Microsurgery: Transplantation and Replantation by Harry J. Buncke, MD, et al.
  Table of Contents / Chapter 1:
Great Toe Transplantation
  The vascular anatomy in the first web space of the hand can be plotted accurately with the Doppler probe. A good signal over the dorsal radial artery where the princeps pollicis plunges through the first web space is most helpful. On the foot, a strong Doppler signal that persists down the first intermetatarsal space to the first web space usually indicates a dominant superficial first metatarsal artery arising from the dorsalis pedis artery. If a cutaneous signal is not easily picked up in this area, the major arterial supply to the toe presumably comes from the deep plantar system. The Doppler signal correlates with the arteriogram and operative findings in over 90% of cases.12 In any event, the anatomic dissection involves exposing both the dorsal system, in the process of mobilizing the venous supply, and the plantar system, in the process of separating the blood supply from the great toe to that of the second toe in the distal portion of the first web space. The best and largest vessels of the two systems can then be selected. In some instances, they may be of equal size, and both the superficial and deep systems can be preserved. It is much safer and simpler to extend the plantar system with a reversed vein graft than to depend on an attenuated superficial first metatarsal artery to carry the transplant.

The next most important technical consideration is the planning of the incisions and skin flaps on both the hand and foot. An adequate first web space must be created or preserved if the transplant is going to restore useful grip and pinch to the hand. For this reason, the thumb is usually opened through a dorsal coronal incision, somewhat to the radial side of the midline of the thumb, so that tissue can be slid toward the ulnar side and into the first web space. A skin flap can then be carried proximally on the medial side of the toe transplant, if it is taken from the same side as the hand, to fill the defect on the hand. Closure on the foot is also facilitated by placing the skin flap on the medial aspect of the toe and metatarsal area. A narrow, long triangular flap should be brought well proximally along the course of the great saphenous vein draining the toe. The long proximal flap can also be used to cover the vascular pedicle and anastomoses in the hand. The subcutaneous fascia around the venous and arterial pedicles is carried as a cuff or flange of vascularized tissue that can support a skin graft and permit loose closure on the hand. The actual positioning and planning of these flaps should be worked out on a preliminary basis with clay or plaster models of the proposed transplant and recipient flaps. Closure of the donor defect on the foot becomes a serious problem if too much tissue is carried with the toe. Delayed healing and skin grafts over the residual metatarsal stump can create a wound problem of considerable magnitude. It is better to carry less tissue from the foot and make up deficiencies on the hand with split-thickness skin grafts, especially on the radial aspect. A marked shortage of tissue cover on the hand must be corrected with either preliminary or simultaneous cutaneous flap or muscle transplants.


The patient must be positioned on the table so that both the hand and foot dissections can be done simultaneously by two operating teams. Both dissections should be completed under tourniquet control with 4.5- to 6-power loupe magnification. At least two people are necessary in each field of dissection on the hand and the foot, preferably with a separate scrub nurse for each team. The ideal operating room should have four overhead lights, two for each area of dissection. If the operating microscope is on a stand, it can be kept out of the area until the microsurgical repairs are begun. If the microscope is fixed to a ceiling mount, one should position the operating table for the preliminary dissections so that the microscope mount does not obstruct the free movement of the operating teams and scrub nurses. This interference is often a problem and can be considered one of the major criticisms of overhead fixed mounts.

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