The model of a right femoral neck is shown. A crack formed in the neck joining the leg and the ball. The crack was caused by in impact directed upward from the bottom of the graphic.
The model of a right femoral neck is shown. A crack formed in the neck joining the leg and the ball. The crack was caused by in impact directed upward from the bottom of the graphic. |
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The screws a both 96 mm long. The one with the washer was removed after one year. The head of the other screw was stripped and could not be removed at the time of the operation. The author decided to apply TRIZ to generate more options than offered by the doctor. Leaving the screw in is not an acceptable solution. |
The stainless steel screw 96 mm long has a 16 mm thread.
The thread is self cutting in either direction. The stank is
4.5 mm.
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The threads are designed to cut the bone going or out. Note the 2 mm hole which was used by a guide wire when putting in the screw. |
The diameter of the head is 7 mm with a hexagonal hole 4.5 mm across the faces. Note the 2.1 mm hole. |
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Let's formulate the problem using TRIZ .
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