Skull sutures

Mr. Smith is affected with Crouzon s syndrome (123500) and has craniosynostosis (i.e., premature closure of the skull sutures) along with unusual facies that includes proptosis secondary to shallow orbits, hypoplasia of the maxilla, and a prominent nose. His son and brother are also affected, although two daughters and his wife are not. Mr. and Mrs. Smith are considering having another child. Their physician counsels them that the risk that the child will be affected with Crouzon s syndrome is... 

J J (Codman, DePuy, and Mitec) United States Rivet for skull Suture anchor PLLA Drawn PLLA... 

Teflon was introduced to the public in 1960 when the first Teflon-coated muffin pans and frying pans were sold. Like many new materials, problems were encountered. Bonding to the surfaces was uncertain at first. Eventually the bonding problem was solved. Teflon is now used for many other applications including acting as a biomedical material in artificial corneas, substitute bones for nose, skull, hip, nose, and knees ear parts, heart valves, tendons, sutures, dentures, and artificial tracheas. It has also been used in the nose cones and heat shield for space vehicles and for their fuel tanks. 

Examine skull from dorsal aspect cover exoccipitals, supraoc-cipital, interparietal, frontals, nasals, nasal cartilages, zygomatic arches, and fontanelles/sutures and consider findings from ventral aspect. 

Make a 1 cm incision with a scalpel through the midline of the scalp, so that bregma and lambda (the intersection of the sagittal and lambdoid sutures) are exposed on the skull (Fig. 17.3). 

An unusual congenital malformation, the cloverleaf skull, has been associated with cocaine exposure in utero (326). In this condition, the cranium is trilobed, with severe brain deformity and hydrocephalus, because of premature fusion of the coronal and lambdoid sutures. 

Joints form the sites where bones come together or articulate. Joints are classified by the type of tissue that lies between the bones. Joints with fibrous tissue between the articulating surfaces are called fibrous joints and include the sutures of the skull. Cartilaginous joints are united by hyaline cartilage and are classified into primary and secondary cartilaginous joints. Primary cartilaginous joints do not allow any movement. 

In our work on this and other stereotaxic atlases we found the David Kopf Small Animal Stereotaxic instrument of high precision. However, no atlas or stereotaxic instrument will compensate for using bregma and lambdoid points inappropriately. These reference skull marks are the midpoints of the curve of best fit along the coronal and the lambdoid suture, respectively. They are not necessarily the points of intersection of these sutures with the midline suture. 

Fig. 3. Development of murine skull vault. (A) Schematic diagram of adult skull showing neural crest contribution in blue (after Jiang et al., 2002). (B, C) Distribution of neural crest cells at E12.5 (lateral view B) and E16.5 (dorsal view C). (D, E) Distribution of differentiated osteoblasts at E12.5 (D) and E16.5 (E). Abbreviations a, alisphenoid c, coronal suture F, frontal m, metopic (frontal) suture N, nasal nc, nasal cartilage P, parietal IP, interparietal S, squamosal SS, sagittal suture. (See Color Insert.)...

Msx2 is expressed in both the mesodermal and neural crest-derived mesenchymal cell populations that give rise to the skull vault (Jabs et al., 1993). It is also expressed in the dura, a membrane that lies between the brain and the skull vault. At later stages Msx2 is expressed in osteogenic cells within the suture (Liu et al., 1999 Rice et al., 2000). 

Expose the skull and cut along the sagittal suture from the foramen magnum to the forehead with a pair of surgical scissors (see Section 2.1.2.) the sharp pointed blade of the scissors should be placed on the inner side of the skull. 

In the infant skull accessory sutures and synchondroses can be mistaken for fractures. The most common locations for accessory sutures are intrapa-rietal, located within the parietal bone. Intraparietal accessory sutures may be unilateral or bilateral. In the acute situation, presence or absence of overlying soft tissue swelling is helpful in differentiating between fractures and accessory sutures. Sutures also tend to have less sharply defined margins and may... 

Furthermore, the analysis should include foramina and canals at the posterior and dorsal central skull base (jugular foramen, carotid canal, foramen lacerum, foramen ovale and spinosum, canalis n. hypoglossi) and as pseudofractures small sutures and canaliculi. 

The neonatal form presents as a skeletal disorder with bent bones, soft, undermineralized skull, and respiratory distress because of soft and dysplastic ribs. The infantile form can present unspecifically as poor feeding, failure to thrive, signs of rickets, flail chest and - most importantly - signs of elevated intracranial pressure. Apparently, the mineralization defect results in growth arrest of the cranial sutures ( functional craniosynostosis). In adults, mild hypophosphatasia may present as recurrent stress fractures and so-called pseudofractures (looser zones). In both children and adults, premature loss of teeth may be a sign of hypophosphatasia. 

A 3 cm long mid-sagital incision was made through the skin and galea. The periosteum was elevated and an 8-mm diameter trephine craniotomy was made inunediately proximal to the coronal suture in the parietal bone, without dural involvement. The circular cranial plates were secured to the skull and the soft tissues were closed with 4-0 Vicryl suture using simple interrupted stitches. The skin wound was closed in a standard manner with staples. 

Joints are usually divided into three classifications by composition fibrous, cartilaginous, and synovial joints. Fibrous joints (synarthroses) are connected by dense fibrous tissue. Their motions are greatly limited. Commonly, they are found in the skull. The cranial articular surfaces are irregular, yet they form specific suture match and interlock. They are joined together by fibrous tissue, which is very firm and practically fills the joint space. This type of articulation allows greater motion in infants, with gradual reduced motility with aging. 

Dr. Sutherland s study began after careful examination of a disarticulated skull. He first identified a design for motion in the structure of the sutures. After lengthy study, he concluded that motion must be the response to an involuntary mechanism. He named this mechanism the primary respiratory mechanism (PRM). 

The newborn skull has no interlocking sutures. The only fully formed joint in the cranium is that between the condyles of the occiput and the atlas. A newborn s cranial bones develop within dura, and the shape of the skull is maintained by dura, by fluid, and by the central nervous system s motion within. Developmentally before bone formation, membranes provide shape and protection and also guide and limit motion. 

The falx cerebri is a sickle-shaped arc between the two hemispheres of the brain that has three poles of attachment (Fig. 103-3). The anterior inferior pole attaches to the crista gaUi of the ethmoid. The superior pole attaches to the surface of the skull along the metopic and sagittal sutures. The posterior pole attaches to the occiput and blends into the superior surface of the tentorium in the area of the straight sinus and the internal occipital protuberance. 

FIG. 103-17 Sutures and articulations of the parietal bones of the skull, superior view. 

Another example of a genetic mutation in a lysosomal cathepsin that causes a specific human disorder has recently come to light [43]. The disease is pycnodysos-tosis which is an autosomal recessive skeletal dysplasia. Clinical features of pycno-dysostosis were first described in 1962 by Maroteaux and Lamy [60] to include bone fragility, dental abnormalities, reduced stature and skull deformities with a delay in closure of the cranial sutures. The disease experienced considerable acclaim due to the initial prediction by Maroteaux and Lamy, recently refuted [61], that this was the genetic disorder suffered by the famous French impressionist artist Toulouse-... 

Properties of materials designed with the use of silver nanoparticles, which prevent multiphcation of variotrs microorganisms, may be useful in medicine, for example. The examples are surgical retention sutures, bandages, plasters, surgical boots, medical masks, whites, skull-caps, towels, and so on. Customers know well sports clothes, prophylactic socks with antimicrobial properties. 

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