Biomechanical response to ladder slipping events: Effects of hand placement.

Ladder falling accidents are a significant, growing and severe occupational hazard. The factors that contribute to falls from ladders and specifically those that influence the motor response from ladder falls are not well understood. The aims of this research were to determine the effects of hand placement (rung versus rail) on muscle activation onset and peak activity timing in response to slipping on a ladder and to sequence the timing of events following slip initiation.

Biomechanics of Lower Limbs during Walking among Candidates for Total Knee Arthroplasty with and without Low Back Pain.

The effect of joint pathologies, such as unilateral knee osteoarthritis (UKOA) or low back pain (LBP), on bilateral gait symmetry has gained increased attention during the past decade. This study is the first to compare gait patterns between patients with UKOA and LBP in combination and with UKOA only. Temporal, kinematic, and kinetic variables were measured bilaterally during gait stance phase in 31 subjects with UKOA and LBP (Group I) and 11 subjects with only UKOA (Group II).

Effects of foot placement, hand positioning, age and climbing biodynamics on ladder slip outcomes.

Ladder falls frequently cause severe injuries; yet the factors that influence ladder slips/falls are not well understood. This study aimed to quantify (1) the effects of restricted foot placement, hand positioning, climbing direction and age on slip outcomes, and (2) differences in climbing styles leading to slips versus styles leading to non-slips. Thirty-two occupational ladder users from three age groups (18-24, 25-44 and 45-64 years) were unexpectedly slipped climbing a vertical ladder, while being assigned to different foot placement conditions (unrestricted vs.

A retrospective study of the relationship between back pain and unilateral knee osteoarthritis in candidates for total knee arthroplasty.

The purpose of this study was to determine the presence and temporal relationship between back pain and knee osteoarthritis (OA). All subjects were candidates for unilateral total knee arthroplasty (TKA) to relieve knee pain related to OA, and information regarding the prevalence of back pain was collected via questionnaires. A total of 42 subjects with unilateral knee OA responded to the questionnaires, and 74% of subjects reported chronic back pain, which first occurred approximately 10 years before their becoming candidates for TKA.

Symmetry of ground reaction forces and muscle activity in asymptomatic subjects during walking, sit-to-stand, and stand-to-sit tasks.

In addition to walking, essential activities of daily living include the ability to rise from a seated position and sit from a standing position. Although many high-quality studies have been performed on these common functional tasks, the objective of the current research is to quantify symmetry indices (SI) of ground reaction force (GRF) and electromyographical (EMG) variables between the non-dominant (ND) and dominant (D) sides of the body in asymptomatic subjects during walking, sit-to-stand, and stand-to-sit tasks. Thirty-five healthy subjects consented to participate in the study that included collection of bilateral GRF and muscle activity of the back, trunk, and legs during the stance phase of walking and sit-stand tasks.

Effect of orientation on measured failure strengths of thoracic and lumbar spine segments.

Substantial research has been performed over many years to determine the compressive failure limits of spinal motion segments. However, the majority of studies have not considered the natural alignment of the spine, testing only for pure compression loads. This study tested 27 motion segments, ranging from the T6/T7 to L4/L5 levels, from 13 human cadaveric spines.