Oblique Fractures

An oblique fracture through the TGBA phase is shown in Plate 4. Here in addition to the gentle undulating fracture surface, which is similar to that of a... 

Fig. 7.1. a Pseudofractures of the epiphyseal ossification centres (arrows). The curved epiphyseal plates of the middle phalanges are superimposed on the secondary ossification centres at their bases producing an effect simulating fractures at the lateral margins, b Overlapping soft tissues of the fingers simulate oblique fractures in a child... 

Fig. 8.2a-e. The pattern of a fracture is determined by the forces applied to produce it. a Spiral fracture is the result of twisting/torsional forces, b Oblique fracture due to compressive forces, c Oblique fracture (with small transverse element) due to the bone being held fast and an uneven bending force applied distal to the fracture, d Transverse fracture due to bending force about a fulcrum, e-a Butterfly fragment due to compression and bending forces... 

Fig. 8.4. Oblique fracture of the tibial shaft with transverse component. Plastic deformation of the fibula...

Oblique fractures result from shear stresses, secondary to axial loading. Pure oblique fractures, however, are rare and, more commonly, there is a minor transverse element to the fracture (Fig. 8.4). Such injuries are due to uneven bending. The middle and distal or proximal end of the bone are fixed and the free end is moved. 

Fig. 8.8. Bowed fracture of the ulna with oblique fracture in the adjacent radius...

Fig. 8.11. Oblique fracture of the femur in a child with cerebral palsy stabilized with plate and screws. Medullary canal is too narrow for intramedullary implant. Fracture has united by primary healing. Note the lack of periosteal callus...

Fig. 8.12. Oblique fracture of the humerus 3 weeks post-injury. Extensive callus is visible and outlining the stripped periosteum...

As for femoral fractures, tibial shaft fractures are not specific for abuse, although in a non-weight-bear-ing infant without a history of significant trauma, abuse must be given serious consideration. In the ambulant infant, a steep, vertical, undisplaced spiral or oblique fracture is likely to be a toddler s fracture , an accident result from a twisting fall while the foot is fixed to the ground. 

There is no association between the morphological feature of a femoral fracture and the likelihood of abuse (Rex and Kay 2000). Although there is some disagreement in the published literature, transverse and oblique fractures seem to be the most common... 

Fig. 12.13. Oblique fracture of the right supra-pubic ramus and of the right iliac blade, indicating an LC Type 2 injury...

In a flexed elbow, a direct blow to the posterior aspect of the ulna, just anterior to the distal humerus, can cause a shear stress on the olecranon metaphysis, breaching the anterior cortex and with the radius and distal ulnar fragment displaced anteriorly by the pull of the brachialis and biceps. This may occur with the elbow either flexed or extended, leading to either a transverse or oblique fracture pattern (Table 18.2). 

C Extension Shear Oblique fracture through ulnar metaphysis with intact extensor mechanism... 

C6 and C7 are particularly susceptible to spinous process injuries. Traction injuries occur in flexion and compression injuries occur in extension. In extension the spinous processes impact against each other. Clay-shoveler s fracture is an oblique fracture of the spinous process of the C6-T3 vertebrae due to avulsion by supra-spinous ligament injury. The juvenile form is referred to as Schmitt s disease. The avulsion may not be visible on initial radiographs in children due to unossified centre here. However, follow-up radiographs will show callus formation and ossification along the supra spinous ligament. 

Type A3 fracture is characterized by a line that passes from the lateral femoral cortex below the greater trochanter to the proximal border of the lesser trochanter often there is also an undisplaced fracture separating the greater trochanter. A3.1 fracture is reverse intertrochanteric fractures (with an oblique fracture line) while A3.2 fracture is transverse (intertrochanteric). A3.3 fracture involves the detachment of the lesser trochanter, and is notoriously difficult to reduce and stabilize. 

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. 

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