Clinical biomechanics
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Clinical biomechanics · Mar 2017
Comparative StudyIs pelvic fixation the only option to provide additional stability to the sacral anchorage in long lumbar instrumentation? A comparative biomechanical study of new techniques.
Supplementary iliac screws have the highest potential to protect S1-pedicle-screws from loosening in long fusion constructs. However, this technique bridges the iliosacral joint with potential disadvantages for the patient. This study aimed to evaluate if two different established fixation techniques can be used in addition to pedicle screws as alternative to iliac screws, and if these two techniques can provide similar stability when S1-pedicle-screws are loosened. ⋯ In long lumbar pedicle screw instrumentations including L5/S1, additional ilium screws have the highest potential to protect the S1-anchorage. Additional L5/S1-translaminar-screws can increase stability of the lumbosacral junction without bridging the iliosacral joint, whereas lamina hooks showed no significant biomechanical benefit.
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Clinical biomechanics · Feb 2017
ReviewGait deviations associated with plantar heel pain: A systematic review.
Plantar heel pain is a common foot disorder associated with significant pain and gait-related disability. The aim of this systematic review was to identify gait deviations associated with plantar heel pain. ⋯ Studies included in this review identified specific foot and ankle gait deviations in individuals with plantar heel pain compared to asymptomatic cases or limbs. The variables identified in this review may be used to assist in identifying movement-related gait dysfunction for treatment decisions or as outcome measures of recovery. Additional research is needed to increase confidence and clinical relevance of gait variables used to assess and treat individuals with PHP.
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Clinical biomechanics · Feb 2017
Comparative StudyAnalysis of the upper cervical spine stiffness during axial rotation: A comparative study among patients with tension-type headache or migraine and asymptomatic subjects.
Many studies reported the implication of the cervical musculoskeletal system in patients with tension type headache and migraine. The objective of this study is to investigate the upper cervical spine stiffness features in axial rotation among headache patients in comparison with a healthy population. ⋯ Stiffness seems not to be altered among tension type headache and migraine patients. However, patients seem prone to display a larger right-left asymmetry of axial rotation and a reduction in the motion range tolerance, emphasizing the likely link between the cervical discomfort and these pathologies. Any difference is observed in the elastic behavior of the upper cervical spine between the two primary headache populations. However, further investigations are needed to confirm these previous results taking various specific clinical characteristics into consideration.
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Clinical biomechanics · Feb 2017
The role of lesser trochanter fragment in unstable pertrochanteric A2 proximal femur fractures - is refixation of the lesser trochanter worth the effort?
Instability of osteoporotic pertrochanteric fractures is defined by loss of medial/lateral cortical integrity with the posteromedial fragment including the lesser trochanter being pivotal for load distribution. Literature addressing the importance of lesser trochanter refixation is scarce. To clarify the effect of lesser trochanter refixation on primary stability in these fractures, following study was performed. ⋯ Refixation of the lesser trochanter may increase the primary stability of pertrochanteric fracture osteosynthesis as all groups showed a higher primary stability. Therefore, refixation should be considered in unstable, osteoporotic fractures. If additional trauma through refixation appears inappropriate, cement augmentation should be performed as it showed only 9% less stability than a non-augmented proximal femoral nail with refixation of the lesser trochanter.
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Clinical biomechanics · Jan 2017
Influence of different sizes of composite femora on the biomechanical behavior of cementless hip prosthesis.
For the biomechanical evaluation of cementless stems different sizes of composite femurs have been used in the literature. However, the impact of different specimen sizes on test results is unknown. ⋯ Specimen size seems to be a minor influence factor for biomechanical evaluation of cementless stems. However, the small composite femur is less suitable for biomechanical testing since this size failed under physiological adapted loads. For the CLS Spotorno osseous integration is unlikely at the tip of the stem and the tendency for stress shielding is the highest at the level of the lesser trochanter.