Rigid Flatfoot Deformities: Flatfoot Reconstruction With a Triple Fusion Using Staples and Screws

Rigid Flatfoot Deformities: Flatfoot Reconstruction With a Triple Fusion Using Staples and Screws

This video will provide a demonstration of a triple fusion procedure for a rigid flatfoot deformity on a cadaveric specimen. This will be done with the use of staples and screws. A triple fusion involves 3 joints in the foot: the subtalar joint, the talonavicular joint, and the calcanealcuboid joint, or C C joint.

The surgeon will begin with the subtalar fusion and will make an incision to the outside of the foot, overlying the joint. Once the soft tissues are exposed, a retractor will hold open the surgical field. The surgeon identifies several important structures in this area: the peroneal tendons, the sural nerve, and the C F L, or calcaneofibular ligament. The surgeon will use an instrument to distract or pull the subtalar joint open to prepare the joint for fusion. This allows the surgeon optimal viewing of the joint.

The surgeon will use a tool to remove the thin, protective layer of cartilage from the bone ends. The cartilage must be removed for the joint to fuse. This is the joint after the cartilage has been removed. The first of 3 wires will be placed as a guide for incoming compression screws. The first wire is shown already placed across the joint. The surgeon is now placing a second wire. This x-ray shows the 2 wires across the joint. Multiple x-rays will be taken from different angles to confirm their placement.

A third wire will be placed in a new plane to provide further support. A depth gauge will be placed over the first wire to measure the length of the first screw. Then a specialized drill bit called a profile drill will be used to make the initial path in the bone for the incoming screw. The profile drill will be removed, and a drill bit will be used over the wire to create the full path for the screw. X-rays will continue to be used to verify the safe placement of the instruments.

The drill bit will be removed, and the initial wire will remain in place. A cannulated or hollow-bodied compression screw will be placed over the wire and placed across the joint first with a power drill, then completed with a hand driver. An x-ray will be done to check placement. The exact process will be completed for the next screw. Here, the 2 screws are shown. For the final wire, the process will be completed with a smaller size screw. The final x-ray shows all 3 screws in place.

Transitioning to the second fusion, the surgeon will make an incision to the top of the left foot, overlying the talonavicular joint. Here is the exposed joint. An instrument will open the joint so the cartilage again can be removed. Here is the joint with the cartilage removed in preparation for the fusion. Although not shown, bone graft may be used in this space to assist with healing. A wire will be placed across the joint temporarily to hold the desired position prior to placing hardware.

For this fusion, the surgeon will be using surgical bone staples instead of screws to hold the bones together. To prepare the bones for the staple, a drill guide will be used. Two holes will be drilled into the bone on either side of the joint. A pin will be used as a placeholder in 1 of the holes. The pin and guide will be removed as the staple is brought into the holes. The staple will be tapped into place with a mallet. The staple holder will be removed, and the staple will be tapped flush with the joint.

Two smaller staples will be placed in similar fashion on each side of the larger initial staple. Here you see an x-ray of the 3 staples compressing the talonavicular joint and the screws from the prior subtalar fusion. The final joint in the triple fusion, the calcanealcuboid joint, will now be fused with staples. An incision overlying this joint has already been made from the prior subtalar fusion. Two holes will be drilled into the bone on either side of the joint. A pin will be used as a placeholder in 1 of the holes.

The guide and pin will be removed, and the staple will be tamped into place. The staple holder is removed, and the staple is tapped flush with the joint. A second staple is placed below the first staple in the same fashion. Here is a final x-ray of the back of the foot showing the triple fusion to include the subtalar screws, the talonavicular staples, and the calcanealcuboid staples. The incisions will be closed. Dressings and a splint will be applied. The surgery is now complete.