Among the many bones of the foot, the fifth metatarsal, a long bone on the outer edge, holds distinct importance in its anatomical placement and functional contributions. This article explores the precise location of the fifth metatarsal, its significance for overall foot mechanics, and common conditions that can affect it.
Finding the 5th Metatarsal on Your Foot
The fifth metatarsal is one of the five long bones in the midfoot, positioned between the ankle bones (tarsals) and the toe bones (phalanges). It is the outermost of these bones, running along the lateral, or outside, edge of the foot and leading directly to the little toe. You can locate this bone by starting at the base of your little toe and gently tracing backward along the outside edge towards your ankle. As you move your fingers along this path, you will likely feel a distinct, rounded prominence or bump near the base of the bone, closer to the ankle. This area, known as the tuberosity or styloid process, is where the fifth metatarsal connects with the cuboid bone, one of the tarsal bones in the midfoot.
How the 5th Metatarsal Supports Your Foot
The fifth metatarsal plays a role in the biomechanics of the foot, particularly in weight-bearing activities. It helps distribute pressure across the foot during walking, running, and jumping, absorbing forces that would otherwise concentrate in other areas. This bone contributes to the foot’s lateral column, providing stability and assisting in maintaining the foot’s arched structure.
The fifth metatarsal also serves as an attachment point for several muscles and tendons, including the peroneus brevis and peroneus tertius muscles. These muscles are important for movements such as turning the foot outward (eversion) and stabilizing the ankle. Their connection to the fifth metatarsal highlights its role in dynamic foot functions and propulsion during movement.
Common Injuries and Conditions
Given its position on the outer edge of the foot and its role in weight-bearing, the fifth metatarsal is susceptible to several specific injuries and conditions.
Jones Fracture
A Jones fracture is a break in a specific area of the fifth metatarsal, located slightly further from the ankle than the very base, in a region referred to as Zone 2. This type of fracture is caused by sudden impact, repetitive stress, or a forceful twisting motion of the foot. Healing can be slower for Jones fractures because this particular area of the bone has a more limited blood supply, which can hinder the natural repair process. Symptoms include sharp pain on the outside of the foot, swelling, tenderness, bruising, and difficulty putting weight on the affected foot.
Avulsion Fracture
An avulsion fracture of the fifth metatarsal occurs when a small piece of bone is pulled away from the main part of the bone by a strong tendon or ligament. This injury happens at the very base of the fifth metatarsal, closer to the ankle (Zone 1), and is associated with an ankle sprain or a twisting injury where the foot rolls inward. The peroneus brevis tendon, which attaches to this part of the bone, can exert enough force to cause this type of fracture. Signs include immediate pain, swelling, tenderness, and bruising along the outside of the foot.
Stress Fractures
Stress fractures are tiny cracks that develop in a bone over time due to repetitive forces or overuse, rather than a single traumatic event. In the fifth metatarsal, these can result from activities like long-distance running, prolonged standing, or sudden increases in physical activity. The pain from a stress fracture develops gradually, worsening with activity and improving with rest. Localized tenderness, swelling, and sometimes bruising on the outside of the foot are symptoms.
Bunionette (Tailor’s Bunion)
A bunionette, also known as a tailor’s bunion, is a bony prominence that forms on the outside of the foot, specifically at the head of the fifth metatarsal where it connects to the little toe. This condition can cause pain and discomfort, aggravated by wearing shoes that are too narrow in the toe box, which places constant pressure on the area. Symptoms include a visible bony lump, redness, swelling, and tenderness at the base of the little toe. The condition can be influenced by inherited foot structure.
For any of these conditions, persistent pain, swelling, or difficulty walking warrants medical attention. A healthcare professional can accurately diagnose the issue and recommend appropriate management strategies.