os peroneum

A Comprehensive Guide to Os Peroneum

A Comprehensive Guide to Os Peroneum


Os Peroneum is a small accessory bone located in the foot, specifically in the lateral aspect near the base of the fifth metatarsal bone. It is a sesamoid bone, which means it is embedded within a tendon. The os peroneum is commonly found in the peroneus longus tendon, but variations in its location can occur.

What is Os Peroneum?

The Os Peroneum is an extra bone that exists in the foot, commonly in the peroneus longus tendon. It is a small rounded bone, usually measuring about 10-15 mm in length. This accessory bone is not present in every individual, and its presence can vary.

Role and Function

The os peroneum serves as a fulcrum for the peroneus longus tendon, enhancing its mechanical advantage during plantar flexion and eversion of the foot. It helps to stabilize the tendon and prevent it from bowstringing, ensuring proper function and efficiency of the peroneus longus muscle.


Location and Structure

The os peroneum is usually located within the peroneus longus tendon, near the cuboid bone on the lateral aspect of the foot. It lies in a groove at the base of the fifth metatarsal bone. The bone may be embedded within the tendon or lie adjacent to it.


Although the os peroneum is commonly found in the peroneus longus tendon, variations in its location can occur. It may be absent in some individuals or present as multiple small bones. These variations can be seen in different locations within the tendon or even in adjacent structures.


Os Peroneum Fracture

An Os Peroneum fracture is a break or crack in the accessory bone. Fractures can occur due to direct trauma or excessive stress on the bone. Symptoms of an Os Peroneum fracture may include pain, swelling, and difficulty with foot movement. Treatment options range from conservative measures to surgical intervention, depending on the severity of the fracture.

Os Peroneum Syndrome

Os Peroneum Syndrome refers to the irritation and inflammation of the peroneus longus tendon and the surrounding structures. This condition can be caused by repetitive stress or trauma to the area. Symptoms may include pain, swelling, and difficulty with foot movement. Management typically involves a combination of conservative approaches and physical therapy.

Symptoms and Diagnosis

Pain and Discomfort

The main symptom associated with Os Peroneum conditions is pain and discomfort in the lateral aspect of the foot. The pain may be aggravated by activities such as walking, running, or jumping. Individuals may also experience tenderness and swelling in the affected area.

Physical Examination

During a physical examination, a healthcare professional will assess the affected foot for signs of tenderness, swelling, and limited range of motion. They may also perform specific maneuvers and tests to evaluate the integrity of the peroneus longus tendon and the presence of an Os Peroneum fracture.

Imaging Tests

Imaging tests such as X-rays, ultrasound, or magnetic resonance imaging (MRI) may be ordered to confirm the diagnosis of an Os Peroneum condition. X-rays can help visualize fractures or abnormalities in the bone, while ultrasound and MRI can provide detailed information about the soft tissues and surrounding structures.

Treatment and Management

Conservative Approaches

Conservative treatment options for Os Peroneum conditions include rest, ice, compression, and elevation (RICE), nonsteroidal anti-inflammatory drugs (NSAIDs) for pain management, and the use of supportive footwear or orthotic devices. Physical therapy may also be recommended to improve foot mechanics, strengthen muscles, and promote healing.

Surgical Interventions

In severe cases, surgical intervention may be necessary. This can involve removing the Os Peroneum, repairing or stabilizing the peroneus longus tendon, or addressing any associated fractures or structural abnormalities. Surgery aims to alleviate pain, restore function, and prevent further complications.

Recovery and Rehabilitation

Recovery and rehabilitation following Os Peroneum treatment typically involve a combination of rest, physical therapy, and gradual return to activity. It is essential to follow the healthcare professional’s guidance and adhere to the prescribed rehabilitation program to optimize healing, regain strength, and prevent re-injury.


Proper Footwear

Wearing proper footwear that provides adequate support and cushioning can help prevent excessive stress on the foot and reduce the risk of Os Peroneum conditions. Shoes with good arch support, shock absorption, and a proper fit can contribute to optimal foot mechanics and minimize the likelihood of injury.

Stretching and Strengthening Exercises

Engaging in regular stretching and strengthening exercises can help maintain the flexibility and strength of the foot and ankle muscles. This can enhance foot stability, improve biomechanics, and reduce the risk of overuse injuries, including Os Peroneum conditions. Consultation with a healthcare professional or a physical therapist can provide guidance on appropriate exercises for individual needs.


Os Peroneum is a small accessory bone with a significant role in foot function. While it may not be present in every individual, understanding its anatomy and associated conditions can contribute to early diagnosis and appropriate management. Whether it is an Os Peroneum fracture or Os Peroneum Syndrome, seeking prompt medical attention and following the recommended treatment plan can lead to successful recovery and a return to an active lifestyle. To learn more about foot conditions and treatment options, visit PrePodiatryClinic101.com.

os peroneum