Clinical biomechanics
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Clinical biomechanics · Feb 2010
Comparative StudyComparison of trunk stiffness provided by different design characteristics of lumbosacral orthoses.
Lumbosacral orthoses (LSOs) are class I medical devices that are used in conservative and postoperative management of low back pain. The effectiveness of LSOs depends on their design aimed at enhancing trunk stiffness. Therefore, the purpose of this study was to compare two lumbar supports: extensible (made of neoprene and lycra) and non-extensible (made of polyester and nylon). ⋯ A non-extensible LSO is more effective in augmenting trunk stiffness and limiting trunk motion following a perturbation than an extensible LSO. The rigid front panels do not provide any additional trunk stiffness most likely due to incongruence created between the body and a brace.
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Clinical biomechanics · Jan 2010
Lumbar extraforaminal ligaments act as a traction relief and prevent spinal nerve compression.
In a previous study, ligaments that connect the extraforaminal lumbar spinal nerves with the fibrous capsule of the facet joints and the dorsolateral side of the intervertebral disc were described. This anatomical configuration suggests a mechanical role in transferring extraforaminal spinal nerve traction. ⋯ Extraforaminal ligaments play an important role in the prevention of damage due to spinal nerve traction. The proximal attachments secure a spinal nerve position central in the intervertebral foramen and also reduce longitudinal tension.
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Clinical biomechanics · Oct 2009
Comparative StudyReconstruction interlocking nails for ipsilateral femoral neck and shaft fractures: biomechanical analysis of effect of supplementary cannulated screw on intracapsular femoral neck fracture.
To stabilize the femoral head in ipsilateral femoral neck and shaft fractures, one cannulated screw was supplemented in front of the reconstruction interlocking nail (recon nail). ⋯ From the biomechanical viewpoint, the subcapital fractures in combined fractures are recommended to supplement with one cannulated screw in front of the recon nails to eliminate complications associated with stabilization.
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Clinical biomechanics · Oct 2009
In vitro quantitative assessment of total and bipolar shoulder arthroplasties: a biomechanical study using human cadaver shoulders.
Glenohumeral arthroplasty has produced results far inferior to those seen with hip and knee joint procedures. Therefore, the objective of this study was to evaluate the biomechanical parameters of the glenohumeral joint before and after total shoulder arthroplasty and bipolar hemiarthroplasty in 12 different positions simulating overhead activities. ⋯ The alterations in joint reaction force, contact pressure and contact patterns following shoulder arthroplasty suggest a possible etiology for glenoid component edge loading in patients following total shoulder arthroplasty. This edge loading may lead to a rocking phenomenon of the glenoid component and subsequent loosening.
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Clinical biomechanics · Oct 2009
Tibiofemoral contact mechanics with a femoral resurfacing prosthesis and a non-functional meniscus.
Increased contact stress with a femoral resurfacing prosthesis implanted in the medial femoral condyle and a non-functional meniscus is of concern for potential deleterious effects on tibiofemoral contact mechanics. ⋯ Although the condition of a meniscal tear without the resurfacing device could not be compared, possible effects of reduced meniscal tissue and biomechanical integrity of the meniscus must be considered in an in vivo application.