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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.

Background Ankle-foot orthoses (AFOs) are commonly prescribed during rehabilitation after limb salvage. AFO stiffness is selected to help mitigate gait deficiencies. A new custom dynamic AFO, the Intrepid Dynamic Exoskeletal Orthosis (IDEO), is available to injured service members but prescription guidelines are limited. Questions/purposes In this study we ask (1) does dynamic AFO stiffness affect gait parameters such as joint angles, moments, and powers; and (2) can a given dynamic AFO stiffness normalize gait mechanics to noninjured control subjects? Methods Thirteen patients with lower limb salvage (ankle arthrodesis, neuropathy, foot/ankle reconstruction, etc) after major lower extremity trauma and 13 control subjects who had no lower extremity trauma and wore no orthosis underwent gait analysis at a standardized speed. Patients wore their custom IDEO with posterior struts of three different stiffnesses: nominal (clinically prescribed stiffness), compliant (20% less stiff), and stiff (20% stiffer). Joint angles, moments, powers, and ground reaction forces were compared across the varying stiffnesses of the orthoses tested and between the patient and control groups. Results An increase in AFO compliance resulted in 20% to 26% less knee flexion relative to the nominal (p = 0.003) and stiff (p = 0.001) conditions, respectively. Ankle range of motion and power generation were, on average, 56% (p \ 0.001) and 63% (p \ 0.001), respectively, less than controls as a result of the relatively fixed ankle position. Conclusions Patients with limb salvage readily adapted to different dynamic AFO stiffnesses and demonstrated few Support was provided by

Selective laser sintering (SLS) is a well-suited additive manufacturing technique for generating subject-specific passive-dynamic ankle-foot orthoses (PD-AFOs). However, the mechanical properties of SLS PD-AFOs may differ from those of commonly prescribed carbon fiber (CF) PD-AFOs. Therefore, the goal of this study was to determine if biomechanical measures during gait differ between CF and stiffness-matched SLS PD-AFOs. Subject-specific SLS PD-AFOs were manufactured for ten subjects with unilateral lower-limb impairments. Minimal differences in gait performance occurred when subjects used the SLS versus CF PD-AFOs. These results support the use of SLS PD-AFOs to study the effects of altering design characteristics on gait performance.

Objective. To determine the longitudinal impact of integrating health literacy and cultural competency content throughout the professional pharmacy curriculum and the impact of additional changes made to the curriculum based on the results of a longitudinal analysis. Methods. Health literacy and cultural competency concepts were integrated throughout a four-year professional pharmacy curriculum. A cohort of students were assessed using health literacy and cultural competency survey instruments at baseline, the end of the fall semester of the first professional (P1) year, and the end of each subsequent academic year. From the four-year assessment, a need for additional reinforcement in the spring P1 semester was identified, so a health literacy activity was incorporated into an introductory pharmacy practice experience (IPPE) for two cohorts of students. The outcomes were compared to those of a single cohort of students who had completed their P1 year prior to integration of the additional content. A health literacy survey instrument was given at the beginning and after completion of the semester to assess change. Preceptors also completed a brief survey. Results. Curricular integration improved health literacy and cultural competency attitudes and selfperceived ability in P1 students, as assessed by the instruments. However, declines in students' health literacy and cultural competency were identified when the students were retested in the spring semester. After implementing the health literacy IPPE activity, the health literacy scores of P1 students in the two subsequent years improved. Preceptors also gave positive feedback on the utility of this activity. Conclusion.Integrating health literacy and cultural competency content throughout the curriculum resulted in improvement in students' scores in these areas from the first to the fourth professional year, but when there were no integrated activities, scores dropped. Implementing additional activities improved student-perceived HL skills. Thus, it may be important to ensure there is inclusion of content in each semester of the curriculum to maximize effects.

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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.

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