This past week a professional football player ended up with a fracture of his foot during a throwing session. The break was located between the base and the shaft of the 5th metatarsal bone, classified as a Jones fracture. You don’t have to be a professional athlete to sustain one of the most common fractures of the foot.
I received a call from a patient recently who rolled over on her foot while coming down the stairs at home. Almost immediately she developed swelling, bruising and pain. X rays of the foot showed a fracture of the base of her 5th metatarsal.
Fractures of the 5th metatarsal bone are one of the most common fractures in the foot. A majority of the literature focuses on fractures of the base of the 5th metatarsal. These fractures are caused by a twisting of the foot, with the front of the foot turning inward and the heel off the ground. This mechanism of injury commonly occurs when rolling off a step or a curb, in the case of professional athletes, a sudden change of direction, or the twisting of a dancer’s foot.
The Stewart Classification system outlines 5 types of 5th metatarsal base fractures based on their location:
Type I – Extra-articular transverse or oblique fracture between base of 5th metatarsal and diaphysis (Jones fracture).
Type II – Avulsion fracture of base of 5th metatarsal with intra-articular extension. May have one or two fracture lines.
Type III – Avulsion fracture of styloid process of 5th metatarsal. Fracture line usually makes a right angle to the long axis of the metatarsal base.
Type IV – Intra-articular comminuted fracture.
Type V – Usually occurs in children. Partial epiphyseal avulsion with or without fracture line. Can be classified as Salter-Harris I type fracture.
X rays of the foot are always the first line of imaging. A CT or MRI may be ordered if there is a concern for slow healing, no healing or a stress fracture.
Treatment is based on the location of the injury, if healing has already started to occur, and the social and medical history of the patient. The typical treatment course is initial strict non weight bearing in a walking boot followed by gradual weight bearing for a total of 6-8 weeks. Surgery is usually performed in high-performance athletes, patients who choose to proceed with surgery after discussion of conservative and surgical risks and benefits, and those whose fracture is out of alignment.
5th metatarsal base fractures have a tendency to heal slowly or not at all due to poor blood supply to the bone. Timely diagnosis, treatment or appropriate referral is critical to avoid potential complications.
Also important to note is that not all 5th metatarsal fractures occur at the base of the bone. Stress fractures, mid-shaft and head fractures are also common.
