Proprioceptive Neuromuscular Facilitation
Objectives:
To understand how proprioceptive information is used in PNF stretching and strengthening techniques.
To get hands-on experience in PNF techniques used in assessment and rehabilitation.
Definition of PNF:
Hastening the response of the neuromuscular mechanism through stimulation of the proprioceptors; could result in either facilitation or inhibition.
Mechanisms of PNF:
Autogenic inhibition: inhibitory signals (from GTOs) override excitatory impulses (from muscles spindles) causing gradual relaxation.
Reciprocal inhibition: contraction of agonist muscle elicits relaxation of antagonist.
Stretch Reflex: sudden stretch of muscle spindle causes agonist to contract and antagonist to relax (ie., patellar tap reflex)
Basic Principles:
Patterns of movement - should be taught to patient
Visual stimulus - look at moving limb
Verbal cues - to coordinate reflex and voluntary movements
Manual contact - to resist and direct
Proper mechanics - body positioning of therapist
Resistance - should be maximal
Rotational movement - for maximal ROM
Normal timing - proper sequence of muscle contraction
Timing for emphasis - to affect specific points on a range
Traction or approximation - for extra proprioceptive response
Quick stretch - facilitates greater muscular contraction
Strengthening:
Rhythmic initiation: a progression of 1) initial passive, 2) active-assistive, and 3)active movement through the agonist pattern.
Rhythmic stabilization: an isometric contraction of the agonist followed by an isometric contraction of the antagonist.
Repeated contraction: an isotonic contraction against maximal resistance both concentrically and eccentrically throughout the range of motion.
Slow Reversal: isotonic contraction of the agonist followed immediately by an isotonic contraction of the antagonist.
Slow reversal-hold: an isotonic contraction of the agonist followed immediately by an isometric contraction.
* all can employ quick stretch to facilitate muscular activity
a. Rhythmic Initiation: P-ROM, active-assissted, MRE
b. Rhythmic Stabi1ization: "HOLD"
c. Repeated Contraction: "PUSH/PULL" (INSERT QUICK-STRETCH)
d. Slow reversal: "PUSH-PULL"
e. Slow reversal-ho1d: "PUSH-HOLD, PULL-HOLD"
Stretching:
Contract relax: isotonic contraction of the antagonist followed by passive stretch
Hold-relax: isometric contraction of the agonist followed by passive stretch
Agonist contract-relax: body part is moved actively in the agonist pattern via isotonic contraction of the agonist (active stretch).
Slow reversal-hold-relax: isotonic contraction of the antagonist followed by an isometric contraction of the agonist followed by a relaxation phase.
Stretching (hamstring stretching example)
a. Contract-Relax: PUSH through ROM, then RELAX
b. Agonist Contract-Relax: HOLD, PULL
c. Slow Roversal-Hold-Re1ax: PUSH, HOLD, PULL
Vll. MOVEMENT PATTERNS
A combination of rotational and diagonal movements.
UPPER EXTREMITY
Dl into FLEXION from: HITCH HIKE to: SWAT fly
Dl into EXTENSION from: SWAT FLY to: HITCH HIKE
D2 into FLEXION from: HAND IN OPPOSITE POCKET to: CARRY TRAY
D2 into EXTENSION from: CARRY TRAY to: HAND IN OPPOSITE POCKET
LOWER EXTREMITY
D1 into flexion from: FOOT OUT AND AWAY to: CROSS LEGS
Dl into EXTENSION from: CROSSED LEGS to: FOOT OUT AND AWAY
D2 into FLEXION from: DISTAL LEGS CROSSED to: SOCCER WIND UP
D2 into EXTENSION from: SOCCER WIND UP to: DISTAL LEGS CROSSED
Note: Trainer may use limited ROM pattorn
Discussion Questions:
1. What are the possible advantages of PNF over other stretching/strengthening techniques?
2. Why are there so many techniques? In what specific conditions would each of the techniques be used?
3. Under what conditions should PNF techniques not be used?