Baseball Finger is often the result of damage caused to the tendons that assist in straightening out the finger - usually when the fingertip is forcefully jammed or bent downward. Also known as Mallet Finger, symptoms may include swelling and tenderness around the fingertip.

Risk Factors
Athletes involved in not only baseball, but football and basketball as well, are at risk for such an injury as a result of the force involved in these sports and the rapid motion and awkward positions in which their hands and fingers are often placed.

Diagnosis and Treatment
Understanding the action resulting in the injury often helps determine diagnosis. In confirming Baseball Finger, 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.

Not considered a serious injury, Baseball Finger generally only requires a splint that maintains the finger in a straight position. Occasionally surgery is required, if the bone sustained serious damage.

Brachial Plexus is most commonly seen in newborns experiencing shoulder compression while passing through the birth canal during a lengthy delivery. Forceful pulling on their neck during an assisted exit may also result in a Brachial Plexus injury. Brachial plexus injuries most commonly seen in adults are generally the result of a traumatic injury such as that inflicted in a motorcycle or other high-speed motor vehicle accident. A fall from a great height may also result in this type of injury.

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.

The four primary types of brachial plexus injuries include: an avulsion, the most severe form of brachial plexus, because the nerve is completely torn from the spine; a rupture, which is a torn nerve with no detachment; a neuroma, which is a damaged nerve that has tried to heal itself but developed scar tissue around the injury - causing increased pressure to the injured nerve and disrupting signals to the muscles; and neuropraxia, which is a stretch injury and among the most common type of brachial plexus injury, resulting in a damaged nerve that is not torn.

Risk Factors
Brachial Plexus is most commonly seen in newborns experiencing shoulder compression while passing through the birth canal during a lengthy delivery. Forceful pulling on their neck during an assisted exit may also result in a Brachial Plexus injury. Occasionally, other types of injuries causing restriction or compression to the vulnerable areas may result in this type of injury as well.

Diagnosis and Treatment
A hand that experiences loss of muscle control and becomes limp or paralyzed shows strong indication of nerve damage. Following a thorough patient examination, history and discussion of how the injury occurred, an electromyogram (EMG) or nerve conduction study (NCS) may be used to determine if nerve signals are present in the upper arm muscle.

While conservative treatment may be initially indicated, nerve surgery may be necessary if the affected nerves show no signs of healing followed by a period of splinting, or the condition is severe. These types of surgeries are most successful on children who are less than one year old.

For older children and adults, a tendon transfer is often performed 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 because muscles that are immobilized quickly deteriorate. A specific rehabilitation program helps restore strength and re-establish normal hand movement.

Carpal Avascular Necrosis is the loss of necessary blood supply to a bone and most often results from the improper healing of a damaged carpal bone known as the scaphoid - following a trauma and subsequent fracture. This is most commonly associated with damage to the scaphoid bone, because this particular carpal bone has only one small blood-supplying artery located near the base of the thumb. A fracture that tears the artery severs the blood supply. This loss in blood supply will cause the bone to die and make union and bone healing unlikely, if undiagnosed.

Risk Factors
Patients sustaining a severe distal radius or wrist fracture affecting the scaphoid bone are at risk for carpal avascular necrosis. Though one of the strongest carpal bones and most difficult to break, scaphoid fractures account for nearly 60 percent of all wrist fractures. Because it is so strong, the type of force required to damage the scaphoid bone is that which is generally found in sports or severe accidents. An injury to the scaphoid occurs when the wrist joint of an outstretched hand hyperextends.

Men are much more likely to fracture this bone than women, because of the types of sports and activities in which they are involved - as well as the increased weight sustained by the wrist joint during a push or fall.

Diagnosis and Treatment
The presence of avascular necrosis may not be initially evident upon early X-ray, though the severity of the fracture and progressive pain and tenderness as bone density and shape begin to change will prompt further testing.

In advanced stages, fragmentation and collapse occur and degenerative arthritis is the end result.

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.

A tendon is a band of tough fibrous tissue that connects muscle to bone or other muscle. It is capable of withstanding a great deal of tension. Working together, tendons and muscles exert only a pulling force.

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 by zones: zones I through III include areas of the hand; IV consists of the wrist; and V involves the forearm.

While flexor tendon injuries have less impact on hand function, because there are several others to assist when one is damaged, there is only one extensor tendon responsible for the function of the second through the fifth finger. Therefore, an injury to this tendon has a greater impact on hand function. Extensor tendon 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.

There are various degrees of injury as well. When glass or knives are involved the injury is called an "open injury." And "closed injuries" are often caused by sports that overstress the tendons but do not disrupt 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.

Risk Factors
Accidents or forceful activity can cause injury to a tendon, which is why tendon injuries are common. They can happen to any one at any age.

Diagnosis and Treatment
The manner in which the injury was incurred, the affected area and the subsequent symptoms play a large role in the diagnosis of a tendon injury. Following a thorough review of patient history a physical examination of the hand is performed, which entails examining the posture of the hand at rest, as well as in passive and active motion.

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. Moving the wrist, which prompts finger movement, will also indicate areas of weakness. In assessing active movement, patients are asked to use the tendon and affected joint while abnormal observations are recorded.

The best type of treatment for tendon injuries depends on the zone classification and extent of the injury. Conservative treatment is almost always the initial course of action and may consist of splinting, and the use of absorbable sutures if a cut is involved. More serious injuries may require hand surgery.

When lacerations accompany flexor tendon injuries repair should take place within 12 hours of the injury, though it is possible to splint with the fingers flexed for delayed repair - up to four weeks. Since the synovial sheaths increase the risk of infection, particular care is taken in the repair of these tendons.

And extensor tendon lacerations are delicately addressed during surgical repair, because they can 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 can range from six to 12 weeks, depending on the severity of the injury and type of work the patient performs.

Part of an intricate network responsible for carrying messages from the brain to the rest of the body, nerves are an essential part of body function. From lifting a finger, to moving a hand off a hot surface, nerves make it possible to react when the brain indicates.

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.

It is possible for nerve fibers to be negatively impacted by a stressful activity or injury, causing an interruption in its transmission of messages from the brain but leaving its insulating cover undamaged. When nerve fibers are cut but the insulation remains undamaged, the end farthest from the brain dies, which prompts a recovery process to begin at the end closest to the brain.

But, 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.

Risk Factors
Nerve injuries can affect anyone at any age, because they comprise a delicate network that runs throughout our body and can be disrupted by any number of activities or accidents. Though, a large number of nerve injuries commonly involve falls, collisions, motor vehicle accidents, fractures, gunshot wounds, cuts and other forms of penetrating trauma.

Diagnosis and Treatment
There are a number of ways to determine if nerve damage has occurred and to what extent it has been affected. Following a thorough review of the patient's medical history and incident causing the injury, there is a full assessment of the injury and affected area, as well as 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. Dry, shiny skin that does not wrinkle when immersed in water is the result of skin denervation. Electrodiagnostic testing can determine the severity of damage and grade of injury.

The treatment option is determined based on the location of the damage and severity of the injury, as well as the type of daily activities and work to which patients must return. Conservative treatment may be all that is indicated and may consist of supportive therapy in order to maintain range of motion and muscle tone. A minimally invasive end-to-end suture closure, or surgical repair may be indicated.

Simple nerve injuries may be repaired immediately, while a more complex wound - possibly involving multiple injuries - may need to be postponed until other injuries are addressed and potential development of scar tissue assessed.

Ultimately, 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. Though, targeted physical therapy greatly improves the chances of resuming normal function.

The proximal interphalangeal (PIP) joint is the finger joint closest to the knuckle, or metacarpophalangeal (MCP) joint. With the help of ligaments, the PIP joint is one of two interphalangeal (IP) joints responsible for connecting the three phalanges of the finger.

Hands are vulnerable to injury because of the role they play in sports and everyday activity. Injury to the PIP joint is one of the most common injuries the hand sustains and can occur as a sprain or a complete tear of the ligament - resultant of an activity that causes the joint to hyperextend - as well as a dislocation.

A sprain represents a ligament that has been stretched and partially torn. A complete tear represents a ligament that has ruptured or torn completely away from its attachment to the middle phalanx. Occasionally, there is also a small bone fragment that pulls away as well. This is called an avulsion. A dislocation occurs when the middle phalanx is pushed behind the proximal phalanx.

Sometimes the pain from a sprain is subtle, which can delay diagnosis and cause more severe problems. Though symptoms associated with a ligament tear may cause great discomfort. There may be pain and swelling. And a complete dislocation will cause an obvious deformity.

Risk Factors
PIP injuries are common injuries in throwing and catching sports, where the hands are frequently vulnerable to excessive force. They may also occur in falling or automobile accidents.

Diagnosis and Treatment
Description of the manner in which the injury occurred and a physical examination are generally all that is necessary in diagnosing a PIP injury. An x-ray will confirm physical findings. Treatment will vary depending on the severity of the injury.

Conservative, or nonsurgical, treatment may consist of short-term splinting and rehabilitative exercises in order to avoid stiffness within this sensitive joint. Steps are also taken to reduce swelling, which can cause permanent stiffness. Brief periods of immobilization, early range of motion exercises and day-to-day movement are key to restoring full function to this particular joint.

More severe injuries may require surgery to repair the damage and perform realignment. If PIP injuries are not addressed properly an environment of instability will quickly deteriorate the joint environment.

In severe cases of instability and joint deterioration, PIP joint replacement may be required.

An Ulnar Collateral Ligament of the Thumb (UCL) Injury, which is also referred to as "Skier's Thumb" and "Gamekeeper's Thumb," weakens the UCL and its ability to secure the bones at the base of the thumb (metacarpophalangeal or MCP joint). As a result, the thumb is unable to extend out very far from the hand.

When it is defined as an acute injury, it more accurately depicts the type of injury for which it acquired the name "Skier's thumb." This type of injury is the result of stress placed on the ulnar collateral ligament from an extreme force (valgus force) - such as that which may be 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 suffering from an acute UCL injury will experience pain and swelling over the area of the damaged ligament at the base of the thumb. There is difficulty grasping or holding objects firmly and some instability.

The name "Gamekeeper's Thumb" was acquired by the more chronic pattern, which leads to loosening of the ligament over time. Named after early European gamekeeper's, who killed their game by grasping the animal's head between their thumb and index finger to break its neck. This repeated stress results in loosening over time and more chronic patterns of the injury. Today, tennis players and baseball players are more likely to experience this type of UCL injury.

Risk Factors
Those involved in activities or sports that place the thumb in a vulnerable position or those who subject it to repeated stress are at risk for this type of injury. It is often seen in athletes.

Diagnosis and Treatment
A thorough review of the patient's medical history and assessment of the manner in which the injury was incurred will help determine diagnosis. The symptoms experienced and the location of the pain also play a part in diagnosis. Both a physical examination and X-ray are done to confirm initial assessments 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 depends on the severity of the injury, when the injury occurred and other patient factors. For a incomplete tear a thumb spica cast may be used for approximately four to six weeks in order to stabilize and encourage healing. This may be followed by range of motion exercises to improve grip strength.

In more severe cases involving a complete tear or rupture of the ligament and significant instability, surgery is considered - and generally done as an outpatient procedure several weeks following the injury. Patients usually see results within four weeks following the surgery, regaining thumb strength and function. Occasionally the MCP joint will remain unstable and causes pain during pinching or grasping activities. In order to prevent the eventual development of arthritis, which is caused by this type of chronic instability and looseness of the thumb, other procedures may be considered. Such procedures may include grafting in new tissue in order to reconstruct the ligaments, or arthrodesis in order to fuse the joint.