Chapter 4 ther. Ex. Stretching for impaired MOB

Grade II microfailure (later plastic range)

rupture of an increased number of fibers and partial failure after deformation into the later part of the plastic range.

Grade I microfailure (early plastic range)

rupture of some fibers after deformation into the early part of the plastic range.

Inhibition (neuromuscular system)

a state of decreased neuronal activity and altered synaptic potential, which diminishes the capacity of a muscle to contract.

Stretch reflex (Neurophysiological Response of Muscle to Stretch)

an increase or facilitation of active tension in the muscle being stretched. -This increased tension resists lengthening and is thought to compromise the effectiveness of the stretching procedure. -To minimize activation and the subsequent increase in muscle tension, a slowly applied, low-intensity, prolonged stretch is considered preferable to a quickly applied, shortduration stretch.

Proprioceptive Neuromuscular Facilitation (PNF) Stretching Techniques

sometimes referred to as active stretching or facilitative stretching, integrate active muscle contractions into stretching. -increase the likelihood that the muscle to be lengthened remains as relaxed as possible as it is stretched. -increase flexibility and ROM -require that a patient has normal innervation and voluntary control of either the range-limiting target muscle or the muscle on the opposite side of the joint. these techniques cannot be used effectively for patients with paralysis or spasticity resulting from neuromuscular diseases or injury. because these stretching procedures are designed to affect the contractile elements of muscle, as opposed to noncontractile connective tissues, they are more appropriate to use when muscle spasm limits motion and less appropriate for long-standing fibrotic contractures. Types: ■ Hold-relax (HR) ■ Agonist contraction (AC) ■ Hold-relax with agonist contraction (HR-AC) -always performed with combined muscle groups acting in diagonal patterns.

High-velocity stretching (speed of stretch)

***Only for specific patient -a highly trained athlete involved in a sport, such as gymnastics, that requires significant dynamic flexibility may need to incorporate high-velocity stretching in a conditioning program. -young, active patient in the final phase of rehabilitation who wishes to return to high-demand recreational or sport activities after a musculoskeletal injury.

Adaptation

- an increase or decrease in the number of sarcomeres, to prolonged positioning is transient, lasting only 3 to 5 weeks if the muscle resumes its pre-immobilization use and degree of lengthening for functional activities -this underscores the need for patients to use full-range motions during a variety of functional activities to maintain the stretchinduced gains in muscle extensibility and joint ROM.

pseudomyostatic contracture (false muscle)

-An apparent permanent contraction of a muscle due to a CNS lesion, resulting in loss of ROM and resistance of the muscle to stretch. -shortened due to increased tone however with inhibition of tone, muscle can reach full length EX: causes of= cerebral vascular accident, a spinal cord injury, or traumatic brain injury patient with a muscle spasm or guarding

Effects of immobilization (changes in collagen affecting stress-strain curve)

-Cause collagen bond to weaken -tissue failure increase at a decreased % max load (weakness) -decrease in stiffness -reduction in energy absorption

Contractile tissues (muscles)

-Elastic= tissue returns to pre-stretched length after stretch force is removed. -Plastic= is the tendency of soft tissue to assume a new and greater length after a stretch force is removed.

Non-contractile tissues (tendon, ligament, skin)

-Elastic= tissue returns to pre-stretched length after stretch force is removed. -Plastic= is the tendency of soft tissue to assume a new and greater length after a stretch force is removed. *Viscoelasticity= time dependent (soft tissue) initially resists deformation, such as a change in length, when a stretch force is applied but will slowly lengthen if the force is sustained. Will gradually return to its prestretch configuration after the stretch force is removed.

Hypermobility

-Excessive range of motion in a joint, making it less stable and more susceptible to injury. -Instability of a joint often causes pain and may predispose a person to musculoskeletal injury. -selective hypermobility= healthy individuals w/ normal strength/stability to participate in activities that require extensive flexibility.

Benefits/outcomes of stretching

-Increased Flexibility and ROM -general fitness= stretching exercises routinely are recommended for warm-up prior to or cool-down following strenuous physical activity. -Injury prevention and reduced post-exercise muscle soreness= it is not likely that stretching exercises prevent or reduce injury risk. -Enhanced performance= acute dynamic stretching appears to lead to enhanced performance, especially with longer duration stretches (>90 seconds).

Morphological changes (Response to Immobilization and Remobilization)

-Muscle atrophy/weakness will occur -atrophy occurring more quickly and more extensively in tonic (slow-twitch) postural muscle fibers than in phasic (fast-twitch) fibers. -can begin within a few days/week -significant deterioration of motor unit recruitment

Importance of Strength and Muscle Endurance

-Muscle strength/tensile strength of noncontractile tissues decrease with immobilization -it is critical to include low-load resistance exercises to improve muscle performance (strength and endurance) as early as possible in a stretching program. -Initially, emphasis should be on developing neuromuscular control and strength of the agonist, the muscle group opposite the range-limiting target muscle. -As ROM approaches a "normal" or functional level, the muscles that were range limiting and then stretched must also be strengthened to maintain an appropriate balance of strength between agonists and antagonists throughout the ROM.

Mechanical properties for stretching CT

-Permanent changes in tissue length or flexibility requires breaking of collagen bonds and realignment of the fibers. -Microfailure that induces permanent lengthening can occur through creep, stress-relaxation, and controlled cyclic loading. -Healing and adaptive remodeling capabilities allow the tissue to respond to repetitive and sustained loads if time is allowed between bouts= increases flexibility and tensile strength of tissues. -If the inflammation from the microruptures is excessive, additional scar tissue, which could become more restrictive, is laid down.

Cold

-Prior to stretching reduces muscle tone -makes the muscle less sensitive during stretch in healthy subjects -While the use of cold immediately after soft tissue injury effectively decreases pain and muscle spasm, once healing and scar formation begin, cold makes healing tissues less extensible and more susceptible to microtrauma during stretching. -reduces muscle soreness and shown to promote a more lasting increase in soft tissue length

Elastin fiber (composition of CT)

-Provide extensibility -great deal of elongation with smaller loads -fail abruptly w/o deformation at higher loads. -more elastin= more flexibility -may lengthen 150% w/o failure

Preparation for stretching

-Review goals/functional outcomes -Select effective/efficient stretch techniques -Warm up soft tissues -put patient in stable comfortable position -explain procedure to patient -make sure area is free of clothing -try and get patient to remain relaxed and work within their tolerance level.

irreversible contracture (fibrotic contracture)

-The longer a fibrotic contracture exists or the more extensive the tissue replacement, the more difficult it becomes to regain optimal mobility and the more likely it is that the contracture will become irreversible. -Although it is possible to stretch a fibrotic contracture and eventually increase ROM, it is often difficult to re-establish optimal tissue length.

selective stretching

-a process whereby the overall function of a patient may be improved by applying stretching techniques to some muscles and joints while allowing motion limitations to develop in other muscles or joints. -typically in patients with permanent paralysis, trunk stability for posture, wrist extensors to assist w/ grasping.

Golgi Tendon Organ (GTO) (inhibitory/tension/stress strain curve)

-a sensory organ located near the musculotendinous junctions of extrafusal muscle fibers. -function is to monitor changes in tension of muscle-tendon units. -When muscle tension develops, it activation signals to the spinal cord inhibit alpha motoneuron activity and decrease tension in the muscle-tendon unit. -been shown to have a low threshold for firing, functioning to continuously monitor and adjust the force of active muscle contractions during movement or the tension in muscle during passive stretch.

Cyclic loading

-can cause CT fatigue, leads to stress fractures/overuse syndromes

Effects of Age (changes in collagen affecting stress-strain curve)

-decreases maximum tensile strength and stiffness of tissue, and the rate of adaptation to loading is slower. -increased tendency for overuse syndromes, fatigue failures, and tears with stretching.

Effects of inactivity (changes in collagen affecting stress-strain curve)

-decreases the size and amount of collagen fibers, resulting in weakening of the tissue. -as collagen decrease, elastin increase= increased tissue compliance -physical activity has beneficial effect on strength of CT

Ground substance (composition of CT)

-functions to reduce friction between fibers, transport nutrients and metabolites within the tissue, and maintain space between fibers to help prevent excessive cross-linking between them. -ability to attract/hold water -made of proteoglycans (PGs) /glycoproteins. -PGs= function to hydrate the matrix, stabilize the collagen networks, and resist compressive forces—especially important in cartilage and intervertebral discs. -provide linkage between the main tissue matrix components and between the cells and the matrix opponents.

passive flexibility

-is the extent to which a joint can be passively rotated through its available ROM -depends on the extensibility of soft tissues that cross and surround a joint. -is a prerequisite for—but does not ensure—dynamic flexibility.

Muscle spindle (facilitatory/stretch reflex)

-major sensory organ of muscle -sensitive to quick and sustained (tonic) stretch -small, encapsulated receptors composed of afferent sensory fiber endings, efferent motor fiber endings, and specialized muscle fibers called intrafusal fibers. -when an intrafusal muscle fiber is stimulated and contracts, it lengthens the central portion and activates the sensory receptors in the nuclear bag and chain.

Fibrotic (muscle/CT replaced by fibrosis) contracture

-may occur when normal muscle tissue and connective tissue are replaced with a large amount of nonextensible, fibrotic adhesions and scar tissue or even heterotopic bone. -Permanent loss of extensibility of soft tissues occur that cannot be reversed by nonsurgical intervention. -Healed by stretching and surgical intervention. -Long-term immobilization

Reticulin fibers (composition of CT)

-provide tissue with bulk.

Collagen fibers (composition of CT)

-responsible for the strength and stiffness of tissue and resist tensile deformation. -more collagen= more stability -Continued loading will progressively increase fiber strain until a point where bonds between collagen fibers begin to break. -Failure of tissue at less than 10% increase in length -Tendons= parallel fibers and can resist the greatest tensile load. -Skin= fibers have a random orientation and so are limited in resisting higher levels of tension. - ligaments/joint capsules/fascia= fiber alignment varies so that they can resist multidirectional forces. ***Ligaments that resist major joint stresses have a more parallel orientation of collagen fibers and a larger cross-sectional area.

shortened position (immobilization)

-sarcomere absorption occurs (reduction in muscle length, the number of muscle fibers, and the number of sarcomeres in series within myofibrils) -atrophies and weakens at a faster rate than a muscle immobilized in a lengthened state. -decreasing its capacity to produce maximum tension as it contracts at its normal resting length. -earlier onset of passive tension as muscle is stretched.

Response to stretch (muscle)

-stretch force is transmitted to the muscle fibers through the endomysium and perimysium. -elasticity is the property that allows ____________ to return to its resting length after short-term stretch. -longer lasting/more permanent (viscoelastic or plastic) length increases to occur the stretch force must be maintained over an extended period of time.

Effects of corticosteroids (changes in collagen affecting stress-strain curve)

-subsequent decrease in tensile strength. -corticosteroid injections decrease collagen synthesis and organization, necrosis, and an increased ratio of type III to type I collagen. -There is fibrocyte death next to the injection site with delay in reappearance up to 15 weeks.

contracture

-the adaptive shortening of the muscle-tendon unit and other soft tissues that cross or surround a joint, resulting in significant resistance to passive or active stretch and limited ROM. -Designation by location- Contractures are described as the side of the joint that has the tissue tightness. ***Contractures develop when normally elastic tissues such as muscles or tendons are replaced by inelastic tissues (fibrosis).

lengthened position (immobilization)

-the application of a series of positional casts (serial casts) -use of a dynamic orthosis to stretch a long-standing contracture and increase ROM. ***suggests myofibrillogenesis= an increase in sarcomeres, may be relatively permanent if the newly gained length is used on a regular basis in functional activities. -minimum time immobilized for this to happen is unknown

dynamic flexibility

-the extent to which an active muscle contraction can rotate a joint through its available ROM. -depends on the ability of a muscle to contract through the ROM -depends on the degree and quality of tissue extensibility

Myostatic (muscle) contracture

-the musculotendinous unit has adaptively shortened and there is a significant loss of ROM, there is no specific muscle pathology present, caused by immobilization and without tissue pathology -may be a reduction in the number of sarcomere units in series, there is no decrease in individual sarcomere length. -can be resolved in a relatively short time with stretching exercises. -induced by changes in muscular factors, including muscles, tendons, and fascia. EX: patient in a cast, contracture from short term immobilization.

Arthrogenic (joint) contracture

-the result of intra-articular pathology -changes may include adhesions, synovial proliferation, joint effusion, irregularities in articular cartilage, or osteophyte formation. -induced by changes in articular factors, including bones, cartilage, joint capsules, and ligament -RA/OA can contribute ***When joint immobilization is prolonged (more than 2-4 weeks), this contracture becomes the primary determinant of the severity of contracture, mainly because of changes in the joint capsule

Examine and evaluate patient prior to stretching

1. Baseline joint measurements 2. Posture analysis 3. Review medical history/medications 4. Determine what structure have hypomobility 5. Assess strength 6. Consider goals/outcomes 7.

Hold-relax w/ agonist contraction HR-AC (PNF)

1. move the limb to the point that tissue resistance is felt in the rangelimiting target muscle; 2. then have the patient perform a resisted, prestretch isometric contraction of the rangelimiting muscle, 3. followed by voluntary relaxation of that muscle 4. And an immediate concentric contraction of the muscle opposite the range-limiting muscle.

Hold-relax HR (PNF)

1. muscle is lengthened to the point of tissue resistance or to the extent that is comfortable for the patient. 2. patient then actively performs a prestretch, end-range, isometric contraction (held for about 5 seconds) of the range-limiting target muscle against manual resistance applied by the clinician. 3. followed by voluntary relaxation of the target muscle. 4. The limb is then passively moved by the clinician into the new range as the range-limiting muscle is elongated. ***appear to make passive elongation of muscles more comfortable for a patient than manual passive stretching.

Effects of injury (changes in collagen affecting stress-strain curve)

1. newly synthesized type III collagen bridging the injury site (weaker than mature type 1 collagen) 2. Remodeling progress and mature to type 1 3. Depending on size of structure and magnitude of rupture, remodeling begins 3 weeks post surgery and continues for several months to a year.

intrafusal fibers (part of muscle spindle)

2 types: -nuclear bag fibers= (type Ia) afferent endings, sense and cause muscle to respond to both quick and sustained stretch. -nuclear chain fibers= (type II) afferents are sensitive only to sustained stretch. 2 ways to stimulate these sensory afferents by means of stretch: -one is by overall lengthening of the muscle -the other is by contraction of the intrafusal muscle fibers via the gamma efferent neural pathways.

Biofeedback

A patient, with proper instruction, can monitor and learn to reduce the amount of muscle tension through biofeedback instrumentation, using audio/visual cues from instrumentation. also be used to help a patient increase voluntary muscle activation

ballistic stretching (speed of stretch)

A rapid, forceful intermittent stretch—that is, a high-velocity and high-intensity stretch—is commonly called ballistic stretching. -preparatory to an activity. -thought to cause greater trauma to stretched tissues and greater residual muscle soreness than static stretching. -safely increases ROM in young, healthy subjects participating in a conditioning program -not recommended for elderly or sedentary individuals or patients with musculoskeletal pathology or chronic contractures.

Cyclic stretch (duration of stretch) (*safest)

A relatively short-duration stretch force that is repeatedly but gradually applied, released, and then reapplied multiple times during a single treatment session is described as a cyclic (intermittent) stretch. -end range stretch force, slow velocity, controlled manner, and low intensity. -more comfortable than static stretch/heat production may be related to tissues stretching more easily. -In practice, this determination is often based on the patient's response to stretching. Although the evidence is limited, cyclic loading has been shown to increase flexibility as effectively or more effectively than static stretching.

Soft Tissue Mobilization/Manipulation Techniques

Although these techniques involve various forms of deep massage, the primary purpose is not relaxation but to increase the mobility of adherent or shortened connective tissues including fascia, tendons, and ligaments. With myofascial massage, stretch forces are applied across fascial planes or between muscle and septae. With friction massage, deep circular or cross-fiber (perpendicular to tissue fiber orientation) massage is applied to break up adhesions or minimize rough surfaces between tendons and their synovial sheaths. Instrument-assisted soft tissue mobilization (Graston) uses uses specially crafted tools to release fascial restrictions and scar tissue.

Relaxation training

Autogenic training= involves conscious relaxation through autosuggestion and a progression of exercises as well as meditation. Progressive relaxation= uses systematic, distal-to-proximal progression of voluntary contraction and relaxation of muscles. (Isometric contractions throughout the body, head to toe) Awareness through movement= patient works through stretch and consciously makes minor adjustments based on feel, deep breathing, conscious relaxation procedures, and self-massage

Self-stretch

Characteristic: -done independently by the patient after careful instruction and supervised practice. -often an integral component of a HEP -necessary for long-term self-management of many musculoskeletal and neuromuscular disorders. Effectiveness: -patient must perform self-stretching procedures correctly and safely (education is very important) Application: -Static stretching for a 30- to 60-second duration per repetition is considered the safest type of self-stretching. -self ROM/PNF/low intensity active stretching (dynamic ROM)

mechanical stretching

Characteristics: -Mechanical stretching devices apply a very low-intensity stretch force over a prolonged period of time to create relatively permanent lengthening of soft tissues, presumably due to plastic deformation. -equipment can stretch shortened tissues and increase ROM. -provide either a constant load with variable displacement or constant displacement with variable loads. Effectiveness: -The term permanent may mean that length increases were maintained for as little as a few days or a week after discontinuing use of a stretching device, while long-term follow-up may indicate that tissues have returned to their shortened state. -mechanical stretching listed below has been shown to be effective, particularly in reducing long-standing contractures: -cuff weight (a few pounds) -joint active systems= adjustable orthosis, patient can control/adjust setting during session -orthotics w/ preset load that remain constant Application: -responsibility of a therapist to recommend the type of stretching device that is most suitable to the patient -fabrication of serial casts or orthoses used for mechanical stretching. -Duration: Mechanical stretch durations reported in the literature range from 15 to 30 minutes to as long as 8 to 10 hours per session or continuous throughout the day except for time out of the device for hygiene and exercise.

Mechanical behavior of non-contractile tissue

Collagen fibers= Those tissues that withstand high tensile loads are high in collagen fibers; PGs= those that withstand greater compressive loads have greater concentrations of PGs. *composition of the tissue changes when the loading environment changes.

Grade III microfailure (failure)

Complete rupture or tissue failure after deformation beyond the plastic range.

Mechanical properties of muscle tissue

Contractile= contractility and irritability (a muscles response to stimulus), sarcomere is the contractile unit of the myofibril= muscles ability to contract and relax. Non-contractile= endomysium, perimysium, epimysium, tissue adhesions within and between the collagen fibers of these structural tissues can resist and restrict movement and result in joint contracture.

designation of a contracture by location

Contractures are described as the side of the joint that has the tissue tightness. If the tightness is on the flexion side of the flexion/extension joint axis, it is called a flexion contracture. EX: patient with shortened elbow flexors who cannot fully extend the elbow, have an elbow flexion contracture.

Stabilization

Fixation of a bony segment that has an attachment of the muscle to be stretched. -Without stabilization, the attachment sites are free to move with the tissue, reducing the ability to effectively maximize the origin-insertion distance. -therapist stretch= stabilize proximal, move distal -self-stretching= stabilize distal, move proximal *chair or doorframe can be used for stabilization

Mode of stretch

Form or manner in which the stretch force is applied (static, ballistic, or cyclic), degree of patient participation (passive, assisted, or active), or the source of the stretch force (manual, mechanical, or self). *it is imperative that the shortened muscle remains relaxed and that the restricted connective tissues yield as easily as possible to the stretch. -stretching should be preceded by either low-intensity active exercise or therapeutic heat to warm the tissues that are to be lengthened.

Manual or Mechanical/Passive or Assisted (stretching)

Intervention to increase mobility of soft tissues -End range stretch force will elongate muscle/CT when rotate beyond available ROM. -force can be applied by manual contact/mechanical device and can be sustained or intermittent. -relaxed as possible during the stretch= passive stretching. -patient assists in moving the joint through a greater range= assisted stretching.

Joint mobilization/manipulation

Intervention to increase mobility of soft tissues -applied to joint structures by the clinician to modulate pain and treat joint impairments that limit ROM. -adjusting joint to cause movement.

Neural Tissue Mobilization (Neuromeningeal Mobilization)

Intervention to increase mobility of soft tissues -improve or restore nerve tissue mobility. -become restricted by tissue adhesions or scar tissue following trauma or surgical procedures. -the neural pathway is mobilized through selective procedures. These techniques are described in Chapter 13.

Muscle Energy Technique

Intervention to increase mobility of soft tissues -procedures employ voluntary muscle contractions by the patient in a precisely controlled direction and intensity against a counterforce applied by the practitioner -Wagner, "isometric contractions to move bone." -principles of neuromuscular inhibition are incorporated into this approach, another term used to describe these techniques is postisometric relaxation.

Neuromuscular Facilitation and Inhibition Techniques

Intervention to increase mobility of soft tissues -reflexively decreasing tension in shortened muscles prior to or during the stretch. -proprioceptive neuromuscular facilitation (PNF)/PNF stretching, -active inhibition, -active stretching, -facilitated stretching

self stretching

Intervention to increase mobility of soft tissues -stretching exercise that is carried out independently by a patient after instruction and supervision by a therapist -forces are applied by the patient at the end of available ROM for the purpose of elongating hypomobile soft tissues. -not the same a flexibility exercises (healthy patient w/o MOB impairments)

Soft Tissue Mobilization/Manipulation

Intervention to increase mobility of soft tissues Many techniques; -including friction massage, -myofascial release, -acupressure, -trigger point therapy, ***specific techniques are not described in this textbook

Duration of stretch (static/cyclic)

Length of time the stretch force is applied during a stretch cycle. -time is more important then force. -Despite many studies over several decades, there is lack of agreement on the ideal combination of single stretch duration and number of stretch repetitions that leads to the greatest and most sustained stretch-induced gains in ROM or reduction of muscle stiffness.

Massage for relaxation

Local muscle/self massage relaxation can be enhanced by massage, particularly with light or deep stroking techniques. Because massage has been shown to increase circulation to muscles and decrease muscle spasm, it can be a useful adjunct to stretching exercises.

Intensity of stretch (patient tolerance)

Magnitude of the stretch force applied. -stretching should be applied at a low intensity by means of a low load. -more comfortable for the patient & minimizes voluntary or involuntary muscle guarding, enabling the patient to remain relaxed or assist with the stretching maneuver. -results in optimal rates of improvement in ROM without exposing tissues, possibly weakened by immobilization, to excessive loads and potential injury. -been shown to elongate dense connective tissue, a significant component of chronic contractures, more effectively and with less soft tissue damage and post-exercise soreness than a high-intensity stretch.

afferent neurons

Nerve cells that carry impulses towards the central nervous system

efferent neurons

Nerve cells that conduct impulses away from the central nervous system

Common errors and potential problems (with mass market stretching programs)

Nonselective or poorly balanced stretching activities. Insufficient warm-up.= tissue couple be cold Ineffective stabilization.=need to have proper alignment Use of ballistic stretching.= could increase soreness/soft tissue injuries Excessive intensity.= progress gradually Abnormal biomechanics.= could place strain on other tissues Insufficient information about age-related differences.= hypomobilty in older adults

Frequency of stretch (as much a possible)

Number of stretching sessions per day or per week. -Frequency typically ranges from 2-5 sessions per week with time between sessions as needed for tissue healing and to minimize post-exercise soreness. -The correct balance between collagen tissue microfailure and subsequent repair is needed to allow an increase in soft tissue lengthening. -if there is progressive loss of ROM over time rather than a gain in range, continued low-grade inflammation from repetitive stress may be causing excessive collagen formation and hypertrophic scarring.

Alignment

Positioning a limb or the body such that the stretch force is directed to the appropriate muscle group. -Alignment influences the baseline amount of tension present in soft tissue and consequently affects the available joint ROM.

Speed of stretch (slow/ballistic/high-velocity)

Rate of initial application of the stretch force. -A slowly applied stretch is less likely to increase tensile stresses on connective tissues/to activate the stretch reflex. -also moderates the viscoelastic effects of connective tissue, making them more compliant. -easier for the therapist or patient to control making it safer than a highvelocity stretch.

Joint Traction or Oscillation

Slight manual distraction of joint surfaces prior to stretching a muscle-tendon unit can be used to inhibit joint pain and muscle spasm around a joint. Pendular motions of a joint use the weight of the limb to distract the joint surfaces and simultaneously oscillate and relax the limb. The joint may be further distracted by adding a 1- or 2-lb weight to the extremity, which causes a stretch force on joint tissues.

gamma motor neurons (part of muscle spindle)

Small-diameter motor neurons, innervate the contractile polar regions of intrafusal muscle fibers and adjust the sensitivity of muscle spindles to detect length changes.

Types of stress (forces on CT)

Tension= the resistance to a force applied in a manner that will lengthen the tissue. Compression= resistance to a force applied in a manner that approximates tissue. Weight bearing through a joint will produce compression stresses. Shear= resistance to two or more forces that are applied in opposing directions.

Agonist contraction AC (PNF) (Dynamic ROM/DROM/active stretching)

The "agonist" in this case refers to the muscle opposite the range-limiting target muscle, while the "antagonist" refers to the range-limiting muscle. 1. the patient concentrically contracts (shortens) the muscle opposite the range-limiting muscle and then holds the end-range position for at least several seconds. ***The movement of the limb is controlled independently by the patient and is deliberate and slow, not ballistic. -especially effective when significant antagonist muscle guarding restricts muscle lengthening and joint movement but is less effective in reducing chronic contractures. -also useful when the patient cannot generate a strong, pain-free contraction of the range-limiting muscle -useful for initiating neuromuscular control in newly gained joint ROM to re-establish dynamic flexibility. -least effective if a patient has close to normal flexibility.

Use of Increased Mobility for Functional Activities

The most effective means of achieving permanent increases in ROM and reducing functional limitations is to integrate functional activities that use the newly gained range on a regular basis into the stretching program.

Heat

as intramuscular temperature increases, the extensibility of contractile and noncontractile soft tissues likewise increases. In addition, as the temperature of muscle increases, the amount of force required and the time the stretch force must be applied decrease. -tissues relax -less muscle guarding -patient comfort -hot packs/paraffin -ultrasound or shortwave diathermy -Low-intensity, active exercises

Manual stretch (mode)

characteristics: -the clinician or caregiver applies an external force that lengthens the targeted tissue beyond the point of tissue resistance. -can be performed passively, with assistance from the patient, or even independently by the patient. -employs a controlled, static stretch applied at an intensity consistent with the patient's comfort level. It is held for 15 to 60 seconds and repeated for at least several repetitions. -intensity is increased as tolerated Effectiveness: -for increasing tissue extensibility is debatable. Application: -most appropriate in the early stages of a stretching program -if a patient lacks neuromuscular control passive manual stretching by the therapist or caregiver is appropriate -adequate neuromuscular control of the body segment to be stretched, it is often helpful for patient to assist -patient concentrically contracts the muscle opposite the target muscle to assist with joint movement, the target muscle tends to relax reflexively and allow elongation (PNF).

Self-stretching progression

designed to improve dynamic flexibility using a transition from static stretching to dynamic stretching and then to ballistic stretching. *Static stretching → Slow, short end-range stretching → Slow, full-range stretching → Fast, short end-range stretching → Fast, full-range stretching.

Muscle Extensibility

improvement attributed to stretching procedures is more likely due to tensile stresses placed on the viscoelastic, noncontractile connective tissue in and around muscle than to inhibition (reflexive relaxation) of the contractile elements of muscle.

Alpha motor neurons (part of muscle spindle)

innervate extrafusal fibers.

Static Stretch (duration of stretch)

is a commonly used method of stretching in which soft tissues are elongated just beyond the point of tissue resistance and then held in the lengthened position with a sustained stretch force over a period of time. *median duration 30 seconds -well accepted as an effective method to increase flexibility and ROM -considered safer than ballistic

Neurophysiological Properties of Skeletal Muscle

mechanoreceptors (afferent)= two sensory organs of muscle-tendon units, muscle spindle/Golgi tendon organ (GTO), convey information to CNS about the physical environment within the muscle-tendon unit.

Hypomobility

refers to decreased mobility or restricted motion at a single joint or series of joints Prolonged immobilization: extrinsic factors ■ Casts and orthotics ■ Skeletal traction Prolonged immobilization: intrinsic factors ■ Pain ■ Joint inflammation and effusion ■ Muscle, tendon, or fascial disorders ■ Skin disorders ■ Bony block ■ Vascular disorders -Sedentary lifestyle and habitual faulty or asymmetrical postures -Paralysis, tonal abnormalities, and muscle imbalances -Postural malalignment: congenital or acquired

reciprocal inhibition (part of stretch reflex)

reflex phenomenon that prevents muscles from working against each other by inhibiting the antagonist *only documented in animal studies.

Static Progressive Stretch (most effective)

that characterizes how static stretching is applied for maximum effectiveness. -The shortened soft tissues are held in a comfortably lengthened position until a degree of relaxation is felt by the patient or therapist. Then the shortened tissues are incrementally lengthened even further and again held in the new end-range position for an additional duration of time.

Autogenic inhibition (Neurophysiological Response of Muscle to Stretch)

the GTO has an inhibitory effect on the level of muscle tension in the muscle-tendon unit in which it lies, particularly if the stretch force is prolonged. -low-intensity, slow stretch force is applied to muscle, the stretch reflex is less likely to be activated as the GTO fires and inhibits tension in the muscle, allowing the parallel elastic component (the sarcomeres) of the muscle to remain relaxed and to lengthen.

contraction (not the same as contracture)

the process of active tension developing in a muscle during shortening or lengthening

Periarticular (CT) contracture

when CTs that cross or attach to a joint or the joint capsule lose mobility and restrict arthrokinematic motion -Trauma to areas can cause damage to CT.

Contraindications to Stretching

■ A bony block limits joint motion. ■ There was a recent fracture, and bony union is incomplete. ■ There is evidence of an acute inflammatory or infectious process (heat and swelling), or soft tissue healing could be disrupted in the restricted tissues and surrounding region. ■ There is sharp, acute pain with joint movement or muscle elongation. ■ A hematoma or other indication of tissue trauma is observed. ■ Joint hypermobility already exists. ■ Shortened soft tissues provide necessary joint stability in lieu of normal structural stability or neuromuscular control. ■ Shortened soft tissues enable a patient with paralysis or severe muscle weakness to perform specific functional skills otherwise not possible.

Determinants of Stretching Interventions (BOX 4.3 pg. 95)

■ Alignment ■ Stabilization ■ Intensity of stretch ■ Duration of stretch ■ Speed of stretch ■ Frequency of stretch ■ Mode of stretch

Indications for Stretching

■ ROM is limited because soft tissues have lost their extensibility as the result of adhesions, contractures, and scar tissue formation, causing activity limitations or participation restrictions. ■ Restricted motion may lead to structural deformities that are otherwise preventable. ■ Muscle weakness and shortening of opposing tissue have led to limited ROM. ■ May be a component of a total fitness or sport-specific conditioning program designed to prevent or reduce the risk of musculoskeletal injuries. ■ May be used prior to and after vigorous exercise.