No anatomical feature combines strength, functionality, beauty, and expressiveness to a greater degree than the human hand. The ability to move the thumb in relation to the other fingers is a physical feature unique to the human species. The hand can contribute to remarkable feats of strength, while performing extremely delicate fine-motor functions. The injuries that are sustained to the hand in sport range from those that are an irritation, to those that cripple.
The hand comprises 27 bones and 27 muscles, including the wrist joint. Individually, the bones are small and vulnerable to injury, but when constructed into the complex structure of the hand, these bones are part of a strong, seamless unit. The bones of the wrist are the carpals, which meet the ulnar and radius (the bones of the forearm) to create the wrist joint. In the opposite direction, the carpals link to the metacarpals to form the skeletal aspect of the palm of the hand; the metacarpals extend to the fingers, joining the bones, called the phalanges, in each finger. The joints created at the intersection between the fingers and the bones of the palm are the metacarpophalan-geal joints, or the knuckles. A frictionless substance, articular cartilage, located at the end of each bone in the hand, assists in the movement of each finger and joint. Ligaments connect each of the bones. The larger muscles of the hand begin in the forearm, with the smaller muscles employed in the movements of the thumb are connected to the carpals in the wrist.
The hand also contains three nerve pathways, the largest of which, the median, runs through the carpal tunnel at the wrist. The hand is supplied by blood through a series of arteries that run through the wrist, palm and fingers.
As the hand and its structural complexities are employed in one respect or another in almost every conceivable sport, the exposure to injury and the range of damage that might be sustained to the hand is almost unlimited. It is possible for any bone to become fractured, or any ligament to be sprained or torn.
Examples of the more common hand injuries include: gamekeepers thumb; rupture of the scapholunate ligament; fracture of the scaphoid bone; finger dislocation; injury due to unexpected force; carpal tunnel syndrome; blisters and lacerations; and tendonitis.
Gamekeepers thumb is a rupture of the ligament forming the palm side of the thumb joint; this injury occurs when the thumb is jammed forcefully away from the palm through either a fall, or an object such as a ball is driven against it. As with all forms of hand surgery, the procedures are delicate and the rehabilitation must be unrushed and carefully monitored.
The scapholunate ligament, which is positioned across the top of the wrist, can be ruptured by a fall onto an outstretched hand. This injury is a serious event, and will often necessitate surgery. Located at the wrist is the scaphoid bone; a fracture to this bone is common in falls in cycling, where the rider puts out a hand to stop the fall. If this injury is not detected immediately, as it is often mistaken for a simple sprain, the scaphoid can become diseased due to the onset of necrosis, a death of the bone structure.
Any finger can become dislocated due to force being applied to it; in everyday parlance, athletes speak of fingers becoming "jammed." Sprains and dislocations of the smaller finger joints can usually be corrected through splinting and immobilization of the joint; dislocations of the larger joints, such as that at the base of the thumb or the individual fingers, will often require surgical repair to mend the ligament that often becomes torn, to hold the displaced bone in proper position. The bone immediately above the wrist and below the fourth and fifth finger can be fractured through the unexpected application of force, such as experienced by a golfer who grounds the golf club.
If the carpal bones and ligaments creating the carpal tunnel become compressed onto the median nerve, the function of the hand can be significantly compromised. This condition is known as carpal tunnel syndrome.
The position of the hand renders it vulnerable to abrasions, cuts, and lacerations of all manner of severity. Blisters occur on the skin of the hand in sports such as baseball and cricket, where a ball is delivered with both force and spin, causing repetitive friction across the skin. The tendons of the hand are also vulnerable to tendonitis, a condition resulting chiefly from repetitive motions that cause strain and resulting fatigue in the tendon fibers.