Overview of Proprioceptive Neuromuscular Facilitation (PNF)

Definition:

Method of promoting or hastening the response of one neuromuscular mechanism, through stimulation of various neurological pathways.  This is done by placing specific demands on the patient’s nervous system to assure a desired response which is/are related to normal response of the neuromuscular mechanism.  Based on the assumption that each patient has potential.


Purpose:

To effect levels of neuromuscular activity and therefore influence motor control.

Goals:

To restore voluntary and active range of motion. Return the patient to original strength and range of motion.

Pain free range of motion.  Patient should be able to move his/her body part through the entire range of motion without pain.

Use of maximal resistance.  The motor learning effect of the exercise is enhanced with the use of resistance.  Overload the muscle group involved for an increase in strength.
Relaxation of the body part before strengthening.  Increase the range of motion before beginning strengthening.
Use diagonals, spirals patterns for strengthening.  Joint integrity is enhanced by the rotation component.

Neurophysiologic Properties of Contractile Tissue

  1. Muscle Spindles: The muscle spindle is the major sensory organ of the muscle.  It monitors the velocity and duration of the stretch.
  2. Golgi Tendons Organs: GTO is sensitive to the tension in a muscle.  When excessive tension develops in a muscle, the GTO fires and causes the muscle to relax.
  3. Neurophysiologic Response:
    a) If a muscle is stretched at too high a velocity, the muscle spindle contracts and tension increases in the muscle.  This is known as the monosynaptic stretch reflex.

    b) If a slow stretch is applied to the muscle, the muscle lengthens due to the GTO firing and inhibiting the tension.

Neurophysiological Principles:

  1. Irradiation: Spread of excitation through the body part.  Strong voluntary contractions will cause irradiation to other parts of the body.
  2. Successive Induction (Sherrington’s Law): After a final common pathway has been used in one direction, then response in the opposite direction will be augmented.  Use of the flexor muscle group will cause an increase facilitation of the extensor muscle group.
  3. Reciprocal Innervation (Inhibibition): In order to increase the length of the agonist muscle group, an isometric contraction of the antagonist muscle group in needed.

Basic Principles of PNF:

  1. Manual Pressure – Placement of hands in direction of the desired movement.
  2. Verbal Stimulation – Use the correct wording to achieve the desired movement. “Push – Pull”.
  3. Visual Stimulation – Show the patient how to do the desired movement.  Give starting and end points to the patient.
  4. Joint Integrity – a) Traction (stretch) – Elongation of all the muscle of the pattern against gravity. b) Approximation – Pressure through the long axis of the structure, distal to proximal, with gravity.
  5. Quick Stretch – Trigger the stretch reflex of the muscle spindles.  Not necessary in orthopedic problems.  (Not used with pain).
  6. Maximum Resistance – Amount of resistance, which allows the patient to move rhythmically and pain free through the entire range of motion.  Graded to each patient and his/her pain. a) Isotonic  b) Isometric – Build up tension to maximum and maintain until strength starts to decline, then gradually release.
  7. Patterns – Use linear, functional patterns.  Patterns are diagonal and spiral.
  8. Timing – Distal to proximal or proximal to distal.  Use the stronger components to irradiate to the weaker.  (P to D means strong P to irradiate D).  (D to P means strong elbow to irradiate weak shoulder).

Techniques of PNF:

  1. Rhythmic Stabilization – Isometric
    a) Take to point of pain
    b) Hold in the pattern isometrically until patient begins to tire.
    c) Change resistance to antagonist muscle group and hold without allowing the body part to move.
    d) Work the tight muscle first.
    e) Be sure to work the rotation.
  2. Hold – Relax – Works the agonist
    a) Move body part to point of tightness.
    b) Contract with the tight muscles isometrically.
    c) Move to new range of motion either actively or passively.
  3. Contract – Relax – Antagonist
    a) Move body part to point of tightness.
    b) Contract isotonically with antagonist muscles – rotation movement only.
    c) Move to new range and repeat.
  4. Repetitive Initiation
    a) Stretch and guide through the pattern until the patient learns the pattern.
    b) After learning the pattern gradually increase the resistance.

Strengthening Technique

  1. Slow Reversal – Patterns
    a) Work in pattern through range of motion.
    b) Apply maximal resistance to allow patient to move through entire range normal speed.
    c) Start reversal before patient has finished previous pattern.
  2. Repeated Contractions
    a) Begin working in pattern until you find weak point in range of motion.
    b) At that point build up resistance to isometric and hold.
    c) Then pull back and move forward again.
    d) Repeat several times.
  3. Rhythmic Stabilization – see above

Eccentric Contractions

  • Used to develop deceleration abilities and proprioception.
  • Agonist Reversals

PNF Techniques (Uses and Goals)

Increase AROM Decrease Pain Initiate a Motion
Teach a Motion Develop Strength Stability
Proprioception Endurance Restore Function

Techniques of PNF

Relaxation

Hold-Relax Contract Relax Rhythmic Stabilization

Strength/Coordination/Proprioception

Slow-Reversals Repeated contractions Agonist Reversals
Rhythmic Stabilization Combination of Isotonic contractions

R-C-H, R-C-H-A-R

Direct and Indirect Treatment

Direct Treatment Indirect Treatment
Use of treatment technique on the affected region of motion. Use of treatment technique on unaffected segment.
Treat involved part of body. Direct patient’s attention to work less affected part of body.
Direct patient’s attention to
stabilizing or moving.
Use strong segment or movements
to facilitate weaker movements.
Affected segment.

Relaxation Techniques Neuro-Physiological Mechanical: Basis

GTO influence

Reciprocal Inhibition

Motor unit fatigue

Contractile component elongates series elastic component of muscle

Rotation facilitates relaxation (C-R)

Recurrent and supra-segmental inhibition

Agonist Reversals: Strengthening Technique

Used to promote a lengthening contraction in a pattern

Used to facilitate proprioception

A shortening contraction is performed followed by a lengthening
contraction in the same pattern

A hold may be added at the transition of the R-C and the A-R to
increase motor unit recruitment

Agonist Reversals: Neuro-Physiological Basis

  • Eccentric contraction promotes external and internal stretch of muscle spindles
  • Take advantage of elastic energy storage capacity
  • Increases motor unit recruitment

Vary the Effect of Techniques – 2

  • Change activity of intermediate pivot to effect two joint muscles
  • Emphasize hamstring = use hip pivots Flex-Add-ER: Knee Extension to Knee Flexion
  • Emphasize Elbow Flexors = Shoulder pivots Flex-Add-ER with Elbow Extension to Elbow Flexion

Vary the Effect of Techniques – 3

  • Change athlete’s body position to alter effects of gravity
  • Work hip Abductors against gravity = Place athlete in side lying position: Use R-C at hip pivot
  • Extension- abduction- internal rotation

Vary the Effect of Techniques – 4

  • Change athlete’s body position to a more functional position
  • Upper Extremity: Sitting position for an overhead activity = R-C Flex- Abd- ER: Hitting activity in Volleyball
  • Lower Extremity: Standing Position supported by parallel bars or stationary bike handlebars = R-C Flex-Abd-IR: To improve hip knee function in running.