Midfoot Injuries (Lisfranc Injuries): Overview

Midfoot Injuries (Lisfranc Injuries): Overview

This video will provide an overview of Lisfranc injuries to the midfoot. We will discuss the anatomy, the causes of injury, the signs and symptoms, and how a diagnosis is made. The tarsometatarsal joint, or T M T joint, is a complex network of ligaments and bones in the midfoot. This area is often referred to as the Lisfranc joint. This joint is where the metatarsal bones in the foot communicate with the 3 cuneiform and cuboid bones.

The most crucial ligamentous connection at the TMT is the Lisfranc ligament. This ligament has 3 parts, including bands along the top, bottom, and in between the bones. This area is collectively referred to as the Lisfranc complex. Damage to the Lisfranc ligament will also damage the surrounding structures, including the soft tissue and often the bones. Ultimately, this will lead to a widening in this area.

Lisfranc injuries are uncommon and represent <1% of fractures. The overall incidence is 1 in 55,000 people per year and are 2-4x more common in men. There are 2 types of ways this area can be injured: either through direct, high-energy trauma or indirect, low-energy trauma. In a direct high-energy trauma, a force impacts the top of the foot overlying the TMT joint, causing a collapse of the natural arch of the midfoot. A crush injury is an example of this type of mechanism. A car accident is a common cause of high-impact injury to this joint.

An indirect, low-energy trauma often occurs when the front of the foot is planted and loaded suddenly with weight. This places the foot in a vulnerable position. The foot can shift backwards, known as the plantar position, or shift forward, also known as dorsal position. Indirect, low-energy trauma is the most common cause of injury and is commonly seen in sports such as American football or gymnastics. Missteps on curbs or stairs are another example of a low-energy, indirect cause.

Often, swelling and bruising are seen at the base of the foot. However, in a low-energy trauma, the foot may look normal. In high-energy trauma, severe skin injury, such as blistering, may be seen. Emergency treatment is required for Lisfranc injuries that have fractures that break through the skin. If a patient has loss of sensation or decreased blood supply to the foot, emergency intervention is needed.

Approximately 20% of Lisfranc injuries are misdiagnosed. Therefore, seeking treatment early and with the appropriate specialists is critical in obtaining the proper diagnosis. To begin making a diagnosis, a health care provider will examine the foot closely for pain on both the top and bottom of the joint. The provider will also move the second metatarsal up and down to evaluate for abnormal movement at the joint. The function of the nerves and vessels will be assessed, given their proximity to the injury site.

After examining the foot, multiple x-rays will be taken. The health care team will try to obtain these x-rays while the patient is standing to best see subtle changes in the alignment of the bones. Often, an x-ray of the other foot is taken to compare for subtle differences. A CT scan may be ordered to better evaluate the injury, especially if a fracture, or broken bone, is suspected. An MRI may also be considered to help make the diagnosis. Once a diagnosis has been made, the health care team will discuss the timing and type of treatment best for the patient.