Key Insights On Performing A Revisional Positional First MPJ Arthrodesis
The positioning of a first MTP arthrodesis is the most important step in this procedure. Most surgeons agree that the hallux should be parallel with the second digit, barring any digital deformity, and rest just off the weightbearing surface with the toenail facing superior in neutral. Depending on the patient’s anatomy, this position can be challenging, especially if it is a revision case. Some surgeons will use cup and cone reamers to fashion ball and socket surfaces. However, there must be no significant additional correction necessary if the surgeon wishes to implement this technique. When one must remove significant bone to achieve the desired position, partial or complete gapping can occur.
Corticocancellous allografts are a historic solution to bridging bony gaps. The properties of these are not optimal for bony fusion across such a cavernous gap. Reasons for allograft failure include resorption of the graft, thermal necrosis from fashioning, lengthy storage times, rejection, trabeculation issues over large areas, the freeze-dried/frozen nature of the graft, and cost.1,5-10
When it comes to cases like the one above, autogenous bone graft offers the surgeon and the patient the best predictable resolution. The locked plating and axial screw provide the stability needed for primary bone healing. Additionally, this technique allows one to fashion the graft in the desired position with optimal biomechanical accuracy and precision.
The four main principles of positional arthrodesis are as follows:
1. Adequate removal of the subchondral plate/fibrous tissue or bone to bleeding bone
2. Manipulation of bone segments into optimal anatomic functional position
3. Use of fully threaded positional screws and plates
4. Aggressive backfilling of gaps with the needed autogenous graft
Dr. DiDomenico is affiliated with the Heritage Valley Residency Program in Beaver, Pa. He is the Section Chief of Podiatry at St. Elizabeth’s Hospital in Youngstown, Ohio. He is the Director of the Reconstructive Rearfoot and Ankle Surgical Fellowship within the Ankle and Foot Care Centers in Ohio, and the Kent State University College of Podiatric Medicine. Dr. DiDomenico is a Fellow of the American College of Foot and Ankle Surgeons.
Dr. Thomas is a second-year resident at Heritage Valley Hospital in Beaver, Pa.