Dr Jason Toniolo

Popliteal Entrapment Syndrome

Popliteal entrapment syndrome occurs when the popliteal artery (behind the knee) is compressed by surrounding muscles or tendons, reducing blood flow to the lower leg.

It usually occurs due to anatomical abnormalities that pertain to how the artery develops during its embryonic stages. Sometimes, there are ‘functional’ entrapments, which means no anatomical abnormality is identified, but there is some other cause for the artery being compressed and compromised.

Symptoms

Pain, cramping, and numbness in the calf, especially during exercise, and coldness or discolouration of the foot.

Differential diagnosis

  • There are other causes of similar symptoms in the leg, which are not from popliteal entrapment. These include
  • Cystic adventitial disease
  • Iliac artery endofibrosis
  • Fibromuscular dysplasia
  • Burgers disease (damage to the artery from the immune system brought on by smoking)
  • Vasculitis (autoimmune blood vessel diseases)

Chronic exertional compartment syndrome

treatment options

Surgery to release the trapped artery is often recommended to restore proper blood flow and prevent complications. 

There are six main types of popliteal artery entrapment, each with a different surgical solution. A thorough imaging investigational workup is required to diagnose the abnormality and plan intervention.

Prior to surgery, the following investigations may be requested:

1. Arterial and venous duplex (ultrasound) with provocative manoeuvres

2. MRI to delineate any abnormal anatomy. This helps plan the correct surgical approach

3. Arterial angiogram with provocative manoeuvres to confirm any requirement for arterial reconstruction, if there is evidence of damage to the popliteal artery

Surgery

The two surgical approaches include either:

1. A medial approach (on the side of the calf that faces the other leg)

2. A posterior approach (around the knee crease)

Each approach has its advantages and disadvantages, and is selected based on the anatomical problem identified on imaging.