A Lisfranc sprain is a rare condition that's often misdiagnosed. When accompanied by a fracture, this joint injury accounts for less than 1% of all fractures per year. It's characterized by pain in the middle of the foot, abnormal swelling, and the inability to put weight on the injured foot.
What Is a Lisfranc Sprain?
The Lisfranc joint — or midfoot joint — is named after Jacques Lisfranc de St. Martin. He was a French surgeon who also served in Napoleon's army in the 1800s.
This joint is located at the arched area of your foot, also known as the midfoot. Here, there are a small set of bones, including the metatarsals, that extend to your toes. The smaller bones of the arch are called the cuneiforms and cuboid bones.
There are tight ligaments and other connective tissues that hold these bones together. This is important for stabilizing the foot, and transferring force from your calves to your feet.
With a Lisfranc sprain, these ligaments are sprained or torn. The bones of the midfoot may also be dislocated or fractured. Cartilage and other soft tissues can be affected, as well. The severity of a Lisfranc joint injury can range from simple to complex.
What Causes a Lisfranc Sprain?
Trauma to the foot can cause a Lisfranc joint sprain or fracture, especially if you stumble over the top of your foot as it points downward. Soccer and football players are at greatest risk for this type of injury.
You can injure the Lisfranc joint with just a twist and a fall, but high-impact injuries are often more severe and may include numerous dislocations and fractures.
A Lisfranc joint fracture may lead to chronic disability.
What Are Lisfranc Sprain Symptoms?
Lisfranc sprain symptoms include:
- Bruising around the foot (typically worse on the bottom part of the foot)
- Swollen foot
- Painful foot
- Pain that worsens with walking, standing, or weight-bearing
If you have a Lisfranc joint injury, you may need crutches to get around.
How is a Lisfranc Joint Injury Diagnosed?
First, your doctor will examine your foot and look for any swelling, bruising, and deformities. They'll ask you about the location and severity of your pain. They'll also likely test the blood circulation, strength, and range of motion of the foot.
You may get an X-ray that shows different views of the foot, including a weight-bearing view to determine whether it's a Lisfranc joint injury.
A doctor may also order an MRI to see if there are any injuries to the soft tissues — including cartilage, muscles, and tendons — or a CT scan to look at more specific images of the bones.
A Lisfranc sprain can often be misdiagnosed. It's important that a doctor differentiate a Lisfranc joint injury from a common ankle sprain, because the treatments are different.
What Is the Treatment for a Lisfranc Sprain?
If you've been diagnosed with a mild Lisfranc joint injury, you likely won't need surgery. Instead, your doctor may put on a short leg cast. To allow it to properly heal, you'll want to avoid putting weight on the foot for around 4 to 6 weeks. This should be followed up with a range of rehabilitation exercises to help build up strength in the foot.
If the injury is more severe, surgery may be necessary. Surgery should be done within the first 24 hours after the injury or after the swelling has gone down — usually 7 to 10 days later.
Internal fixation is one type of surgical method in which the bones are repositioned and stabilized with screws or plates. Since the Lisfranc joint is a mobile joint, this stabilization hardware will have to be removed, typically 3- 5 months after the surgery.
If the injury is severe, your doctor may want to do a bone fusion in which the damaged bones of the foot are fused together into one bone. The joints will not move after recovery, but people who get this kind of surgery will still be able to walk somewhat normally.
What Is Recovery Like After Lisfranc Joint Injury Treatment?
There are various physical therapy techniques to help you get back to walking without pain, depending on the type of stabilization treatment you had. Physical therapy will include gait retraining and a variety of flexibility and strengthening exercises.
With proper rest and rehab, most people will fully recover from a Lisfranc joint injury.