Паралич лучевой нерва: причины, диагностика и лечение.

Peroneal nerve paralysis is a paralysis on common fibular nerve that affects patient’s ability to lift the foot at the ankle. The condition was named after Friedrich Albert von Zenker. Peroneal nerve paralysis usually leads to neuromuscular disorder, peroneal nerve injury, or foot drop which can be symptoms of more serious disorders such as nerve compression. The origin of peroneal nerve palsy has been reported to be associated with musculoskeletal injury or isolated nerve traction and compression. Also it has been reported to be mass lesions and metabolic syndromes. Peroneal nerve is most commonly interrupted at the knee and possibly at the joint of hip and ankle. Most studies reported that about 30% of peroneal nerve palsy is followed from knee dislocations. Peroneal nerve injury occurs when the knee is exposed to various stress. It occurs when the posterolateral corner structure of knee is injured. Relatively tethered location around fibular head, tenuous vascular supply and epineural connective tissues are possible factors that cause damage on the common peroneal nerve. Treatment options for nerve palsy include both operative and non operative techniques. Initial treatment includes physical therapy and ankle foot orthosis. Physical therapy mainly focuses on preventing deformation by stretching the posterior ankle capsule. A special brace or splint worn inside the shoe (called an Ankle Foot Orthosis) holds the foot in the best position for walking. Orthosis stretches posterior ankle structures. Physical therapy can help patients to learn how to walk with a foot drop.

Electromyography is used to observe peroneal nerve palsy within one month of injuries. And if it is partial peroneal nerve palsy, patients have higher chance to recover fully from the palsy. More than 70 to 80 percent of patients with partial paralysis recovered completely, but those with complete paralysis have chances less than 30 percent to recover completely. If the symptom does not get any better in few months, surgery is required to decompress the nerve compression.

Nerve conduction velocity is an important aspect of nerve conduction studies. It is the speed at which an electrochemical impulse propagates down a neural pathway. Conduction velocities are affected by a wide array of factors, including age, sex, and various medical conditions. Studies allow for better diagnoses of various neuropathies, especially demyelinating conditions as these conditions result in reduced or non existent conduction velocities. To perform nerve conduction velocity, surface electrodes are placed onto the skin over nerves at various locations. Each patch sends electrical impulses which stimulate the nerve. Resulting electrical activity of nerve is recorded by the other electrodes. The distance between electrodes and the time it takes for electrical impulses to travel between electrodes are used to determine the velocity of the nerve signals.

An MRI (magnetic resonance imaging) scan is an imaging test that uses powerful magnets and radio waves to create pictures of the body. It does not use radiation. Single MRI images are called slices. The images can be stored on a computer or printed on film. One exam produces dozens or sometimes hundreds of images. To locate nerve palsy, MRI is used by physicians to detect the position and location of damaged peroneal nerve.

Precise knowledge about the length and exact localization of a damaged nerve segment is essential for surgical intervention. On one hand, certain preoperative information about the overall state of an injured nerve (state of the neural and perineural tissue) is important because exploratory inspection of a nerve itself may lead to additional inadvertent damage. If, on the other hand, the surgeon, during genicular ligament reconstruction, inspects a nerve at the site of most probable injury only (limited neurolysis), he or she may sometimes by chance expose an unaffected section of a nerve. Because of the mechanism of nerve injury during traction, however, a more proximal or distal segment of the nerve may be severely damaged. A limited nerve inspection without preoperative knowledge about the site of nerve injury may thus give the false impression of an unimpaired nerve and wrongly lead to conservative treatment of the nerve lesion. If no neurologic improvement is shown after 2–3 months from injuries, then operative decompression is indicated. Surgical operations such as grafting and tendon transfer are necessarily required.

Many different conditions can be treated by tendon transfer surgery. Tendon transfer surgery is necessary when a certain muscle function is lost because of a nerve injury. If a nerve is injured and cannot be repaired, then the nerve no longer sends signals to certain muscles. Those muscles are paralyzed and their muscle function is lost. Tendon transfer surgery can be used to attempt to replace that function. Common nerve injuries that are treated with tendon transfer surgery are spinal cord, radial nerve, ulnar nerve, or median nerve injury. Tendon transfers have higher chance to treat nerve palsy, and such transfers include posterior, anterior, and anteroposterior tibial tendon transfer. Peroneal nerve and its nerve branches need to be fixed from adherence to proximal fibula, which proximal fibula is about 3~5 cm.

Grafting is a surgical procedure to move tissue from one site to another on the body, or from another person, without bringing its own blood supply with it. Instead, a new blood supply grows in after it is placed. A similar technique where tissue is transferred with the blood supply intact is called a flap. In some instances a grafting can be an artificially manufactured device. Examples of this are a tube to carry blood flow across a defect or from an artery to a vein for use in hemodialysis.

Arthroplasty on knee has been broadly used to treat knee and musculoskeletal joint dislocation. It is an elective procedure that is done to relieve pain and restore function to the joint after damage by arthritis or some other type of trauma. However, there has been series of reports arthroplasty worsens condition of peroneal nerve, causing paralysis. Other forms of arthroplasty include resection (al) arthroplasty, resurfacing arthroplasty, mold arthroplasty, cup arthroplasty, silicone replacement arthroplasty, etc.

Friedrich Albert von Zenker (1825–1898) was a German pathologist and physician, celebrated for his discovery of trichinosis. He was born in Dresden and was educated in Leipzig and Heidelberg. He worked in the city hospital of Dresden in 1851 and became a professor of pathological anatomy and general pathology in the surgico medical academy of the city. In 1862 he became a professor of pathological anatomy and pharmacology at Erlangen. Three years later he assumed with Ziemssen the editorship of the Deutsches Archiv für klinische Medizin. In 1895 he retired from active service. His important discovery of the danger of trichine dates from 1860. In that year he published "Über die Trichinenkrankheit des Menschen" ("On the trichine illness of humans", in volume XVIII of Virchow's Archiv). Zenker also found Zenker's degeneration and Zenker's diverticulum.