The use of arthrodesis for the correction of deformities is a cornerstone of podiatric surgery. From the proximal interphalangeal joint (PIPJ) for the correction of a digital contracture to a pantalar arthrodesis for the unstable Charcot foot and ankle, all podiatric surgeons need to be well versed in the principles for the fusion of joints. The modern general principles behind performing an arthrodesis were originally described by Glissan for the ankle arthrodesis. Since then, several organizations have added to the core principles in an attempt to provide a more predicable fusion.

In 1949, Glissan published his procedure for the performance of ankle arthrodesis, which has been notorious for delayed and nonunion of the fusion surfaces. He postulated that strict adherence to four basic principles would lead to a higher fusion rate (Table 55.1). First, the surgeon must completely remove all cartilage, fibrous tissue, and any other material that would prevent the close approximation of the raw bone surfaces that will comprise the fusion mass. Second, the surgeon must provide an accurate and close-fitting construct for fusion. Third, optimal position of the joint to be fused must be ensured. Finally, the surgeon must maintain the bone apposition in an undisturbed fashion until the fusion is complete (1). These principles revolutionized the steps that were undertaken to perform ankle arthrodesis and have been adopted, modified, and expanded by the AO for use in fracture repair.

In 1958, the AO was founded by world-renowned trauma surgeons in Switzerland who were unhappy with the lack of standardization in the treatment of orthopaedic injuries. Through their pioneering research into the basic science of bone healing, they modified Glissan’s principles for use in fracture healing/repair (Table 55.2). The AO principles include preserving the blood supply to the fracture or fusion, obtaining anatomic reduction, providing stable fixation, and beginning early, active range of motion of the involved body part (2). These principles have been integrated into common surgical practice and greatly enhance surgical visualization and stability in arthrodesis.

The integration of the above-mentioned principles into common surgical practice begin with proper surgical planning. The surgeon’s thorough knowledge of the indications for the procedure to be performed, the surgical anatomy, proper patient positioning, and proper anesthesia is of paramount importance. Additionally, the proper implants (screws, plates, wires, etc.) and instrumentation to insert the implants should be planned before surgery.

Proper incision placement is of the utmost importance when performing any surgical procedure. If an incision is improperly planned, inadequate visualization, excessive retraction on skin and soft tissue, and violation of vital anatomic structures will result. Additionally, improper incision placement may preclude the use of the most stable form of fixation for the desired procedure and may impede proper positioning. When planning the surgical incision, the desired joint exposure for resection and the proper exposure to insert fixation should be taken into consideration (Fig. 55.1).

Once the incision is planned, strict adherence to proper surgical technique is vital. This includes the use of anatomic dissection (tissue plane dissection) (Fig. 55.2). This is explained in further detail in the sections on specific surgical procedures. One point of emphasis will be in the periosteal dissection.

The periosteum provides approximately 80% of the blood supply to the bone (3). Because of its importance in the healing of the fusion site, it should be treated delicately. The preferred method to periosteal dissection involves making a linear incision in the periosteum to provide the exposure needed to perform the arthrodesis. Following incision, a Freer elevator is utilized to begin the subperiosteal dissection in a blunt manner over the diaphyseal area of the bone. This provides a known target layer on the proximal and distal aspect of the joint surface to be fused. In the periarticular area, the periosteum is continuous with the joint capsule and is firmly attached to the bone by Sharpey fibers. These fibers must be sectioned sharply in the same plane as the subperiosteal dissection (Fig. 55.3). However, care must be taken not to shred or lacerate the periosteum and capsule. By maintaining the periosteum as a single layer, the disruption of the periosteal blood supply is minimized.

After proper incision placement and utilization of anatomic dissection technique, the proposed joint for arthrodesis should be visualized within the surgical wound. The next vital step to successfully prepare a joint for arthrodesis is joint exposure. Without proper exposure, the surgeon will not be able to adequately resect the joint for arthrodesis. The two most efficient ways to gain exposure to a joint is either through joint disarticulation or joint distraction. The best way to gain exposure to a metatarsal phalangeal joint or an interphalangeal joint is through disarticulation (Fig. 55.4), whereas exposure to an intertarsal or ankle joint is most amenable to joint distraction.

It may be difficult to delineate or gain access to a joint secondary to severe degenerative changes. In these instances, a Sayer, Key, or Freer elevator may be useful to pry the joint apart (Fig. 55.5A). To maintain or obtain joint distraction, many surgical instruments are available. These instruments include lamina spreader, AO “mini distractor,” femoral distractor, tarsal distractor, and Weinraub distractor (Fig. 55.5B and C). After full visualization of the joint has been obtained, the joint is now ready for resection. Care should be taken to place the distractor


in a location in which it may provide optimal distraction but remain distant from the surgeon’s field.