Carbon Fiber-Based Twisted and Coiled Artificial Muscles (TCAMs) for Powered Ankle-Foot Orthoses.

Ankle foot orthoses (AFOs) control the position and motion of the ankle, compensate for weakness, and correct deformities. AFOs can be classified as passive or powered. Powered AFOs overcome the limitations of passive AFOs by adapting their performance to meet a variety of requirements. However, the actuators currently used to power AFOs are typically heavy, bulky, expensive, or limited to laboratory settings. Thus, there is a strong need for lightweight, inexpensive, and flexible actuators for powering AFOs. In this technical brief, carbon fiber/silicone rubber (CF/SR) twisted and coiled artificial muscles (TCAMs) are proposed as novel actuators for powered AFOs. CF/SR TCAMs can lift to 12,600 times their weight with an input power of only 0.025 W cm-1 and are fabricated from inexpensive materials through a low-cost manufacturing process. Additionally, they can provide a specific work of 758 J kg-1 when an input voltage of 1.64 V cm-1 is applied. Mechanical characterization of CF/SR TCAMs in terms of length/tension, tension/velocity, and active-passive length/tension is presented, and results are compared with the performance of skeletal muscles. A gait analysis demonstrates that CF/SR TCAMs can provide the performance required to supplement lower limb musculature and replicate the gait cycle of a healthy subject. Therefore, the preliminary results provided in this brief are a stepping stone for a dynamic AFO powered by CF/SR TCAMs.

Does tibialis posterior dysfunction correlate with a worse radiographic overall alignment in progressive collapsing foot deformity? A retrospective study.

BACKGROUND: Posterior Tibial Tendon (PTT) dysfunction is considered to have an important role in Progressive Collapsing Foot Deformity (PCFD). The objective of our study was to assess the relationship between PTT status and three-dimensional foot deformity in PCFD. METHODS: Records from 25 patients with PCFD were included for analysis. The PTT was considered deficient in patients with a positive single heel rise test or a deficit in inversion strength. Three-dimensional foot deformity was assessed using the Foot and Ankle Offset (FAO) from Weight-Bearing-CT imaging. Hindfoot valgus, midfoot abduction and medial longitudinal arch collapse were assessed on X-Rays using hindfoot moment arm, talonavicular coverage angle and Meary's angle respectively. Deland and Rosenberg MRI classifications were used to classify PTT degeneration. RESULTS: PCFD with PTT deficit (13/25) had a mean FAO of 7.75 + /- 3.8% whereas PCFD without PTT deficit had a mean FAO of 6.68 + /- 3.9% (p = 0.49). No significant difference was found between these groups on the hindfoot moment arm and the talonavicular coverage angle (respectively p = 0.54 and 0.32), whereas the Meary's angle was significantly higher in case of PCFD with PTT deficit (p = 0.037). No significant association was found between PTT degeneration on MRI and FAO. CONCLUSION: PCFD associated three-dimensional deformity, hindfoot valgus and midfoot abduction were not associated with PTT dysfunction. PTT dysfunction was only associated with a worse medial longitudinal arch collapse in our study. Considering our results, it does not appear that PTT is the main contributor to PCFD. LEVEL OF EVIDENCE: Level III, Retrospective Comparative Study.

Satisfaction with ankle foot orthoses in individuals with Charcot-Marie-Tooth disease.

BACKGROUND: Ankle foot orthoses (AFOs) are commonly prescribed to individuals with Charcot-Marie-Tooth disease (CMT). The aim of this study was to evaluate patient reported satisfaction with orthotic devices and services in individuals with CMT to provide preliminary data for advancing AFO development and improving clinical care. METHODS: The Orthotics and Prosthetics Users Survey was distributed via e-mail through the Inherited Neuropathy Consortium (INC) Contact Registry and includes 11 device-specific questions and 10 service-related questions. Participants were also asked open-ended questions about their experiences with AFOs. RESULTS: Three hundred and fourteen individuals completed the survey. Over one-third of participants provided negative responses, including dislike of AFO appearance, discomfort, abrasions or irritations, and pain. Ratings of orthotic services were generally positive. CONCLUSIONS: Lower scores related to discomfort, abrasions and pain identified areas for AFO improvement. Continued research in these areas will be beneficial to informing and advancing AFO development and improving clinical care.

Coccidioidomycosis outbreak among inmate wildland firefighters: California, 2017.

BACKGROUND: In California, state prison inmates are employed to fight wildfires, which involves performing soil-disrupting work. Wildfires have become more common, including areas where Coccidioides, the soil-dwelling fungus that causes coccidioidomycosis, proliferates. However, work practices that place wildland firefighters at risk for coccidioidomycosis have not been investigated. METHODS: On August 17, 2017, the California Department of Public Health was notified of a cluster of coccidioidomycosis cases among Wildfire A inmate wildland firefighters. We collected data through medical record abstraction from suspected case-patients and mailed a survey assessing potential job task risk factors to Wildfire A inmate firefighters. We described respondent characteristics and conducted a retrospective case-control investigation to assess coccidioidomycosis risk factors. RESULTS: Among 198 inmate firefighters who worked on Wildfire A, 112 (57%) completed the survey. Of 10 case-patients (four clinical and six laboratory-confirmed), two were hospitalized. In the case-control analysis of 71 inmate firefighters, frequently cutting fire lines with a McLeod tool (odds ratio [OR]: 5.5; 95% confidence interval [CI]: 1.1-37.2) and being in a dust cloud or storm (OR: 4.3; 95% CI: 1.1-17.4) were associated with illness. Two of 112 inmate firefighters reported receiving coccidioidomycosis training; none reported wearing respiratory protection on this wildfire. CONCLUSIONS: Wildland firefighters who use hand tools and work in dusty conditions where Coccidioides proliferates are at risk for coccidioidomycosis. Agencies that employ them should provide training about coccidioidomycosis and risk reduction, limit dust exposure, and implement respiratory protection programs that specify where respirator use is feasible and appropriate.

Muscle Contributions to Balance Control During Amputee and Nonamputee Stair Ascent.

Dynamic balance is controlled by lower-limb muscles and is more difficult to maintain during stair ascent compared to level walking. As a result, individuals with lower-limb amputations often have difficulty ascending stairs and are more susceptible to falls. The purpose of this study was to identify the biomechanical mechanisms used by individuals with and without amputation to control dynamic balance during stair ascent. Three-dimensional muscle-actuated forward dynamics simulations of amputee and nonamputee stair ascent were developed and contributions of individual muscles, the passive prosthesis, and gravity to the time rate of change of angular momentum were determined. The prosthesis replicated the role of nonamputee plantarflexors in the sagittal plane by contributing to forward angular momentum. The prosthesis largely replicated the role of nonamputee plantarflexors in the transverse plane but resulted in a greater change of angular momentum. In the frontal plane, the prosthesis and nonamputee plantarflexors contributed oppositely during the first half of stance while during the second half of stance, the prosthesis contributed to a much smaller extent. This resulted in altered contributions from the intact leg plantarflexors, vastii and hamstrings, and the intact and residual leg hip abductors. Therefore, prosthetic devices with altered contributions to frontal-plane angular momentum could improve balance control during amputee stair ascent and minimize necessary muscle compensations. In addition, targeted training could improve the force production magnitude and timing of muscles that regulate angular momentum to improve balance control.

Occupational coccidioidomycosis surveillance and recent outbreaks in California.

Workers in Coccidioides-endemic areas performing soil-disturbing work or exposed to windy and dusty conditions are at increased risk for coccidioidomycosis. Four occupational coccidioidomycosis outbreaks from 2007 to 2014 in California are described, involving construction workers in a number of excavation projects and an outdoor filming event involving cast and crew. These outbreaks highlight the importance of identifying industries and occupations at high risk for coccidioidomycosis, conducting targeted occupational health surveillance to assess the burden of illness, developing and implementing prevention strategies, and setting research priorities.

The effects of ankle stiffness on mechanics and energetics of walking with added loads: a prosthetic emulator study.

BACKGROUND: The human ankle joint has an influential role in the regulation of the mechanics and energetics of gait. The human ankle can modulate its joint 'quasi-stiffness' (ratio of plantarflexion moment to dorsiflexion displacement) in response to various locomotor tasks (e.g., load carriage). However, the direct effect of ankle stiffness on metabolic energy cost during various tasks is not fully understood. The purpose of this study was to determine how net metabolic energy cost was affected by ankle stiffness while walking under different force demands (i.e., with and without additional load). METHODS: Individuals simulated an amputation by using an immobilizer boot with a robotic ankle-foot prosthesis emulator. The prosthetic emulator was controlled to follow five ankle stiffness conditions, based on literature values of human ankle quasi-stiffness. Individuals walked with these five ankle stiffness settings, with and without carrying additional load of approximately 30% of body mass (i.e., ten total trials). RESULTS: Within the range of stiffness we tested, the highest stiffness minimized metabolic cost for both load conditions, including a ~ 3% decrease in metabolic cost for an increase in stiffness of about 0.0480 Nm/deg/kg during normal (no load) walking. Furthermore, the highest stiffness produced the least amount of prosthetic ankle-foot positive work, with a difference of ~ 0.04 J/kg from the highest to lowest stiffness condition. Ipsilateral hip positive work did not significantly change across the no load condition but was minimized at the highest stiffness for the additional load conditions. For the additional load conditions, the hip work followed a similar trend as the metabolic cost, suggesting that reducing positive hip work can lower metabolic cost. CONCLUSION: While ankle stiffness affected the metabolic cost for both load conditions, we found no significant interaction effect between stiffness and load. This may suggest that the importance of the human ankle's ability to change stiffness during different load carrying tasks may not be driven to minimize metabolic cost. A prosthetic design that can modulate ankle stiffness when transitioning from one locomotor task to another could be valuable, but its importance likely involves factors beyond optimizing metabolic cost.

Coccidioidomycosis Outbreak Among Workers Constructing a Solar Power Farm - Monterey County, California, 2016-2017.

In January 2017, two local health departments notified the California Department of Public Health (CDPH) of three cases of coccidioidomycosis among workers constructing a solar power installation (solar farm) in southeastern Monterey County. Coccidioidomycosis, or Valley fever, is an infection caused by inhalation of the soil-dwelling fungus Coccidioides, which is endemic in the southwestern United States, including California. After a 1-3 week incubation period, coccidioidomycosis most often causes influenza-like symptoms or pneumonia, but rarely can lead to severe disseminated disease or death (1). Persons living, working, or traveling in areas where Coccidioides is endemic can inhale fungal spores; workers who are performing soil-disturbing activities are particularly at risk. CDPH previously investigated one outbreak among solar farm construction workers that started in 2011 and made recommendations for reducing risk for infection, including worker education, dust suppression, and use of personal protective equipment (2,3). For the current outbreak, the CDPH, in collaboration with Monterey County and San Luis Obispo County public health departments, conducted an investigation that identified nine laboratory-confirmed cases of coccidioidomycosis among 2,410 solar farm employees and calculated a worksite-specific incidence rate that was substantially higher than background county rates, suggesting that illness was work-related. The investigation assessed risk factors for potential occupational exposures to identify methods to prevent further workplace illness.

Muscle Function and Coordination of Amputee Stair Ascent.

Ascending stairs is challenging following transtibial amputation due to the loss of the ankle muscles, which are critical to human movement. Efforts to improve stair ascent following amputation are hindered by limited understanding of how prostheses and remaining muscles contribute to stair ascent. This study developed a three-dimensional muscle-actuated forward dynamics simulation of amputee stair ascent to identify contributions of individual muscles and passive prosthesis to the biomechanical subtasks of stair ascent. The prosthesis was found to provide vertical propulsion throughout stair ascent, similar to non-amputee plantarflexors. However, the timing differed considerably. The prosthesis also contributed to braking, similar to non-amputee soleus, but to a greater extent. In contrast, the prosthesis was unable to replicate the functions of non-amputee gastrocnemius which contributes to forward propulsion during the second half of stance and leg swing initiation. To compensate, hamstrings and vasti of the residual leg increased their contributions to forward propulsion during the first and second halves of stance, respectively. The prosthesis also contributed to medial control, consistent with the non-amputee soleus but not gastrocnemius. Therefore, prosthesis designs that provide additional vertical propulsion as well as forward propulsion, lateral control and leg swing initiation at appropriate points in the gait cycle could improve amputee stair ascent. However, because non-amputee soleus and gastrocnemius contribute oppositely to many subtasks, it may be necessary to couple the prosthesis, which functions most similarly to soleus, with targeted rehabilitation programs focused on muscle groups that can compensate for gastrocnemius.

Muscle Function and Coordination of Stair Ascent.

Stair ascent is an activity of daily living and necessary for maintaining independence in community environments. One challenge to improving an individual's ability to ascend stairs is a limited understanding of how lower-limb muscles work in synergy to perform stair ascent. Through dynamic coupling, muscles can perform multiple functions and require contributions from other muscles to perform a task successfully. The purpose of this study was to identify the functional roles of individual muscles during stair ascent and the mechanisms by which muscles work together to perform specific subtasks. A three-dimensional (3D) muscle-actuated simulation of stair ascent was generated to identify individual muscle contributions to the biomechanical subtasks of vertical propulsion, anteroposterior (AP) braking and propulsion, mediolateral control and leg swing. The vasti and plantarflexors were the primary contributors to vertical propulsion during the first and second halves of stance, respectively, while gluteus maximus and hamstrings were the primary contributors to forward propulsion during the first and second halves of stance, respectively. The anterior and posterior components of gluteus medius were the primary contributors to medial control, while vasti and hamstrings were the primary contributors to lateral control during the first and second halves of stance, respectively. To control leg swing, antagonistic muscles spanning the hip, knee, and ankle joints distributed power from the leg to the remaining body segments. These results compliment previous studies analyzing stair ascent and provide further rationale for developing targeted rehabilitation strategies to address patient-specific deficits in stair ascent.

Experimental comparisons of passive and powered ankle-foot orthoses in individuals with limb reconstruction.

BACKGROUND: Ankle-foot orthoses (AFO) are commonly prescribed to provide functional assistance for patients with lower limb injuries or weakness. Their passive mechanical elements can provide some energy return to improve walking ability, but cannot restore plantar flexor push-off. Powered AFOs provide an assistive torque about the ankle to address the limitations of passive devices, but current designs have yet to be implemented on a large scale clinically. PURPOSE: To compare passive AFOs to a new untethered, powered AFO design in a clinical population with lower limb reconstruction. METHODS: A crossover study design, conducted on three individuals with lower limb reconstruction, compared gait mechanics at a standardized speed (based on leg length) in 4 AFO conditions: 1. None (shoes only), 2. Blue Rocker (BR, Allard, USA), 3. Intrepid Dynamic Exoskeletal Orthosis (IDEO), and 4. PowerFoot Orthosis (PFO BionX Medical Technologies, Inc.). The PFO was a custom, battery-powered device whose damping and power were capable to being tuned to meet patient needs. Subjects performed biomechanical gait analysis and metabolic testing at slow, moderate and fast speeds. Dependent variables included total limb power (calculated using a unified deformable segment model), mechanical work, mechanical efficiency, ankle motion, net metabolic cost across three speeds, and performance measures were calculated. Effect sizes (d) were calculated and d > 0.80 denoted a large effect. RESULTS: Net positive work (d > 1.17) and efficiency (d > 1.43) were greatest in the PFO. There were large effects for between limb differences in positive work for all conditions except the PFO (d = 0.75). The PFO normalized efficiency between the affected and unaffected limbs (d = 0.50), whereas efficiency was less on the affected limb for all other conditions (d > 1.69). Metabolic rate was not consistently lowest in any one AFO condition across speeds. Despite some positive results of the PFO, patient preferred their daily use AFO (2 IDEO, 1 BR). All participants indicated that mass and size were concerns with using the PFO. CONCLUSIONS: A novel PFO resulted in more biomimetic mechanical work and efficiency than commercially-available and custom passive AFO models. Although the powered AFO provided some biomechanical benefits, further improvements are warranted to improve patient satisfaction.

Dust Exposure and Coccidioidomycosis Prevention Among Solar Power Farm Construction Workers in California.

OBJECTIVES: To investigate if work activities, dust exposure, and protection measures were associated with a 2011 to 2014 coccidioidomycosis outbreak among workers constructing 2 solar farms in California. METHODS: In 2013, we mailed self-administered questionnaires to employees who were onsite at the solar farms where the outbreak occurred to identify cases of clinical coccidioidomycosis and compare with asymptomatic workers by using multivariate logistic regression. RESULTS: When we compared 89 workers with clinical coccidioidomycosis to 325 asymptomatic workers, frequently being in a dust cloud or storm (odds ratio [OR] = 5.93; 95% confidence interval [CI] = 3.18, 11.06) significantly increased the odds of clinical coccidioidomycosis, whereas frequently wetting soil before soil-disturbing activity (OR = 0.42; 95% CI = 0.24, 0.75) was protective. When we controlled for being in a dust cloud or storm, frequent soil disturbance significantly increased the odds of clinical coccidioidomycosis only among those who reported wearing a respirator infrequently (OR = 2.31; 95% CI = 1.27, 4.21). CONCLUSIONS: Utilization of personal and employer-driven safety practices and increased coccidioidomycosis awareness among construction workers should be considered during the planning of any construction work in coccidioidomycosis-endemic regions to prevent occupational infections and outbreaks.

Physical, Mental, and Financial Impacts From Drought in Two California Counties, 2015.

OBJECTIVES: To evaluate health impacts of drought during the most severe drought in California's recorded history with a rapid assessment method. METHODS: We conducted Community Assessments for Public Health Emergency Response during October through November 2015 in Tulare County and Mariposa County to evaluate household water access, acute stressors, exacerbations of chronic diseases and behavioral health issues, and financial impacts. We evaluated pairwise associations by logistic regression with pooled data. RESULTS: By assessment area, households reported not having running water (3%-12%); impacts on finances (25%-39%), property (39%-54%), health (10%-20%), and peace of mind (33%-61%); worsening of a chronic disease (16%-46%); acute stress (8%-26%); and considering moving (14%-34%). Impacts on finances or property were each associated with impacts on health and peace of mind, and acute stress. CONCLUSIONS: Drought-impacted households might perceive physical and mental health effects and might experience financial or property impacts related to the drought. Public Health Implications. Local jurisdictions should consider implementing drought assistance programs, including behavioral health, and consider rapid assessments to inform public health action.

Inhalational Chlorine Injuries at Public Aquatic Venues - California, 2008-2015.

In June 2015, personnel from California's Contra Costa Health Services Environmental Health and Hazardous Materials (hazmat) divisions were alerted to a possible chemical release at a swimming pool in an outdoor municipal water park. Approximately 50 bathers were in the pool when symptoms began; 34 (68%) experienced vomiting, coughing, or eye irritation. Among these persons, 17 (50%) were treated at the scene by Contra Costa's Emergency Medical Services (EMS) and released, and 17 (50%) were transported to local emergency departments; five patients also were evaluated later at an emergency department or by a primary medical provider. Environmental staff members determined that a chemical controller malfunction had allowed sodium hypochlorite and muriatic acid (hydrochloric acid) solutions to be injected into the main pool recirculation line while the recirculation pump was off; when the main recirculation pump was restarted, toxic chlorine gas (generated by the reaction of concentrated sodium hypochlorite and muriatic acid) was released into the pool. A review of 2008-2015 California pesticide exposure records identified eight additional such instances of toxic chlorine gas releases at public aquatic venues caused by equipment failure or human error that sickened 156 persons. Chemical exposures at public aquatic venues can be prevented by proper handling, storage, and monitoring of pool chemicals; appropriate equipment operation and maintenance; training of pool operators and staff members on pool chemical safety; and reporting of chemical exposures.

Establishing a Timeline to Discontinue Routine Testing of Asymptomatic Pregnant Women for Zika Virus Infection - American Samoa, 2016-2017.

The first patients with laboratory-confirmed cases of Zika virus disease in American Samoa had symptom onset in January 2016 (1). In response, the American Samoa Department of Health (ASDoH) implemented mosquito control measures (1), strategies to protect pregnant women (1), syndromic surveillance based on electronic health record (EHR) reports (1), Zika virus testing of persons with one or more signs or symptoms of Zika virus disease (fever, rash, arthralgia, or conjunctivitis) (1-3), and routine testing of all asymptomatic pregnant women in accordance with CDC guidance (2,3). All collected blood and urine specimens were shipped to the Hawaii Department of Health Laboratory for Zika virus testing and to CDC for confirmatory testing. Early in the response, collection and testing of specimens from pregnant women was prioritized over the collection from symptomatic nonpregnant patients because of limited testing and shipping capacity. The weekly numbers of suspected Zika virus disease cases declined from an average of six per week in January-February 2016 to one per week in May 2016. By August, the EHR-based syndromic surveillance (1) indicated a return to pre-outbreak levels. The last Zika virus disease case detected by real-time, reverse transcription-polymerase chain reaction (rRT-PCR) occurred in a patient who had symptom onset on June 19, 2016. In August 2016, ASDoH requested CDC support in assessing whether local transmission had been reduced or interrupted and in proposing a timeline for discontinuation of routine testing of asymptomatic pregnant women. An end date (October 15, 2016) was determined for active mosquito-borne transmission of Zika virus and a timeline was developed for discontinuation of routine screening of asymptomatic pregnant women in American Samoa (conception after December 10, 2016, with permissive testing for asymptomatic women who conceive through April 15, 2017).

Blood Flow Restriction Training After Knee Arthroscopy: A Randomized Controlled Pilot Study.

INTRODUCTION: Quadriceps strength after arthroscopic knee procedures is frequently diminished several years postoperation. Blood flow restriction (BFR) training uses partial venous occlusion while performing submaximal exercise to induce muscle hypertrophy and strength improvements. The purpose of this study was to evaluate BFR as a postoperative therapeutic intervention after knee arthroscopy. METHODS: A randomized controlled pilot study comparing physical therapy with and without BFR after knee arthroscopy was conducted. Patients underwent 12 sessions of supervised physical therapy. Subjects followed the same postoperative protocol with the addition of 3 additional BFR exercises. Outcome measures included thigh girth, physical function measures, Knee Osteoarthritis Outcome Score (KOOS), Veterans RAND 12-Item Health Survey (VR12), and strength testing. Bilateral duplex ultrasonography was used to evaluate for deep venous thrombosis preintervention and postintervention. RESULTS: Seventeen patients completed the study. Significant increases in thigh girth were observed in the BFR group at 6-cm and 16-cm proximal to the patella (P = 0.0111 and 0.0001). All physical outcome measures significantly improved in the BFR group, and the timed stair ascent improvements were greater than conventional therapy (P = 0.0281). The VR-12 and KOOS subscales significantly improved in the BFR group, and greater improvement was seen in VR-12 mental component score (P = 0.0149). The BFR group displayed approximately 2-fold greater improvements in extension and flexion strength compared with conventional therapy (74.59% vs 33.5%, P = 0.034). No adverse events were observed during the study. CONCLUSIONS: This study suggests that BFR is an effective intervention after knee arthroscopy. Further investigation is warranted to elucidate the benefits of this intervention in populations with greater initial impairment.

Occupational HIV Transmission Among Male Adult Film Performers - Multiple States, 2014.

In 2014, the California Department of Public Health was notified by a local health department of a diagnosis of acute human immunodeficiency virus (HIV) infection* and rectal gonorrhea in a male adult film industry performer, aged 25 years (patient A). Patient A had a 6-day history of rash, fever, and sore throat suggestive of acute retroviral syndrome at the time of examination. He was informed of his positive HIV and gonorrhea test results 6 days after his examination. Patient A had a negative HIV-1 RNA qualitative nucleic acid amplification test (NAAT)(†) 10 days before symptom onset. This investigation found that during the 22 days between the negative NAAT and being informed of his positive HIV test results, two different production companies directed patient A to have condomless sex with a total of 12 male performers. Patient A also provided contact information for five male non-work-related sexual partners during the month before and after his symptom onset. Patient A had additional partners during this time period for which no locating information was provided. Neither patient A nor any of his interviewed sexual partners reported taking HIV preexposure prophylaxis (PrEP). Contact tracing and phylogenetic analysis of HIV sequences amplified from pretreatment plasma revealed that a non-work-related partner likely infected patient A, and that patient A likely subsequently infected both a coworker during the second film production and a non-work-related partner during the interval between his negative test and receipt of his positive HIV results. Adult film performers and production companies, medical providers, and all persons at risk for HIV should be aware that testing alone is not sufficient to prevent HIV transmission. Condom use provides additional protection from HIV and sexually transmitted infections (STIs). Performers and all persons at risk for HIV infection in their professional and personal lives should discuss the use of PrEP with their medical providers.

Thyroid Hormones and Timing of Pubertal Onset in a Longitudinal Cohort of Females, Northern California, 2006-11.

BACKGROUND: Pubertal timing is regulated by a complex interplay of hormones. Few studies have evaluated the role of thyroid hormones in pubertal onset. We investigated the associations between blood concentrations of free and total thyroxine (FT4, TT4), free triiodothyronine, and thyroid stimulating hormone and pubertal onset among females. METHODS: Participants included 323 Kaiser Permanente Northern California members followed at annual intervals during 2004-11, who provided a blood sample during the first 3 years of the study. Thyroid hormone concentrations were measured in serum in the first blood specimen available for each participant. Pubertal onset was defined as Tanner stage ≥2 for breast (thelarche) and pubic hair (pubarche) development. Associations between thyroid hormones and pubertal onset were assessed by multivariable logistic regression and Cox proportional hazards modelling. RESULTS: At blood draw, participants were age 6.5-10.1 (median 7.7) years, 10% had reached thelarche, and 12% had reached pubarche. Participants were followed 0-5 years after blood draw (median 4). At most recent clinical visit, participants were age 6.7-14.7 (median 12.3) years, 92% had reached thelarche, and 89% had reached pubarche. No associations were identified between having reached thelarche or pubarche at time of blood draw and thyroid hormones. Examined longitudinally, higher concentrations of pre-pubertal FT4 and TT4 were associated with earlier pubarche (adjusted hazard ratio (HR) 1.41, 95% confidence interval (CI) 1.06, 1.86; per ng/dL and aHR 1.07, 95% CI 1.02, 1.12; per µg/dL respectively). CONCLUSIONS: Higher pre-pubertal concentrations of FT4 and TT4 are associated with earlier pubarche.

Range of Motion Requirements for Upper-Limb Activities of Daily Living.

OBJECTIVE: We quantified the range of motion (ROM) required for eight upper-extremity activities of daily living (ADLs) in healthy participants. METHOD: Fifteen right-handed participants completed several bimanual and unilateral basic ADLs while joint kinematics were monitored using a motion capture system. Peak motions of the pelvis, trunk, shoulder, elbow, and wrist were quantified for each task. RESULTS: To complete all activities tested, participants needed a minimum ROM of -65°/0°/105° for humeral plane angle (horizontal abduction-adduction), 0°-108° for humeral elevation, -55°/0°/79° for humeral rotation, 0°-121° for elbow flexion, -53°/0°/13° for forearm rotation, -40°/0°/38° for wrist flexion-extension, and -28°/0°/38° for wrist ulnar-radial deviation. Peak trunk ROM was 23° lean, 32° axial rotation, and 59° flexion-extension. CONCLUSION: Full upper-limb kinematics were calculated for several ADLs. This methodology can be used in future studies as a basis for developing normative databases of upper-extremity motions and evaluating pathology in populations.

Coccidioidomycosis among Workers Constructing Solar Power Farms, California, USA, 2011-2014.

Coccidioidomycosis is associated with soil-disruptive work in Coccidioides-endemic areas of the southwestern United States. Among 3,572 workers constructing 2 solar power-generating facilities in San Luis Obispo County, California, USA, we identified 44 patients with symptom onset during October 2011-April 2014 (attack rate 1.2 cases/100 workers). Of these 44 patients, 20 resided in California outside San Luis Obispo County and 10 resided in another state; 9 were hospitalized (median 3 days), 34 missed work (median 22 days), and 2 had disseminated disease. Of the 25 patients who frequently performed soil-disruptive work, 6 reported frequent use of respiratory protection. As solar farm construction in Coccidioides-endemic areas increases, additional workers will probably be exposed and infected unless awareness is emphasized and effective exposure reduction measures implemented, including limiting dust generation and providing respiratory protection. Medical providers, including those in non-Coccidioides-endemic areas, should suspect coccidioidomycosis in workers with compatible illness and report cases to their local health department.