Bone injury

Bone health, vitamin K and, 17 655 Bone injuries, superelastic and... 

Indeed, in a case-control study of 124 655 individuals who suffered a bone fracture matched with 373 962 subjects who had not had any bone injury, the relative risk of a bone fracture was significantly lower in those who took lithium, both before and after correction for psychotropic drug use (OR = 0.67 95% Cl = 0.55, 0.81) (424). 

Eventually, physicians developed ways to treat broken bones as evidenced by ancient Egyptian hieroglyphics depicting injured limbs wrapped and braced to heal normally. As wars were waged on a larger scale and weaponry became more efficient and deadly, fractures and other bone injuries became more prominent. 

A 40-year-old woman had multiple bone injuries, severe sepsis, and coma after a car accident a retroperitoneal hematoma caused by lumbar fractures was drained, but she continued to be pyrexial (23). She had prominent accumulation of Ga, which had been used for bone scanning, in her multiple recent fractures and an area of accumulation in the soft tissue related to a fractured vertebra. Post-traumatic paravertebral calcifications had accumulated Ga and simulated the presence of an infected hematoma. 

The condition in orthopedics known as nonunion is one of the most serious encountered in the field of bone injury. A fracture, often for reasons unknown but probably related to bad circulation, just doesn t heal. The ends of the fracture don t join together, leaving the patient with a serious disability in essence, a permanent fracture. If this were to happen in one of the large bones of the leg or arm, it would be very debilitating and lead to permanent crippling. There is nothing that an orthopedist dreads more than a nonunion. 

Potential applications of this device are to be found in medicine, dentistry and areas of industry. The most obvious promise of this unique unit is in medical or dental emergencies and other field use where a quick fluoroscopic examination is desired such as, (1) examination of a football player s possible bone injury on the football field (2) root canal analysis and possible monitoring of surgical procedures and (3) industrial detection of welding defects or gas leaks in pipes. 

In cases of long bone injury in man and the rat, Cuthbertson and his colleagues have shown that the protein metabolic response to injury is considerably reduced by exposure to 30°C (C4a, C5, C40) short-term thermoregulatory adaptation did not seem to be involved. 

Calhoun NR, Campbell S, Smith JC. 1970. Accumulation of labeled zinc, strontium, and calcium in bone injuries. J Dent Res 49(5) 1083-1085. 

Cuthbertson DP, Tilstone WJ. 1968b. The effect of environmental temperature on healing of bone lesions in the rat. II. The effect of bone injury on mineral metabolism at 20° C and 30° C. Q J Exp Physiol 53 428-436. 

Bone disease and injun/. The most widely used isotope for bone studies is technetium-99m, which is incorporated into a variety of ions and molecules that direct the isotope to the tissue being investigated. Technetium compounds containing phosphate are preferentially adsorbed on the surface of bone. New bone formation (common to virtually all bone injuries) increases the incorporation of the technetium compound. As a result, an enhanced image appears at the site of the injury. Bone tumors behave in a similar fashion. 

B.F, Shahgaldi - Coral graft restoration of osteochondral defects, Biomaterials, 19, 205-213 (1998). J. Kotz, J, Bieniek and A, Bieniek, Application of porous bioceramics in experimental therapy in bone injuries. I Morphological and histological studies in the control animals, Arch. Immunol. Then Experim., 36, 89-96 (1988),... 

Nowadays, autografts, allografts, and xenografts are used for the restoration of bone injuries. Although the use of these grafts has presented satisfactory results under certain conditions, there are some restrictions associated with donor site scarcity, rejection, diseases transfer, and elevated harvesting costs. Due to the numerous drawbacks these grafts present, research has focused on the development of alternative synthetic materials. 

The initial tissue response when a biomaterial is implanted in the body is dependent on release of specific growth factors. It has been indicated by Frost [1] that the inevitable bone injury resulting from surgery and the presence of an implant will release various types of growth factors that will sensitize cells and promote cellular mitosis. This is a general healing response that will result in growth of all sorts of local connective tissues, bone as well as various types of soft tissue. 

Woo SL-Y, Maynard J, Butler D et al. Ligament, Tendon, and Joint Capsule Insertions to Bone. Injury and Repair of the Musculoskeletal Soft Tissues. Park Ridge, Illinois AAOS 1987 133-166. 

When imaging any long bone injury, it is imperative to include both the joint above and the joint below. Whilst Galeazzi lesions are rare in children, Monteggia lesions are not uncommon. It should also be stressed that the joint must be imaged in two planes. The elbow may look normal on the AP view but dislocation of the radial head is readily appreciated on the lateral projection. A straight line drawn up the shaft of the radius should intersect the capitellum in both AP and lateral views, irrespective of the degree of flexion of the joint (Fig. 18.13). 

Bone Injuries. The earliest experimental observation on the importance of vitamin C in the healing of bone was that of Shinya in 1922. He concluded that bones from scorbutic guinea pigs cannot be transplanted into normal animals. He attempted also to transplant sound bones into scorbutic animals, but his animals died of scurvy before results could be obtained. 

Fig. 51. Degenerated muscle fibers of the leg in a guinea pig suffering from partial vitamin C deficiency. Empty sarcolemmal envelopes can be seen containing wandering cells (near site of bone injury).

Fig. 54. An artery in a vitamin C-deficient guinea pig near the site of a bone injury. Note vaccuolation of endothelium.

The development of biomimetic and bioinspired multifunctional composite materials will have a significant influence on the development of novel, alternative methods and approaches for treatment of bone injuries and for surgical techniques in bone diseases, and could improve the effectiveness of the treatment of some diseases. In addition to these potential clinical applications, such engineered biomaterials can contribute to fundamental science, including better understanding of the interactions of materials with living cell systems. 

Injuries to the human lower extremities are mostly due to the collision of a vehicle and pedestrian, which results in fractures of long bones, injuries to the knee and ankle. This is because of the impact applied by the vehicle and high acceleration created in the lower extremities. Different injury mechanisms can be seen in long bones, which bending and torsional moments have been considered as major affecting factors [1]. 

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