Compartment Decompression

What is Compartment Decompression?

Compartment decompression, also called ‘decompressive fasciotomy’, is a surgical procedure to treat a painful knee condition known as “compartment syndrome”.

Overview of Compartment Syndrome

Your knee is divided into three major compartments: 

• Medial compartment (the inside part of the knee) 
• Lateral compartment (the outside part of the knee) 
• Patellofemoral compartment (the front of the knee between the kneecap and thighbone)

These compartments have a mass of muscle tissues, blood vessels and nerves surrounded by a strong, non-expandable band like membrane called fascia. Any sort of injury to the knee joint results in bleeding or swelling within the compartments.

This can lead to a build-up of a large amount of pressure inside the compartments and subsequent injury to the muscles, blood vessels, and nerves. The condition eventually results in compartment syndrome.

Causes of Compartment Syndrome

Total knee arthroplasty (surgical reconstruction or replacement of the knee) is the major cause of compartment syndrome. Other causes include:

• Traumas such as contusions or fractures
• Vascular damage or diseases
• Complex previous surgery 
• Deep-vein thrombosis (blood clotting)
• Soft tissue compromise 
• Venous insufficiency 
• Use of tourniquets 

Indications for Compartment Decompression

Increased pressure inside the compartments can lead to a decreased or total stoppage of blood flow to the muscle tissues and nerves. This can result in: 

• Muscle or nerve damage
• Cellular death (necrosis)
• Long-term disability 

Therefore, early recognition and prompt decompression of the compartments are necessary. The compartment decompression procedure should be recommended when the compartment pressure exceeds 30 mmHg to 35 mmHg.

The Procedure 

Compartment decompression is the most preferred surgical treatment for compartment syndrome. Early diagnosis and surgical decompression will significantly reduce morbidity and mortality besides positively influencing the recovery from the surgery. 

During the surgery:

• You will be placed in a supine position on the operating table. 
• An inflated tourniquet is applied to your thigh.
• General anesthesia with prophylactic antibiotics is administered.
• An incision is made in the skin towards the fascia.
• The fascia covering the affected compartment is then cut open. 
• The affected compartment is decompressed to reduce the pressure.
• The incision is closed after the swelling decreases.
• If necessary, a skin graft is performed to close the incision. 

Prognosis

Clinically, early decompression of compartments has proven to be associated with a good outcome. If the incisions are small and the procedure is performed within eight hours of the development of symptoms, you can usually return to your regular activities faster.