Introduction

The popliteal artery is a continuation of the femoral artery which originates from the external iliac artery, that being the blood vessel responsible for the majority of the lower limb’s blood supply. The popliteal artery sits in a diamond-shaped space behind the knee called the popliteal fossa, along with one vein, the popliteal vein, and two nerves, the tibial nerve and common peroneal nerve. A range of arterial branches arise from the popliteal artery, predominantly providing blood supply for the region of the knee and some muscles of the leg.¹

The popliteal artery can become compressed within the popliteal fossa, resulting in popliteal artery entrapment syndrome (PAES).² PAES is rare, with the condition only being defined around 40 years ago. This condition can present at birth or develop over many years.³ Signs and symptoms of this condition can vary across patients, though pain in the back of the leg and numbness or tingling in the foot are characteristic features.⁴

Diagnosis of PAES can be made through a doctor taking your medical history and using imaging techniques. Management and treatment for PAES is tailored to the specific signs and symptoms a patient is experiencing, but typically requires surgery.³

Causes of popliteal artery entrapment syndrome

PAES can be present in newborns due to abnormalities in foetal development. Specifically, it is the abnormality of leg muscles development that can cause the popliteal artery to become trapped by leg muscles, leading to PAES.^2,3

PAES may potentially be acquired many years into adulthood, due to physical injury and trauma that can cause the popliteal artery to become compressed. Most cases occur in athletes, who may be particularly prone to physical injury and trauma.^3,5,6

Signs and symptoms of popliteal artery entrapment syndrome

Signs and symptoms of PAES can vary from patient to patient but can include several features:³

• Numbness and tingling in the foot
• Pain in the back of the leg
• Claudication of the foot and leg
• Discoloration of the lower limbs
• Paleness in the lower limbs
• Coolness on touching the lower limbs

Diagnosis of popliteal artery entrapment syndrome

Through a medical history and imaging techniques, a diagnosis of PAES can be confirmed. It is important the the conditions that present similarly to PAES can be ruled out from diagnosis:³

• Compartment syndrome
• Shin splints
• Stress fractures in bones of the legs
• Nerve compression syndrome
• Herniated disk

Medical history

A healthcare professional will take your medical history during a consultation. This involves the doctor asking you questions about why you’re visiting, whether you’ve been diagnosed with previous conditions, whether you’ve undergone prior medical therapies, and other questions related to your health.

This also is an opportunity for a doctor to gain an understanding of the signs and symptoms you are currently facing, helping them to confirm a diagnosis of a condition or rule out other conditions. During a medical history, you have an opportunity to share your concerns and ask questions.⁷

Imaging techniques

A combination of magnetic resonance imaging and ultrasonography can help confirm a diagnosis of PAES as a doctor can visualise abnormalities associated with the popliteal artery that are characteristic of PAES. 

Magnetic resonance imaging uses magnetic fields and radio waves to produce images of the inside of the body. During this procedure, you will be asked to lie in a tunnel-like scanner. This procedure can last from 15 minutes to one hour and a half. The images produced will then be analysed by a medical specialist.

Ultrasonography involves the use of sound waves to produce images of the inside of the body. A small device called a probe is passed over the region of the body being imaged and the medical specialist conducting the procedure can view this on a screen simultaneously. Ultrasounds typically last 15 to 45 minutes.

Management and treatment of popliteal artery entrapment syndrome

Surgery is the mainstay management and treatment option for PAES. Surgical techniques can vary depending on the nature of each individual’s condition. Therefore, consulting with a surgeon can help you identify what procedure may be most suitable for you. Typically, following surgery, imaging techniques will be employed at multiple separate intervals to monitor the success of surgery.³

Complications of popliteal artery entrapment syndrome

PAES can result in complications, which are particularly likely to occur if the condition is not diagnosed or managed and treated in the early stages:³

• Narrowing of the popliteal artery
• Popliteal arterial thrombosis
• Embolisms
• Limb amputation

FAQs

Can physical therapy or exercises help with popliteal artery entrapment syndrome?

PAES can occur as a result of physical injury and trauma, hence why it occurs predominantly in athletes.³ As a result, reducing physical activity may be needed to promote recovery from PAES.⁸ Surgery still remains the mainstay therapy for PAES.³

Can popliteal artery entrapment syndrome be prevented?

Popliteal artery entrapment syndrome cannot always be prevented as it can be caused by abnormalities during foetal development. However, the condition can also result from physical injury and trauma, making it preventable in these cases. Athletes are particularly susceptible to PAES and should pay extra attention to how they can avoid injuries.^2,3

How common is popliteal artery entrapment syndrome?

PAES is a rare condition, affecting 0.17 to 3.5% of the population. The majority of patients affected by PAES, around 85%, are those assigned male at birth. Furthermore, athletes are particularly vulnerable to the condition, with around two thirds of cases of PAES occurring in this population.³

Can someone be born with popliteal artery entrapment syndrome?

Someone can be born with PAES as the condition can result from abnormalities during foetal development. However, even if born with PAES, signs and symptoms of the condition may appear later in life.^2,3

Are there risk factors for developing popliteal artery entrapment syndrome?

PAES is a rare condition but several factors increase one’s risk for developing the condition:⁵

• Those assigned male at birth
• Young adults
• Athletes

Can popliteal artery entrapment syndrome affect both legs?

PAES can affect either or both legs at the same time. However, as PAES is a rare condition, both legs being affected is very unlikely, and the condition almost exclusively occurs in one leg.³

Is surgery always necessary for treating popliteal artery entrapment syndrome?

Surgery is the mainstay therapy for PAES and is typically necessary for treating the condition. Furthermore, it is important that surgery is not delayed to help prevent complications of the condition.³

Are there any lifestyle changes that can help manage popliteal artery entrapment syndrome? 

Most patients with PAES are athletes and may have to reduce their physical activity significantly to help alleviate the condition, though non-athletes may have to adjust their physical activity too. Surgery can help patients return to normality.³

Summary

Popliteal artery entrapment syndrome (PAES) is a rare condition that predominantly affects those assigned male at birth. This condition can present at birth or occur later in adulthood. Signs and symptoms of PAES can vary from patient to patient, though often involve pain in the back of the leg and numbness and tingling in the foot.

The condition can typically be diagnosed through a doctor taking your medical history and using imaging techniques. Surgery is the main mode of management and treatment for PAES, though specific surgical techniques used can depend on a patient’s specific condition. Earlier diagnosis of and management and treatment for PAES can improve outcomes of this condition, decreasing the chances of complications.