The hand nerves, which are responsible for the sensitive and motor supply of the hand, arise from you Nerve plexus (Plexus) of which there is one for each side of the body. This arm mesh is called in medical terminology Brachial plexus denotes and arises with the associated nerve fibers from the spinal cord segments of the 5th-7th centuries. Cervical spine and the 1st Thoracic vertebrae. (C5-Th1). Various individual nerves branch off from the nerve bundle, which in addition to the hand nerves also give off nerves to the neck, shoulder and arm.
The nerves for that poor get in the nerves for that in your course Hand supply above. These important structures include the three hand nerves:
- Median nerve
- Radial nerve
- Ulnar nerve
They pull from the nerve plexus on the neck through the arm, supply there next to the Musculature also sensitive the skin and pull with their terminal branches into the hand into it.
On the way of the three big ones Hand nerves to the hand, pull them out under a tough and tight band connective tissue through. This tape is called Flexor retinaculum muscle designated. It limited just before that wrist up one room. This as Carpal tunnel (Canalis carpalis) designated space is a passage for the Tendons the hand muscles, the tendon of the thumb and for the Median nerve.
If hand nerves are damaged in various ways, they may develop in the affected hand Pain sensations as well as sensory disturbances. The manifestations of pain in injuries to the hand can express themselves in different ways. Is the pain light or severe, acute or has it been lasting for a long time? How exactly does the pain feel, pulling, burning, stabbing, knocking? Is the pain limited to one area of the hand, e.g. a finger, or does the pain radiate into the forearm or shoulder? Do I feel the pain permanently or only when I press it or when I move my wrist or individual fingers?
The Localization and expression of the pain can provide information about the location and form of the injury to a nerve. Pain or loss of sensitivity suggest damage to one sensitive part of a hand nerve close. If movement in the wrist or individual fingers is impaired, a motor nerve branch damaged.
Since the three hand nerves, the radial nerve, the median nerve and the ulnar nerve, each supply certain parts of the hand sensitively and motorically, it is possible to roughly assign a pain that can be precisely localized to one of the nerves.
However, pain in the hand can also originate from other structures, e.g. pain is common when the wrist is overloaded.
Injuries to the nerves of the hand
Injuries to the hand nerves can be described above Pain cause. The localization of the injury doesn't have to be strictly limited to the hand, either Injuries to the upper and lower arm, shoulder and elbow can manifest as pain in the hand. Nerves can be damaged or severed by external force, e.g. cuts, bruises, breaks or burns. Damage to the surrounding tissue can lead to Entrapment or crushing come from hand nerves at constrictions in the nerve courses that cause symptoms similar to direct nerve injury.
Pain can also be caused by the irritation of a nerve, e.g. due to overload or inflammation.
Often describe patients with acute Hand injuries typical wound or injury pain. This does not necessarily have to indicate an injury to a nerve. If a sensitive nerve has been damaged, this often only becomes apparent after the acute wound pain has subsided after hours or days, depending on the size of the injury. Typical symptoms are included Depressionpersistent pain tingle in the fingers or deafness.
After seeing the doctor again, it is important to make a diagnosis of the type of nerve injury. If the nerve is only damaged or irritated, regeneration is possible without surgery. This is not possible if a nerve cord is severed. Surgical measures are necessary to ensure that the nerve will grow together again. The symptoms of the nerve injury can persist for a longer period of time, despite the operation, since the growing together of the nerve endings is a very tedious process.
The Median nerve arises from the nerve plexus from the so-called Median fork. After he got the upper arm has happened, this hand nerve pulls towards the flexor side of the arm thumb. It runs under the Retinaculum musculorum flexorum in the carpal tunnel between the deep and superficial tendons of the flexor muscles up to Palm. In the palm of the hand it finally branches into his motor and sensitive Branches up.
The motor nerve fibers supply the muscles on the thumb (thenar muscles). They do that there Abduction, Flexion and the juxtaposition of the thumb to the little finger. In addition, the innervates Median nerve the deep flexors of the index finger and middle finger. The inner surface of the hand on the side of the thumb, the thumb the hand nerve takes care of itself, as well as the index and middle fingers. This is where the forwarding of the sensitivity takes place like contact and Tactile sensation. The nerve at the tips of the index and middle finger has its own and sole sensitive supply area, known as the autonomy area.
Carpal tunnel syndrome
Due to various causes it can lead to a chronic pressure increase in the Carpal tunnel come. To this root cause Space-occupying processes, fractures, dislocations on the carpal bones, inflammatory processes on the tendons, but also edema caused by a pregnancy belong. The pulling one Median nerve be compressed by the existing narrowness and restricted in its function. In the following it comes to Loss of sensitivity especially in the Fingertips. Remains that Pressure rise persist longer in the carpal tunnel, additional motor failures occur as the disease progresses. One speaks of a positive Bottle signbecause the patient is no longer able to completely encircle a bottle with his thumb.
Upper median lesion
Traumatic damage such as fractures and dislocation can also occur in the elbow area. Due to the close proximity to the hand nerve, this can also be injured quickly.
The clinical picture then shows the typical swearing hand for such an injury. If the person concerned tries to close his restricted fist, the thumb, index and middle fingers are not bent properly. The muscles are no longer innervated by the hand nerves and can no longer carry out their actual movement.
In addition, other symptoms such as numbness and muscle wasting in the area of the thumb may occur.
The Radial nerve is made up of the rear Nerve roots of the arm mesh together and formed their direct continuation. He pulls forward on the back of the arm along the humerus. At the level of the elbow he steps forward again and finally runs on the back of the forearm to the side of the thumb hand. When you reach your thumb, it branches off Radial nerve into its sensitive terminal branches. On the hand, he mainly cares for the area of the thumb and sometimes the back of the hand sensitive. During its course, it transfers its motor branches on the upper and lower arm to the muscles there. This hand nerve innervates the extensor muscles of the upper arm and the extensor muscles of the thumb.
In the case of fractures or other injuries in the area of the upper arm bone (humerus), the radial nerve is particularly at risk due to its close proximity to the bone. If he is injured, complaints such as sensory disorders and motor failures occur. The motor impairment manifests itself as a so-called hand drop. When intact, the hand nerve is responsible for the extensor muscles. If he is now restricted in his function, he can no longer raise his hand and the hand falls limply as a result.
Read more on the subject at: Drop hand
After the Ulnar nerve has emerged from the network of arms, it pulls in the side of the facing towards the body Upper arm along. It loops around the elbow bone and finally pulls on the side facing the little finger forearm along until wrist.
Shortly before the Retinaculum musculorum flexorum The hand nerve splits into a superficial and a deep branch. Already during its course through the forearm innervated he muscles lying there. On the hand he is responsible for the motor innervation of some Muscles responsible for the ball of the thumb, as well as for the muscles of the little finger ball. It also largely supplies the muscles of the metacarpus. The Innervation these muscles enables the spreading and closing of the fingers. The hand nerve supplies the sensitive ones skin over the little finger and half of the adjacent ring finger.
Ulnar channel syndrome
In the area of the Elbow the nerve runs through a gut palpable groove, the Sulcus nervi ulnaris. The hand nerve runs here directly under the skin and stands in the tight Contact with the one below bone. By easy Bump can quickly due to the superficial location of the nerve Paresthesia to be triggered. Most people know these symptoms as Funny bones.
If the hand nerve is damaged by a fracture or dislocation in the area of the Damaged elbow joint, the symptoms of a Claw hand on. The ability of the hand muscles is lost in the process finger to spread as they are from that Ulnar nerve can no longer be properly innervated. The fingers of the affected hand remain in one bent position stand and are therefore referred to as clawed hand. In addition to the motor disorders there are also sensitive failures. These particularly often affect the skin over the little finger and ring finger.
Therapy for nerve injuries
The Restoration one injured Hand nerve is often a complicated operation, as it involves very small and fine structures that must first be found. Since nerves often run through the poor and through the hand of Veins and Arteries accompanied this microsurgical procedure must be carried out with particular care so that additional structures are not injured.
By means of a Nerve suture with a hair the size of a hair thread the respective ends of the hand nerve are back together connected. For weeks after the procedure, the patient will feel electrifying pain and the restoration of the function of the muscles innervated by the nerve will take up to several months. Often the patient still feels Sensory disturbances and Numbness. For a successful therapy is adherence to the treated by the doctor prescribed immobilization. This is followed by an increasing Exercise therapy by Physiotherapists or occupational therapists.
If one is suspected Nerve injury, especially with complete Severing of the nerve, the person affected should immediately go to the nearest one hospital to be brought. A timely surgery is very important for a successful restoration of nerve function important.
Otherwise, benign lumps may form. They are called Neuromas denotes and develop from the hurt Nerve tissue. They are difficult to remove without the nerve possibly continue to damage. They can also lead to unpleasant phantom pain. The patient then feels an electrifying one pain and a tingle.