Originally published June 2014
Traumatic compartment syndrome of the lower limb is a serious clinical problem. It happens most commonly after major trauma or fracture. However, it may also occur after minor trauma or for other reasons. Early diagnosis is often challenging. Due to its rapidly evolving and aggressive nature, delays in diagnosis frequently lead to poor clinical outcomes for patients.
From 2003–2013 the CMPA closed 66 cases involving compartment syndrome. Most cases were related to traumatic leg injury or its repair, but the condition was also seen as a complication of surgeries such as tibial osteotomy, revascularization procedures, and cosmetic calf augmentation. A few cases were exercise-induced or spontaneous in nature, rendering a tough diagnosis even more difficult. The vast majority of patients in these cases were left with permanent injury including major scarring, foot drop, and in a few cases, amputation.
Since compartment syndrome is a recognized complication of trauma and certain types of surgery, the poor outcomes in some of the cases were not always the result of the care provided. However, the condition continues to be an area of increased risk, with about half of the cases resulting in an unfavourable medico-legal outcome for physicians. Unfavourable medico-legal outcomes for physicians were often associated with delays in diagnosis that resulted in permanent injury. Some resulted from a performance issue during surgery (e.g. vascular injury during tubal ligation or improperly performed calf augmentation).
In the cases where the care was criticized, communication breakdown between healthcare providers was the most common issue. Inadequate monitoring or documentation, and failing to include compartment syndrome in the differential diagnosis were also associated with poor outcomes. Failing to include the risk of compartment syndrome in the consent discussion was an issue in several cases.
Case 1: Atypical presentation leads to a delay in diagnosis
A 31-year-old is brought to the emergency department (ED) of a community hospital by ambulance after collapsing during exercise. He complains of pain in the front of both lower legs with numbness and weakness. His legs are tense, with pain on passive inversion of the ankle.
The physician suspects exertional compartment syndrome and consults an orthopaedic surgeon who recommends conservative management and overnight observation. There is no improvement overnight despite liberal doses of narcotics. Another physician reassesses the patient and determines that he has severe shin splints. The patient, still in considerable pain, is discharged.
Later that day, the patient visits his family physician complaining of increasing pain. The physician prescribes a NSAID and makes an elective referral to a sport medicine specialist.
After 2 more days pass, the patient presents to another community hospital ED. The emergency physician notes marked bilateral weakness of ankle dorsiflexion and eversion. The patient is discharged with instructions to attend a hospital with an on-site orthopaedic service if symptoms persist.
A few days later, the patient presents to a large university centre where bilateral compartment syndrome, bilateral foot drop, and rhabdomyolysis are diagnosed. The condition is considered too advanced for treatment with fasciotomies.
The CMPA pays a settlement to the patient on behalf of several member physicians for failing to consider the diagnosis.
Compartment syndrome explained
Compartment syndrome results from increased pressure within a limited anatomical compartment, which can compromise the viability of muscles, nerves, and other tissues within that space. It most commonly occurs in the lower leg, however the forearm, hand, thigh, foot, and buttock are other possible sites.
When it develops in the lower limb, it is most often related to tibial fractures and soft tissue injuries. However, it can also occur in the context of surgical positioning ("well limb" compartment syndrome).
Compartment syndrome may be characterized by narcotic-refractory pain out of proportion to the apparent degree of injury or physical findings, altered sensation, pain on passive stretch, weakness, and palpable tenseness of the compartment. Given that most compartment syndromes occur as the result of a fracture, the assessment of the origin of the pain is often problematic. In addition, physical examination of the limb may be limited by large dressings or casts.
To date, no reliable clinical guidelines for the diagnosis of compartment syndrome have been established. Pressure measurements of the compartment can be helpful in establishing the diagnosis. Once identified, fasciotomy is necessary to relieve compartment pressures and preserve compromised tissues. The patient's outcome is influenced by the length of time from the onset of symptoms to the time of fasciotomy.
Case 2: Analgesia masking pain
An orthopaedic surgeon evaluates a 4-year-old who is recovering from bilateral tibial osteotomies. She is receiving epidural anaesthesia. He notes that her toes are pink and she has no pain on passive motion. He transfers care to the on-call orthopaedic surgeon before leaving for the long weekend.
While making rounds later that day, the on-call orthopaedic surgeon notes that the patient's right foot is swollen, but she otherwise appears fine. A few hours later, a nurse calls him with concerns about continued swelling and breakthrough pain. Over the telephone, he gives an order to bivalve the cast, which is done by the orthopaedic technician 1 hour later. The patient's epidural is removed, and intravenous analgesia is increased in an attempt to alleviate the patient's pain.
The next day a resident is called about continued swelling of the patient's right foot and leg. He notes that the bivalved cast is taped tightly, but the patient shows no sign of pain with limited passive motion, and her toes are pink with good capillary refill. He re-wraps the bivalved cast loosely and orders that neurovascular signs be evaluated every hour.
The original orthopaedic surgeon examines the patient on his return to hospital 3 days post-surgery. He believes she is showing signs of neuropraxia and orders observation. However, several weeks post-discharge, it is determined that the patient had experienced compartment syndrome, and is left with permanent foot drop.
The CMPA pays a settlement to the patient on behalf of the physicians for failing to recognize that the epidural could mask compartment syndrome pain.
As pain is a cardinal sign of compartment syndrome, continuous epidural analgesia and patient-controlled analgesia may be associated with "pain masking," making the diagnosis more difficult. While there is controversy regarding what types of analgesia are most associated with pain masking, some hospitals are re-evaluating regional anaesthesia in patients at risk for compartment syndrome.
Risk management considerations
The following risk management suggestions are based on the expert opinions in these cases:
- Consider the risk of compartment syndrome in patients presenting with extremity injuries or a history of recent surgical procedures.
- Consider compartment syndrome in the differential diagnosis of patients with cardinal symptoms and signs even in the absence of a fracture or injury.
- If compartment syndrome is a risk of a proposed surgery, consider including that possibility in the consent discussion.
- Conduct the appropriate neurovascular assessments when evaluating a patient at risk for compartment syndrome.
- Consider if analgesia is masking the pain of the disorder.
- Consider whether the patient requires emergent investigation for compartment syndrome.
- Other healthcare providers should know the changes in the patient's condition that would require immediate attention and notification.
- When discharging a patient at risk for compartment syndrome, give clear instructions as to the symptoms and signs that warrant seeking further medical attention and the urgency of such evaluation.
- Thoroughly document patient assessments, including complaints of pain, analgesic requirements, and the neurovascular examination.