Talar Neck Fracture
Edited by Lance Silverman, MD
Talar neck fractures are very serious injuries. They occur following a major force that drives the foot up against the ankle. The ankle and foot will be swollen, painful, and possibly deformed. The nature of the fracture will typically need to be evaluated by performing x-rays and a CT scan. Most talar neck fractures are displaced and require surgery to reposition the bones back to their original position. Recovery requires a prolonged period (6-12 weeks) of non-weight bearing. Complications of the injury are unfortunately common and may include ankle arthritis due to loss of blood supply to the talus, subtalar arthritis, and/or malalignment of the foot.
Talar neck fractures in high energy accidents (ex. motor vehicle accidents) when a significant force is applied to the sole of the foot, forcing the foot to flex upwards (dorsiflex) and thereby driving the talar neck up against the front of the ankle joint.
In some instances, the force can be great enough to dislocate the talar body (the back part of the talus after the fracture) out of the ankle joint posterior (behind the ankle joint). It is also possible that the fractured bone may actually break through the skin at the time of the injury, creating an open fracture. Symptoms of a talar neck fracture include marked pain, swelling, and the inability to bear any significant weight.
Patients will have swelling, localized discomfort around the ankle joint, and may or may not have a nerve injury. The foot may appear deformed in an angulated or twisted manner.
A talar neck fracture can be diagnosed via x-rays of the foot. The fracture will be identified extending through the talar neck region. Occasionally, the fracture is undisplaced and can be difficult to read on plain x-rays. To more easily understand the fracture pattern, and particularly if surgery is being planned, a CT scan will be ordered.
It is very rare for a talar neck fracture to be truly non-displaced. However, if it is as demonstrated on the CT scan it may be treated non-surgically with non-weight-bearing and immobilization for 6-8 weeks until healing of the fracture is documented.
The treatment of a displaced talar neck fractures is operative (talar neck ORIF) unless there is a contraindication to surgery. The goal of surgery is to return the talus to its original position prior to the fracture. Although this procedure may be challenging, it is essential to get an anatomical reduction in order to avoid malalignment of the foot. Often, this requires two incisions – one on the inside and one on the outside of the ankle. The bones are then stabilized by screws and possibly a plate.
There are a variety of potential compilations that may occur following surgery to repair a talar neck fracture. Most of these complications are related to the original injury itself, and not the actual surgery. They include:
- Avascular Necrosis (Osteonecrosis) of the talar body. The nature of the injury routinely causes a variable loss of the blood supply to the back part of the talus – the part that forms the lower part of the ankle called the talar body. Your Orthopedic Surgeon should obtain x-rays of the ankle at 8 weeks from injury to identify the presence of a Hawkin’s Sign. This sign indicates loss of blood supply. This may permit the bone of the talus to collapse resulting in arthritis of the ankle joint.
- Subtalar Arthritis. The injury can also lead to arthritis in the joint below the talar body (the subtalar joint).
- Malalignment of the foot. The position of the talar neck dictates how the rest of the foot is aligned. If the bone cannot be restored to its original position due to bone loss or technical challenges, then the foot may be malpositioned (ex. curved inwards).
There are the usual variety of potential complications which may occur following surgery to fix a talar neck fracture. These include:
Edited on May 7, 2018
Previously Edited by Jean Brilhault, MD, PhD