Can Custom Bone Pegs Facilitate Effective Treatment Of Nonunions?
- Volume 20 - Issue 5 - May 2007
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At the beginning of the case, I start soaking the graft per protocol to optimize OR time. If the alignment is good, I draw alignment lines at the failed fusion site in order to prevent loss of correction. After pulling the original hardware, one should measure hardware for width and length. Revise the site and place temporary fixation. Remove the graft from the pre-soak and place it on the Mayo stand on top of OR towels. One would do this to reduce the vibrations from the sagittal saw during the fabrication. This helps keep the graft on the stand. Immobilize the graft with a bone clamp.
The surgeon makes the first cut with a sagittal saw through all three cortical walls from side to side at slightly less than the screw width. It is best to hold the resulting graft with a Kocker clamp. Cut the graft to form the short leg and long legs of the “L,” sculpting the cancellous portion of the peg at a width slightly less than the screw and tapering it at the tip. At this point, the other portion can be a second peg or one can utilize it as a backup.
The surgeon should then curette the hardware deficit prior to applying the peg. Hold the peg longitudinally with a Kelly clamp and cautiously advance it to three-quarters of the deficit. At this time, it is usually necessary to advance the peg with a light mallet and tamp. Stabilizing the peg with a stat decreases graft fatiguing when using a mallet. The peg’s cortical head should match the patient’s cortical wall at final seating. Place final fixation and reevaluate the pegs for proper depth.
A Closer Look At Pertinent Case Studies
One 54-year-old female had a closing base wedge bunionectomy. I was consulted after several months of standard delayed union care without response. The patient underwent a revision as described above. I removed the patient’s previous hardware (screw) and replaced it with plate fixation. I applied the peg as discussed above. On plain films, the cortical portion is clearly visible and a point of secondary fixation. The patient underwent an uneventful recovery with fusion within a six-week time period.
A 53-year-old male had a Lapidus fusion for gouty joint destruction. The patient had a gouty attack several weeks after surgery and the fusion was destroyed. We removed the screw fixation and placed two pegs. We utilized Nitinol staples as the primary fixation. The patient underwent an uneventful recovery with good signs of fusion and was pain free in seven weeks.
The Glazer Bone Peg technique can act as a lattice for new bone through the cancellous bone. The stability of the cortical wall on one border of the peg adds a level of rigidity without interfering with the easily replaced cancellous tract of the peg.
The peg should never be the only fixation. Using a plate or staples will help avoid encountering a peg during fixation. If one places a compression screw, one should do it in non-perpendicular planes to the peg. Perpendicular placement of the screw to the peg will crack the longitudinal portion of the peg. Use caution with long fixation deficits. The longer the deficit, there is an increased likelihood of peg fatigue during the tamping process. In regard to OR time efficiency, I recommend doing a first time application with an assistant. The assistant can prepare the peg site and apply temporary fixation as the lead surgeon prepares the peg.
One would follow a similar postoperative course as a surgeon would utilize with any other type of revisional nonunion case.
Dr. Glazer is an Associate Professor of Anatomy at Santa Ana College in Santa Ana, Calif. He is a Fellow of the Academy of Ambulatory Foot and Ankle Surgeons, and an Associate of the American College of Foot and Ankle Surgeons. Dr. Glazer is in private practice at Aloha Foot and Ankle Associates in Orange County, Calif.
Dr. Burks is a Fellow of the American College of Foot and Ankle Surgeons, and is board certified in foot and ankle surgery. Dr. Burks practices in Little Rock, Ark.
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