Allen Kanavel originally described four classic, highly reliable cardinal signs utilized to diagnose acute pyogenic flexor tenosynovitis in the hand. Which of the following specific physical examination findings is NOT considered one of these four defining cardinal signs?

Explanation:
The correct option is d. Kanavel's four cardinal signs are critical for identifying a closed-space flexor tendon sheath infection, a true surgical emergency. They are: 1) severe pain on passive extension (the most sensitive early sign), 2) flexed resting posture to minimize tendon sheath tension, 3) symmetric, uniform fusiform swelling of the entire digit (sausage digit), and 4) exquisite tenderness directly along the anatomic course of the flexor tendon sheath. Palpable crepitus and mechanical clicking at the A1 pulley are the classic hallmarks of stenosing tenosynovitis ('trigger finger'), a non-infectious, mechanical inflammatory condition, not pyogenic infection. Reference: Kanavel AB. Infections of the Hand. Core orthopaedic mcq.