3.1: Proprioceptive Neuromuscular Facilitation

Figure \(\PageIndex{1}\)

Although there has been a paradigm shift in recent years, from a historical perspective, it is important to understand that PNF and NDT both developed from a philosophical belief that in order to recover from a neurological injury, no matter what age you were, you must go through stages of control/development. These treatment techniques are based on a reflexive and neurofacilitation rehabilitation model, making accurate hand placement and manual techniques critical. Current research indicates that the most important way to improve function in persons following neurological injury is to train function. However, this does not mean that strengthening or increasing PROM, with a technique such as PNF, is not indicated. What can be inferred from the literature is that by itself, a PNF pattern is not likely going to improve a functional activity such as reaching. The task of reaching must be trained within a variety of contexts. So, if you are using a neurofacilitation technique, always remember to follow-up with training the task. Performance of the relevant task, without the need for manual facilitation, is the ultimate goal.

The defining elements of PNF include diagonal patterns of movement, combined with specific hand contacts providing facilitation to the muscle spindle. This is required, in order to encourage its reflexive activation of the muscle. The patient is also encouraged to recruit muscles voluntarily to complete a pattern. If the facilitation is removed or delivered incorrectly, the outcome of the desired movement may be affected.

Body Position

Note

The therapist's body position is as important a component as the patient's. Both are essential to the facilitation of the desired response in the patient.

Therapist: The therapist should be positioned at either end of the diagonal, with the mid-sagittal plane of the therapist parallel to the line of movement desired (the therapist belt buckle will face the motion). The choice of which end is based on: best direction of force reception, the amount of space, best position for visual input, or the individual therapist's preference. The therapist needs to resist each pattern in a line parallel to her or his midsagittal plane. MOVEMENT SHOULD ALWAYS BE DIRECTLY INTO OR OUT OF THE CENTER OF GRAVITY OF THE THERAPIST. With the upper extremity patterns, it is often easier to position the therapist at the shoulder and go through a \(180^{\circ}\) pivot as the motion passes the mid-point of its’ arc. It is still important to get the therapists’ mid-sagittal plane facing the motion at the beginning and end of the motion.

Patient: The patient should position themselves with body parts in the most comfortable position and with all parts in as close to proper alignment as possible for normal physiological movement. Support the normal curves of the body, e.g.. lumbar lordosis in supine, cervical spine in side lying, waist in side lying. For extremity patterns done in supine, it works better to get the patient as close to the edge of the support surface and is safe.

Body Mechanics

Note

The movement of the therapist directly influences the response of the patient and should enable the patient to move correctly and freely in the diagonal. Key points to remember:

• The therapist's spine is most stable in neutral rotation and lateral flexion: AVOID ROTATION OR LATERAL FLEXION OF THE SPINE DURING PNF!
• The majority of the movement should come from the legs and hips.
• The therapist should always move or shift weight in the direction of movement desired from the patient.
• Arms and hands should stay relaxed, and the majority of the resistance should come from the therapist's trunk and pelvis.
• The therapist's center of gravity stays even with the arc of movement of the patient; if the center of gravity of the therapist becomes lower than the movement of the patient, there is more therapist work due to increase in patient's mechanical advantage.

Clinical Tips

• Manual contacts may vary between individuals. The best contact is that which facilitates the correct response in the desired direction.
• Remember, gravity alone may be enough resistance to facilitate the desired response.

Manual Contacts:

Note

"Appropriate" hand placement is essential to facilitate the desired response in the patient. Manual contacts LEAD the desired motion and must oppose the desired motion. Manual contacts need be specific and follow one of two rules. The contact surface needs to be the most precise and direct surface to resist the desired motion or it needs to contact the specific agonist muscle, or muscle group in order to facilitate that muscle and be on a surface that resists the desired motion. The role of the manual contact is to increase the stimulation of the skin and other receptors to enhance the desired motor response.

Lumbrical Grip: This manual contact utilizes the intrinsic muscles of the hand, allowing for a comfortable, specific, and secure contact. The key contact points are the palm of the hand, specifically the thenar and hypothenar eminences, the entire palmar surface of the fingers, and the FINGER PADS, not the tips! REMEMBER: Point pressure produces PAIN & WILL INHIBIT THE DESIRED RESPONSE!

Quick Stretch: Immediately prior to commands for muscle contractions, a quick stretch of the agonist muscle enhances the agonistic muscle contraction. The therapist does the quick stretch at the end of the lengthened range of the agonist. The therapist applies the stretch to as many of the agonistic muscles in the given pattern as practical. This quick stretch is intended to trigger a reflex muscle contraction that coincides with the initiation of the client's voluntary contraction. The therapist times the quick stretch with the client's contraction by giving a verbal cue ["and....pull (or push)"] in which the quick stretch immediately precedes the "pull" or "push" commands the voluntary contraction. The therapist finetunes the client's response by adjusting the delay between the quick stretch and the "pull" or "push".

Appropriate Resistance:

The amount of resistance should allow for smooth, coordinated, and appropriate speed of contraction throughout the available range of motion. Over-resisting leads to halting or too slow motion. The amount of resistance will vary through the range to facilitate smooth flow of the desired response. Resistance will be greater where the patient has most strength and mechanical advantage and less where the motion is weaker.

Use resistance for any of the following:

• strengthening
• increasing range of motion
• increasing stabilization
• enhancing relaxation
• enabling appropriate speed of contraction
• increasing coordination 

Definition: Isotonic

Concentric, eccentric, maintained; the command and intent is always for movement though at times little movement may occur (commands are “push!” or “pull!”).

Definition: Isometric

The command and intent is to maintain the position in space (command is “hold!”).

Verbal and Visual Cues:

Verbal commands assist in developing communication between the therapist and patient. The brevity, specificity, and timing of verbal cues are critical to optimal patient response. Visual input is key to developing coordinated use of the body, especially in cases of sensory loss. One or two word commands are BEST; let your hand placement and tactile cues communicate the rest of the instructions. Make sure that the patient WATCHES their motion while learning each pattern.

Both are used to:

• Identify the desired direction of movement.
• Facilitate the amount and type of response desired.
• Direct the movement of the body with the movement pattern desired.

Techniques:

The following key techniques will be described, with video demonstrations of the techniques with the use of different patterns.

• Quick Stretch
• Rhythmic Initiation
• Repeated Contractions
• Slow Reversals
• Hold Relax
• Contract Relax
• Rhythmic Stabilization
• Alternating Isometrics
• Resisted Progression

Remember that these techniques can facilitate the desired response for most movements of the limb girdles, extremities, or whole body.

Rhythmic Initiation:

Begins with passive motion to familiarize the client with the desired direction and sequence of motion. Rhythmic initiation progresses to active motion to teach the client to do the motion. Finally rhythmic initiation progresses to resisted movements that enable strengthening the motion to functional levels. It usually works best to have the client initiate the movement with the distal components first. That way the therapist can use their distal hand better to guide the motion. This technique is always uni-directional in a PNF pattern. Use Rhythmic Initiation to teach the desired pattern of movement and to assess the range of motion and gross strength. Can work effectively to improve:

• speed of movement
• direction of movement
• quality of movement
• strength or endurance

Repeated Contractions:

Used with isotonic contractions that are weaker at some point(s) in the range of motion. The therapist repeats the quick stretch and the verbal cue whenever the motion slows below the desired pace or weakens. This enhances the active control of the motion and strength. At the point in the range of motion where the contraction weakens, repeat the initial quick stretch and verbal command (i.e. "and pull farther” or “pull harder") and reduce your resistance. When the motion slows too much, reapply your quick stretch, reduce you resistance, and command “pull faster”. Be sure that you allow the motion to be fast enough by “yielding your resistance” at the correct speed.

Reversals of Antagonists:

Reversal of Antagonists includes contraction of the agonist followed by contraction of antagonist. This facilitates coordinated “changes of direction” in a movement pattern for daily function. This technique first commands motion in one direction of a diagonal pattern then (after a quick change in therapist manual contact) commands the opposite direction of motion. It is a repeating cycle of alternating contractions of antagonistic muscle groups. Slow reversal works on isotonic contractions and promotes smooth reversal of motion. Rhythmic stabilization works on isometric contractions and promotes stability at the target joint.

1. Slow reversals: Reversal of isotonic contractions through all or part of the available ROM. Commands might be (therapist uses manual contact to resist agonists) "now push”, client goes through one direction of the motion; (therapist changes manual contacts to resist antagonists). Therapist commands “now pull" and client returns in the opposite direction of the motion. Used to improve:
   • dynamic strength
   • coordination
   • kinesthetic awareness
   • endurance
   • active range of motion
2. Rhythmic stabilization: Isometric contraction of antagonistic muscle groups either simultaneously or alternately. Commands would be (therapist uses manual contact to resist agonists) "now hold"...(therapist changes manual contacts to resist antagonists)...”now hold”. To achieve a maximal response, it is necessary to resist both the diagonal and rotational components. Compression into the proximal joints will further facilitate stability. 

Used to improve:

• stability
• control of posture
• balance
• relaxation and pain reduction
• range of motion 

Combination of Isotonics:

Combination of Isotonics involves concentric (shortening) and eccentric (lengthening) contractions in one direction, without any relaxation. They promote controlled strong movements through some or all of the available ROM. There are three types of contractions: concentric, eccentric, and maintained isotonics (alternate concentric and eccentric). Commands might be "pull your hand up.......let me pull it down slowly" repeat this for several cycles as appropriate to the target ADL. Daily function consists of the coordination of all three types of muscle contractions. Combination of isotonics is particularly helpful when patients are limited in strength or smooth control in specific points in the range of motion. The ultimate goal is re-integration into functional activity. Generally used to improve:

• strength in a focused part of the ROM
• the ability to alternate between concentric and eccentric contractions
• better control of more range of motion
• initiation of movement in different parts of available range

Many activities do not occur throughout the entire available range of motion. For example, sit to stand from a high chair, or walking down stairs. An individual may have no functional problems in mid-range, but may not function well at the shortened or lengthened extremes of muscle range of motion. An example is the common difficulty patients have in controlling descent into a low chair. The quads just get beyond their optimal length for eccentric control and the client “plops” into the chair. In this case the therapist might do combination of isotonics in the range of hip and knee motion associated with a low chair. Then the patient would progress to practicing controlled sitting on lower and lower chairs.

Hold Relax:

This technique is effective for increasing ROM due to muscle tightness and also works well in the presence of mild to moderate pain. The key to effective hold relax technique is applying and releasing the resistance in a smooth and gradual way to minimize patient discomfort. This way the therapist can regulate the resistance so that it does not increase the pain. If pain persists with gentle contractions or prevents significant relaxation, try gentle active assistive exercise first.

Hold Relax description: Take the extremity through the available ROM to where the restriction begins, but client is still comfortable. Gently resist all components of the tight muscle pattern, with emphasis on rotation. Commands might be "hold gently..now a little stronger...hold...now let go some...now relax completely". MAKE SURE THE CLIENT RELAXES FULLY, this is critical. Next the therapist moves the extremity further into the well-tolerated restricted range (but not to the point of pain) and repeats the hold….relax. The therapist repeats the cycles until there is no further gain in ROM. Gentle traction during the contractions helps minimize joint pain. Can do Hold Relax by contracting the “tight” muscles (providing improved direct relaxation after the contraction) or by contracting the “opposite” muscles (enabling improved relaxation of the tight muscles indirectly, by reciprocal inhibition).

Hold Relax is useful for:

increasing range of motion (with and without mild to moderate pain)

initiation of movement

Contract Relax:

Contract Relax uses a concentric contraction of the tight muscle (direct relaxation), or of the opposing muscles (indirect relaxation) and is otherwise much like Hold Relax. Resist all components of the pattern with concentration on rotational component. Do not allow any significant motion through the ROM. The contraction is followed by complete relaxation of the body part, and active or passive movement in the direction that lengthens the restricted soft tissues. Commands might be "pull...pull...pull...now relax...let go completely". THIS TECHNIQUE IS NOT Preferred WHEN PAIN IS PRESENT IN THE MOVEMENT PATTERN. (The reason that Hold Relax works better in the presence of pain is that the therapist controls the gradual onset of contraction and can much better KEEP the contractions gentle enough. In Contract Relax, when a therapist gives a “Pull” or “Push” command, the client determines how much he/she will pull or push. In the presence of pain, clients have muscle guarding and find it difficult to push or pull just a “little”.)

Contract Relax is useful for:

range of motion (only without pain)

initiation of movement

The following chart provides a summary of PNF in relation to Margaret Rood's (one of the foremothers of physical therapy) Stages of Control. Although originally describing only developmental stages of motor control, the concepts were expanded to the recovery of movement in adults. With current evidence, it is understood that the nervous system of adults recover differently than the nervous system develops in children. However, Rood has provided a conceptual framework into which the application of the different elements of PNF can be organized.

STAGES OF CONTROL	GENERAL GOALS	PNF TECHNIQUES	SAMPLE TREATMENT ACTIVITIES
MOBILITY	Increase ROM Increase initiation of range of motion	Hold Relax (HR), Contract Relax (CR), Rhythmic stabilizations (RS), Rhythmic rotation, Joint mobilization HR-active movement, Repeated Contractions	For a patient with decrease in shoulder joint mobility, incorporate Rhythmic Rotation into PROM exercises to facilitate relaxation, especially in a patient with pain and hypertonia. For a patient with a limitation in ROM, particularly when pain is accompanying, Hold Relax can be used which includes an isometric contraction at the end point of the range, followed by relaxation and movement to new point of limitation.
STABILITY	Sustained isometric contractions in shortened range for increasing duration Coordinated isometric contractions in midline or weight bearing postures	Shortened-held resisted contractions (SHRC) Alternating Isometrics, RS	For a patient who has difficulty standing maintaining LE extension, SHRC as a Quad and Glut set in supine, held for 10 seconds to gain stability across the joints in non-weight bearing to prepare for weight-bearing. For a patient with difficulty stabilizing in standing or sitting and in order to facilitate smooth performance of isometric contractions in all three planes simultaneously, you could use RS at the trunk.
CONTROLLED MOBILITY	Weight-shifting in weight bearing postures: AP, lateral, rotation. Also, reversal of antagonists or concentric-eccentric contractions; trunk rotations	Slow-reversal hold, slow reversal, agonistic reversals	For the patient who shows difficulty in eccentric contractions in stand to sit, you could have the patient in the position and have the patient “make you work at pushing him/her down” into sitting using the technique of agonistic reversals.
SKILL	Proximal dynamic stability Normal timing and sequencing of movement Trunk counter-rotation Locomotion and Manipulation (ADLs) Communication	Shortened-held resisted contractions (SHRC) Alternating Isometrics, RS	For a patient who has difficulty standing maintaining LE extension, SHRC as a Quad and Glut set in supine, held for 10 seconds to gain stability across the joints in non-weight bearing to prepare for weight-bearing. For a patient with difficulty stabilizing in standing or sitting and in order to facilitate smooth performance of isometric contractions in all three planes simultaneously, you could use RS at the trunk.

Table \(\PageIndex{1}\): Stages of Motor Control Associated with Proprioceptive Neuromuscular Facilitation