The patient’s condition is consistent with acute compartment syndrome of the left leg. The patient should undergo emergent fasciotomy/compartment release.
Acute compartment syndrome (ACS) frequently follows trauma to the lower leg and the forearm. Fractures are commonly associated with ACS, although trauma in the absence of bone fracture can also result in ACS. ACS most commonly occurs in the anterior compartment of the lower leg, and often presents with pain on plantar flexion and deep peroneal nerve palsy presenting as foot drop. ACS is more generally associated with pain out of proportion to the injury, paresthesias, firm “woody” feeling, and pulselessness/pallor from vascular insufficiency (note that paresthesias and pulselessness are late findings and not required for diagnosis). Diagnosis typically does not involve blood work, but may include measurement of compartment pressures if diagnosis is not clear. However, in cases where clinical suspicion for ACS is high, manometry is not required to proceed to treatment.
Daniels et al. discuss common hand injuries in the emergent setting. They comment that forearm compartment syndrome can be caused by external compression, circumferential pressure, and increased volume in the compartment from edema or hematoma. They discuss the classic “6 P’s” - pain, paresthesia, paresia, pallor, poikilothermia and pulselessness - and emphasize the urgency of correct diagnosis.
Mauser et al. review the literature on diagnosing acute compartment syndrome and acknowledge the difficulty in proper diagnosis of ACS. They comment that even the gold standard of compartment pressures has been associated with false-positives. They also discuss other methods of measurements and imaging which are still being investigated as possible tools to identify ACS, such as slit catheters, side-port needles, ultrafiltration catheters, ultrasonography, MRI, and near-infrared spectroscopy.
Illustration A is a schematic diagram of compartment syndrome in the leg.
Answers 1, 2, 3: these answers do not contribute to the diagnosis of ACS at this time.
Answer 5: measurement of compartment pressure can be considered if the clinical picture for ACS is unclear.
Daniels JM 2nd, Zook EG, Lynch JM. Hand and wrist injuries: Part II. Emergent evaluation. Am Fam Physician. 2004 Apr 15;69(8):1949-56.
PMID:15117016 (Link to Abstract)
Mauser N, Gissel H, Henderson C, Hao J, Hak D, Mauffrey C. Acute lower-leg compartment syndrome. Orthopedics. 2013 Aug;36(8):619-24.
PMID:23937740 (Link to Abstract)
USMLE Step 2 CK Qbook 4th ed. Daugherty, Stephen R. New York: Kaplan Publishing, 2008.