The Commonly Fractured 5th Metatarsal
The 5th metatarsal is the one of the most common bones fractured in the foot. Situated just below the 5th toe, the anatomy of this bone influences the type of fracture that develops. The metatarsal itself is comprised of a base, tuberosity, shaft, neck, and head. The tuberosity, which is the posterior-most aspect of the bone near the midfoot, is clinically evident as it protrudes laterally (some people complain that this rubs in their shoes). Tuberosity fractures, also known as avulsion fractures, can be displaced or non-displaced. The position of the fracture will determine the type of treatment. For non-displaced fractures, the treatment is conservative and focuses mainly on symptoms. This includes protected weightbearing in a hard-soled walking boot or a short-leg walking cast. Pain usually resolves after a few weeks, and healing of the fracture fragment itself on x-ray is evident after approximately 6-8 weeks post-injury. These types of fracture generally heal well with no long-term complications. Larger, displaced fragments are commonly treated surgically, which varies from percutaneous pinning (making a small cut in the skin and inserting a screw without having to expose the entire metatarsal) to open reduction with internal fixation (exposing the metatarsal and placing pins, plates, and / or screws across the fracture site).
Another common type of 5th metatarsal fracture is known as a Jones fracture. The location of this injury is slightly more anterior to the tuberosity (1 cm from the joint, closer to the toes than the tuberosity fracture). The Jones fracture takes a longer time to heal because of the poor blood supply at this particular location in the bone. Treatment can be either conservative or surgical, depending on the patient's age, health, and activity level. Conservative treatment involves 6-8 weeks of strict non-weightbearing cast immobilization, followed by a few additional weeks of weightbearing boot or cast immobilization. Surgical treatment, which is similar to that described for tuberosity fractures, is generally recommended for athletes and more active individuals and allows shorter periods of immobilization with faster healing times.
Common to both types of fracture are soft tissue attachments found at the base of the 5th metatarsal. A muscle tendon (peroneus brevis muscle) from the lateral leg compartment courses down into the foot and attaches at the base. The lateral band of the plantar aponeurosis (which can occasionally be the culprit of infamous heel pain known as "plantar fasciitis") also attaches here. These two soft tissue structures have the potential to pull at the fracture fragment, thus causing possible displacement and, unfortunately, complicated fracture healing. This is why it is extremely important to seek treatment with myself or one of our doctors immediately at Advanced Foot and Ankle Care if you suspect that you have sustained a 5th metatarsal fractures.