Peroneal tendinopathy is a condition that affects the peroneal tendons, which run along the outside of the ankle and connect the lower leg muscles to the foot. These tendons help stabilize the ankle and support movements such as walking, running, and changing direction. When the tendons become irritated from overuse or repetitive stress, they can develop small injuries that lead to pain and swelling.

This condition is most commonly seen in athletes who run, jump, or play sports that involve frequent side-to-side movements, but it can also affect anyone who regularly places extra stress on the ankle. Risk factors include high arches, frequent ankle sprains, or spending long periods on uneven surfaces.

The most common symptom is pain along the outer side of the ankle. This pain may feel sharp during activity or present as a dull ache at rest. Swelling and tenderness are often present, and symptoms typically worsen with exercise or prolonged activity. Many people also describe a sense of weakness or instability, as if the ankle could “give way.” Walking on uneven ground or pushing off the foot can make the discomfort more noticeable.

In some cases, the pain may linger over time and become chronic if the tendons are continually stressed without proper recovery. Recognizing the signs of peroneal tendinopathy early is important so that patients can make changes to their activities and prevent further tendon irritation.

A lateral ankle sprain happens when one or more of the ligaments on the outside of the ankle are stretched or torn, usually from the foot rolling inward (inversion). This is the most common type of ankle sprain, especially in sports like basketball, soccer, and football, but it can also occur during everyday activities such as stepping into a hole or landing awkwardly from a jump.

The typical presentation is sudden pain on the outer ankle, sometimes accompanied by a “pop” at the time of injury. Pain may range from mild to intense and is often worse with weight-bearing or later in the day. Swelling and bruising are common, and rapid swelling suggests a more severe ligament tear. Bruising may shift downward into the foot over time. In rare cases, numbness, tingling, or a cold foot may indicate nerve or circulation problems that need urgent attention.

The ankle is stabilized by three main ligaments: the anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). The ATFL is the most frequently injured, with about 75% of sprains involving this ligament. Injuries can be graded as mild (Grade I), moderate (Grade II), or severe (Grade III, complete tear).

On exam, there is usually tenderness over the injured ligament, swelling, and limited motion—especially with inversion or upward bending (dorsiflexion). Special orthopedic tests may be used to check ligament stability once swelling decreases.

Because ankle sprains are so common and can recur, early recognition and proper care are important for long-term ankle health.