The findings indicate that, in community-dwelling older people, STS performance is influenced by multiple physiological and psychological processes and represents a particular transfer skill, rather than a proxy measure of lower limb strength.

Background Common lower limb postures have been found when noncontact anterior cruciate ligament (ACL) injuries occur during sidestep cutting tasks. These same postures have been linked to knee loadings known to stress the ACL. Hypothesis Whole body technique modification would reduce knee loading. Study Design Controlled laboratory study. Methods Experienced team sport athletes were recruited for whole body sidestep cutting technique modification. Before and after a 6-week technique modification training, participants performed sidestep cutting tasks while ground-reaction force and motion data were collected. A kinematic and inverse dynamics model was used to calculate 3-dimensional knee loading during sidestep cutting. Results At initial foot contact, the participants placed their stance foot closer to the body’s midline and held their torso more upright, in line with the aims of the technique modification training. This was accompanied by significantly lower peak valgus moments in the weight acceptance phase of stance. Both postural changes were correlated with the change in peak valgus moment. Conclusion Whole body sidestep cutting technique modification resulted in reduced knee loading. Clinical Relevance Implementation of whole body technique modification may produce effective ACL injury prevention programs in sports involving sidestep cutting.

Technique and knee loads in sidestep cutting 2 Abstract Purpose: To identify the effect of modifying sidestep cutting technique on knee loads and predict what impact such change would have on the risk of non-contact anterior cruciate ligament injury. Methods: A force platform and motion analysis system were used to record ground reaction forces and track the trajectories of markers on 15 healthy males performing sidestep cutting tasks using their normal technique and nine different imposed techniques. A kinematic and inverse dynamic model was used to calculate the three dimensional knee postures and moments. Results: The imposed techniques of foot wide, torso leaning in the opposite direction to the cut resulted in increased peak valgus moments experienced in weight acceptance. Higher peak internal rotation moments were found for the foot wide and torso rotation in the opposite direction to the cut techniques. The foot rotated in technique resulted in lower mean flexion/extension moments while the foot wide condition resulted in higher mean flexion/extension moments. The flexed knee, torso rotated in the opposite direction to the cut and torso leaning in the same direction as the cut techniques had significantly more knee flexion at heel strike. Conclusion: Sidestep cutting technique had a significant effect on loads experienced at the knee. The techniques which produced higher valgus and internal rotation moments at the knee, such as foot wide, torso leaning in the opposite direction to the cut and torso rotating in the opposite direction to the cut, may place an athlete at higher risk of injury as these knee loads have been shown to increase the strain on the anterior cruciate ligament. Training athletes to avoid such body positions may result in a reduced risk of non-contact anterior cruciate ligament injures.

MICKLE, KAREN J., JULIE R. STEELE, AND BRIDGET J. MUNRO. The feet of overweight and obese young children: are they flat or fat ? Obesity. 2006;14:1949-1953. Objective: The purpose of this study was to determine whether the flat feet displayed by young obese and overweight children are attributable to the presence of a thicker midfoot plantar fat pad or a lowering of the longitudinal arch relative to that in non-overweight children. Research Methods and Procedures: Foot anthropometry, an arch index derived from plantar footprints, and midfoot plantar fat pad thickness measured by ultrasound were obtained for 19 overweight/obese preschool children (mean age, 4.3 Ϯ 0.9 years; mean height, 1.07 Ϯ 0.1 m; mean BMI, 18.6 Ϯ 1.2 kg/m 2 ) and 19 non-overweight children matched for age, height, and sex (mean age, 4.3 Ϯ 0.7 years; mean height, 1.05 Ϯ 0.1 m; mean BMI, 15.7 Ϯ 0.7 kg/m 2 ). Results: Independent t tests revealed no significant between-subject group differences (p ϭ 0.39) in the thickness of the midfoot plantar fat pad. However, the overweight/ obese children had a significantly lower plantar arch height (0.9 Ϯ 0.3 cm) than their non-overweight counterparts (1.1 Ϯ 0.2 cm; p ϭ 0.04). Discussion: The lower plantar arch height found in the overweight/obese children suggests that the flatter feet characteristic of overweight/obese preschool children may be caused by structural changes in their foot anatomy. It is postulated that these structural changes, which may adversely affect the functional capacity of the medial longitudinal arch, might be exacerbated if excess weight bearing continues throughout childhood and into adulthood.

The individualized intervention program reduced some falls risk factors but did not prevent falls. The lack of an effect on falls may reflect insufficient targeting of the intervention to an at-risk group.