Comminuted Fractures

My colleagues and I prefer to treat ACL avulsion fractures using a pullout suture technique under arthroscopy. We believe that the pullout suture technique can be applied in most cases, including those with comminuted fractures. Our surgical method is described below. 

Comminuted fractures include segmental fractures and those with butterfly fragments. Open or compound fractures occur when a wound extends from the skin surface to the fracture. 

Older children are more difficult to manage non-operatively. Internal fixation reliably maintains fracture reduction and allows early mobilisation, precluding the necessity for prolonged in-patient treatment. Close evaluation of the fracture will determine the appropriate implant to be utilised. Comminuted fractures lack both axial and rotational stability. By comparison, in the reduced position, a transverse fracture will display axial stability but may remain rotationally unstable. 

Fig. 25.8. Volume-rendered multi-detector row CT image of the ankle and hindfoot in a patient following a fall from a height. VR view shows a calcaneal comminuted fracture (arrows) with an involvement of the talo-calcaneal facet (arrowhead).The tendons are well depicted because they are surrounded hy fat...

Fig. 25.9a-c. Coronal (a) and oblique sagital (b) volume-rendered multi-detector row CT images and MIP reconstruction (c) in a polytraumatized patient with a severe crush trauma to the pelvis. VR (a,b) and MIP (c) reconstructions depict the extent of the comminuted fracture involving the ventral and dorsal pelvic ring, the iliac bone and the acetabulum. The urinary bladder (arrowheads) is partially filled with contrast medium, a urinary catheter is inserted. Images show a cranial displacement of the bladder indicating an injury of the neck of the bladder... 

Breaking injuries These injuries are generally associated with machines used for deforming various types of engineering materials. A break in a bone is referred to as a fracture. In turn, fracture is classified into categories such as incomplete fracture, simple fracture, compound fracture, transverse fracture, complete fracture, oblique fracture, and comminuted fracture. 

Schonert, K., 1972. Role of fracture physics in understanding comminution phenomena. Transactions of the Society of Mining Engineers, American Institute of Mining Engineers, 252, 21-26. 

It is possible that greater porosity in shale beds could be achieved by chemical comminution of the shale. For example, the treatment of western oil shales with acid solutions might result in comminution by inducing corrosive stress fracture of the carbonate rock. Chemical engineering research in this area, as well in the elucidation of oil-rock interactions, might provide insights for new strategies for oil shale production. 

The major purposes of comminution or size reduction operations can be summarized in four categories as shown in Table 2.2. Comminution is almost invariably performed in two or more stages. It starts with the crude mined or quarried product this is progressively taken to the desired final size by a step-by-step process. As the process of fracture is involved throughout this procedure, a brief discussion on the fracture of materials is appropriate at this point. 

Coldstream Process [11.7] (see the flow sheet Fig. 11.5). This process is a mechanical comminution and employs air blasts to accelerate particles against a target with sufficient energy to cause fracture (particle velocities near Mach 2). The air is cooled by expansion from the nozzles, protecting the scrap from oxidation. After screening or air classification, oversize material is recycled. 

Unlike fracturing, this approach should cause only moderate disruption of the coal matrix and might not lead to complete comminution, but this method could be envisioned as a prelude to coal grinding. Removal of material from structural boundaries would yield a more friable, "soft" coal structure. The leaching of fine mineral particles from the coal matrix results in a more porous structure and should also improve the coal s grindability. The prior removal of some mineral matter would also reduce the coal s abrasiveness. 

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