Hematogenous Seeding of Traumatized Muscle by Fusobacterium necrophorum: Delayed Compartment Syndrome Following a Sports Injury.

Thigh compartment syndrome after blunt athletic trauma can be difficult to recognize when symptoms evolve in a delayed fashion. We present the case of a previously healthy 20-year-old male football player who developed progressive right thigh pain and swelling after blunt trauma sustained during play. Initial radiographs and venous duplex ultrasonography showed no acute osseous abnormality or deep venous thrombosis, and he was discharged with a presumed soft tissue injury. He returned nine days later with worsening thigh and knee pain, progressive swelling, inability to ambulate, paresthesia, tachycardia, hypotension, leukocytosis, elevated creatine kinase, and elevated lactate. Compartment pressure measurements and clinical examination were concerning for thigh compartment syndrome, and he underwent emergent decompressive fasciotomy. Intraoperatively, purulent material was encountered within the muscle compartment, prompting further evaluation for an infectious process. Subsequent imaging and operative exploration demonstrated a large intramuscular abscess involving the thigh and septic arthritis of the knee. Blood and synovial anaerobic cultures grew Fusobacterium necrophorum. Further history revealed recent pharyngitis, supporting a presumed but unproven mechanism of transient bacteremia with hematogenous seeding of traumatically injured thigh musculature and secondary involvement of the knee joint. Dental disease identified on imaging represented an alternative potential portal of entry that could not be excluded. The patient required serial operative debridement, arthrotomy with irrigation and debridement, targeted antimicrobial therapy, and delayed primary closure. He was discharged in stable condition with close outpatient follow-up and demonstrated clinical improvement. This case emphasizes that delayed progression after blunt extremity trauma should prompt consideration of occult infection, particularly when pain, systemic findings, or operative findings are disproportionate to the presumed injury.