Baseball Finger, also known as Mallet Finger, is a condition that occurs when one of the tendons that assist in straightening out the finger is damaged. This damage can occur from the jamming or forceful bending down of the fingertip. Symptoms include swelling and tenderness around the fingertip.

Those at Risk
Though it is called Baseball Finger, the injury can also occur while playing football and basketball as well.

Diagnosis
A Baseball Finger is diagnosed once the manner in which the injury was incurred is discussed and the last knuckle and extension of the finger are physically examined. An X-ray may also be indicated in order to determine if the finger bone was damaged during the force.

Treatment
Baseball Finger is not a serious injury and generally only requires a splint that holds the finger out straight. Occasionally surgery is required if the bone sustained serious damage.

The network of nerves that conducts signals from the spine to the shoulder, arm and hand is called the brachial plexus. The nerves to the arm, hand and fingers exit the spinal cord between the vertebrae of the neck and travel into the arm below the clavicle. While the nerves to the arm exit high in the neck, those leading to the hand and fingers exit lower in the neck just above the chest.

When these nerves are damaged, the hand may feel limp or paralyzed as a result of the loss in muscle control. Damage can result from a number of different types of injuries. When the nerves exiting high in the neck are affected, the condition is called Erb’s palsy and affects arm movement. And if both the lower and upper nerves are damaged, the condition is called Global palsy.

There are four primary types of brachial plexus injuries including: an avulsion, which is the most severe - as the nerve is completely torn from the spine; a rupture, which results in a torn nerve though no detachment; a neuroma, which is a damaged nerve that has tried to heal itself but scar tissue has grown around the injury - applying pressure to the injured nerve and disrupting signals to the muscles; and neuropraxia (stretch injury), which is among the most common type and results in a damaged nerve that is not torn.

Those at Risk
While a number of different types of injuries can result in a Brachial Plexus Injury, it is often seen in newborns experiencing a prolonged delivery and compression on the shoulders while passing through the birth canal or strong pulling on the neck during an assisted exit.

Diagnosis
The loss of movement or paralysis in the hand is a strong indicator of nerve damage. Following a patient history and description of how the injury occurred, an electromyogram (EMG) or nerve conduction studies (NCS) may be used to determine if nerve signals are present in the upper arm muscle.

Treatment
If the affected nerves show no signs of healing, or the condition is severe, nerve surgery followed by a period of splinting may be necessary for young children. These surgeries are most successful on children under the age of one.

A tendon transfer is often performed on older children and adults - followed by a period of casting and then splinting. Physical therapy is important in the recovery of any injury, but particularly when there is a period of casting as muscles quickly deteriorate they are not exercised. A patient-specific program is developed to restore strength and resume normal hand movement.

The damaged carpal bone most likely to result in Carpal Avascular Necrosis is the scaphoid bone. This may happen following a trauma and fracture to the scaphoid. Because the scaphoid bone has only one small artery that enters it near the base of the thumb, a fracture that tears the artery severs the blood supply. If not immediately diagnosed, this loss in blood supply can cause the bone to die - making union unlikely and surgery necessary.

Diagnosis
While the initial X-ray of these conditions may not always reveal an environment conducive to or presence of avascular necrosis, progressive pain and tenderness will eventually prompt another - as bone density and shape begin to change. In advanced stages, fragmentation and collapse occur and degenerative arthritis is the end result.

Treatment
Treatment of these Navicular Avascular Necrosis conditions depends on the condition of the bone, though early diagnosis increases the success of the treatments. In the early stages, intermittent immobilization may be recommended in order to allow reconstitution of normal bony structure. A removable cast may also be used in conjunction with range of motion exercises and targeted rehabilitation.

In advanced stages of these conditions, surgery is necessary.

Muscles generally insert into bones through tendons. Tendons have the ability to glide over bone and through tissue - and they are generally placed into two main categories, flexor and extensor. Flexor tendon injuries are classified into five zones: I through III include areas of the hand; IV consists of the wrist; and V involves the forearm.

Flexor tendon injuries have less impact on hand function, because there are several others to assist when one is damaged. But, there is only one extensor tendon responsible for the function of the second through the fifth finger, therefore an injury to this tendon has greater impact on hand function. These injuries are classified into eight zones - zones I through VI involve various areas of the hand, zone VII involves the wrist and multiple tendons, and zone VIII are injuries located in the distal forearm.

Tendon injuries are common and usually caused by accidents or high stress activity. In "open injuries," glass or knives are usually involved. And "closed injuries" are often caused by sports that overstress the tendons without disrupting the skin.

The complete detachment of a tendon results in the loss of its function, which can be permanent if not repaired. Patients are usually aware when a tendon becomes detached and will experience difficulty moving a finger and pain when trying to use the tendon.

Diagnosis
Understanding the activity that resulted in the tendon injury is important for a thorough assessment of the affected tendons and the extent of the damage. Once patient history is established the position of the injury (if a cut), the posture of the hand at rest, as well as passive and active movement are examined. In assessing passive movement, gentle pressure applied to each fingertip or the muscles in the forearm can identify a loss of tension or weakness of a joint. Also moving the wrist, which prompts finger movement, will indicate areas of weakness. In assessing active movement, patients are asked to use the tendon and affected joint while abnormalities are noted.

Treatment
Treatment for tendon injuries depends on the zone classification and extent of the injury - and can consist of splinting, the use of absorbable sutures, or hand surgery.

Flexor tendon lacerations should be repaired within 12 hours of the injury, though it is possible to splint with the fingers flexed for delayed repair - up to four weeks. Particular care is taken in the repair of these tendons because the synovial sheaths increase the risk of infection.

Extensor tendon lacerations require special attention during surgical repair, because they often retract into the hand when they are cut.

Rehabilitation is an important part of any treatment for tendon damage. Following a tendon repair there is a risk that the repair adheres to the surrounding tissues - preventing the tendon from gliding properly. In order to avoid this, protected mobilization is used in conjunction with a series of exercises specific to the injured area.

Recovery and return to work depends on the severity of the injury and type of work. It can range from six to 12 weeks.

Nerves are an integral part of body function - carrying messages from the brain to the rest of the body and back again. Something as simple as lifting a finger would not be possible if the message to do so was not carried by nerves from the brain to the hand. And serious injury could occur if the nerves sensing heat or pain were unable to convey a warning back to the brain. The three main nerves affecting hand, finger and thumb movement include the radial, median, and ulnar nerves.

The nerve fiber and its insulation are fragile and often damaged by excessive stretching, pressure or cutting - disrupting the conveyance of necessary information and proper muscle function.

Stretching or pressure related injuries may cause the fibers carrying the information to falter and prevent the nerve from working, without damaging its insulating cover. When nerve fibers are cut but the insulation remains undamaged, the end farthest from the brain dies - while a recovery process starts at the end closest to the brain. When both the nerve fiber and its insulation are cut, a recovery process does not begin automatically. In fact, a small mass may form at the end of the cut - forming a nerve scar, or neuroma. A neuroma can be painful and may even cause an electrical sensation when touched.

Those at Risk
Because there are many possible causes of nerve injury, there is no specific patient profile. Such injuries commonly involve falls, collisions, motor vehicle accidents, fractures, gunshot wounds, and cuts - or other forms of penetrating trauma.

Diagnosis
Determining which nerves have been affected in an injury involves an assessment that includes; the type of injury and affected area, patient history, the location of pain during hand movement, the loss of strength in the muscle supplied by the suspected nerve, and the location of numbness and loss of hand, finger or thumb function. Other signs of innervation deficiencies may be evident in the skin - as dry, shiny skin that does not wrinkle when immersed in water is the result of skin denervation. The severity of damage and grade of injury is determined with electrodiagnostic testing.

Treatment
Treatment will depend on the location and severity of the injury, as well as the type of activities and work in which patients are involved in daily life. It can range from supportive therapy to maintain range of motion and muscle tone, to a minimally invasive end-to-end suture closure, or surgical repair procedure appropriate for the type of damage the nerve and surrounding area sustained.

For simple nerve injuries, the nerve may be repaired immediately. If a wound is "dirty" or crushed and more complex - possibly involving a number of other injuries as well - nerve repair may take place following the repair of the other injured sites and later assessment of scar tissue development.

The end result and recovery depends on the age of the patient, the type of wound and nerve involved, as well as the location of the injury. But, targeted physical therapy always improves the chances of patients resuming normal function.

Also called "Skier's Thumb" and "Gamekeepers Thumb," injury to the Ulnar Collateral Ligament (UCL) of the thumb jeopardizes the strength of the ligament and its ability to secure the bones at the base of the thumb (metacarpophalangeal or MCP joint) and prevent the thumb from extending out too far away from the hand.

This type of injury is defined as an acute injury when it occurs as the result of stress placed on the ulnar collateral ligament from an extreme force (valgus force) - such as that experienced when the thumb is caught in a ski pole during a fall. In this situation the ligament undergoes an exaggerated stretch and often tears as a result.

Those at Risk
When a repetitive activity or sport eventually leads to the loosening of the ulnar collateral ligament over time, it is referred to as a chronic injury. Often times tennis players and baseball players will experience this.

Diagnosis
Those suffering from this type of injury generally experience some instability and difficulty griping things tightly. Though those with an acute tear of the UCL report pain and swelling directly over the torn ligament at the base of the thumb.

Both a physical examination and X-ray are done to confirm diagnosis and determine the extent of the injury. A valgus stress test is also performed in order to check the strength of the ligament and corresponding stability of the joint.

Treatment
Depending on the extent of the injury and other patient factors, either a thumb spica cast will be used to stabilize and encourage healing for approximately four to six weeks - followed by range of motion exercises to strengthen grip - or surgery is recommended

Surgery is considered in the case of a complete tear (rupture) of the ligament and evidence of significant instability. It is usually done several weeks following the injury and is considered an outpatient procedure. Patients generally see results within four weeks following the surgery and regain thumb strength. Occasionally the MCP joint continues to be unstable and causes pain during pinching or grasping activities. Since chronic instability and looseness of the thumb eventually results in the development of arthritis, other procedures may be considered - including grafting in new tissue to reconstruct the ligaments, or arthrodesis in order to fuse the joint.