Fifth metatarsal fractures are breaks in the fifth metatarsal bone, the bone that connects the little toe’s proximal phalanx — that is, the phalanx closest to the ankle — to the cuboid bone. This bone can be susceptible to breaks, particularly for very active people. There are three main types of metatarsal fractures: Jones fractures, avulsion fractures, and spiral or oblique fractures. Some of these fractures may also be acute, a sudden break, or chronic, a break that occurs as a result of repeated stress. The method chosen to treat these breaks depends on the type of the break and the person receiving the break.
A Jones fracture, one of the three main types of fifth metatarsal fractures, was named after Sir Robert Jones, the man who first described them. This type of fracture can be caused when stress is placed on the bone while the foot is flexed — the toes pointing to the ground while the heel is lifted. Avulsion fractures are caused when one of the ligaments in the foot pulls a fragment out of the bone. This fracture is often caused by the ankle rolling and may accompany a sprained ankle. The oblique fracture is caused by trauma or stress and can result in an unstable break.
There are acute and chronic designations for these fractures. An acute fracture occurs all at once from a single traumatic event. By contrast, chronic fractures, or stress fractures, occur as a result of repeated stress. In cases of chronic breaks, the repeated action can occur over weeks or months before the actual fracture is visible on an X-ray. Most fractures are accompanied by symptoms such as pain, swelling, and bruising. The symptoms of a stress fracture may start off relatively slight and increase as the injury progresses.
When speaking of fifth metatarsal fractures, doctors often separate the bone into three zones. The first zone is close to the proximal area of the bone, that is, the area nearest the ankle. Avulsion fractures usually occur there. The second zone is closer to the tip of the little toe than the first zone. The third zone is the closest zone to the little toe.
Treatment options for fifth metatarsal fractures can be either conservative or surgical, depending on the break and how quickly the patient wants to get back to activities. Oblique fractures in which there is no displacement and avulsion fractures are often treated by immobilizing the foot in structures like a boot or a surgical shoe. Jones fractures may have to be treated with a knee high cast. In either case, there is often a period where a patient should not put any weight on the bone. When surgery is called for, it usually entails the insertion of screws that hold the bone together.