<unk>  is diagnosed clinically, based on history and physical examination, though diagnostic imaging such as X-ray may be used to rule out fracture, arthritis, or other causes, based on the person's history and presentation. The modified Eichoff maneuver, commonly called the Finkelstein's test, is a physical exam maneuver used to diagnose<unk> . To perform the test, the examiner grasps and ulnar<unk> viates the hand when the person has their thumb held within their fist. If sharp pain occurs along the distal radius (top of forearm, about an inch below the wrist),<unk><unk> 's syndrome is likely. While a positive Finkelstein's test is often considered pathognomonic for<unk> , the maneuver can also cause pain in those with osteoarthritis at the base of the thumb. Differential diagnosis Differential diagnoses include: # Osteoarthritis of the first carpo-metacarpal joint # Intersection syndrome—pain will be more towards the middle of the back of the forearm and about 2–3 inches below the wrist # Wartenberg's syndrome
De Quervain syndrome
Scaphoid fracture
Lambert–Eaton myasthenic syndrome
Terson syndrome
Achard syndrome
Upper motor neuron syndrome
Brody myopathy
Nance–Horan syndrome