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T A Ribaudo

Publications and source records attributed to T A Ribaudo.

4 recordsLinked to original sources

Biomechanic effects of a contralateral shoe-lift on walking with an immobilized knee.

OBJECTIVES: A previous study demonstrated that when one knee is artificially immobilized, a contralateral shoe-lift improves the oxygen cost of walking. This study was undertaken to evaluate the kinematic and kinetic effects associated with this shoe-lift. DESIGN: Motion analysis and force platform data were collected in subjects walking (1) normally, (2) with one knee immobilized, (3) with one knee immobilized and with a one-half-inch shoe-lift applied to the contralateral, nonimmobilized shoe, and (4) with a one-inch shoe-lift similarly applied. Kinematic and kinetic data from three trials of each condition were compared graphically and statistically using a repeated measures analysis of variance. SETTING: A gait laboratory. SUBJECTS: Eight able-bodied subjects without known neurologic or musculoskeletal problems. MAIN OUTCOME MEASURES: Fifty-two peak kinematic and kinetic variables during various phases of the gait cycle. RESULTS: Statistically significant differences (p < .05) between the normal and immobilized knee conditions were noted in 22 variables; however, significant differences between the immobilized knee conditions were found in only 4 variables. There were small improvements with the shoe-lifts toward normal in peak hip abduction, hip abduction at 20% to 30% of the gait cycle, and in peak knee extension moment on the nonimmobilized side. There was a small change away from normal in peak knee extension moment on the immobilized-side for the 1" shoe-lift. CONCLUSION: Wearing a contralateral shoe-lift when one knee is immobilized is associated with only small changes in kinematic and kinetic parameters. The shoe-lift may slightly reduce the need for compensatory hip abduction and vaulting on the nonimmobilized side. Importantly, no adverse biomechanic effect from the shoe-lift was noted except for a slightly increased peak knee extension moment on the immobilized side found for the 1" but not the 1"/2 shoe-lift.

Adult↗

Three-dimensional head kinematics and cervical range of motion in the diagnosis of patients with neck trauma.

OBJECTIVE: To create a statistical model using three-dimensional (3D) head kinematics and range of motion (ROM) to distinguish between people with whiplash syndrome and asymptomatic controls. STUDY DESIGN: Cross-sectional study to estimate validity of diagnostic measures. METHODS: Fifty-one asymptomatic controls (most of whom were women), 18-35 yr old and 30 matched whiplash trauma patients seeking care from suburban outpatient clinics were sought. 3D kinematic parameters of head motion were obtained during tracking tasks (e.g., flexion, extension, etc.) and cervical ROM was measured via a head mounted inclinometer. Their level of pain and disability was assessed via a self-administered neck disability index questionnaire and visual analog pain scale (VAS). RESULTS: A scoring system of biomechanical abnormalities derived from the vertical piercing point, its second derivative and symmetry during oblique tasks. The scores ranged from a minimum of 0 to a maximum of 3. A cutoff of > or = 0.5 correctly identified the greatest number of subjects and minimized false positives (sensitivity 77%, specificity 82%, likelihood ratio 4.5). ROM performed similarly well at a cutoff of 1 SD below the normative mean (sensitivity 77%, specificity 84%, likelihood ratio 3.9). CONCLUSIONS: There is potential for biomechanical analysis to objectively detect abnormalities. The statistical model yielded moderate to high sensitivity and specificity using 3D helical-axis parameters of the head and standard ROM. The model development will continue via this process in future studies. These data could be a first step toward the creation of useful, noninvasive protocols for the diagnosis and management of soft tissue trauma of the neck.

Adolescent↗

A tool to assess biomechanical gait efficiency; a preliminary clinical study.

A goal of many physiatric interventions is to improve biomechanical walking efficiency. Thus, a tool that helps assess this efficiency, independent of cardiac, pulmonary, psychologic, or other nonbiomechanical factors, would be useful. Currently used methods to measure efficiency, including comfortable walking speed, are not specific to biomechanical variables. A potential tool, the biomechanical efficiency quotient (BEQ), which uses three variables--average stride length, vertical displacement of the trunk during walking, and sacral height during standing--is proposed and preliminarily tested. This quotient is based on Saunders, Inman, and Eberhart's theories and on a prior study in able-bodied subjects. The BEQ was computed in 20 consecutive patients with neurologically based gait disability referred for gait laboratory evaluation who subjectively reported that one or two ankle-foot-orthoses (AFOs) reduced the effort necessary to walk. The quotient was calculated with and without the AFO(s) by dividing the average vertical displacement of the sacrum, which was measured with an optoelectronic system, and by a predicted displacement, which was based on the patient's sacral height and average stride length. The mean BEQ with the AFO(s) (6.3 +/- 4.4) was significantly less than the mean BEQ without the AFO(s) (9.7 +/- 7.1); P = 0.005. Furthermore, the BEQ was less with the AFO(s) compared with trials without the AFO(s) in all subjects. Percent change in BEQ with the AFO(s) (26.8 +/- 19.6) correlated with percent change in comfortable walking velocity (24.8 +/- 31.8), r = 0.73, P<0.001, across all subjects. The BEQ may be useful in specifically assessing the effect on biomechanical efficiency of physiatric interventions, despite variable nonbiomechnical factors. An instrument to measure vertical trunk displacement during walking outside of the gait laboratory would be extremely useful for further necessary longitudinal studies.

Adult↗