Anterior compartment syndrome is more often a chronic rather than an acute injury. Runners and other athletes involved in activities that require a lot of repetitive flexion and extension of the foot are most susceptible. Swelling or enlargement of the muscle in the front of the lower leg, causes this condition. Pain, especially when toeing up, and decreased sensation and weakness in the foot may be experienced with this condition. Virtually any injury involving bleeding or oedema formation may lead to compartment syndrome.
Anatomy and Physiology of Anterior Compartment Syndrome
Muscles are covered by fascia, a fairly inflexible fibrous sleeve that encases the muscle and bone. This creates a compartment for the muscle, with the bone forming one side, and the fascia is covering the other sides. In the lower leg, the two bones, the tibia and the fibula, create a more rigid compartment. The tbialis anterior muscle runs over the tibia and fibula and is covered by the fascia. This leaves little room for expansion or swelling of the muscle. When there is increased intramuscular swelling, as a result of trauma or overuse, it creates pressure inside the compartment, which can impede blood flow and function of tissues within the compartment of the muscle.
Cause of Anterior Compartment Syndrome
Acute: Trauma to, or tearing of, the tibialis anterior muscle causing bleeding and/or swelling.
Chronic: Overuse of the muscle causing inflammation and swelling of the muscle pressure in the compartment. Rapid growth of the muscle before the fascia can expand (as seen with anabolic steroid use).
Signs and Symptoms of Anterior Compartment Syndrome
Pain and tightness in the shin (especially the lateral side). Worsens with exercise. Decreased sensation on top of the foot over the second toe. Weakness and tingling may be noticed in the foot.
Complications if Left Anterior Compartment Syndrome Unattended
The pressure int he compartment may lead to permanent nerve and blood vessel damage if left unattended. The underlying cause of the condition will most likely continue to cause irritation and swelling if not treated.
Immediate Treatment for Anterior Compartment Syndrome
Rest, ice and elevation (no compression). Anti-inflammatory medication. Sports massage may be used to stretch the fascia.
Rehabilitation and Prevention for Anterior Compartment Syndrome
Stretching the muscles in the front of the shin will help to alleviate some of the pressure and elongate the muscle. Massage to stretch the fascia may also help to speed recovery. Gradual strengthening and a good flexibility program will help prevent this condition. Avoiding direct trauma to the shin area will prevent acute compartment syndrome.
Long-term Prognosis for Anterior Compartment Syndrome
If treated before damage to the nerves and blood vessels becomes serious, the recovery rate is very good. Acute or severe chronic anterior compartment syndrome may require surgical intervention to relieve the pressure in the compartment.