Spontaneous Closed Extensor Tendon Ruptures in the Nonrheumatoid Hand and Wrist.

Extensor tendon disruptions are frequently seen in emergency rooms and hand surgery offices. Traumatic open injuries are more familiar, but spontaneous closed extensor tendon ruptures represent an important clinical entity. Often occurring without any prodromal warning, they can surprise patients and their providers alike. Spontaneous extensor tendon ruptures often occur in the setting of systemic medical conditions or hand and wrist pathology, with the mechanisms that lead to rupture often dependent upon the underlying comorbidities. Remaining knowledge of the factors that place patients at risk of developing these problems is vital to maintain the necessary suspicion to ensure prompt diagnosis and facilitate proper treatment.