1. Extension at any angle with motion. 2. Extension at any angle with fixation. 3. Fixation at any angle.

4. Motion, complete or limited, constant or occasional.

5. Exposure of surface about the joint, admitting compression, elastic or otherwise, hot and cold applications, blisters, dressings, and easy inspection.

6. Motion, extension, and elastic tension by the addition of appropriate rubber cords.

This splint may be inserted into any form of brace attachment known. But when it is desired that the splint should remain upon the limb for any length of time, or, as in acute inflammation of joints, where it is used to reduce the contractile antagonism of the muscles, I prefer to use it in the form of a bracket, which is to be attached to the affected part by some immovable dressing, which will be sufficiently inflexible to prevent unequal pressure upon the soft parts.

The sector bracket consists of two terminal plates of thin copper, perforated upon the upper side, connected with each other by a sector bridge raised to any desired distance from the surface. This bridge consists of two overriding slotted steel strips, connected by three clamps which may be either thumbscrews or key-clamps. To this has been added a ratchet upon the upper bar for further increase of extension without alteration of angle.

With regard to the attachment of this bracket, I prefer my combination dressing of swans' down adhesive plaster and flour paste, to the plaster of Paris so much in vogue, because: 1. It

is much lighter. 2. It is more cleanly. 3. It adjusts itself as perfectly to the surface, and has no subsequent expansion or contraction in bulk-one of the chief demerits of plaster-ofParis. 4. Its adhesive properties.

For example. Suppose the knee to be the affected joint upon which the sector splint is to applied with this dressing. When dry, this upper dressing forms the segment of a hollow inflexible cone which has firmly grasped the muscular structures above the joint-the smaller end of the cone being nearer to the jointand thus any extensible force which pushes this segment farther apart from the other acts in direct antagonism to the inherent strength of the muscles-causing them to assume less bulk, without reducing their vitality in the least, or interfering with their capillary circulation, and since one segment is over the bulk of the thigh muscles and the other segment is unalterably fixed over their insertion just below the knee-joint, and for a little distance beyond the convexity of the calf-muscles (as some of the fibres of the thigh tendons are finally lost in the fascia of the leg), it will be seen, when extension is produced (by pushish up the upper strip of the sector and fastening the upper clamp, leaving the other two loose, thus allowing motion), that the reflex contractility of the muscles of the joint, and the weight are both transferred to the sector and its attachments, thus placing the joint in the very best possible condition for recovery by making it to all intents and purposes a dead joint.

It will be seen, then, that in order to successfully apply a system of local extension, whether to joints or fractures, the attachment below the joint must be fixed unalterably, and the extension force exerted in the axis of that part of the limb above the joint, and directed against the inherent contractile resistance of the muscular mass governing the joint until it is neutralized by the power of the entending rod. In this way, then, we get our two fixed points, and lift the entire weight of the body off the affected joint without affecting any other part of the limb except that immediately about the joint, which joint is rendered inert and relaxed, and yet a healthy degree of motion allowed to prevent ankylosis.

By the screw upon the upper bar, which I have since added (Fig. 5), increased extension is allowed without change of angle, which is an important quality if fixation is employed. In short, this splint in its various forms is the basis of a new and complete VOL. XXXII.-30

system of local extension, which is applicable to any joint and all conditions of joints, and will prove to be invaluable among the resources of surgical mechanics.

The forms of the sector splints vary according to the part affected. For muscular deformities of the spine it is of the shape shown (Fig. 6), and accomplishes more than any other form of

spinal dressing now in use. It bears the same relation to the plaster jacket that the sector knee-joint splint does, to confining that joint in an immobile cast of plaster allowed to set while heavy weights are attached to the limb to produce extension. You imprison extension in a fixed position, but you do not get motion or exposure of surface, or the opportunity of combating muscular inequality by appropriate rubber cords, which are necessities in

the most successful treatment of all forms of deformities due to or accompanied by muscular insufficiency. Nor can you change the amount of extension at will. Now all these things the sector back splint allows you to do at pleasure, and is, therefore, not only an agent for relief but for permanent cure. Your fixed point is the pelvis, and you lift the superincumbent weight off the affected portion of the spine and transfer it to the splint, and at the same time, by the use of appropriate elastic cords, you relieve all deformities due to muscular insufficiency as far as they can be relieved by mechanical means.

HIP-JOINT.

For affections of the hip-joint the splint is applied externally, and is also provided with a horizontal movement for rotation of the thigh when desired. (Fig. 7.)

rod attached to the thigh piece, I have devised in addition to the external sector (see Fig. 8). It must be noticed, however,

Fig. 8.

Perineal rod.

Showing perineal extension rod.

that this metallic perineal curve does not, like the perineal bands of the hip splints now in use, touch or impinge in any

Fig. 9.

Stillman's sector hip brace.