A Comparative Investigation of Equine-Related and Bovine-Related Human Fatalities in Oklahoma.

ABSTRACT: This study examined 71 cases, where 45 cases were equine-related and 26 were bovine-related. Data for this study were collected by examining cases between 2000 and 2022 from the Oklahoma Office of the Chief Medical Examiner database.A majority of the equine-related fatality cases involved males aged 0 to 18 and 60 to 69 years, with sustained injuries of the head, neck, and thoracic regions while being mounted. These injuries were most often inflicted by being kicked or resulted from blunt force of impact. A majority of the bovine-related fatality cases involved males aged 60 to 79 years, with sustained injuries of the head, neck, and thoracic regions while being unmounted. These injuries were most often inflicted by being butted, trampled, or resulted from blunt force of impact. Of the total cases, approximately 42% of the causes of death were blunt force trauma of the head/neck and nearly 34% were multiple blunt force injuries. Only 3 mechanisms of death were discussed.There are distinct similarities in the most prominent gender, cause of sustained injury, and location of injury between equine- and bovine-related fatalities in Oklahoma. This study lends significant support to the need for increased awareness of safe handling practices and safety precaution education for both equine and bovine activities.

Posterior reversible encephalopathy syndrome in the emergency department: A single center retrospective study.

INTRODUCTION: Posterior Reversible Encephalopathy Syndrome (PRES) and the related term Reversible Posterior Leukoencephalopathy Syndrome (RPLS) denote a constellation of clinical symptoms paired with key radiological findings. These symptoms may include headache, altered mental status, visual changes, and seizures. PRES is a rare condition and remains a challenging diagnosis to make in the emergency department. Data on risk factors and clinical presentation are limited, and there is no recent literature-supported diagnostic criteria. Our primary objective was to identify initial symptoms, clinical presentation, and risk factors that should guide the emergency clinician to consider a diagnosis of PRES. A secondary objective was to identify associations between risk factors and the outcomes of mortality and ICU admissions. METHODS: This was a retrospective, observational study that evaluated patients seen in the Emergency Department (ED) in an urban tertiary care center with the diagnosis of PRES or RPLS from 1/1/2008 to 1/1/2018. The Health System's Electronic Medical Record was used to collect data. Search criteria included any patient diagnosed with Posterior Reversible Encephalopathy Syndrome (PRES) or Reversible Posterior Leukoencephalopathy Syndrome (RPLS), and excluded patients under 18 years of age, transfer patients, or patients that were not evaluated in our emergency department. RESULTS: We identified 98 patients based on our initial search criteria. After a chart review, 27 patients met our predefined eligibility criteria. In patients with confirmed diagnosis of PRES, the majority were female (70%) and 37% were either on an immunomodulator or undergoing chemotherapy at the time of presentation. 67% of patients presented with altered mental status, 41% had a focal neurologic deficit, and 37% had a witnessed seizure prior to diagnosis. Headache (48%), nausea (33%), and vision changes (30%) were the next most common reported symptoms. The majority of patients were hypertensive at time of presentation (82%) and many had a past medical history of hypertension (78%); twelve were given anti-hypertensive medications. 33% of the patients were admitted to the ICU and 26% died. There were no statistical associations found between documented ED interventions and the outcome of mortality. CONCLUSION: PRES is difficult to identify and diagnose in the emergency department. Significant risk factors such as female gender, hypertension, and those currently undergoing active immunotherapy/chemotherapy are associated with PRES. Common presenting complaints and exam findings include headache, altered mental status, and neurologic deficits. Emergency providers should consider PRES in patients presenting with altered mental status with significant risk factors, especially with neurologic deficits for which stroke has been ruled out.

Overall Greater Demands on the Musculoskeletal System at Multiple Walking Speeds in Service Members With Lower Limb Loss.

Individuals with lower limb loss often walk with altered/asymmetric movement mechanics, postulated as a catalyst for development of low back and knee pain. Here, the authors simultaneously investigated trunk-pelvic movement patterns and lower limb joint kinematics and kinetics among 38 males with traumatic, unilateral lower limb loss (23 transtibial and 15 transfemoral), and 15 males without limb loss, at a self-selected and 2 standardized (1.0 and 1.6 m/s) speeds. Individuals with versus without lower limb loss walked with greater trunk range of motion in the frontal and transverse planes at all speeds (despite ∼10% slower self-selected speeds). At all speeds, individuals with versus without limb loss exhibited +29% larger medial ground reaction forces, and at 1.6 m/s also exhibited +50% to 110% larger vertical hip power generation, +27% to 80% larger vertical hip power absorption, and +21% to 90% larger medial-lateral hip power absorption. Moreover, pervasive biomechanical differences between transtibial versus transfemoral limb loss identify amputation-level movement strategies. Overall, greater demands on the musculoskeletal system across walking speeds, particularly at the hip, knee, and low back, highlight potential risk factors for the development/recurrence of prevalent secondary musculoskeletal conditions (eg, joint degeneration and pain) following limb loss.

Roller Massage Prior to Running Does Not Affect Gait Mechanics in Well-Trained Runners.

CONTEXT: Understanding if roller massage prior to a run can mitigate fatigue-related decrements in muscle force production during prolonged running is important because of the association between fatigue and running-related injury. OBJECTIVE: The authors investigated whether a bout of roller massage prior to running would (1) mitigate fatigue-related increases in vertical average load rate and free moment of the ground reaction force of running and (2) mitigate decreases in maximal countermovement jump height. DESIGN: Repeated-measures study. SETTING: Laboratory. PARTICIPANTS: A total of 14 recreational endurance athletes (11 men and 3 women) volunteered for the study. INTERVENTIONS: A 12.5-minute foam roller protocol for the lower extremities and a fatiguing 30-minute treadmill run. MAIN OUTCOME MEASURES: Vertical average load rate, free moment, and maximal jump height before (PRE) and after (POST) the fatiguing treadmill run on separate experimental days: once where participants sat quietly prior to the fatiguing run (REST) and another where the foam roller protocol was performed prior to the run (ROLL). RESULTS: A 2-way multiple analysis of variance found no significant differences in vertical average load rate, free moment, and jump height between PRE/POST times in both REST/ROLL conditions. CONCLUSIONS: The authors concluded that recreational endurance athletes maintain running mechanics and jump performance after a fatiguing run regardless of prerun roller massage and may not rely on prerun roller massage as a form of injury prevention.

Effects of Self-Selected Step Length and Trunk Position on Joint Kinetics in Highly Physically Fit Older Adults.

The causes of age-related differences in lower-extremity joint moments and powers are unknown. The purpose of this study was to determine the effects of highly physically active older adults walking with (1) a step length similar to young adults and (2) an upright trunk posture, on hip and ankle joint kinetics. The authors hypothesized that, compared with their self-selected walking mechanics, older adults would exhibit decreased hip kinetics and increased ankle kinetics when prescribed a young adult step length, and would exhibit decreased hip extension moments when maintaining an upright trunk posture during walking. A total of 12 active older adults (67 [5] y) and 13 active young adults (21 [3] y) walked at 1.3 m/s. The older adults also walked at 1.3 m/s with step lengths prescribed from height-matched young adults and, in a separate condition, walked with an upright trunk. The older adults did not display larger ankle kinetics or smaller hip kinetics in either condition compared to walking with a self-selected step length. These findings indicate that step length and trunk position do not primarily contribute to age-related differences in kinetics in highly active older adults and should serve as a starting point for investigating alternative explanations.

Standardized Lab Shoes Do Not Decrease Loading Rate Variability in Recreational Runners.

Studies of running mechanics often use a standardized lab shoe, ostensibly to reduce variance between subjects; however, this may induce unnatural running mechanics. The purpose of this study was to compare the step rate, vertical average loading rate, and ground contact time when running in standardized lab shoes versus participants' normal running shoes. Ground reaction forces were measured while the participants ran overground in both shoe conditions at a self-selected speed. The Student's t-test revealed that the vertical average loading rate magnitude was smaller in lab shoes versus normal shoes (42.09 [11.08] vs 47.35 [10.81] body weight/s, P = .013), while the step rate (170.92 [9.43] vs 168.98 [9.63] steps/min, P = .053) and ground contact time were similar (253 [25] vs 251 [20] ms, P = .5227) and the variance of all outcomes was similar in lab shoes versus normal shoes. Our results indicate that using standardized lab shoes during testing may underestimate the loads runners actually experience during their typical mileage.

Micropapillary adenocarcinoma of lung: Morphological criteria and diagnostic reproducibility among pulmonary pathologists.

CONTEXT: Invasive micropapillary adenocarcinoma (MPC) is an aggressive variant of lung adenocarcinoma, frequently manifesting with advanced stage lymph node metastasis and decreased survival. OBJECTIVE: Identification of this morphology is important, as it is strongly correlated with poor prognosis regardless of the amount of MPC component. To date, no study has investigated the morphological criteria used to objectively diagnose it. DESIGN: Herein, we selected 30 cases of potential MPC of lung, and distributed 2 digital images per case among 15 pulmonary pathology experts. Reviewers were requested to diagnostically interpret, assign the percentage of MPC component, and record the morphological features they identified. The noted features included: columnar cells, elongated slender cell nests, extensive stromal retraction, lumen formation with internal epithelial tufting, epithelial signet ring-like forms, intracytoplasmic vacuolization, multiple nests in the same alveolar space, back-to-back lacunar spaces, epithelial nest anastomosis, marked pleomorphism, peripherally oriented nuclei, randomly distributed nuclei, small/medium/large tumor nest size, fibrovascular cores, and spread through air-spaces (STAS). RESULTS: Cluster analysis revealed three subgroups with the following diagnoses: "MPC", "combined papillary and MPC", and "others". The subgroups correlated with the reported median percentage of MPC. Intracytoplasmic vacuolization, epithelial nest anastomosis/confluence, multiple nests in the same alveolar space, and small/medium tumor nest size were the most common criteria identified in the cases diagnosed as MPC. Peripherally oriented nuclei and epithelial signet ring-like forms were frequently identified in both the "MPC" and "combined papillary and MPC" groups. CONCLUSIONS: Our study provides objective diagnostic criteria to diagnose MPC of lung.

Flat epithelial atypia in directional vacuum-assisted biopsy of breast microcalcifications: surgical excision may not be necessary.

The aim of this study was to analyze the clinicopathological features of patients with flat epithelial atypia, diagnosed in directional vacuum-assisted biopsy targeting microcalcifications, to identify upgrade rate to in situ ductal or invasive breast carcinoma, and determine factors predicting carcinoma in the subsequent excision. We retrospectively evaluated the histological, clinical, and mammographic features of 69 cases from 65 women, with directional vacuum-assisted biopsy-diagnosed flat epithelial atypia with or without atypical ductal hyperplasia or atypical lobular hyperplasia, which underwent subsequent surgical excision. The extent and percentage of microcalcifications sampled by directional vacuum-assisted biopsy were evaluated by mammography. All biopsy and surgical excision slides were reviewed. The age of the women ranged from 40 to 85 years (mean 57 years). All patients presented with mammographically detected microcalcifications only, except in one case that had associated architectural distortion. Extent of calcifications ranged from <1 cm (n = 47), 1-3 cm (n = 15) to > 3 cm (n = 6), and no measurement (n = 1). A mean of 11 cores (range 6-25) was obtained from each lesion. Post-biopsy mammogram revealed >90% removal of calcifications in 81% of cases. Pure flat epithelial atypia represented nearly two-thirds of directional vacuum-assisted biopsy specimens (n = 43, 62%), while flat epithelial atypia coexisted with atypical ductal hyperplasia (18 cases, 26%), or atypical lobular hyperplasia (8 cases, 12%). Upon excision, none of the cases were upgraded to in situ ductal or invasive breast cancer. In one case, however, an incidental, tubular carcinoma (4 mm) was found away from biopsy site. Excluding this case, the upgrade rate was 0%. Our study adds to the growing evidence that diagnosis of flat epithelial atypia on directional vacuum-assisted biopsy for microcalcifications as the only imaging finding is not associated with a significant upgrade to carcinoma on excision, and therefore, excision may not be necessary. Additionally, excision may not be necessary for flat epithelial atypia with atypical ductal hyperplasia limited to ≤2 terminal duct-lobular units, if at least 90% of calcifications have been removed on biopsy.

Small cell and non small cell lung cancer form metastasis on cellular 4D lung model.

BACKGROUND: Metastasis is the main cause of death for lung cancer patients. The ex vivo 4D acellular lung model has been shown to mimic this metastatic process. However, the main concern is the model's lack of cellular components of the tumor's microenvironment. In this study, we aim to determine if the intact lung microenvironment will still allow lung cancer metastasis to form. METHODS: We harvested a heart-lung block from a rat and placed it in a bioreactor after cannulating the pulmonary artery, trachea and tying the right main bronchus for 10-15 days without any tumor cells as a control group or with NSCLC (A549, H1299 or H460), SCLC (H69, H446 or SHP77) or breast cancer cell lines (MCF7 or MDAMB231) through the trachea. We performed lobectomy, H&E staining and IHC for human mitochondria to determine the primary tumor's growth and formation of metastatic lesions. In addition, we isolated circulating tumor cells (CTC) from the model seeded with GFP tagged cells. RESULTS: In the control group, no gross tumor nodules were found, H&E staining showed hyperplastic cells and IHC showed no staining for human mitochondria. All of the models seeded with cancer cell lines formed gross primary tumor nodules that had microscopic characteristics of human cancer cells on H&E staining with IHC showing staining for human mitochondria. CTC were isolated for those cells labeled with GFP and they were viable in culture. Finally, all cell lines formed metastatic lesions with cells stained for human mitochondria. CONCLUSION: The cellular ex vivo 4D model shows that human cancer cells can form a primary tumor, CTC and metastatic lesions in an intact cellular environment. This study suggests that the natural matrix scaffold is the only necessary component to drive metastatic progression and that cellular components play a role in modulating tumor progression.

Landscape-level bird loss increases the prevalence of honeydew-producing insects and non-native ants.

Bird exclusion experiments consistently show that birds exhibit strong top-down control of arthropods, including ants and the honeydew-producing insects (HPIs) that they tend. However, it remains unclear whether the results of these small-scale bird exclosure experiments can be extrapolated to larger spatial scales. In this study, we use a natural bird removal experiment to compare the prevalence of ants and HPIs between Guam, an island whose bird community has been extirpated since the 1980s due to the introduction of the brown tree snake, and two nearby islands (Rota and Saipan) that have more intact bird assemblages. Consistent with smaller-scale bird exclosure experiments, we show that (1) forest trees from Guam are significantly more likely to host HPIs than trees from Saipan and (2) ants are nearly four times as abundant on Guam than on both Saipan and Rota. The prevalence of HPIs varied slightly based on tree species identity, although these effects were not as strong as island-level effects associated with bird loss. Ant community composition differed between Guam and the other two islands. These results corroborate past observational studies showing increased spider densities on Guam and suggest that trophic changes associated with landscape-level bird extirpation may also involve alterations in the abundance of ants and HPIs. This study also provides a clear example of the strong indirect effects that invasive species can have on natural food webs.

Joint Loading in Runners Does Not Initiate Knee Osteoarthritis.

Runners do not have a greater prevalence of knee osteoarthritis (OA) than nonrunners. The hypothesis that joint loads in running do not cause OA is forwarded. Two mechanisms are proposed: 1) cumulative load, which is surprisingly low in running, is more important for OA risk than peak load, and 2) running conditions cartilage to withstand the mechanical stresses of running.

Adverse tissue reactions after total hip arthroplasty.

Hip arthroplasty is commonly performed on patients with debilitating hip disease to relieve symptoms and improve quality of life. Generally, long-term success rates are excellent. However, a subset of patients requires revision due to prosthesis failure. A wide array of microscopic findings can be seen in surrounding tissues and many of the findings are etiologically nonspecific. The aim of this review is to discuss the etiologies and accompanying adverse tissue reactions seen with prosthesis failure, including the findings seen in aseptic lymphocyte-dominated vasculitis-associated lesion. Aseptic lymphocyte-dominated vasculitis-associated lesion is an important diagnostic consideration as its proposed pathogenesis is a type VI hypersensitivity response to metal ions. In addition, we also propose a diagnostic algorithm that incorporates clinical and histopathologic findings to suggest an etiologic cause. This proposed algorithm may be clinically useful as, to date, there is no consensus on nomenclature.

Health Supply Utilization at a Boy Scout Summer Camp: An Evaluation for Improvement and Preparedness.

OBJECTIVE: To describe the health conditions treated by a health services center at a Boy Scout summer camp and make recommendations for appropriate resources and supplies. METHODS: We conducted a retrospective review of health center utilization at a Boy Scout camp in central Missouri during the summers of 2012 and 2013. Health logbook data were compiled and analyzed using descriptive and comparative statistics. RESULTS: During the study period 19,771 camp participants made 1586 visits to the health care center. The overall incidence rate of health center visits was 6.20 visits per 1000 camp days. Two-thirds of visits were for illness and the remainder for injury. Over 90% of patients were returned to camp, 7.3% were transferred to another health facility, and 1.6% were advised to leave camp and return home. The most common treatments were rehydration (17.8 %) and administration of analgesics (13.4%) and topical creams (12.3%). CONCLUSIONS: Summer camps need to be prepared for a wide range of conditions and injuries in youth campers, leaders, and staff members. Over 90% of presenting complaints were managed on site, and the majority of conditions were easily treatable minor injuries and illnesses. We provide recommendations for appropriate medical supplies and suggest opportunities for improvement to aid health centers in planning and treatment.

The role of tactile sensation in online and offline hierarchical control of multi-finger force synergy.

The hand, one of the most versatile but mechanically redundant parts of the human body, must overcome imperfect motor commands and inherent noise in both the sensory and motor systems in order to produce desired motor actions. For example, it is nearly impossible to produce a perfectly consistent note during a single violin stroke or to produce the exact same note over multiple strokes, which we denote online and offline control, respectively. To overcome these challenges, the central nervous system synergistically integrates multiple sensory modalities and coordinates multiple motor effectors. Among these sensory modalities, tactile sensation plays an important role in manual motor tasks by providing hand-object contact information. The purpose of this study was to investigate the role of tactile feedback in individual finger actions and multi-finger interactions during constant force production tasks. We developed analytical techniques for the linear decomposition of the overall variance in the motor system in both online and offline control. We removed tactile feedback from the fingers and demonstrated that tactile sensors played a critical role in the online control of synergistic interactions between fingers. In contrast, the same sensors did not contribute to offline control. We also demonstrated that when tactile feedback was removed from the fingers, the combined motor output of individual fingers did not change while individual finger behaviors did. This finding supports the idea of hierarchical control where individual fingers at the lower level work together to stabilize the performance of combined motor output at the higher level.

A dynamical systems analysis of assisted and unassisted anterior and posterior hand-held load carriage.

Load carriage is recognised as a primary occupational factor leading to slip and fall injuries, and therefore assessing balance maintenance during such tasks is critical in assessing injury risk. Ten males completed 55 strides under five carriage conditions: (1) unassisted anterior, (2) unassisted posterior, (3) assisted anterior, (4) assisted posterior and (5) unloaded gait (UG). Kinematic data were recorded from markers affixed to landmarks on the right side of each participant, in order to calculate segment angles for the foot, shank, thigh and pelvis. Continuous relative phase (CRP) variability was calculated for each segment pair and local dynamic stability was calculated for each segment in all three movement planes. In general, irrespective of the assistive device or movement plane, anterior load carriage was most stable (lower CRP variability and maximum finite-time Lyapunov exponents). Moreover, load carriage was less dynamically stable than UG, displaying the importance of objectively investigating safe load carriage practices. PRACTITIONER SUMMARY: Dynamical systems analyses were used to comprehensively evaluate the stability of various handheld load carriage methods. In general, anterior load carriage was significantly more stable than posterior load carriage,Mover's assistive device had small but beneficial effects on stability, and load carriage was less stable than UG.

Transfemoral limb loss modestly increases the metabolic cost of optimal control simulations of walking.

Background: In transtibial limb loss, computer simulations suggest that the maintenance of muscle strength between pre- and post-limb loss can maintain the pre-limb loss metabolic cost. These results are consistent with comparable costs found experimentally in select cases of high functioning military service members with transtibial limb loss. It is unlikely that similar results would be found with transfemoral limb loss, although the theoretical limits are not known. Here we performed optimal control simulations of walking with and without an above-knee prosthesis to determine if transfemoral limb loss per se increases the metabolic cost of walking. Methods: OpenSim Moco was used to generate optimal control simulations of walking in 15 virtual "subjects" that minimized the weighted sum of (i) deviations from average able-bodied gait mechanics and (ii) the gross metabolic cost of walking, pre-limb loss in models with two intact biological limbs, and post-limb loss with one of the limbs replaced by a prosthetic knee and foot. No other changes were made to the model. Metabolic cost was compared between pre- and post-limb loss simulations in paired t-tests. Results: Metabolic cost post-limb loss increased by 0.7-9.3% (p < 0.01) depending on whether cost was scaled by total body mass or biological body mass and on whether the prosthetic knee was passive or non-passive. Conclusions: Given that the post-limb loss model had numerous features that predisposed it to low metabolic cost, these results suggest transfemoral limb loss per se increases the metabolic cost of walking. However, the large differences above able-bodied peers of ∼20-45% in most gait analysis experiments may be avoidable, even when minimizing deviations from able-bodied gait mechanics. Portions of this text were previously published as part of a preprint (https://www.biorxiv.org/content/10.1101/2023.06.26.546515v2.full.pdf).

Is there an association between elevated or low serum levels of phosphorus, parathyroid hormone, and calcium and mortality in patients with end stage renal disease? A meta-analysis.

BACKGROUND: Biochemical markers of altered mineral metabolism have been associated with increased mortality in end stage renal disease patients. Several studies have demonstrated non-linear (U-shaped or J-shaped) associations between these minerals and mortality, though many researchers have assumed linear relationships in their statistical modeling. This analysis synthesizes the non-linear relationships across studies. METHODS: We updated a prior systematic review through 2010. Studies included adults receiving dialysis and reported categorical data for calcium, phosphorus, and/or parathyroid hormone (PTH) together with all-cause mortality. We performed 2 separate meta-analyses to compare higher-than-referent levels vs referent and lower-than-referent levels vs referent levels. RESULTS: A literature review showed that when a linear relationship between the minerals and mortality was assumed, the estimated associations were more likely to be smaller or non-significant compared to non-linear models. In the meta-analyses, higher-than-referent levels of phosphorus (4 studies, RR = 1.20, 95% CI = 1.15-1.25), calcium (3 studies, RR = 1.10, 95% CI = 1.05-1.14), and PTH (5 studies, RR = 1.11, 95% CI = 1.07-1.16) were significantly associated with increased mortality. Although no significant associations between relatively low phosphorus or PTH and mortality were observed, a protective effect was observed for lower-than-referent calcium (RR = 0.86, 95% CI = 0.83-0.89). CONCLUSIONS: Higher-than-referent levels of PTH, calcium, and phosphorus in dialysis patients were associated with increased mortality risk in a selection of observational studies suitable for meta-analysis of non-linear relationships. Findings were less consistent for lower-than-referent values. Future analyses should incorporate the non-linear relationships between the minerals and mortality to obtain accurate effect estimates.

Predicting sagittal plane biomechanics that minimize the axial knee joint contact force during walking.

Both development and progression of knee osteoarthritis have been associated with the loading of the knee joint during walking. We are, therefore, interested in developing strategies for changing walking biomechanics to offload the knee joint without resorting to surgery. In this study, simulations of human walking were performed using a 2D bipedal forward dynamics model. A simulation generated by minimizing the metabolic cost of transport (CoT) resembled data measured from normal human walking. Three simulations targeted at minimizing the peak axial knee joint contact force instead of the CoT reduced the peak force by 12-25% and increased the CoT by 11-14%. The strategies used by the simulations were (1) reduction in gastrocnemius muscle force, (2) avoidance of knee flexion during stance, and (3) reduced stride length. Reduced gastrocnemius force resulted from a combination of changes in activation and changes in the gastrocnemius contractile component kinematics. The simulations that reduced the peak contact force avoided flexing the knee during stance when knee motion was unrestricted and adopted a shorter stride length when the simulated knee motion was penalized if it deviated from the measured human knee motion. A higher metabolic cost in an offloading gait would be detrimental for covering a long distance without fatigue but beneficial for exercise and weight loss. The predicted changes in the peak axial knee joint contact force from the simulations were consistent with estimates of the joint contact force in a human subject who emulated the predicted kinematics. The results demonstrate the potential of using muscle-actuated forward dynamics simulations to predict novel joint offloading interventions.

Pheochromocytoma - review and biochemical workup.

A commonly received question in the clinical laboratory is as follows: what is the best test for pheochromocytoma? A widely variable presentation and potentially catastrophic consequence make this a feared neoplasm despite its infrequent encounter. Because various biochemical testing modalities are available, test selection is often confusing. This selection process can be made easier through a better understanding of catecholamine producing neoplasms. The aim of this article is to provide a review of catecholamine producing neoplasms and give recommendations on appropriate test selection.

High tibiofemoral contact and muscle forces during gait are associated with radiographic knee OA progression over 3 years.

BACKGROUND: The objective of this study was to investigate differences in tibiofemoral joint contact forces between individuals with moderate medial OA who exhibit radiographic knee OA progression within 3 years versus those who do not, and to understand the relationship between model-predicted contact forces and net external moments for this population. METHODS: 27 individuals with moderate medial compartment knee OA underwent baseline instrumented gait analysis. OA progressors were defined as those who experienced at least a one grade increase in medial joint space narrowing at three years. An electromyography-driven musculoskeletal model was used to estimate muscle and tibiofemoral contact forces at baseline, which were compared between progressors and non-progressors using t-tests. RESULTS: Seven individuals experienced radiographic OA progression by 3 years. Progressors walked with significantly higher peaks of medial and total tibiofemoral contact forces, and higher impulse of medial contact forces. Significant and high correlations were found between: first peaks of medial and total contact forces with first peak of the knee adduction moment (R2 = 0.74; R2 = 0.59); second peaks of medial and total knee contact forces with second peaks of knee adduction and flexion moments (R2 = 0.71; R2 = 0.68); medial knee contact force impulse with knee adduction moment impulse (R2 = 0.76). CONCLUSIONS: Higher tibiofemoral joint contact forces during walking were associated with three-year radiographic knee OA progression based on medial joint space narrowing. These results support the need for strategies that reduce compressive knee contact forces through the reduction of adduction and flexion moments during walking.