Median Nerve/Root of Thumb
The median nerve, also known as the ‘root’ of the thumb, is an interrelated nerve with a function of primary importance in the movement of the thumb. It innervates all the muscles of the radial section of your hand and most of the tendons present in this part of your arm, namely the carpal tunnel, the median nerve, and several other muscles. The median nerve passes through a bony opening, known as the “carpal tunnel.” Due to its location, the median nerve is under high pressure and very vulnerable to trauma. Injury to the median nerve can result in severe pain, neurological dysfunction, permanent contracture of the thumb, and loss of dexterity.
One of three sets of median nerve branches, it begins in the upper chest and goes down through the shoulder and down the arms to the knuckle and thumb. Nerves that originate on the same side of your chest, tend to cross each other, and then branch off into their respective sides of your arms. This arrangement enables some nerves from different sets of muscles to innervate each other simultaneously, leading to widespread sensation of pain in your forearm. The median nerve passes through the carpal tunnel and has a wide distribution throughout the palm.
There are many potential causes of a broken finger tendon, including carpal tunnel syndrome, acute injuries to the wrist or elbow, and fractures of the bones surrounding the wrist. Common symptoms include tingling and weakness of the fingers; an inability to pinch, extend, or curl the palm; and clicking or popping sensations when the nerves are stimulated. Often, these symptoms are mistaken for the symptoms of other disorders, such as tennis elbow. It is not unusual, however, for patients with carpal tunnel syndrome or a fracture of the bones in the forearm to have symptoms consistent with median nerve paralysis. The diagnosis of interosseous fracture stumps can often be missed by an initial routine examination.
A typical interosseous fracture consists of a fragment of bone (the st Lump) embedded in a bony depression, called a postzygium. The location of the on Lump and the location of its fracture location, however, is not consistent across all patients. In addition, the nature of a typical interosseous fracture does not always correspond to the location of a particular nerve within the arm. Because nerves located outside the arm are not as easily accessible as those located in the arm, it is also not uncommon for misdiagnosed misalignments to cause major problems. For example, misaligned bones at the base of one’s thumb can cause excruciating pain, even though the nerve actually originates in the elbow. Such a condition, referred to as “thumb depression”, can lead to a more serious problem called “axillary malalignment” – a condition in which one half of a nerve is displaced to the palm, creating a wide arch of skin above the joint, rather than underneath it like it is supposed to be.
With the exception of rare, naturally occurring disorders, such as intervertebral disk disease, neurological disorders that involve the median nerve do not generally involve any underlying structural abnormality or mechanical deficiency in the arm. Typical causes of nerves of this type include arthritis, injuries caused by falls, or muscle imbalance. Muscle imbalance refers to a situation where one group of muscles (the muscles innervated) are overactive than normal, causing a patient to have symptoms similar to those of a chronic fatigue syndrome. If you suspect you have a median nerve entrapment, your doctor will need to take a complete medical history, perform a thorough physical exam, and order a nerve mobility test in order to rule out more serious conditions.
One serious condition that occasionally involves the median nerve is carpal tunnel syndrome. Symptoms include pain, swelling, and tingling in the hands, arms, and legs. Carpal tunnel syndrome is caused when the median nerve becomes trapped between the carpal bones of your hand. This can result from inflammation, which can be caused by tendinitis, a bulging disc, or other disorders.
Nerves of this type run through the upper limb and attach directly to the thumb, index finger, and middle and index finger of both hands. Certain movements, such as shaking hands, make the muscles of our hands contract. If the nerves are pinched, there can be pain, tingling, or a numbness in these parts of our hands. Other situations that can cause carpal tunnel syndrome include playing racquet sports, throwing, and piano playing.
Motor vehicle accidents frequently involve the nerves of the medial (inner) forearm. These nerves start in the medial epicondyle on the outer side of your hand. They pass through the brachial plexus, the bony prominence on the inside of your hand. The nerve roots eventually exit near the elbow joint. Any problems with the nerve can result in symptoms such as tingling and/or weakness in the affected area, although motor vehicle accident symptoms often occur on the medial forearm.