Compartment syndrome is a challenging problem to work with. Early diagnosis and proper treatment are required to save the affected limb. Without appropriate care, the patient with compartment syndrome could be at risk for death.
In this review article, orthopedic and hand surgeons from Duke University (North Carolina) bring us up-to-date on all aspects of this condition. They provide a brief history of compartment syndrome (first described in 1881). A definition for the condition and review of the anatomy of the various compartments of the arm are included.
Medical and surgical strategies for treatment based on pathophysiology (what went wrong at the cellular level) are a main feature in this review. Drawings, photos, MRIs, and X-rays are used to help the reader visualize the problem and the solution.
Just what is the problem? Compartment syndrome describes a condition in which fluid (swelling or blood) builds up inside one or more of the individual compartments of the arm.
Traumatic injuries, especially bone fractures that puncture the soft tissues are a common cause of compartment syndrome. A splint or cast that is too tight can also cause this problem. The use of a tourniquet during surgery (or with drug abuse) can contribute to compartment syndrome. Other causes include surgery for blood clots, bypass surgery, trauma from electrical or chemical burns, crush injuries, and snake bites.
The “compartments” are easier to understand if you think of each group of muscles and tendons as being surrounded by a protective sheath or lining of connective tissue called fascia. There are individual compartments on the front and back of the upper arm, forearm, hand, and fingers.
In each compartment, the fascia fits closely to the outer layer of the soft tissue it surrounds — like a sleeve or envelope. The structures are lubricated with a glistening fluid that allows everything to slide and glide against each other. There isn’t a lot of give or room for increased volume of fluid from swelling.
When an injury occurs that leads to swelling, the increased pressure inside the sleeve or envelope cuts off blood supply to the muscles. The muscle cells start to necrose or die. Left untreated, this necrosis can progress to the point of gangrene.
At the same time, other soft tissue structures inside the compartment such as nerves can get pinched or compressed. The effect is like a crush injury with damage to the nerves. All of these effects can be irreversible (permanent).
Surgeons use several key tools to diagnose the problem. The patient history (what happened, when it happened, and how it happened) and clinical presentation (what the arm looks like) to get started. Various tools (catheter, manometer, Doppler flowmetry) are available to help measure the pressure inside the compartments.
Treatment hinges somewhat on the results of findings. For example, length of time since the injury, amount of pressure, and length of time soft tissues have been under increasing tissue pressure.
Research on this problem has shown that effects are reversible if stopped before eight hours of ischemia (loss of blood supply). Cells start to die at an alarming rate after four hours without blood delivering needed oxygen.
No one knows for sure exactly what level of tissue pressure must be sustained before permanent damage occurs. Based on current evidence and clinical experience, a general guideline is that surgery is needed when the compartment pressure is 20 to 30 mm Hg higher than the diastolic blood pressure. Just using the compartment pressures without comparing them to the blood pressure may be a less reliable method of determining when surgery is needed to release the pressure.
Treatment may begin with just taking pressure off the arm whenever and however possible (e.g., loosening bandages, splint, or cast if that’s the problem). Most of the time, early surgery is indicated.
The surgical procedure for this condition is called compartment decompression or fasciotomy. The surgeon slits open the skin and first layer of fascia called the epimysium. Once the upper layers of fascia have been released, the surgeon conducts a careful search of each compartment for any other areas of restriction.
The procedure does involve direct release of all layers of fascia involved and debridement (removal of any tissue that has died). In some cases, it may be necessary to release tight tissues from around nerves passing through the compartments. The authors provide surgeons with detailed descriptions of their preferred surgical approaches for incisions, decompression, and debridement.
Serious complications can occur without treatment. Death of muscle tissue eventually leads to replacement with scar tissue called fibrosis. Fibrosis is stiff and unyielding. It can apply additional pressure on nearby soft tissue structures, including nerves. Tight tissues lead to contractures (muscles no longer stretch) and loss of joint motion. The final outcome can be chronic pain, loss of sensation, and loss of function.
With treatment, the results are generally good. Prognosis does depend on how soon an accurate diagnosis is made and treatment started. But there are some factors that affect the final outcomes including severity of injury (e.g., damage to the soft tissues from the injury) and length of time with elevated pressures.
Loss of blood supply, involvement of nerve tissue, and patient’s overall general health can also make a difference. The presence of other health problems (heart disease, diabetes, blood clotting disorders) can complicate matters.
There are many challenges for patients and surgeons when treating compartment syndrome. Patients with this condition must be prepared for a long course of treatment followed by months of rehabilitation. Repeated surgeries are often needed to clear out all dead tissue. Infection, poor wound healing, and open wounds in need of skin grafts further complicate recovery.