Hand anatomy and function are highly complex. The thumb alone is controlled by nine individual muscles, which are controlled by the radial, median, and ulnar nerves. The thumb movement is so complex that there are six unique descriptive terms for describing only the direction of the thumb joint at the base of the thumb. If you play an instrument, such as the guitar or the piano, you are likely aware how the slightest ache or pain affects your finger positioning required to play those instruments.
Hand and wrist have twenty seven bones. The hand is innervated by the median, ulnar, and radial nerves, which have sensory and motor components. The muscles of the hand are divided into intrinsic and extrinsic groups while the tendons are divided into flexors and extensors.
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