First dorsal interosseous muscle atrophy is a common clinical manifestation of intrinsic hand muscle dysfunction. Its etiology is complex， involving damage to multiple components such as motor neurons， cervical nerve roots， brachial plexus nerves， and the deep branch of the ulnar nerve. Neurophysiological techniques， as core technologies for assessing neuromuscular function， are particularly crucial for localizing the diagnosis and differentiating the causes of this condition.This paper reviews current diagnostic strategies for first dorsal interosseous muscle atrophy using neuroelectrophysiological techniques， enhancing diagnostic accuracy and efficiency through systematic testing protocols. The strategy emphasizes starting with medical history and physical examination， followed by targeted needle electromyography （EMG） and nerve conduction velocity （NCV） testing. Key focus is placed on muscles innervated by the deep branch of the ulnar nerve， the recurrent branch of the median nerve， and the C8/T1 nerve roots. This approach enables precise localization from peripheral to central， and from distal to proximal， providing reliable objective evidence for formulating clinical treatment plans.