Ankle Arthritis: Fusion With a Bone Nail

Ankle Arthritis: Fusion With a Bone Nail

This cadaveric video will demonstrate a hindfoot ankle fusion using a bone nail to treat ankle arthritis. The important bones that help move the ankle include the tibia, fibula, talus, and calcaneus, or heel bone. Ankle arthritis often impacts the joint between the tibia and talus, called the tibiotalar joint, and can also impact the joint between the talus and calcaneus, called the subtalar joint. This video will demonstrate the use of a bone nail, which is a surgical implant used to compress the tibiotalar and subtalar joints together with the goal of fusing or minimizing movement between these joints to ultimately relieve pain.

Here is a right foot with the outside of the ankle facing the camera. The surgeon will make an incision on the outside of the ankle. Following the incision, the fibula, the long bone on the outside of the ankle, is visible. Before the bone nail and screws can be placed, a portion of the end of the fibula must be removed to prepare the necessary joints for the surgery, and later compress them for the fusion. After this is done, the surgeon accesses the tibiotalar and subtalar joints. The next step is removing the cartilage, the protective tissue on the ends of the bones that make up these joints. This allows healthy bleeding bone to be exposed so the 2 ends of the joint can heal together. After the cartilage is removed, the surgeon inserts bone graft using a syringe, which also encourages these joints to fuse or heal together over time.

Next, the surgeon will place 2 additional temporary wires through the tibia, talus, and calcaneus to set the placement for the eventual fusion. Here is an x-ray showing the temporary wires in the bones. Once the position is set, the surgeon will make a small incision on the bottom of the foot, just beneath the calcaneus, where the nail will be inserted. A pin will be placed in the trajectory of the eventual nail. Here is another x-ray showing the trajectory. The surgeon will then place a soft-tissue protector and metal guide in the incision. Additional temporary wires are inserted to hold this in place. The middle portion of the guide is removed, and then a reamer is used to make a hole in the bone. During reaming, bone from the remmers flutes is collected to be used as additional bone graft. This will be inserted in the joint spaces to further encourage the bones to heal or fuse together. An x-ray shows the reamer making a hole all the way to the tibia. Once the initial reamer has made the hole, additional reamers will be passed through this path to make the hole the appropriate size for the nail. Here is the bone nail that will be placed into the foot.

Attached to the nail is a thin metal cable that will later be used to add additional compression to the ankle. The attached black instrument is a guide that will be on the outside of the ankle during placement. The guide has holes that correspond to holes in the nail for eventual screw placement. The surgeon then mallets the nail into place through the bottom of the foot. Here is an x-ray showing the nail in the bones. Next, the surgeon will begin placing screws through the guide and nail, starting with a screw in the calcaneus. The first step is making a hole for the screw with a drill. The hole will then be measured and then a screw will be placed. This process will be repeated for a screw in the top of the nail. The nail will then be compressed using the metal cable. The compression handle will be turned from the outside of the foot. The ankle joint is shown compressing together during this process. Another screw will then be placed in the heel bone to lock the compression in place. Two additional screws will be placed in the nail, 1 in the talus and another at the top of the nail. The guide and tensioner will be removed. During removal, the compression cable is seen as it is pulled from the nail. The surgery is now complete and the incisions will be closed.