The hand is a vital part of the human body, allowing humans to directly interact with their environment. The functional capabilities of the hand are many because the hand is ultimately an end organ of the human mind. The hand's enormous capacity for adaptability allowed primitive humans to make stone tools and modern humans to pilot complex aircraft.
The human hand is capable of prehension, which involves approaching an object, grasping it, modulating and maintaining grasp, and ultimately releasing the object. When a power grasp is used, the object is pushed by the flexed fingers against the palm while the thumb metacarpal and proximal phalanx stabilize the object. When an object is held with a precision pinch pattern, the object is secured between the pulps of the thumb and index fingers or index and middle fingers.
The hand can touch objects or other human beings while sensing temperature, vibration, and texture. This quality of tactile gnosis is sophisticated enough to allow blind individuals to read the pattern of small elevations that distinguish one Braille letter from another. The hand is also an instrument of communication, whether by making a gesture, playing a musical instrument, drawing, writing, or typing.
General Considerations in Treatment of Hand Disorders
Treatment of hand disorders requires an understanding of normal anatomy and its common variations. Treatment usually attempts to restore the normal anatomy, but when that is not possible, the goal should be restoration of maximal function. The aesthetic appearance of the hand is vital because the hand is usually uncovered and exposed to the scrutiny of others and to the owner. Imperfections are often a source of embarrassment. Effective treatment requires a mature balancing of the need for optimal function and normal appearance of the hand. Complex reconstruction that restores prehension but results in a hideous appearance of the hand is ineffective if the patient is so reluctant to expose the hand that he or she avoids using it. Conversely, a functionless stiff finger leading to awkward motion of an otherwise supple hand may cause the patient more embarrassment than amputation.
When a patient seeks evaluation of a hand disorder, the physician should ask many general questions as well as questions specific to hand function and injury. The chief complaint as perceived by the patient should be summarized in one or two sentences. The patient's hand dominance, age, gender, and occupation should be noted, as well as any hobbies that require hand dexterity or strength. The approximate date of onset of symptoms should be recorded. If injury is the cause of discomfort, the exact date and mechanism of injury should be noted and whether the injury occurred at the workplace. The patient should be questioned about prior treatment and his or her perception of its effectiveness.