ABSTRACT
<p><b>BACKGROUND</b>A quantitative and accurate measurement of the range of hip joint flexion (RHF) is necessarily required in the evaluation of disordered or artificial hip joint function. This study aimed to assess a novel method to measure RHF more accurately and objectively.</p><p><b>METHODS</b>Lateral radiographs were taken of 31 supine men with hip joints extended or flexed. Relevant angles were measured directly from the radiographs. The change in the sacrofemoral angle (SFA) (the angle formed between the axis of the femur and the line tangent to the upper endplate of S1) from hip joint extension to hip joint flexion, was proposed as the RHF. The validity of this method was assessed via concomitant measurements of changes in the femur-horizontal angle (between the axis of the femur and the horizontal line) and the sacrum-horizontal angle (SHA) (between the line tangent to the upper endplate of S1 and the horizontal line), the difference of which should equal the change in the SFA.</p><p><b>RESULTS</b>The mean change in the SFA was 112.5 ± 7.4°, and was independent of participant age, height, weight, or body mass index. The mean changes in the femur-horizontal and SHAs were 123.0 ± 6.4° and 11.4 ± 3.0°, respectively. This confirmed that the change of SFA between hip joint extension and hip joint flexion was equal to the difference between the changes in the femur-horizontal and SHAs.</p><p><b>CONCLUSIONS</b>Using the SFA, to evaluate RHF could prevent compromised measurements due to the movements of pelvis and lumbar spine during hip flexion, and is, therefore, a more accurate and objective method with reasonable reliability and validity.</p>
Subject(s)
Adult , Humans , Male , Young Adult , Hip Joint , Diagnostic Imaging , General Surgery , Radiography , Range of Motion, Articular , Physiology , Sacrum , Diagnostic Imaging , General SurgeryABSTRACT
AMPARs are excitatory glutamate receptors that mediate the fast synaptic transmission. AMPARs are homo- or hetero-tetramers composed of selective combinations of four subunits: GluR1, GluR2, GluR3 and GluR4. AMPARs containing GluR2 are mainly in the central nervous system and are Ca2+ impermeable. MPARs-lacking GluR2 are Ca2+ permeable, and GluR2-lacking AMPARs are confined to certain neurons or certain physiological or pathological conditions. Recent research showed that GluR2-lacking AMPARs play special roles in the synaptic function and plasticity and transduction of local signal transduction. This paper reviews the GluR2-lacking AMPARs and their roles in the synaptic function and plasticity.
ABSTRACT
Posterior pedicle fixation-based dynamic stabilization is now densely studied in the non-fusion spine surgery. The method is characterized by the motion preservation of segmental lumbar, avoidance of the stress change after fusion surgery, and adjacent disc degeneration. Posterior pedicle fixation-based dynamic stabilization systems have undergone fast development and are now used for the treatment of degenerative lumbar spine disease. As an innovation of traditional fusion surgery, the clinical evaluation of its efficacy has become a focus of study among spine surgeons. In this paper, we review the recent progress in the clinical efficacy of posterior pedicle fixation-based dynamic stabilization.