Bilateral knee arthrodesis in a patient with common variable immunodeficiency.

Patients with common variable immunodeficiency can present with debilitating arthritis. We present the case of a 42-year-old man with bilateral knee arthritis who underwent a right total knee arthroplasty that subsequently became infected. Five months after resection arthroplasty, his right leg spontaneously fused in extension, but his left knee was limited to an arc of motion between 90° and 110°. At the patient's request, he underwent a noninstrumented arthrodesis of the left knee. The patient now has bilateral arthrodeses and ambulates with a cane. While arthroplasty may be attempted in such patients, the increased risk of infection may potentially result in arthrodesis, possibly without instrumentation.