A 20-year-old man with a history of multiple surgeries and revisions of a cleft lip and palate developed right lower extremity pain on the evening following an orofacial procedure (a Le Fort osteotomy). The patient did not report the pain until postoperative day 1, when he noted mild pain on the anterior portion of his right lower leg, including his right knee, ankle, and foot. He also had the sensation that his right leg was swollen. By postoperative day 2, the pain had become unbearable despite multiple pain medications, including oxycodone and intravenous morphine. The patient was unable to walk because of pain in the right leg, but had no symptoms in his left leg.
The patient denied recent trauma to the affected extremity, and had never experienced such pain symptoms before. He also denied numbness, tingling, and weakness in his extremities. Before admission to the hospital for his surgery, he had had no fevers, chills, fatigue, muscle pain, nausea, vomiting, diarrhea, cough, chest pain, joint pain, or rash.
Past medical history.
The patient was born with a cleft lip and palate and had undergone multiple repairs and revisions of these anomalies, beginning at age 4 years.
The patient was receiving no medications at home. His medications while hospitalized included clindamycin (600 mg every 8 hours), oxycodone (10 mg every 3 hours as needed for postoperative pain), intravenous morphine sulfate (2–4 mg every 4 hours as needed), and intravenous dexamethasone (12 mg/day) to mitigate postoperative swelling. Because of both his new-onset leg pain and postsurgical discomfort, he had been receiving narcotics at regular intervals.
Social and family history.
The patient was a student. He had no history of cigarette smoking, did not drink alcohol regularly, and had never used recreational drugs. His father had been diagnosed with colon cancer at age 42 years, and his mother had a congenital corneal disease for which she had undergone a corneal transplant. He had no family history of either inflammatory or metabolic myopathies.
The orthopedics service was consulted on the morning of postoperative day 2 for evaluation of the patient's leg pain. On their examination, the patient was clearly uncomfortable; he was unable to remain still because of the severity of the pain. His blood pressure was 138/90 mm Hg and his pulse was 100 beats/minute. His respiratory rate was 20 breaths/minute, and he had oxygen saturation on room air of 97%. He was afebrile.
Examination of his right leg revealed a tender area over the anterior tibia that was approximately 5 cm in length and 3 cm in width. The skin overlying this painful area of his right leg was unremarkable. Although the patient reported a sensation of marked swelling of his right leg, on examination there was only mild swelling of the right leg when compared with the left. Right knee flexion was reduced by 30° and the range of motion of the right ankle was also limited, both because of pain over the tibia. The medial and lateral joint lines of the knee were nontender, and there was no pain on palpation of the right ankle. There was no effusion, warmth, or erythema of either the knee or the ankle. On strength testing, right hip extension, abduction, and adduction were all 5 of 5. The strength in the extensor hallucis longus, tibialis anterior, gastrocnemius, and peroneus longus muscles was gauged to be 4 of 5, due primarily to pain. His reflexes were 2+ bilaterally at the patellar and Achilles tendons. He had no pain with passive range of motion of his toes. The examination of his left leg was unremarkable, with good strength, full range of motion, and no pain, erythema, swelling, or warmth in any of the joints or soft tissues.
His chest was clear to auscultation, and the cardiac examination showed a tachycardic, regular heart rate with no murmurs. His abdomen had normal active bowel sounds and was soft and nontender. He had no rashes, bruising, petechiae, nodules, splinter hemorrhages, or ulcers of his skin.
The initial laboratory evaluation is detailed in Table 1. The patient's white blood cell count was 25,400/mm3 (normal range 4,500–13,000) on the evening after his surgery. No differential count was performed. He had a hematocrit of 42.3% (normal range 41.0–53.0) and his platelet count was 248,000/mm3 (normal range 150,000–400,000). His blood urea nitrogen level was 12 mg/dl (normal range 8–25) and his creatinine level was 1.0 mg/dl (normal range 0.6–1.5).
Table 1. Laboratory results
Postoperative day 0
Postoperative day 2
Complete blood count
White blood cells, per mm3
Differential count, %
Platelets, per mm3
Plasma urea nitrogen, mg/dl
Liver function tests
Aspartate aminotransferase, units/liter
Alanine aminotransferase, units/liter
Total bilirubin, mg/dl
Direct bilirubin, mg/dl
Creatine kinase, units/liter
C-reactive protein level, mg/dl
Erythrocyte sedimentation rate, mm/hour
A plain radiograph of his right tibia and fibula showed no evidence of a fracture, malalignment, or periosteal elevation (Figure 1).
Because the etiology of the patient's right leg pain was unclear, the rheumatology service was consulted on the afternoon of postoperative day 2. His examination had evolved rapidly. Four hours after the initial orthopedic consultation, the patient's right leg remained swollen and the patient reported worsening pain. There was now tenderness over the entire length of the anterior tibia. Flexion of the right knee and ankle remained limited by pain over his anterior lower leg. The strength of the involved extremity was difficult to assess because of pain, but the patient was clearly unable to dorsiflex his right great toe or to even maintain the position of the toe against gravity: it drooped toward the floor. There was no swelling, warmth, or erythema of the right knee or ankle. In contrast, the left leg was entirely normal, with no evidence of swelling or tenderness and with full range of motion in the joints. The dorsalis pedis and posterior tibialis pulses were 2+ bilaterally.
The patient is a 20-year-old man who experienced acute, progressive right lower leg pain following orofacial surgery. The leg discomfort was accompanied by the rapid evolution of great toe weakness.
There were 3 major entities in the differential diagnosis of this patient's problems: deep venous thrombosis (DVT), an acute infection (e.g., pyomyositis), and a compartment syndrome.
Deep venous thrombosis.
DVT, a common complication among postoperative patients, was considered as an explanation for the patient's presentation. However, DVT is normally accompanied by a greater degree of lower extremity swelling and erythema than our patient exhibited. The development of such a complication appeared unlikely in this patient, because he had been ambulating normally and performing a full range of daily activities up until the day of his surgery. In addition, his pain was over the anterior leg, an unusual site for leg pain secondary to DVT. Nevertheless, DVT remained a possibility, albeit a remote one.
Infectious pyomyositis results from transient bacteremia that seeds damaged muscle tissue leading to a localized infection. Normal muscle appears to be relatively resistant to seeding. Staphylococcus aureus is the most common organism associated with pyomyositis (1). The isolated nature of the patient's report argued against pyomyositis; if the leg swelling had occurred because of septic emboli, additional areas of the patient's body (e.g., his extremities and joints) should have been affected. In addition, he had no evidence of prior muscle injury that would predispose him to this condition. Moreover, the time course of the patient's symptoms argued against an infection related to surgery. He received clindamycin perioperatively, an antibiotic regimen that should have prevented common infections related to surgery.
Compartment syndromes result from a variety of conditions that cause the pressure in a confined fascial space to exceed the perfusion pressure, thereby leading to tissue hypoperfusion and injury. Most compartment syndromes are caused by trauma. Tibial fractures are the most common fracture implicated in extremity compartment syndromes. However, there has been increasing recognition of an entity known as atraumatic limb compartment syndrome. This uncommon entity is reported most often following prolonged surgical procedures, usually those conducted with the patient in the lithotomy position. Clinical sequelae of compartment syndromes are acute nerve and muscle ischemia, myocyte necrosis, and rhabdomyolysis.
The most common type of compartment syndrome occurs in the lower leg. The superficial and anterior compartments are the most susceptible. Atraumatic compartment syndrome of the lower leg anterior compartment was viewed as the most likely cause of this patient's constellation of symptoms. The anterior compartment includes the extensor hallucis longus muscle, which is innervated by the deep fibular nerve, the prime dorsiflexor of the great toe.
INITIAL MANAGEMENT AND HOSPITAL COURSE
The findings of increasing leg pain, pain out of proportion to examination, and the new inability to dorsiflex the right great toe led to emergent re-consultation with orthopedics for the measurement of compartment pressures.
The pressures in the superficial and posterior compartments (Figure 2A) were 4 mm Hg and 6 mm Hg, respectively. Normal compartment pressures vary from 0–4 mm Hg at rest and 8–10 mm Hg with exercise. In contrast, the pressures in the lateral and anterior leg compartments were 17 mm Hg and 45 mm Hg, respectively. These data fit well with the clinical scenario, and were diagnostic of a compartment syndrome.
The patient's laboratory examination was remarkable for a serum creatine kinase level of 8,667 units/liter (normal range 60–400). In addition, the serum aminotransferase levels were also elevated, with an alanine aminotransferase level of 148 units/liter (normal range 10–55) and an aspartate aminotransferase level of 238 units/liter (normal range 10–40). One week earlier, his serum aminotransferase levels had been normal. His urinalysis results showed no protein or red blood cells (Table 1).
A magnetic resonance imaging (MRI) study of the right lower leg performed prior to compartment pressure measurements (Figure 2) showed edema and swelling of the muscles within the anterior compartment. The edema and swelling were most pronounced in the middle and distal aspects, and predominantly involved the tibialis anterior and extensor digitorum longus muscles. There was also a small amount of fluid within the adjacent superficial and deep fascia.
The patient was taken to the operating room for emergent surgical debridement. The surgeons incised the fascia of the anterior and lateral compartments along nearly their entire lengths. The lateral compartment and the upper half of the anterior compartment appeared pristine to inspection. However, over the distal third of the tibia, the color of the tibialis anterior muscle changed from bright pink to dusky purple (Figure 3). Bovie stimulation of the purple areas elicited no contractions. These findings suggest that the dusky areas were no longer viable. This tissue was removed by manual dissection, and the wound was closed.
A muscle specimen from the extensor hallucis longus at the initial debridement showed necrosis and focal intramuscular acute inflammation and hemorrhage (Figure 4). A Brown-Hopp stain was negative for organisms.
Acute atraumatic compartment syndrome.
Compartment syndromes occur when increased pressure develops within a defined anatomic space. The increased pressure leads to decreased perfusion and eventually tissue ischemia (2). The most common site for compartment syndromes to occur is in the lower leg. The superficial and anterior compartments are affected most often (3).
Compartment syndrome can occur acutely or subacutely, and is often precipitated by the development of hemorrhage or edema. Conditions commonly associated with compartment syndromes are fractures, trauma, circumferential burns, venous and/or arterial obstruction, reperfusion injuries, excessively tight dressings, infections, prolonged extremity immobility under pressure, intracompartmental hemorrhage, intense exercise, and seizures (2). Several cases of atraumatic, “well-leg” compartment syndrome have been reported following surgery in the lithotomy position (4–7). These cases have been associated with a variety of surgical procedures, including abdominal operations, cytoreductive surgery, and radical hysterectomies or prostatectomies. Cases have also been reported after uncomplicated labor and delivery (8).
Potential risk factors for the development of atraumatic compartment syndrome after surgery are the length of the procedure (>5 hours), decreased perfusion of the lower leg because of either Trendelenberg or lithotomy positioning during surgery, and inadvertent external compression of the lower leg (e.g., through the malfunction of pneumatic boot compression devices) (5). Fluid shifts following prolonged periods of immobility are also postulated to contribute to the development of compartment syndromes. Although our patient's orofacial surgical procedure lasted approximately 7 hours, he had not been placed in either the Trendelenberg or lithotomy positions, and there were no other known precipitants of compartment syndrome such as intraoperative compression of the legs.
The diagnosis of compartment syndrome is made by history and physical examination. Compartment syndromes are often recognized by their association with “5 P's”: pressure, pain, paresthesia, paresis, and pulselessness (1). Paresis and pulselessness are late findings that often signal irreversible damage.
One salient feature of this syndrome is pain that is both severe and out of proportion to the clinical examination. In patients with compartment syndrome, the symptoms are generally exacerbated by movements that stretch muscles passively (9). Narcotic analgesics are frequently insufficient to control the pain.
The lower leg consists of 4 compartments: anterior, lateral, posterior, and superficial (Figure 2A). As noted, the measurement of pressures within the compartment confirms the diagnosis. Although experts do not agree upon a standard threshold of pressure above which surgical debridement is indicated, 3 types of findings tip the balance in favor of immediate surgical intervention: unequivocal clinical findings of the compartment syndrome, compartment pressures within 20 mm Hg of the patient's diastolic blood pressure and within 30 mm Hg of the mean arterial pressure, and steadily rising compartment pressures on serial examinations (2). A compartment pressure of 30 mm Hg for 8 hours has been found to induce muscle necrosis (10).
The anterior compartment contains 4 muscles: tibialis anterior, extensor digitorum longus, extensor hallucis longus, and fibularis tertius. These muscles are the main dorsiflexors of the ankle joint and extensors of the toes (11). The nerve that innervates all of these muscles is the peroneal nerve. Our patient's inability to dorsiflex the great toe was likely initially due to both nerve and muscle ischemia, followed by infarction and damage of both structures.
MRI can be helpful in cases in which the clinical findings are ambiguous; i.e., where no clear source of trauma or injury exists as a potential precipitant (12). MRI can also identify compartments at risk by visualizing edema within the affected muscle compartments. Edema presents as areas of high signal intensity on T2-weighted images (Figures 2B and 2C). However, this finding is nonspecific, and must be interpreted in light of the clinical situation. Pathologic examination of biopsy material is most useful when the underlying diagnosis is unclear. Infectious etiologies must be excluded by appropriate stains and cultures.
In summary, acute atraumatic compartment syndrome must be considered promptly in a patient who develops sudden leg pain after surgery. This condition is a surgical emergency. Swift diagnosis and timely surgical intervention are essential to the prevention of significant morbidity.
The patient returned to the operating room 4 days later for split-thickness skin grafting to close the incised areas. At that time, most of the tissue remaining in the anterior compartment was reported to be viable. However, the remainder of the extensor hallucis longus still appeared dusky, and was removed. Several days after surgery, the patient's creatine kinase levels returned to normal, and he was discharged home.
Dr. Liao had full access to all of the data in the study and takes responsibility for the integrity of the data.
Acquisition of data. Liao, Gaut, Huang.
Analysis and interpretation of data. Liao, Gaut, Huang.
Manuscript preparation. Liao, Gaut, Huang, Cohen.
We would like to thank Dr. Andrea Burke for providing the intraoperative photograph and Dr. Daniel Richardson for providing details on the surgical procedure and perioperative management.