Spinal curve

To analyse the changes of women s abdominal size, spinal curve, and centre of gravity during pregnancy. 

The spino-pelvic curves take place gradualy during the acquisition of standing and walking, and further growth. The sacral ossification is belated, and when it is complete, then the sacral bone settles the undistorded part of the spinopelvic curves. The incidence remains the witness that must be the individual changing spinal curves, continuously adapted to the... 

The back should be kept straight at all times. However, a straight back does not necessarify mean a vertical back. The spinal coluttm may be inchned fi om the vertical providing the head is held up and the chin pulled in to ensure the lumbar spinal curve is flattened, thus keeping the back straight. 

The normal sagittal spinal curve changes from anterior convexity to anterior concavity and back at specific articulations C7 on Tl, T12 on LI, and L5 on the sacral base. These articulations... 

CallietR. Scoliosis. Philadelphia F.A. Davis, 1975. Fryette HH. Principles of Osteopathic Technique, Carmel, CA Academy of Applied Osteopathy, 1954. Heilig D. Some basic considerations of spinal curves. Osteopath Ana 1978 311 318. KqwmdjilA. Hiysiology d ed,... 

The five lumbar vertebrae are separated from one another by intervertebral disks. The combined unit of the vertebrae and disks, in the upright position, forms the anteroposterior lordotic lumbar spinal curve between the thoracic spine and the sacral base. 

The right and left side-bending of the lumbar spme are compared. The iliac crest that drops the greatest amount is the side opposite that to which the lumbar spine side-bends the most, or, stated another way, the side of greatest drop is the side of restricted sidebending. The spinal curve should be smooth and unimpeded. 

Human bipedal posture has made balance extremely important to musculoskeletal function. In the erect human, gravity pulls on all parts of the body. Although a column of vertebrae stacked evenly on lop of each other would have been well-balanced given little motion, anteroposterior curves developed in the spine to promote flexibility and increase strength. The transitions between spinal curves are well-suited to meet the force of gravity. Correct posture is essential to keep the force of gravity centered on those vertebrae designed for this function. 

Kyphosis is a curvature of the spine in the sagittal plane with the convexity posteriorly. A moderate degree is normal in the thoracic spine. However, an exaggeration of the curve is abnormal. Poor posture with weakened musculature is the most common cause. In this case, the shoulders slouch forward, the head drops down and forward, and the thoracic spinal curve is increased. The abdomen tends to protrude. Habit and occupation are the main offenders. 

In patients with kyphoscoliosis the severity is quantified by measuring the angle between the upper and lower portions of the spinal curve (Cobb angle). When this angle exceeds 100° (severe scoliosis), the vital capacity falls below 50% of the predicted value (48). A major factor in the pathophysiology of chronic respiratory failure in patients with kyphoscoliosis is the decrease in the compliance of the chest wall and limgs (49,50). In severe scoliosis the compliance of the chest wall may be about 25% of the predicted value. 

The large diameter A/l-afferent fibre enters the dorsal horn of the spinal cord through the medial division of the dorsal root. It then descends through the medial region of lamina I or II, or alternatively, curves around the medial (central) edge of the dorsal horn down to the ventral horn. On reaching deeper laminae, laminae IV and V, the AjS-fibres ascend back up into laminae III and IV where they repeatedly subdivide and form a characteristic termination pattern. The densest arborisation appears to occur in lamina III. Axons originating from specialised muscle stretch receptors have collaterals that pass ventrally to make monosynaptic connections with neurons of laminae V, VI and VII. Some also extend to laminae VIII and IX of the ventral horn where they synapse directly onto motor neurons and form the basis of monosynaptic reflexes. 

Fig. 6.21 Joint application of patch-clamp and voltage-clamp methods to the study of a single potassium channel present in the membrane of a spinal-cord neuron cultivated in the tissue culture. The values indicated before each curve are potential differences imposed on the membrane. The ion channel is either closed (C) or open (O). (A simplified drawing according to B. Hille)...

Those spinal radicular arteries that are radiculo-medullary arteries, supplying nerve root, pial plexus and medulla, branch in a very typical way to form the anterior spinal artery. The ascending branch continues the direction of the radicular artery in the midline of the anterior surface. The descending branch, being the larger one at thoracolumbar levels, forms a hairpin curve as soon as it reaches the midline at the entrance of the anterior fissure (Fig. 17.3). The artery runs above the vein. The maximum diameter of a spinal radiculomedullary artery or the anterior... 

Fig. 4. Dose-response correlation in cats of the effects of U-74006F on post-traumatic (compression injury) spinal cord lipid peroxidation (i.e., loss of reduced vitamin E) and on progressive white matter ischemia at 4 hours post-injury (data from ref. [24]) versus chronic (4-week) neurological recovery (data from ref. [46]). Doses indicated were administered at 30 minutes post-injury. Doses in parentheses under the chronic recovery dose-response curve indicate the total 48-hour dosing regimen that these cats received. All values are mean standard error. Numbers of animals are given in parentheses in each bar. Asterisks indicate p < 0.05 vs vehicle-injured animals by ANOVA.

There is also evidence that the neuroprotective properties of lipid-peroxidation-inhibiting doses of methylprednisolone, extensively studied in spinal-cord injury, are applicable to brain injury. The steroid has been shown to enhance the early recovery of mice subjected to a moderately severe concussive head injury when administered at 5 minutes post-injury [59], The dose-response curve for this effect is remarkably similar to that discussed above for spinal-cord injury. A 30mg/kg i.v. dose was observed to be optimal, while lower (15 mg/kg) and higher (60 and 120 mg/kg) doses were ineffective. 

To estimate effective synaptic current during repetitive firing we used a method developed for spinal motor neurons (Powers et al 1992). Synaptic current and soma-injected current add algebraically. For example, the addition of a steady synaptic current to an injected soma current causes a parallel shift in the frequency—current (f—I) curve. This implies that the faster firing rate caused by... 

Cannabinoids induce a site-specific topical antinociception to thermal stimulation (Dogrul et al. 2003 Johanek and Simone 2004 Ko and Woods 1999 Yesilyurt et al. 2003). This local antinociceptive effect synergizes with spinal cannabinoid antinociception, as reflected by a 15-fold leftward shift in the dose-response curve (Dogrul et al. 2003), and also synergizes with topical morphine antinociception (Yesilyurt et al. 2003). The latter effects were blocked by a CBIR antagonist (Yesilyurt et al. 2003). 

Ankylosing spondylitis particularly affects the iliosacral and vertebral joints which eventually become fused. Due to ossiflcation of ligaments connecting the vertebrae, the spinal column becomes curved and rotational motion is restricted. Extra-articular involvement includes conjunctivitis, psoriatic inflammation of the skin and nails and lung fibrosis. 

The data by Mudd et al. also demonstrated that ectopia lends occurred by age 6 years in 50 % of patients with Bg-unresponsive homocystinuria and by age 10 years in Bg-responsive disease [24]. Eighty-six percent of patients with homocystinuria were ascertained on the basis of ectopia lends. Finally, the time to event curves demonstrated a 50 % occurrence of radiographic spinal osteoporosis by approximately age 16 years. 

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