Trauma of a peripheral nerve.
Three periods at traumas. If we consider the problem, for what the person has a brain and nervous system, what is their functions and tasks, we shall come to a conclusion, that their role consists in a maintenance of a survival and safety of organism in the most effective way. For this purpose the nervous system is divided on vegetative, ensuring homeostasis - constancy of internal environment (digestion, circulation, temperature etc.) and central (CNS), which together with peripheral one ensures interaction with external environment. A vegetative nervous system works autonomously, but under the control of a CNS (the intellectual activity of the person also is one of a constituent of CNS work, directed in the issue on maintenance of a "comfortabl " safe existence). The CNS role consists in the analysing of external acting, discerning of new information and, proceeding from being available priorities, making choice of the most frugally and fast reaction..
One of aspects of safe existence is the process of oneself restoration of an organizm at traumas. Let's consider, how this process proceeds.
At any traumas the organizm condition can conditionally be divided on three periods: period of a trauma and its healing; period of rehabilitation of consequences; and subsequent stationary condition.
At the first stage the leading role vegetative nervous system plays. The rests of a died tissues are removed, the process of regeneration is activated, the infringed system of blood circulation is restored, again sprout the nerve-endings. What it is impossible to restore, is replaced with cicatrix. At last homeostasis is restored, but with the certain functional infringements. CNS enters in action. Now it must determine, what disturbances these infringements introduce to the information processing and elaborating of commands, in reflex activity and to correct the accumulated reflexes with taking the disturbances into account.
The reflexes that are moving stereotypes, are changed so that to realize a principle of maximum speed and economy of reflex reaction in new conditions. (The similar tasks stay and at vegetative nervous system. For example, if the kidney or lung are removed, the reorganization should occurs of its work to save a constancy of an internal homeostasis in the conditions of an increased load on the survive bodies.)
In a reality the first and second periods are partially crossed.
Let's consider two examples, on which we shall try to show, what problems an organizm must solves at infringements of work of the muscle-skeleton motor system irrespective of whether it is due to usual traumas, or due to defeats of nervous system.

For example, the person has broken the shoulder bone. The fracture is "accurate" - simple, there was not resulted in significant traumatizing of soft tissues, nerves. Plaster have been bandaged. When the bone has accreted - plaster has removed. The first period was terminated. After removal of plaster it was found out, that contractures of ulnar- and shoulder-joints have appeared. The hand is not unbended completely and extent of movements in a sholder-joint is limited. The second period - restoration of mobility of a hand begins. In 10-20 days this period comes to the end - or complete victory and restoration of movements in complete extent, or with some restrictions. Further - a period of a stationary condition. When analyzing this example it is possible to make the important conclusion. Although the trauma has not resulted in a pathology of muscles and copulas, nevertheless, the extent of movements have been limited. It is connected to that during the first period CNS have been generated new reflex conditions of a moving system, which maximum promoting to healing on the first stage. The second period is called to transform back the reflex activity of CNS for restoration of moving stereotypes. In instruction to this process has passed successfully, a hand is bended and unbended with gradually increasing of the extent of movements, speed and force (and it it is enough painful). For increasing of efficiency of the procedures and reduction of a painfullness they make massage. It is clear, that if an angle of a hand bending is not increased, then how much as we trained it, it will be not possible to restore movement completely. Or, if we were limited only to massage, competent, long, intensive, the success too will be unachievable. If we rendered adequate effect (forced and aidless bending of a hand), but till in 5-10 minutes per day, or one time per week, the result also will be negative.

I.e., the acting should be adequate (movement of a hand and own work of muscles of a hand), have necessary intensity and duration.).

The second example is model one over CNS traumas.
Let's assume, that the person have a cut trauma of a leg, at which it was found, that sciatic nerve is intersected completely. The surgeons have sewed a nerve, the wound have cicatrized.
Actually, the first period is ended on this. But intersected nerve is divided into two parts. First part goes from a backbone to a place of a cut. Second part spread from a place of a cut to area of innervation in tissues of a leg. At once after a trauma the second part perishes. On a place of degenerated part of a nerve still have products of decomposition, which are the guides for germination of separate axones from the first part of a nerve. The nerve themselves is a bunch of axones - various types of nervous fibres - sensitive (sensors), motor, gamma-motoneurons.

It is impossible to imagine, with what chaos of signals the brain collides. And the problem of what complexity stands before it. The problem is similar to a children toy - puzzles.
There is an image and a heap of the diverse form fishes, from which it is necessary to combine this image. And the more heap, the fineer elements, the more difficult problem is. But in this case we have not tens fishes-axones, but tens thousands.

The trauma of a nerve can be compared to breakage of multiple telephone cable. The operator has found breakage, has connected wires, but the telephones are silent. Still it is necessary re-switch on a station the entering wires from this cable to find pairs of wires from the users, and then to connect them to the necessary channels.

The nerve is a "cable" with assemblage of wires, that are divided on cable assembles by the separate braids. About 25 % from general section of a nerve take separate "wires" proper, axones, with a diameter of 5-20 micrometer. It means, that nerve with a diameter about 5 mm contained some tens thousand axones from neuron of various types and purposes.
And now they are intertangled, the nervous pulses get through absolutely not there, where they got through before a trauma. And for restoration of movement the brain (CNS) should unequivocally identify them and re-switch both on a way to a brain, and in analytical departments of a brain.

Let's try to explain, what problem solves the brain, when marshals an accordance of restored axones and how the rehabilitation procedures help him in this.

Each have been ridden by a bicycle, even on three-wheel. Let's imagin yourselves, that when driving driving you operate through springs or rubber tapes that are bent to a handlebar. It is extremely difficultly to guess, with what effort it is necessary to pull a tape, for the handlebar turned on a necessary angle. It is necessary to correct stretching alternately for tapes. The eyes are the gauge recording a mistake, and the brain, according to size and a sign of the mistake, gives to hands the instruction to pull or to weaken a tape, and as much. Something similar occurs at work of muscles.

The muscles have a feature. They can not push, and their function they execute by traction. In our example with a bicycle one rubber tape being stretched executes a role of a traction muscle. The second tape at this time should weaken the tension (muscle relaxs and is extended), but equally so far forth that the handlebar do not jump the necessary angle or do not stopped earlier, than it is necessary. When we ride on a bicycle, the eyes trace of a handlebar turning and give an instruction to hands, what of tapes to weaken, and what to haul, that the angle of turning of a handlebar was just what we want.

When the limb fulfill a movement, the the same process occurs. In the simplified kind the bones of limbs are levers, that are connected with hinges - joints. A minimum one pair of muscles - antagonist is attached by sinews to the ends of bones. One muscle, being constricted, increases an angle between bones (extensor), other - reduces (flexor). In a reality the set of muscles is greater, because in the majority of joints there is an opportunity of three-dimensional movement. The muscles consist from muscle fibres incorporated in moving units. Each moving unit innervated by one motoneuron, from which the nerve-endings offgo to each fibre of moving unit. The more frequency of nervous pulses, that coming through motoneuron - the more a muscle fibre is constricted.

In instruction to the brain could trace, what stress it is necessary to set up in each of muscles - antagonist, muscles, sinews, joint pouch are supplied with gauges - proprioceptors, sinew and joint receptor. They send the information coded by frequency of pulses, about a degree of lengthening or constriction of muscle fibres, speed of constriction and degree of a tension, size of a angle in a joint. The set of the signals from these receptors allows us to realize the our body in space, mentally to imagine the perpetrated movement.

Proprioceptors are special muscle fibres attached parallel muscle fibres by one end to a sinew, and by the second - to muscle fibres. On proprioceptors the nervous-endings are attached. When the muscle is constricted - proprioceptor also is constricted. The muscle is outstretched - and proprioceptor is outstretched too and the frequency of pulses generated from the nervous ending, that is fixed on it, accordingly varies.

Physiological peculiarity of receptors (neurones) is that the frequency of nervous pulses behind small exception does not exceed 100 hertz (100 pulses per one second). If we have tried to code with this frequency all range of a muscle constriction or its speed, we would receive the very rough tool, because all range of movement would be possible to break only on hundred parts. But the nature has bypassed this difficulty. To proprioceptors motoneurons are approached through which the instruction is transmitted to outstretched proprioceptor to be constricted or to constricted one - to be outstretched a little. Thus dynamic range of a proprioceptor is extended.

Summarizing aforementioned, such picture appears. As a minimum a moving unit is "served" by one motoneuron and two sensor neurones from proprioceptor, transmitting the information about lengthening of muscle fibres and speed of change of their length, by neuron from sinew receptor, giving the information on a degree of a tension, by pair of motoneurons that fine-adjuste of proprioceptor under lengthening and speed of lengthening of muscle fibres, and by joint's receptors of two types, frequency of one of them is increased, and other one decreases at reduction of an angle in a joint. Axones of all these neurons enter into structure of a nerve, that innervated a muscle of a limb.
The similar set accompanies a moving unit of a muscle-antagonist. The process of movement is realized as follows. A brain has the task - to bend a limb, i.e., to turn a bone in a joint on some angle. The signal is sent through motoneuron to moving unit of a muscle-flexor to be reduced to necessary length, and the signals to moving unit of a muscle-extensor are switched off and it relaxs. (As before performing of movement the angle between bones was fixed, this means that to moving units of this pair muscles-antagonists the nervous pulses have went, ensuring a necessary degree of a stress of muscles fibres.)
From proprioceptors sensor endings and from sinew receptors an information feeds in CNS, how the instruction on change of an angle in a joint is executed. This information is compared to a reference picture of a required final condition of a limb, being available in a memory, and if necessary adjusting instruction are sent. This is just a loop of sensor correction. Certainly, the described model is rather schematical, but from it at least it is possible to understand, that if these axones are even partially intertangle, the normal work of a limb is impossible.

Let's return to our operator. If his device worked only in that case, when all 100 wires are connected correctly, and the necessary combination has appeared the last, he should perform 100! (hundred - factorial) rearrangements, that approximately are equal to 10⁷⁷ attempts. For example, on being available concepts and facts the age of the universe no more than 5 billions years. It is 5*10⁹ years. Doing one attempt per one second the operator would be able while time of the Earth existence to reassemble only 2*10¹⁷ combinations. By such way it is an impossible task. But the operator acts simplier. Firstly, the telephone network is arranged thus (and the operator knows about it), that two wires going to the telephone are closed. Therefore with the help of the tester he enough fast determines pairs of wires going to the telephone. After that he needs to ring round the users, to specify the answered number and to connect this pair to necessary number. If all users are on a place, all procedure will take 1-2 hours.

In our example, as we already have found out, not all axones get through on its places. It means, there is a problem before a brain, which was decided by the operator. What is the algorithm of the decision we do not know, but we can assume, that it is exists and rather effective, because eventually it is came off to restore movement of a limb in a whole, though the task that stands before a brain is immeasurably more difficult, and it solves it in rather short time. As it is possible to understand, all that CNS possesses are impulses that are sent through motoneurons (analogue of the operator's tester), expectable response on them from the sensors endings (parties) and images of moving stereotypes stored in a memory.

Let's assume, that such task should be solved by us. We repeat, how it occurs actually, we do not know. But the base presupposition consists that a brain, CNS can determine new ways for nervous pulses and their place in the analytical programs of processing of the information for restoration of the genetically given movements of injured limb. A question only is, whether it is possible to help this process and what is necessary for this.

So. If to stop a sending of pulses from CNS, which should go through motoneurones, the leg can not move. Now with external assistance we bend a leg. The flow of nervous pulses are directed to a brain and it now can share all axones, which are in a restored nerve, on sensor and motor (through sensor ones the pulses go). As some of proprioceptors in this moment are stretched, other are constricted, there is an opportunity to share them into two groups appropriate to muscles-extensor and muscles-flexor. Changing speed of bending or unbending of a limb in a joint, in addition it is possible to share axones on giving the information about speed and about lengthening. In extreme positions sinew receptors can be activated and are identified.

On time of delay of pulses coming in a brain, it can determine, on what distance from a brain are sensors. Taking into account, that the information, which should be processed, is stored not for long, the process of change of a angle in a joint is necessary to repeat frequentative.
Further a more difficult problem arises - to share the second group of neurones on motor ones and gamma-motoneurons, to find their arrangement in muscles-antagonists etc. And a final stage - "to start" moving units.
Such "linear" concept very schematically describes the reality. The allocated ways for pulses from concrete sensor not exist. On all way of pulses to analytical centres due to connection between neurones the constant summation and branching of the information between various neurones occurs, a duplication of the information in different departments of a head brain and on the contrary, allocation to the certain attribute.
But, at least, from this consideration it is clear, that because we deal with work of a system of information processing, it is necessary to have first of all an adequate input information. Secondly - irrespective of a place of a defeat of nervous system (a peripheral nerve, neuraxis, cerebrum), if the restoration is possible, the process of re-informing of analytical circuits will be realized by a standard way - processing of the input information, development of instructions, comparison of the result with being available in a memory, comparison with work of the symmetric not struck departments of a body, optimization for maximum similarity, profitability and speed of instruction fulfilment.

It is possible to assume, that there is some speed of formation of new connections, which depends on volume and completeness of the input information, its intensity. If the input information is optimum, the speed of re-informing is maximal. On this process the component of formation of long-term memory is imposed, and then the process becomes irreversible. .

to page THEORY