Range of motion

The neutral zero method ( NNM, zero-crossing method ) is a standardized orthopedic assessment and documentation index for the mobility of joints. It is expressed as a code which represents the amount of movement of a joint in degrees around a certain axis. In this way, the mobility clearly traceable and findings and letters can be documented. On the basis of known standard values ​​, a motion restriction thus be evaluated and used as a basis for expert opinion (see Anatomical position and directional terms ).

Range of motion

The freedom of movement is indicated as maximum deflection of the joint from the neutral position in degrees, the neutral position is indicated by 0 °. Starting point is the "neutral position ": The man stands erect, arms hanging relaxed downward directed the thumb forward and the feet are parallel. This usually means that the elbow and knee joints are not completely straight but slightly bent. The adjacent angles are defined as the zero position. This neutral zero position corresponds closely to the anatomical zero position ( anatomical normal position ), but at which point the palms facing forward.

To describe the mobility must be pre- specified, tested in which directions. On the part of the German statutory accident insurance has established itself as the first angle, the deflection in the distal direction ( stretching (extension), outward movement (abduction ) or eversion ( external rotation, supination ) etc) specified. The second angle is normally 0 ° ( = neutral), the third angle describes the displacement in the proximal direction (flexion (flexion ), inward ( adduction) or pronation ( internal rotation, pronation ) ). However, there is no binding standard, so that the movement extent also the other way around can be specified, eg Flexion / extension instead of stretching / bending, with a correspondingly reversed ranking of degrees - which changes nothing in the actual statement.

The normal, undisturbed range of motion of the elbow joint is in extension / flexion 10 ° -0 ° -150 °. The degree sign is not listed in the rule. This means that the arm

In joints with a plurality of degrees of freedom, a data record is provided for each axis. For the hip joint, the normal values ​​are therefore:

  • Extension / flexion: 10-0-120
  • Abduction / Leadership: 45-0-30
  • External rotation / internal rotation: 50-0-40

Special cases

Can the neutral position of the joint is not reached, eg due to damage or during the entire movement not be reached, the value 0 appears no longer in the middle, but on the side where the deficit exists.

A typical example is the restriction of movement at the elbow joint after a fracture involving the joint. Here is the maximum diffraction limited at 100 °, the stretching but only to 30 ° flexion possible, ie, with loss of extension 30 °, is the condition: extension / flexion 0-30-100.

In the case of equinus, in which the neutral position (= 0 ° ) of 90 ° is not reached between the lower leg and foot axis axis, the finding is, for example, dorsiflexion / plantar flexion 0-15-30 and describes a deficit / a equinus of 15 °. The foot is consistently in flexion ( plantar flexion ). Note that the movement of the foot to the top (that is, toward the head ) and stretching ( dorsiflex ) and the downward movement (that is, the bottom ) as diffraction ( plantar flexion ) are defined.

In the case of ankylosis with fixed joint position or after a joint fusion ( arthrodesis ), for example, in 20 ° flexion is, the findings flexion / extension 20/20/0 - this corresponds to a range of motion of 0 ° and an extension deficit of 20 °.

Documentation

To document the findings collected exist in the area of the German Social Accident Insurance standardized measurement sheets for upper and lower extremities. These measurement sheets contain the standard values ​​of movement except for all joints and clarify the systematics of the documentation of findings. They are used in Germany except in the region of the GUV and private accident insurance and other, such as social -court assessments.

For a statistical evaluation of the data in the form of the neutral zero method can not be use, but must then be reshaped in such a way that only two entries for the two directions of movement remain, so instead of flexion / extension 150/0/10 can be used as variables only diffraction = 150 and process elongation = 10. Can not be reached the neutral position, the corresponding variable is negative, so instead of flexion / extension 100/30/0 are the variables diffraction = 100 and extension = -30, which corresponds to the extension deficit. From this it is also very easy range of motion (range of motion ROM) calculated as the sum of the two variables - corresponding to 160 ° in the first and 70 ° in the second example. This system and V.A. range of motion (ROM) are widely applied outside the German-speaking world, the neutral zero method is largely unknown.

In addition to the measurement of passive mobility in the context of reports are for the clinical study, the measurement of the active and active - assisted movement amounts of great importance, since they determine the actually usable in everyday range of motion. Under the spasticity can also be made between the amount of movement in the passive slow motion and the passive rapid movement, which corresponds to the periphery of which is restricted by the spasticity movement, since faster movement the spastic muscles contract much earlier, thereby reducing the daily relevant range of motion.

599697
de