The radial sagittal bands are incised to expose the MCP joints, and synovial tissues are sharply excised from the joints (see Fig. 35-3, sagittal band incision marked by dotted line).

The collateral ligaments are divided at the metacarpal neck, and heads of the metacarpals are resected at the proximal origin of the collateral ligament using an oscillating saw (Fig. 35-4). After metacarpal head resections, the fingers can be brought into alignment. Resection of the heads should decrease the tightness of the ulnar intrinsic tendons that contribute to ulnar deviation of the fingers. Therefore, ulnar lateral band release is usually not necessary, if sufficient resection of the head of the metacarpal is performed.

An awl is used to perforate the medullary cavities of the metacarpals and proximal phalanges (Fig. 35-5). Typically, the medullary cavities of the metacarpals are devoid of bone and are easily broached.

Sequential-sized broaches are used to enlarge the medullary cavity. The largest implants that will fit into the medullary cavity are inserted. Unlike the awl, which should be inserted in a twisting motion to enlarge the medullary cavity, the broach is rectangular in shape and should be inserted straight, without twisting, to make a square trough to accommodate the shape of the silicone implant ends (Fig. 35-6).

Two drill holes are made with a 0.035-inch Kirschner wire (K-wire) on the radial metacarpal, and 3-0 braided permanent sutures are placed through these drill holes for imbricating the radial collateral ligaments. These sutures are placed before insertion of the implants (Fig. 35-7A and B).

The implants are inserted (Fig. 35-8), and the radially placed 3-0 braided sutures are used to reattach the radial collateral ligament and bring the fingers into slight radial deviation (Fig. 35-9A to E). The ulnar lateral bands can be released, if they are still tight and cause the fingers to deviate ulnarly. However, as stated previously, ulnar band release is usually not necessary.

If the extensor tendons cannot be centralized easily because of tightness of the ulnar sagittal bands, these must be released as well. The extensor tendons are then centralized by imbricating the radial sagittal bands with 3-0 braided horizontal mattress sutures (Fig. 35-10A to D).

The tourniquet is released, and all bleeding points are cauterized. A drain is typically not necessary. The wound is then closed with interrupted absorbable dermal sutures, and the skin is closed with 4-0 horizontal mattress nylon sutures (Fig. 35-11). The hand is immobilized in a volar resting short-arm splint.