Microsurgery: Transplantation and Replantation by Harry J. Buncke, MD, et al.
  Table of Contents / Chapter 32:
Bony Fixation in Replantation
 
  Regardless of the fixator used or the anatomic site, the fixation device should be laid out and assembled before application to determine optimal pin placement and the subsequent location of the frame. Pins should be positioned to bypass important structures and placed with slow-speed drilling to reduce bone trauma and ensure solid pin placement. Careful avoidance of soft tissue and gliding structures is important. Intraoperative x-ray confirmation of adequate reduction should be used to confirm the clinical impression of position. The appliance should be rechecked for tightness and stability. Postoperative care includes frequent evaluation for clamp tightness and meticulous pin site care. Both the patient and the nursing staff should be encouraged to keep pin sites clean to allow drainage without bursa formation and to prevent deep infection.

EXTERNAL FIXATION IN HAND FRACTURES

There are a number of different appliances on the market for external fixation of the hand that vary only in their method of external pin control. All are based on the placement of threaded pins in both cortices of bone, which are then fixed externally in some holding appliance. A simple and low-cost technique is to use acrylic resin or polymethyl methacrylate as the holding device, though the result is not adjustable. The small Roger Anderson set is simple in application, but once it is in position, correction can be made in only one dimension. This limits its adaptability. The Hoffman mini-external fixator, however, has full three-dimensional conformability, including both distraction and compression of fracture fragments. This can be performed both intra- and postoperatively. The price paid for this improved fine control is a modest increase in the degree of complexity in application and hardware, requiring a moderate amount of practice with the device.

 

THE HOFFMAN MINI-EXTERNAL FIXATOR

The addition of this external mini-fixator to the arsenal of the reconstructive surgeon greatly adds to the flexibility in the approach to complex hand and wrist injuries. The tools required are a power drill, a 1.5-mm drill bit with drill guide, 2-mm threaded pins, and a matching socket wrench set. Frame components consist of 3-mm connecting rods, pin clamps, and linking pivots for interconnecting segments of the frame. Swivel components are also included for adjusting the three-dimensional position and rotation. Insulated braces are available in the larger sets. The pins are drilled into bone with bicortical purchase through small stab wounds after the bone is adequately cleared of soft tissue. Parallel pin placement is aided by a hand-held guide. Once drilled, pins are held in a bracket, which is later attached to adjustable swivel clamps and positioned to allow distraction or compression as needed. The clamps are threaded onto connecting rods, and the complex tightened into position as soon as fracture reduction and bony alignment have been completed.

OTHER FIXATION TECHNIQUES

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