The author has performed this excision frequently for disease; when the whole cartilages are removed and the wound is freely drained, an admirable result is obtained.

In cases of compound dislocation of the head of the metatarsal bone, it will occasionally be found necessary to excise it either by the original, or a slightly enlarged wound.

The author lately excised one-half of shaft of metatarsal and the corresponding half of proximal phalanx of great toe for exostosis, with antiseptic precautions. The result was a useful toe with a mobile joint.

Excision of Metatarsal Bone of Great Toe.—For this operation a quadrilateral flap has been recommended, but this is quite unnecessary. A single straight incision along the inner border of the foot, extending the whole length of the bone, renders it very easy to remove the whole bone from joint to joint. This is an operation, however, which is rarely needed, and which would leave a very useless flail of a toe. The operation, which is at once more commonly required, and also gives promise of a more satisfactory result, is the one performed for cario-necrosis of the shaft only, and in the following manner:—

A straight incision through all the tissues, including the periosteum, right down to the bone; then with nail or handle of the knife to separate the periosteum from the bone; then with a pair of bone-pliers or a fine saw to divide the shaft from both its extremities and remove it entire.[79]


CHAPTER IV.

OPERATIONS ON CRANIUM AND SCALP.

Trephining and Trepanning are the names given to operations for the removal of portions of the cranium by circular saws which play on a centre pivot. When the motion is given to the saw simply by rotation of the hand of the operator, as is common in this country, it is called trephining; when (as used to be the case in this country, and still is on the Continent) the motion is given by an instrument like a carpenter's brace, the operation is called trepanning.