Clinical biomechanics
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Clinical biomechanics · Jun 2002
Examination of the flexion relaxation phenomenon in erector spinae muscles during short duration slumped sitting.
The purpose of this study was to examine the myoelectric activity of the erector spinae muscles of the back in order to determine if the flexion relaxation phenomenon occurs in seated forward flexion or slumped postures. ⋯ Examination of flexion relaxation during seated postures may provide insight into the association between low back pain and seated work.
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Clinical biomechanics · May 2002
Comparative StudyM-mode ultrasound: a reliable measure of transversus abdominis thickness?
The purpose of this study was to establish a reliable method for measuring transversus abdominis thickness in asymptomatic human subjects in supine lying, standing and walking. ⋯ This procedure has the potential to detect dysfunctional changes in abdominal muscle activity for patients with low back pain in a functional setting.
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Clinical biomechanics · Jan 2002
Comparative StudySagittal plane segmental motion of the cervical spine. A new precision measurement protocol and normal motion data of healthy adults.
(1) Precise documentation of sagittal plane segmental rotational and posteroanterior translational motion of segments C0/C1-C6/C7 of the human cervical spine from lateral radiographic views. (2) Compilation of a database describing normal motion. (3) Comparison of individual motion patterns with the normal database. ⋯ Flexion-extension radiographs of the cervical spine are performed to explore potential damage to the bony or ligamentous structure resulting in abnormal, segmental motion patterns. Determining rotational motion gives only an incomplete picture. The new protocol allows for precise quantification of translational motion and classification of segments as hypo- or hypermobile by comparison with normal motion data.
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Clinical biomechanics · Dec 2001
Lower extremity kinetics during stair ambulation in patients with and without patellofemoral pain.
To compare lower extremity kinetics during stair ascent and descent in subjects with and without patellofemoral pain. ⋯ Subjects with patellofemoral pain had reduced peak knee extensor moments, suggesting that quadriceps avoidance was employed to reduce patellofemoral joint reaction forces. The lack of group differences in peak moments at the hip and ankle suggests that secondary compensation did not occur exclusively at the hip or ankle in this group of subjects with patellofemoral pain. RELEVANCE STATEMENT: Because stair ambulation is often used to evaluate the reproducibility of symptoms and to identify abnormal movement patterns indicative of patellofemoral pain, knowledge of lower extremity mechanics during stair negotiation is necessary to better characterize compensatory behavior in this population.
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Clinical biomechanics · Jun 2001
A computer model to simulate patellar biomechanics following total knee replacement: the effects of femoral component alignment.
The objective of this study is to analyze the biomechanics of the patellar component following total knee replacement. More specifically we investigated the effect of displacing the femoral component of an Insall-Burstein II total knee replacement on the patellar tracking and patello-femoral contact pressures. ⋯ Precise alignment of the prosthetic components is difficult to control during total knee replacement due to the lack of precise anatomical landmarks in the human knee joint. Consequently, the position of each prosthetic component may differ from the ideal one suggested by the manufacturer. Improper alignment of the prosthetic components during total knee replacement may lead to premature implant failure.