This is a case report of tenosynovitis of the second and third extensor tendon compartments of the wrist. The report is unique in that tenosynovitis was evaluated with a combination of gray-scale sonographic images with and without an acoustic standoff pad, real-time examination, and color and spectral Doppler interrogation. Tenosynovitis is a nonspecific, inflammatory process affecting the tendon sheath and may occur as a result of infection, trauma, or inflammatory arthropathy such as rheumatoid arthritis. This case most likely represents an inflammatory type of extensor tenosynovitis. Symptoms, sonographic findings, and treatment options are briefly discussed.