The fist closure is involved in many activities that are needed in everyday life. Diseases or disorders can cause severe impairments.
What is the fist closure?
In the great fist closure, the index, middle, ring, and little fingers are flexed to such an extent that the fingertips reach the palm and the inner surfaces of the distal, middle, and proximal phalanges come into contact with each other. In the large fist closure, the index, middle, ring, and little fingers are flexed so much that the fingertips reach the palm and the inner surfaces of the distal, middle, and proximal phalanges come into contact with each other. Flexion in the middle and end joints of the fingers is maximal, and submaximal in the base joint, as contact stops further movement. Finally, the thumb is placed diagonally over the index finger. The complete execution of the fist closure is possible only with a certain amount of force applied by the finger flexors and the muscles that bring the thumb into opposition. The position of the wrist affects the functional possibilities. Execution with a slight extension (dorsal extension) is often unconsciously preferred because the mechanical efficiency of the executing muscles is greater and the opposing muscles (finger extensors) release the movement better. This type of execution is called functional hand. The use with a flexion (palmar flexion) is also possible, but less powerful. The small fist lock represents a residual function when the base joints of the fingers can no longer be flexed. Some activity is still possible due to maximum flexion in the other finger joints.
Function and task
Fist closure is an indispensable requirement for many daily, occupational, and athletic activities. These include all movements used to grasp, hold, and move objects of relatively heavy weight, while light things can also be held and guided with other forms of grasp. Typical activities involving a fist grip activity occur when an object is grasped and moved with a handle or similarly shaped object. In the household, these are activities such as mopping, vacuuming or sweeping; in gardening, they are digging, hoeing or working with a rake. The same applies to many craft activities. Bricklayers, plasterers, tilers or painters also use many tools with handles of different lengths and shapes for activities on the floor, wall or ceiling. The same type of fist activity occurs in all backstroke sports such as tennis, squash and badminton. It is noticeable that whenever a lot of stability is needed in these functions, the functional hand is the preferred version. This is due to the more favorable mechanical conditions offered by this type of realization. In motion sequences, on the other hand, the wrist is dynamically brought into palmar flexion, such as in the forehand or butterfly strokes in the backstroke sports or the movement of a dumbbell in weight training. A characteristic of all the types of activity described is that the objects being held prevent complete fist closure, yet muscle activity is present to the fullest extent. It is different in boxing and other martial arts when they are performed without gloves. The stable fist lock is utilized in its complete execution to position the bony parts of the fingers well to perform effective actions against an opponent or objects. This hand position can also be used as a threatening gesture to either deter possible attackers or to instill fear in the opponent.
Diseases and ailments
The prerequisite for the execution of the fist lock is functional finger joints and muscles. All injuries in the area of the fingers can impair or completely prevent it. Bruises, sprains, torn ligaments or fractures in this area occur relatively frequently in sports or in working life. In addition to the direct consequences in the case of a fracture, it is often pain that limits mobility in the joints and does not allow fist closure. The functionality of the hand can be significantly limited as a result. A typical hand disease that can affect fist closure is tendonitis. It is a typical overuse syndrome that can affect the long end tendons of the finger muscles, among others.If the extensor tendons that run along the back of the hand to the fingers are inflamed, fist closure is often made impossible. When the fingers are flexed, the tendons are stretched and the acute increasing pain limits movement. A similar effect can occur with so-called tennis elbow, in which the origins of the dorsal and finger extensors are painfully irritated. In this condition, too, the described stretching pain can prevent fist closure. In addition, assuming the correct position in the wrist for the functional hand is impaired, due to contraction pain that occurs. A complete or incomplete failure of the finger flexors leads to the fact that the fist closure cannot be executed completely or not at all. A typical disease in which this mechanism occurs is the so-called carpal tunnel syndrome. In this condition, the median nerve, which supplies the finger flexors, is pinched in the carpal tunnel in the wrist area. The muscles of the first 3 fingers increasingly lose their flexor function and remain in moderate extension. Because of its typical appearance, this phenomenon is called sworn hand. Clasping the fist is no longer possible. Chronic polyarthritis is a rheumatic disease that initially affects the small joints. On the hand, the wrist and finger joints are typically affected. The inflammatory process in this autoimmune disease, which occurs in stages, leads to the gradual destruction of the affected joints. All hand and finger functions are affected by this process, including fist closure. With increasing duration, this disease leads to massive loss of function.
