Mary Lou Bareither

Task-specific Training Reduces Trip-related Fall Risk in Women

PURPOSE The potential of task-specific training as a fall-prevention intervention was studied. The primary purpose of the study was to determine the extent to which a task-specific training protocol decreased the number of falls by middle-age and older women after a laboratory-induced trip. Secondary purposes were to explore the ability of trunk kinematics during the initial recovery step and the length of the initial recovery step to correctly classify the trip outcome and to quantify the extent to which the training protocol affected these variables. METHODS Healthy community-dwelling women (n = 52) were assigned to either a training group or a control group that received no training. Training group women participated in an individually tailored, task-specific training protocol during which forward-directed stepping responses were necessary to avoid a fall after treadmill-delivered postural disturbances. Following the protocol, the ability to avoid a fall after a laboratory-induced trip was assessed. The primary outcome variable was the success (recover) or failure (fall) of the posttrip stepping response. RESULTS Compared with the control group, there were fewer falls by the trained women after the laboratory-induced trip (P < 0.001; odds ratio = 0.13). Using logistic regression, falls and recoveries after the trip were sensitively classified by trunk flexion angle at the completion of the initial recovery step and the length of the initial recovery step (sensitivity = 0.67, specificity = 0.98), the former of which improved as a result of the task-specific training protocol. CONCLUSIONS The task-specific training protocol significantly reduced the number of falls after a laboratory-induced trip. Prospective study is required to determine whether this task-specific training reduces falls in the community and, consequently, may complement currently used exercise-based fall prevention intervention methods.

Modifiable performance domain risk-factors associated with slip-related falls

Falls are a major source of injury in older adults. Many falls occur after slipping. This study determined performance-related factors that both contribute to slip-related falls and that may be effectively and efficiently modified through targeted intervention. Thirty-five young adults and 21 healthy older adults (age: 70.9+/-5.1 years) were slipped in a laboratory using a slippery surface. The biomechanics of the 18 older adults who fell and the 30 younger adults who recovered following slips were analyzed. A set of potentially modifiable variables, initially based on significant between-groups differences, was further analyzed using stepwise discriminant analysis and logistic regression. The discriminant analysis correctly categorized 93.8% of the falls and recoveries based on two variables; the velocity of the slipping foot relative to the velocity of the whole body center of mass (COM), and the lateral placement of the recovery foot relative to the COM. The logistic regression determined the expected change in the odds of a recovery following a slip given a hypothesized intervention-induced improvement of these variables. Decreased velocity of the slipping foot relative to the COM, or decreased lateral placement of the recovery foot relative to the COM to zero, increased the odds of recovery by 17% and 27%, respectively. This suggests that intervention targeted at improving these specific lower extremity control variables following the onset of a slip has the potential to significantly decrease slip-related fall risk.

In vivo loading model to examine bone adaptation in humans: A pilot study

Bone is typically well suited for its habitual loading environment because of its ability to adapt. Although characteristics of the mechanical loading environment predict the bone adaptive response in animals, this has not been prospectively validated in humans. Here, we describe an in vivo loading model in which women apply forces to the radius by leaning onto their hand. We characterized the strain environment imposed on the radius using cadaveric experimentation and conducted a prospective study in which 19 adult women loaded their distal radii 50 cycles/day, 3 days/week, for 28 weeks and seven additional adult women served as controls. In four cadaveric specimens, loading caused compressive principal strains of −1,695 ± 396 μϵ with radial bending dorsally and towards the ulna. Prospective in vivo loading produced measurable improvements to bone and appeared to protect against bone loss associated with seasonal fluctuations in physical activity and sun exposure. Experimental subjects had significant gains to bone volume (BV) and moments of inertia, while, control subjects had significant losses in BMC and moments of inertia. The loading model is thus suitable as a model system for exploring bone adaptation in humans, and may eventually be clinically useful for strengthening the radius of women.

Clay Modeling versus Written Modules as Effective Interventions in Understanding Human Anatomy.

The effectiveness of clay modeling to written modules is examined to determine the degree of improvement in learning and retention of anatomical 3D relationships among students with different learning preferences. Thirty‐nine undergraduate students enrolled in a cadaver dissection course completed a pre‐assessment examination and the VARK questionnaire, classifying learning preference as visual, auditory, read/write, or kinesthetic. Students were divided into clay, module, and control groups with preference for learning style distributed among groups. The clay and module groups participated in weekly one‐hour classes using either clay models or answering written questions (modules) about anatomical relationships, respectively. The control group received no intervention. Post‐assessment and retention examinations were administered at the end of the semester, and three months later, respectively. Two variables (Δ1, Δ2) represented examination score differences between pre‐ and post‐assessment and between post‐assessment and retention examinations, respectively. The Δ1 for clay and module groups were each significantly higher than controls (21.46 ± 8.2 vs. 15.70 ± 7.5, P ≤ 0.05; and 21.31 ± 6.9 vs. 15.70 ± 7.5, P ≤0.05, respectively). The Δ2 for clay and module groups approached but did not achieve significance over controls (−6.09 ± 5.07 vs. −8.80 ± 4.60, P = 0.16 and −5.73 ± 4.47 vs. −8.80 ± 4.60, P = 0.12, respectively). No significant differences were seen between interventions or learning preferences in any group. However, students of some learning styles tended to perform better when engaging in certain modalities. Multiple teaching modalities may accommodate learning preferences and improve understanding of anatomy. Anat Sci Educ.

Habitual site-specific upper extremity loading is associated with increased bone mineral of the ultradistal radius in young women

INTRODUCTION Osteoporosis and osteopenia are major contributors to the high incidence of fractures in older women. Habitual loading plays a crucial role in the acquisition and maintenance of bone. It may be possible to develop clinical interventions based on targeted modes of physical loading that can improve bone health and reduce fractures in women. If so, an important first step is determining the degree to which common fracture sites, such as the distal radius are responsive to habitual loading. METHODS The bone mineral density (BMD) and bone mineral content (BMC) of the ultradistal radius of 15 female gymnasts were compared with those of an age-matched, mass-matched, and height-matched control group. The hypothesis that the ultradistal radius BMD and BMC in gymnasts would be higher than those of the control group was tested using a 2 x 2 (left/right x group) repeated measures analysis of variance (MANOVA). RESULTS After adjusting for the between-group difference in the influence of body mass, the gymnasts had 24% larger BMD and a 34% larger BMC at the ultradistal radii than the control group (p < 0.001). CONCLUSIONS These results suggest that the ultradistal radius is responsive to the types and magnitudes of load encountered during gymnastics. A responsive distal radius is a necessary prerequisite to the development of loading-based interventions to increase ultradistal radius bone quality. Such interventions have the potential to significantly increase distal radius strength, thereby reducing the incidence of fracture.

Stance Quantified in Real World Scenario: Changes in Knee Joint Kinematic between Shod and Barefoot Running

Background: Barefoot running has been reported to cause favorable biomechanical changes during running. However, knee joint kinematics changes in stance phase during different running conditions in out of laboratory setup has not be explored. The aim of this study was to evaluate three dimensional changes in knee kinematics among habitual shod runners outside of gait laboratory during shod and barefoot running. Methods: Using unobtrusive body-worn sensors mounted to anatomical segments, kinematic data were acquired in twelve healthy young individuals (Age 22.5 ± 2.2 years, BMI 21.4 ± 2 Kg/m2). Several kinematic parameters were compared between shod and barefoot running including three dimensional knee joint range of motion, tibia internalexternal rotation, knee medial-lateral impact, stride time, flight time, contact time and shock propagation time. Results: With no significant difference (p=0.21) in running speed between the two trial conditions, significant reduction (6.4%, p=0.005) in flexion-extension range and increase (8.4%, p=0.0001) in internal-external rotation range of knee joint was observed from barefoot running. The knee joint Varus-valgus range of motion and impact was not influenced (p=0.88) by running condition. A significant increase of tibia rotation, shock transmission time (27%) from tibia to sacrum was observed (p=0.009) along with changes in gait cycle time and flight time (p<0.05). Conclusion: The current study using body-worn sensors explored three dimensional changes in knee joint kinematics during stance phase under different running conditions in an out of laboratory environment. The results suggest that in habitual shod runners transiting to barefoot running can have negative impact from significant increase in range of internal-external rotation of knee joint and tibia. Future research studies are warranted in a larger sample size to confirm the findings.

Benefit of footwear in knee joint stabilisation during overground running

Benefit of footwear in knee joint stabilisation during overground running Gurtej Grewal, Matthew Walthers, Jacqueline Lee-Eng, Mary Lou Bareither and Bijan Najafi* University of Arizona, College of Medicine, PO Box 245072, 1501 N Campbell Avenue, R 7342, Tucson, 85724-5072 United States; University of Illinois at Chicago, Kinesiology, Chicago, 60616 United States; University of Illinois at Chicago, Department of Physical Therapy, Chicago, United States; University of Arizona, College of Medicine, Surgery, interdisciplinary Consortium on Advanced Motion Performance (iCAMP), PO Box 245072, 1501 N Campbell Avenue, R 7342, PO Box 245072, Tucson, 85724-5072 United States