated. A therapeutic recompression with U.S. Navy Treatment Table 6 was performed with neurological improvement. Due to cardiovascular collapse, sedation, mechanical ventilation, and significant doses of catecholamines were started, followed by continuous veno-venous hemodialysis. In the face of disturbances in oxygenation, during the second day of treatment the patient was commenced on veno-venous extracorporeal oxygenation. Over the next 6 d, the patient's condition slowly improved. On day 7, VV-ECMO was discontinued. On day 19, the patient was discharged with no neurological deficits.DISCUSSION: We observed two distinct stages during the acute phase of the disease. During the first stage, signs of hypoperfusion, neurological symptoms, and marbled skin were observed. During the second stage, multiple organ dysfunction dominated, including heart failure, pulmonary edema, acute kidney injury, and fluid overload, all of which can be attributed to extensive endothelial damage.Siewiera J, Szalanski P, Tomaszewski D, Kot J. High-altitude decompression sickness treated with hyperbaric therapy and extracorporeal oxygenation. Aerosp Med Hum Perform. 2020; 91(2):106-109.

High Altitude Performance of Loudspeakers and Potential Impact on Audiometric Findings.

BACKGROUND: The evaluation of how air rarefaction can affect a loudspeaker performance at altitude implies the need for characterization of earphones during hypobaric conditions. The aim of this study was phonometric analysis at different altitudes of the acoustic output of a widely used earphone model, along with its consequences on audiological investigations conducted under such environmental conditions.METHODS: The transfer function of a TDH-39P earphone was analyzed with an artificial ear under nine different altitude levels, from sea level up to 35,000 ft, inside a hypobaric chamber. A specific phonometric system not sensitive to environmental pressure changes was used. Other potentially confounding factors, such as environmental temperature and humidity, were continuously monitored.RESULTS: No relevant temperature or humidity changes were detected. The sound pressure level generated by the earphone under hypobaric conditions was found considerably affected by air density changes. These data produced a correction table aiming at recalibrating the earphone's output at each audiometric octave test frequency within the 250-8000 Hz range. Quite different characteristics of response were observed at different audiometric frequencies. Such findings were particularly evident for altitudes exceeding 12,000 ft.DISCUSSION: The development of a frequency-selective and altitude-related correction factor for acoustic stimuli is an essential aspect when hearing threshold measurements in hypobaric environments are performed.Lucertini M, Botti T, Sanjust F, Cerini L, Autore A, Lucertini L, Sisto R. High altitude performance of loudspeakers and potential impact on audiometric findings. Aerosp Med Hum Perform. 2019; 90(7):655-659.

Auditory Verbal Working Memory Load Effects on a Simulator-Induced Spatial Disorientation Event.

INTRODUCTION: Working memory is an essential executive function for flying an aircraft and its limitations may jeopardize flight safety. This function is particularly critical when pilots have to struggle with spatial disorientation (SD) cues. This research aimed to assess the combined effect of the auditory N-back task (NBT) and simulator-induced SD cues on pilots' flight performance.METHODS: Using an SD simulator, 39 male military pilots (control N = 20; age M = 31.6; SD = 8.22, experimental N = 19; age M = 26.9; SD = 8.67) were exposed to 12 flight sequences, where 6 contained an SD conflict-3 with vestibular illusions and 3 with visual illusions. Additionally, the pilots from the experimental group were asked to perform an auditory NBT involving sound stimuli (the sequential letter memory task) as they performed during oriented and disoriented flight conditions.RESULTS: Pilots' flight performance from the NBT group were significantly worse than the control group in the approach and landing profiles involving visual illusions (for both nonconflict and conflict flight), and in the profile involving the false horizon illusion (only for the conflict flight). No increase in a pilot's susceptibility to SD was observed with any other profiles.DISCUSSION: The current study provides support that pilots' cognitive workload can negatively impact flight performance. Pilots are not always aware of altered flight parameters, which may indicate that they have lost spatial orientation, mainly as a result of visual illusion. If problems occur in maintaining proper flight parameters, pilots should direct all available mental resources to regain their orientation and withdraw from any other parallel tasks.Lewkowicz R, Strózak P, Balaj B, Francuz P. Auditory verbal working memory load effects on a simulator-induced spatial disorientation event. Aerosp Med Hum Perform. 2019; 90(6):531-539.

Urea and Minerals Monitoring in Space Missions by Spot Samples of Saliva and Urine.

BACKGROUND: Microgravity induces redistribution of body fluids and reductions in muscle and bone mass. These effects correlate with changes in lab test results, including urea and bone minerals. Difficulties with collecting blood and urine during space missions limit the available data. This pilot study investigated metabolic changes during a space mission using untimed spot samples of urine and saliva. Untimed spot urine was used for urinalysis with data normalization per creatinine concentration. Saliva was proven useful as an index of serum urea and phosphorus.METHODS: Two astronauts collected urine and saliva samples 75 ± 5 d before launch (baseline) and 3-5 times during a 6-mo space mission. Samples were collected 3 h after morning breakfast. Urine was collected using a standard NASA device. Saliva was collected using a Salivette™ synthetic swab. Samples were kept frozen using automated biochemistry until lab work-up. Anthropometric data were collected at baseline and after the mission.RESULTS: For astronauts 1 and 2, respectively, total bone mineral density decreased (-1.4% and -0.9%). In-flight changes were as follows: transiently decreased urine urea/creatinine ratio (-32% and -24%), transiently decreased urine phosphorus/creatinine ratio (-52% and -30%), increased urine calcium/creatinine ratio (up to +116% and +27%), and transient increases in saliva urea (up to +48% and +195%) and phosphorus (up to +29% and +46%). The astronaut with greater changes in urine minerals had greater reduction in bone mineral density.DISCUSSION: The results support the hypothesis that untimed samples of urine and saliva are useful for investigation of metabolic changes during space missions. Changes in urine and saliva minerals suggested down-regulation of parathyroid gland activity during the space mission.Bilancio G, Cavallo P, Lombardi C, Guarino E, Cozza V, Giordano F, Cirillo M. Urea and minerals monitoring in space missions by spot samples of saliva and urine. Aerosp Med Hum Perform. 2019; 90(1):43-47.

Simulation Training for In-Flight Medical Emergencies Improves Provider Knowledge and Confidence.

INTRODUCTION: In-flight medical emergencies require healthcare providers to operate in confined spaces with limited resources and delayed access to definitive care. These emergencies are common, with an estimated frequency of 1 per 100 to 1000 flights. Despite this, training for medical response in these environments is limited. We hypothesize that integrating such education into a pre-existing medical student elective course would improve knowledge and ability to respond appropriately to in-flight medical emergencies.METHODS: The available literature surrounding in-flight medical emergencies was reviewed. Syncope, respiratory distress, allergic reaction, and cardiac arrest were identified as common and potentially life-threatening complaints. Simulation cases were designed for each of these complaints and a simulation room was modified to mimic an airplane cabin. These simulation cases and accompanying relevant didactic lectures were incorporated into an existing wilderness and extreme environmental medicine course, with multiple-choice tests completed by the students at the beginning and end of the 2-wk course.RESULTS: Participating in this study were 18 students. The pretest average was 76%, which improved to 87% on the posttest. Qualitative feedback regarding this type of training was overwhelmingly positive.DISCUSSION: Simulation-based training for in-flight medical emergencies can significantly improve medical students' knowledge. This training was very well received by the students. Opportunities for training to manage in-flight medical emergencies remain limited; incorporating such training into existing curricula could provide a means by which to improve provider knowledge. Such a curriculum could be adapted for use by flight crews and other populations.Padaki A, Redha W, Clark T, Nichols T, Jacoby L, Slivka R, Ranniger C, Lehnhardt K. Simulation training for in-flight medical emergencies improves provider knowledge and confidence. Aerosp Med Hum Perform. 2018; 89(12):1076-1079.

Does effective gaze behavior lead to enhanced performance in a complex error-detection cockpit task?

The purpose of the current study was to examine the relationship between expertise, performance, and gaze behavior in a complex error-detection cockpit task. Twenty-four pilots and 26 non-pilots viewed video-clips from a pilot's viewpoint and were asked to detect malfunctions in the cockpit instrument panel. Compared to non-pilots, pilots detected more malfunctioning instruments, had shorter dwell times on the instruments, made more transitions, visited task-relevant areas more often, and dwelled longer on the areas between the instruments. These results provide evidence for three theories that explain underlying processes for expert performance: The long-term working memory theory, the information-reduction hypothesis, and the holistic model of image perception. In addition, the results for generic attentional skills indicated a higher capability to switch between global and local information processing in pilots compared to non-pilots. Taken together, the results suggest that gaze behavior as well as other generic skills may provide important information concerning underlying processes that can explain successful performance during flight in expert pilots.

On-orbit sleep problems of astronauts and countermeasures.

Sufficient sleep duration and good sleep quality are crucial to ensure normal physical and mental health, cognition and work performance for the common people, as well as astronauts. On-orbit sleep problem is very common among astronauts and has potential detrimental influences on the health of crewmembers and the safety of flight missions. Sleep in space is becoming a new medical research frontier. In this review we summarized on-orbit sleep problems of astronauts and six kinds of causes, and we presented the effects of lack of sleep on performance as well as mental and physical health, then we proposed seven kinds of countermeasures for sleep disturbance in spaceflight, including pharmacologic interventions, light treatment, crew selection and training, Traditional Chinese Medicine and so on. Furthermore, we discussed and oriented the prospect of researches on sleep in space.

Treating Decompression Sickness: Military Flight Simulation Site-Community Hospital Partnership.

BACKGROUND: High-altitude flight simulation familiarizes military trainees with the symptoms of hypoxia to prepare them for emergency situations. Decompression sickness (DCS) can occur as a result of these simulations. In cases when ground-level supplemental oxygen does not resolve symptoms, hyperbaric oxygen (HBO) therapy is indicated. Many military hyperbaric chambers have been closed because of cost reductions, necessitating partnerships with community hospitals to ensure access to treatment. MATERIALS AND METHODS: This article describes the unique arrangement between a community hospital in Colorado and a military training site to treat DCS cases emergently. We gathered cost data from the community hospital to estimate and compare the cost of providing HBO therapy in the hospital versus a standalone chamber similar to the former military hyperbaric chamber. RESULTS: Since the closure of the military hyperbaric chamber, the community hospital treated an estimated 50 patients with DCS requiring HBO therapy attributed to high-altitude flight simulation between October 2003 and April 2015. Cost to the institution providing HBO treatment varies widely on the basis of patient volume. Assuming a volume of five treatments, per-treatment cost at a standalone center is $95,380. In contrast, per-treatment cost at the hospital assuming a volume of 1,000 treatments commensurate with the hospital's ability to bill for other services is $698 per treatment. CONCLUSION: The cost analysis demonstrates that the per-treatment cost of operating a standalone HBO therapy center may be greater than 100 times that of operating a center at a community hospital, suggesting the arrangement is beneficial to the military.

Jugular and Portal Vein Volume, Middle Cerebral Vein Velocity, and Intracranial Pressure in Dry Immersion.

BACKGROUND: The objective was to determine if short term exposure to dry immersion (DI) results in a cephalic fluid shift similar to what has been observed with spaceflight. METHODS: Data were collected from 10 individuals at rest and during the first 2 h of dry immersion. Jugular vein (JV), portal vein (PV), and thyroid volume were measured using 3D echography. Middle cerebral vein velocity (MCVv) was determined using transcranial Doppler ultrasound. The cochlear response to audio stimulation was used to derive an estimate of intracranial pressure (dICP). RESULTS: After 2 h of DI, there was a significant increase (mean ± SD) in JV (2.21 ± 1.10 mL), PV (1.05 ± 0.48 mL), and thyroid (0.428 ± 0.313 mL) volume. MCVv was also significantly increased with DI (3.90 ± 5.03 cm · s-1). There was no change in dICP with DI in part due to large individual variability. The range of dICP changes appeared to be related to MCVv, with participants with the largest increase in MCVv also showing increased dICP. DISCUSSION: The results suggest that DI induces a significant cephalic fluid shift similar to what is observed with spaceflight. The increased thyroid volume suggests that cerebral tissue may also be subjected to similar fluid filtration, with implications for changes in intracranial pressure. However, despite all participants having an increase in JV and thyroid volume, only half showed an increase in dICP, suggesting that increased venous pooling alone is not sufficient to cause increased intracranial pressure.Arbeille P, Avan P, Treffel L, Zuj K, Normand H, Denise P. Jugular and portal vein volume, middle cerebral vein velocity, and intracranial pressure in dry immersion. Aerosp Med Hum Perform. 2017; 88(5):457-462.

US Air Force Behavioral Health Optimization Program: team members' satisfaction and barriers to care.

BACKGROUND: Research has shown significant contribution of integrated behavioural health care; however, less is known about the perceptions of primary care providers towards behavioural health professionals. OBJECTIVE: The current study examined barriers to care and satisfaction with integrated behavioural health care from the perspective of primary care team members. DESIGN: This study utilized archival data from 42 treatment facilities as part of ongoing program evaluation of the Air Force Medical Service's Behavioral Health Optimization Program. SETTING: This study was conducted in a large managed health care organization for active duty military and their families, with specific clinic settings that varied considerably in regards to geographic location, population diversity and size of patient empanelment. STUDY PARTICIPANTS: De-identified archival data on 534 primary care team members were examined. RESULTS: Team members at larger facilities rated access and acuity concerns as greater barriers than those from smaller facilities (t(533) = 2.57, P < 0.05). Primary Care Managers (PCMs) not only identified more barriers to integrated care (ß = -0.07, P < 0.01) but also found services more helpful to the primary care team (t(362.52) = 1.97, P = 0.05). Barriers to care negatively impacted perceived helpfulness of integrated care services for patients (ß = -0.12, P < 0.01) and team members, particularly among non-PCMs (ß = -0.11, P < 0.01). CONCLUSIONS: Findings highlight the potential benefits of targeted training that differs in facilities of larger empanelment and is mindful of team members' individual roles in a Patient Centered Medical Home. In particular, although generally few barriers were perceived, given the impact these barriers have on perception of care, efforts should be made to decrease perceived barriers to integrated behavioural health care among non-PCM team members.

Identifying the Subtle Presentation of Decompression Sickness.

BACKGROUND: Decompression sickness is an inherent occupational hazard that has the possibility to leave its victims with significant long-lasting effects that can potentially impact an aircrew's flight status. The relative infrequency of this hazard within the military flying community along with the potentially subtle presentation of decompression sickness (DCS) has the potential to result in delayed diagnosis and treatment, leading to residual deficits that can impact a patient's daily life or even lead to death. CASE REPORT: The patient presented in this work was diagnosed with a Type II DCS 21 h after a cabin decompression at 35,000 ft (10,668 m). The patient had been asymptomatic with a completely normal physical/neurological exam following his flight. The following day, he presented with excessive fatigue and on re-evaluation was recommended for hyperbaric therapy, during which his symptoms completely resolved. He was re-evaluated 14 d later and cleared to resume flight duties without further incident. DISCUSSION: The manifestation of this patient's decompression sickness was subtle and followed an evaluation that failed to identify any focal findings. A high index of suspicion with strict follow-up contributed to the identification of DCS in this case, resulting in definitive treatment and resolution of the patient's symptoms. Determination of the need for hyperbaric therapy following oxygen supplementation and a thorough history and physical is imperative. If the diagnosis is in question, consider preemptive hyperbaric therapy as the benefits of treatment in DCS outweigh the risks of treatment. Finally, this work introduces the future potential of neuropsychological testing for both the diagnosis of DCS as well as assessing the effectiveness of hyperbaric therapy in Type II DCS.

Conservative Management of Mechanical Neck Pain in a Helicopter Pilot.

BACKGROUND: Acute and chronic spinal symptoms such as neck pain may limit flying performance significantly and disqualify the pilot from flight duty. Mechanical neck pain is very common among pilots because of their exposure to vibration, +GZ forces, helmet weight, poor neck posture during air combat maneuvers, previous neck injuries, and poor treatment plans for such injuries. Successful treatment of such injuries requires appropriate therapeutic procedures as well as an aeromedical assessment. The aim of this case study was to demonstrate the benefits of conservative procedures such as spinal manipulation and mobilization therapy (SMMT) and exercise therapy (ET) in treating chronic mechanical neck pain in an Iranian commercial helicopter pilot. CASE REPORT: A 36-yr-old male patient presented to the clinic with moderate, intermittent nonradicular chronic neck pain and limited range of motion over a 2-yr period. The patient was treated with cervical and upper thoracic SMMT followed by home ET for 5 wk. After this period, the patient reported significant recovery and improvement in range of motion in his neck. DISCUSSION: Mechanical neck pain is very common among helicopter pilots. Although Air Force and Navy waiver guides recommend nonsteroidal anti-inflammatory medications as well as SMMT and ET, there are currently very few published studies that examine the benefits of manual and exercise therapy for treating mechanical neck pain in commercial and military pilots. Based on the results of this study, it seems that SMMT and ET may be a safe and effective in treatment of uncomplicated mechanical neck pain in helicopter pilots. Alagha B. Conservative management of mechanical neck pain in a helicopter pilot.

An Unusual Complication of Barotrauma at Altitude.

BACKGROUND: A case of unilateral optic neuropathy secondary to barotrauma following a medial orbital wall fracture is presented. CASE REPORT: A 41-yr-old U.S. Air Force aviator presented for a routine periodic health assessment. Evaluation uncovered a suspected acquired color deficiency in the right eye (OD). Subsequent discussions with the patient revealed a history of eye pain, redness, and proptosis during a flight overseas several years earlier. Local ocular examination demonstrated asymmetric optic nerve cupping, optic nerve pallor OD, a mild asymmetric color deficit, and a significant visual field defect OD. Evaluation with magnetic resonance imaging revealed findings consistent with an old medial orbital wall fracture OD and optic nerve findings consistent with optic neuropathy. Follow-up evaluation by neurology and otorhinolaryngology demonstrated only extensive sinus pathology. Based upon these findings, it is postulated that the member suffered a medial orbital wall fracture at altitude during ascent caused by expanding ethmoid sinus gases due to abnormal sinus anatomy with subsequent right optic nerve injury leading to an optic neuropathy and subsequent visual sequelae. DISCUSSION: This case demonstrates one possible complication of active sinus disease while working in the aerospace environment. Several case reports have been published demonstrating the potential link between eye injuries and working in an environment with fluctuating atmospheric pressure. However, literature addressing the specific in-flight environment causing such complications is lacking. Furthermore, the case supports the need for versatility and a broad knowledge base in practicing flight surgeons to evaluate ocular pathology.