Sinus tarsi syndrome

A condition affecting the sinus tarsi of the foot

Overview

Anatomical illustration of the foot, showing the location of the sinus tarsi.

Sinus tarsi syndrome is a condition characterized by pain and tenderness in the sinus tarsi, a small cavity located on the lateral side of the foot between the talus and calcaneus bones. This syndrome is often associated with instability of the subtalar joint and can result from trauma, overuse, or inflammatory conditions.

Anatomy

The sinus tarsi is an anatomical space on the lateral aspect of the foot, bordered by the talus and calcaneus bones. It contains important structures such as the interosseous talocalcaneal ligament, blood vessels, and nerve endings. The sinus tarsi plays a crucial role in the stability and movement of the subtalar joint, which allows for inversion and eversion of the foot.

Causes

Sinus tarsi syndrome can be caused by a variety of factors, including:

• Ankle sprains or other traumatic injuries that affect the subtalar joint.
• Chronic overuse injuries, often seen in athletes or individuals with repetitive foot movements.
• Inflammatory conditions such as arthritis or synovitis that affect the structures within the sinus tarsi.

Symptoms

The primary symptoms of sinus tarsi syndrome include:

• Pain and tenderness localized to the sinus tarsi region.
• Swelling and inflammation around the lateral aspect of the foot.
• A feeling of instability or "giving way" in the foot, particularly during activities that involve weight-bearing or lateral movements.

Diagnosis

Diagnosis of sinus tarsi syndrome typically involves:

• A thorough clinical examination to assess pain, tenderness, and instability.
• Imaging studies such as X-rays, MRI, or CT scans to evaluate the structures within the sinus tarsi and rule out other conditions.

Treatment

Treatment options for sinus tarsi syndrome may include:

• Rest and avoidance of activities that exacerbate symptoms.
• Physical therapy to strengthen the muscles around the foot and improve joint stability.
• Orthotic devices to support the foot and reduce stress on the sinus tarsi.
• Anti-inflammatory medications to reduce pain and swelling.
• In severe cases, surgical intervention may be necessary to address underlying structural issues.

Prognosis

With appropriate treatment, most individuals with sinus tarsi syndrome can achieve significant improvement in symptoms and return to normal activities. However, chronic cases may require ongoing management to prevent recurrence.

Related pages

• Subtalar joint
• Ankle sprain
• Foot anatomy