Compartment syndrome is caused by an abnormal increase in pressure in the tissues contained within a muscle compartment called the compartment. In its chronic form, it occurs on exertion, causing muscle and nerve pain of varying severity. Acute syndrome can also occur following trauma, requiring emergency surgery. Surgery is also a response when no medical solution has been found in chronic forms.

Definition

Compartment syndrome, or compartment syndrome, is the consequence of the increase in intra-tissue pressure in one or more compartments, that is to say in the muscular compartments closed by an inextensible fibrous membrane called aponeurosis which are present in the leg, forearm or hand. This painful pathology can be accompanied by a decrease in blood circulation (ischemia) which increases the suffering of muscle fibers and nerves.

The severity is variable depending on the importance of the overpressure.

In a third of cases, there are muscle hernias: in places, the muscle masses end up coming out of their container through the ruptured aponeurosis.

Causes

Compartment syndrome results from a conflict between the container (the aponeurosis) and the contents (muscle tissue, but also nerves and blood vessels). The increase in muscle volume may be related to muscle contraction, edema or hematoma formation, or even venous or muscle abnormalities. Container abnormalities, for example a thickened aponeurosis following fibrosis or trauma, could also be involved.

In chronic compartment syndrome, the effort directly causes an excessive increase in muscle volume, reversible within a variable time after stopping. The calf is the most frequent location. The attacks are bilateral in 50 to 80% of cases.

The acute form is linked to a sudden increase in pressure following a trauma and / or too much compression by a bandage or a cast, causing engorgement of the muscles. We speak of Volkmann syndrome when it affects a cast forearm. The compression element should be removed as quickly as possible.

Diagnostic

In chronic compartment syndrome, painful manifestations occur during effort only, with regard to the compartment concerned and always identically (same type of effort, same delay).

The physical examination is normal at rest, but the compartments are tense and painful after a stress test (eg on a treadmill) and the muscle hernias harden.

Measurement of intramuscular pressure

The measurement of the intramuscular pressure using a device comprising a needle implanted in the compartment makes it possible to confirm the diagnosis. The classic procedure consists of three measurements: at rest, 1 minute after exercise and 5 minutes after exercise. Normal values ​​at rest are of the order of 15 mm Hg. Pressures above this value more than 6 minutes after exercise, or values ​​which exceed 30 or even 50 mm of mercury just after exercise are considered pathological.

Different tests may be necessary to rule out other diagnoses:

• blood test,
• IRM,
• x-ray,
• Doppler echo,
• scintigraphy,
• electromyogram (EMG) measuring neuromuscular activity.

When clinical signs are sufficient to diagnose acute compartment syndrome, pressure measurement is not necessary and should not delay surgery.

Who is concerned ?

Nine times out of ten people have chronic compartment syndrome. This is most often a young athlete between the ages of 20 and 30. The intensification of the practice is often at the origin of its occurrence.

Manual workers or musicians can suffer from compartment syndrome of the upper limb.

Risk factors

Some sports place excessive and repeated strain on the same muscles and promote the development of compartment syndrome.

Box syndromes in the calf mainly concern long-distance and middle-distance runners or participants in team sports associated with running such as football. Cross-country skiing, brisk walking, roller skating or swimming with fins are also risky sports.

The syndromes of the compartments of the upper limbs can be associated with the practice of motocross, windsurfing, water skiing, climbing …

Chronic compartment syndrome

Pain is the main symptom. Accompanied by a feeling of tension, it forces you to stop the effort. It is of variable intensity and could for example cause a simple limp or on the contrary be very violent.

Abnormal sensations of tingling, numbness or tingling (paresthesias), as well as transient paralysis of the affected compartment may be associated.

The pain gives way more or less quickly at rest, but aches may persist for a few days.

Untreated, compartment syndrome is likely to worsen slowly, with pain appearing with less and less intense efforts, and risk of developing an acute form in which the pain persists after the effort.

Acute compartment syndrome

The very intense or even unbearable pain is cramp or tension type. She is not relieved by a change of position and proves resistant to analgesics. The box is stretched on palpation.

A deficit of sensitivity of the nerve innervating the damaged compartment appears quickly. Paresthesia progresses to loss of sensitivity followed by anesthesia.

If the treatment is delayed, the lack of irrigation (ischemia) causes the disappearance of peripheral pulses and a motor deficit resulting in damage to the muscle and the nerve.

Adaptation of sports practice and medical treatment can overcome chronic compartment syndrome. Surgical treatment can be discussed in athletes suffering from significant discomfort, knowing that stopping sports practice is an alternative. Surgery takes place in the event of failure of medical treatment after 2 to 6 months. It must be practiced urgently in the face of acute compartment syndrome.

Sports prevention and rehabilitation

It involves reducing the intensity of efforts or changing activities, adapting the type of training (stretching, warm-ups), modifying equipment or gestures, etc.

Medical treatment

Venotonic drugs or the wearing of compression socks are sometimes suggested.

Physiotherapy is effective in some cases. It is mainly based on stretching exercises (for the forearm) and on different types of massages.

Surgical treatment

It aims to obtain decompression by opening the compartments concerned (aponeurotomy). The classic intervention requires fairly large skin incisions, micro-invasive arthroscopic surgery constituting an alternative.

Complications (bruises, nerve damage, healing defect, infections, etc.) are rare. In the vast majority of cases, surgery permanently eliminates the pain. After rehabilitation (physiotherapy, walking, etc.), it is generally possible to resume sports activities after 2 to 6 months.

On the other hand, the delay in the management of acute compartment syndrome is accompanied by a major risk of installation of irreversible lesions (muscle necrosis, fibrosis, nerve damage, etc.), with more or less serious consequences: muscle retraction , sensory and motor disorders …

Appropriate warm-ups, stretching exercises as well as sports practice adapted to one’s abilities, with a very gradual increase in the intensity and duration of the efforts, can help prevent compartment syndrome.

When a cast or bandage is too tight, do not hesitate to report it to the doctor.