A Closer Look At Fixation Options For The Charcot Foot
When Jean-Marie Charcot described the entity that bears his name in 1868, little did he know the controversies he would create. Charcot joint disease (or Charcot neuroarthropathy) has been one of the most misdiagnosed conditions in patients with diabetes mellitus. Patients with this entity have been misdiagnosed and consequently mistreated for osteomyelitis, cellulitis, tendonitis and gout.
Over the years, various controversial questions have been posed about the treatment of Charcot neuroarthropathy. These questions range from what type of diagnostic tests one should order to what type of surgical intervention is indicated for Charcot joint disease. The controversy continues to this day. In recent years, surgical reconstruction of the Charcot foot and ankle has become more aggressive. Less “lump and bump” surgery is advocated and more surgeons are performing primary fusion procedures. Fixation devices have run the gamut from simple staples to large diameter screws, intramedullary rods and complex external fixators.
Are these passing fancies or are these devices the saviors of the diabetic foot their proponents claim them to be? Unfortunately, there are few studies that will objectively answer these questions. This article may in fact raise more questions than it answers. Hopefully, it will provide some rationale for the use of fixation devices.
When Surgery Is Necessary
When clinicians diagnose Charcot neuroarthropathy early and treat it appropriately, the majority of patients do well with conservative treatment. They will be left with feet that are free of ulcerations and have minimal residual deformities. Employing protective shoes or braces can help prevent the severe consequences of the neglected or misdiagnosed Charcot joint.
Unfortunately, a large number of patients will present with foot deformities, instability or ulcerations as their initial symptoms. For those patients, one can consider a variety of surgical options, which range from simple exostectomies to exostectomies with rotational flaps or even free tissue transfers. In more severe deformities with significant instability, primary fusion may be the procedure of choice. The level of the deformity will dictate the level of fusion whether it is a midfoot, triple or ankle arthrodesis.
Today, the use of plates, screws and intramedullary nails has become standard practice in these complex fusions. They provide more solid fixation with improved outcomes. Cannulated screws facilitate relatively simple insertion.
In recent years, the use of external fixation has become more commonplace. These devices have undergone significant changes since their introduction into surgical practice in the late 1800s. Circular frames with skinny wires have replaced the unirail with Schanz pin systems for the most part. Additionally, these circular frames can either be static or dynamic depending on the goals of the surgeon.
Internal and external fixation play key roles in reconstructive surgery of the Charcot foot and ankle. Understanding the indications for these modalities will allow for more successful outcomes and fewer complications.
What Advantages Does Internal Fixation Offer?
Internal fixation is best suited for subluxed joints with minimal bony destruction. Good bone quality and substance are essential for screw purchase. It is also preferable to place screws where an intact soft tissue envelope exists. This implies that whenever possible, it is best to perform surgery when plantar ulcerations are healed. Also be aware that the presence of unresectable osteomyelitis is a contraindication when it comes to using internal fixation.