Fulminant Pyoderma Gangrenosum After Outpatient Knee Arthroscopy.

Pyoderma gangrenosum is an immunologic, ulcerative cutaneous condition often associated with systemic disease and frequently precipitated by trauma. It is noninfectious, but the inflammatory assault can resemble a malignant infection such as necrotizing fasciitis. Despite its clinical resemblance to infection, surgical débridement worsens the condition and may remove morphologic clues to the true disease, thus creating a vicious cycle of surgical débridements and disease progression. Furthermore, diagnostic histopathologic and laboratory features are nonspecific, requiring exclusion of other processes. Therefore, appropriate nonsurgical treatment and immunosuppression are commonly delayed, often at a significant cost to the patient. We present a case of pyoderma gangrenosum occurring after outpatient knee arthroscopy that masqueraded as a postsurgical infection. We discuss the diagnostic approach and how a complex reconstruction involving cartilage restoration and soft-tissue coverage was achieved.