No abstract

A study was made of the mechanics of blood-bearing in a series of patients treated with a cast-brace for fracture of the distal femur. Knee hinges incorporating strain-gauges, a simple force-plate on the floor and a standardised weight-bearing test were used to record axial loads through the cast-brace itself and through the fracture during the phases of healing. The cast-brace carried loads of only 10 to 20 per cent of body weight and functioned mainly as an antibuckling hinged tube. Patterns of weight-bearing recovery showed that the fracture itself limited loads to safe levels. A measure of the recovery of strength at the fracture was determined and termed the "fracture load index". Graphs obtained in this way demonstrated four biomechanical phases of bony union which correlated well with the stages of clinical healing. The clinical application of these results have led to improvements in the design of braces and the use of a cylinder cast-brace for fractures of the distal half of the femoral shaft and of a new type of brace with a hinge at the hip attached to the thigh cast for fractures of the proximal shaft. A simple clinical test is described by which it is possible to monitor the healing of fractures in cast-braces.

Urinary diversion procedures in the dog have been described for both benign and malignant processes involving the bladder, urethra, or both. These procedures are performed rather infrequently, primarily because of the potential complications associated with urinary diversion into an intact gastrointestinal system. A case managed for five years following trigonal-colonic anastomosis for lymphocytic-plasmacytic urethritis is presented, along with a review of urinary diversion techniques. Postoperative management recommendations following urinary diversion are discussed.

No abstract

Various surgical procedures are described for common disorders on and about the ear. Photographs are presented to show how they are performed. Applicable surgical subtleties and precautions are discussed.