Two Compartment

Two Compartment

Compartment Syndrome Explained

Compartment syndrome is the result of the tissues in one of the soft tissue limb compartments being deprived of sufficient blood flow due to the pressure in the compartment overwhelming the pressure in the vessels trying to bring blood in. The local tissues can suffer necrosis and die with high levels of pain if treatment is not quickly engaged. The calf and the forearm are the commonest body parts to suffer this as the muscle groups are wrapped up in relatively inextensible compartments bounded by bone and fascia (firm connective tissue). The firm nature of the compartments makes any pressure build up within them potentially dangerous.

The largest cause of compartment syndrome is a tibial fracture, with other causes including other fractures, blood vessel compromise, crush injuries and tight plasters or dressings. Symptoms once compartment syndrome is established are a loss of the pulses, inability to move the part and loss of sensibility. If the doctor suspects that compartment syndrome is present then surgical decompression is the primary treatment. Complications can include muscle breakdown leading to renal failure and Volkmann contracture, an irreversible contracture of the forearm muscles.

Acute onset of compartment syndrome is the most common presentation after a traumatic event, chronic compartment syndrome has been described secondary to excessive exercise by measuring the pressure occurring within the leg compartments. Inside the compartment composed of the muscle and fascia the pressure rises, steadily reducing the blood flow into the area until muscle and nerve damage occurs. Acute compartment syndrome comes on quickly with the irreversible damage following closely after unless it is treated promptly.

Shin splints in athletes have been regularly confused with chronic compartment syndrome, with the pain often on both sides and occurring after a particular period of exertion. The criteria for this condition vary in various pursuits and the abnormality can now be sought by pressure measurements. Open tibial fractures give the highest levels of compartment syndrome, with closed tibial fractures being much less risky for this condition. Vascular injuries may also precipitate compartment syndrome but vascular surgeons typically perform decompression at the time of repair if required.

For compartment syndrome to occur there must be either external or internal reasons for a raised pressure in the segments of the limb. External forces can include over tight clothes or boots and tight dressings or plasters. Internal factors can be numerous and include tissue swelling due to crush injury, fractures or internal tissue bleeding and even overdoing weightlifting. The muscles and the nerves are starved of blood due to the excessive pressure, causing chemical changes due to muscle necrosis which attract greater amounts of water into the compartment, increasing the pressure again. Eventually arterial blood flow is completely obstructed.

The elevation of pressure in the leg compartments needs decompression to be performed quickly or with a delay of six or ten hours there will be widespread tissue and muscle death and significant nerve damage. When muscles suffer damage this results in the release of myoglobin into the bloodstream which can engender renal damage which can be fatal. During exercise there is a volume increase in the muscles, raising the compartment pressures during the chronic type of this condition, keeping the levels high between muscle action and compromising blood flow. Muscle cramps can then occur as they do not get enough blood.

Diagnosis of acute lack of blood to a limb can be indicated by limb pallor, pulse loss, pins and needles, pain and coldness of the leg, however these signs are not reliable in terms of diagnosis in clinical practice. Presentation may be of unexpectedly elevated levels of pain not seemingly related to the injury level, with an aching, deep pain which is worse on muscle stretching. On examination of the limb it should be clear whether there is any likelihood of internal tissue damage. Sensory testing can be helpful as pressure shows more obviously in sensory nerve function.

Fasciotomy is the definitive surgical treatment for compartment syndrome, a cutting into the individual muscle compartments to allow the pressure to dissipate outwards and decompress the areas. The wounds may be left open for some days until the pressure subsides and the tissues recover.

About the Author

Jonathan Blood Smyth, editor of the Physiotherapy Site, writes articles about Physiotherapists, physiotherapy, Physiotherapists in Bournemouth, back pain, orthopaedic conditions, neck pain and injury management. Jonathan is a superintendant physiotherapist at an NHS hospital in the South-West of the UK.

Do two stroke engines mix gasoline and oil and also have a seperate oil compartment?

Please answer above question. Also, I am trying to identify if its a two or 4 stroke. what was can i tell?

Two stroke engines require gas and oil to be mixed but you have to do it before you pour it in the tank. If the engine has a place for oil it is probably 4 stroke.