Soft Tissue Changes and

Damages Due to Stroke

Definition of Soft Tissues

How stroke lead to soft tissue changes

Features of stroke

Other factors leading to further soft tissue changes

Clinical Implications

PT interventions

Contents…

What are Soft Tissues?

• Soft tissue refers to tissues that connect, support, or surround other structures and organs of the body.

• Soft tissue includes muscles, tendons, ligaments, fascia, nerves, fibrous tissues, fat, blood vessels, and synovial membranes.

How stroke lead to soft tissue changes..

stroke

ischemia and anoxia of brain tissue

irreversible neural damage.

decreased recruitment of the motor units

results in muscle atrophy

during the recovery, spasticity occurs

How stroke lead to soft tissue changes..

chronically shortened muscle may develop physical changes

further contribute to muscle stiffness.

Process of recovery following stroke-induced hemiplegia1. Flaccidity (immediately after the onset)

- No "voluntary" movements on the affected side can be initiated

2. Spasticity appears - Basic synergy patterns appear- Minimal voluntary movements may be present

3. Patient gains voluntary control over synergies

- Increase in spasticity

4. Some movement patterns out of synergy are mastered (synergy patterns still predominate)

- Decrease in spasticity

Brunnstrom (1966, 1970) and Sawner(1992)

5. If progress continues, more complex movement combinations are learned as the basic synergies lose their dominance over motor acts

- Further decrease in spasticity

6. Disappearance of spasticity - Individual joint movements become possible

and coordination approaches normal

7. Normal function is restored

Positive features

•exaggeration of normal phenomena

•spasticity

Negative features

•decrease in strength

•slowness of movement

•loss of dexterity and coordination

Features of Stroke

Other factors leading to further

soft tissue changes

1. Immobilization in a

Shortened Positiona) Effects on Muscles

Anatomical Changes

up to 40% decrease in the number of sarcomeres. (J. C. Tabary et al, 1972, William & Goldspink 1978) [illustration]

Reduced extensibility (J.C Tabary at al, 1972)

Effects are specific to fiber type. (Gossman et al, 1982) [illustration]

•The absolute and relative numbers of type II fibers increases.

•Accompanied by phagocytosis of type I fibers.

Normal

ShortenedAdaptation

[back]

Biochemical Changes

More pronounced shortened muscles than in lengthened muscles.

Changes in the shortened muscles favor catabolism.

Followed by loss of weight. There is evidence that changes may be specific to muscle fiber types. (Sohar I et al, 1977)

Physiological Changes

1) Passive tension curve shifts to the left. (Tabary et al, 1972)

2) Active tension also decreases. (Gossman et al, 1982)

Passive Tension

b) Effects on Tendons

•Decreased size and amount of collagen fibers Reduces total load tolerance

•Compliance increases due to increased elastic fibers.

•Collagen fibers become thinner and less organized, and cross-links are reduced

•The tendon is less susceptible to immobilization-induced changes.

[CM tipton et al, 1986]

c) Effects on Ligaments

Ligament responds to immobilization at a slower rate

The total collagen mass decreases

strength and stiffness decrease

ligament also shortens

d) Effects on Articular Cartilage

•Decreased loading and motion => degeneration of the articular surface.

• Increased water content, decreased proteoglycans and alters proteoglycan organization.

• Precede softening and fragmentation of chondral surfaces.

•Decreases in cartilage stiffness and thickness make the cartilage more vulnerable to injury.

•Loss of matrix proteoglycan places an increased load on the remaining tissues

•Bony proliferation -> osteophytes formation.

2. Disuse

Accomodation by the use of proximal joints or via unaffected side.

Decreased Loading leads to adaptive shortening of muscles.

Learned Disuse

Secondary soft tissue changes, bring about pain and weakness.

Vicious Cycle

Damages

• Muscle Atrophy

• Decreased ROM

• Decreased Dexterity

• Hygiene

• Balance

PT Interventions

Improving Dexterity

• Constrained Induced Movement Therapy

(Wolf et al 06)

• Correcting PostureThere is a positive relationship between good posture and manual dexterity. (Buffington et al 06)

We can do by giving audio feedback and also use mirrors for visual feedback.

• Task Related Exercises

A study of task related exercise with afferent stimulation, it was shown that even the control group also benefited from the task related exercise.

(McDonnell et al 07)

Tasks like wrist extension against resistance, manipulation of putty and placing objects in boxes.

Improving Range of Motion

1) Positioning• Maintain at-risk muscles ( internalrotators and adductors of the shoulder andlong finger and thumb flexors, plantar

flexors,hip and knee flexors) and soft tissue in alengthen position• To prevent muscle shortening and

increased stiffness.• At least 30 mins a day of positioning the

affected shoulder in ext rotation for stroke patients to reduce contractures. ( Ada L et al, 2004)

2) Serial Casting• Increased joint mobility, reduce

hypertonia and muscle contracture of the limbs increased ROM

• aims to gradually move the limb into a more functional position.

3) PNF Techniques• To enhance both active and passive

range of motion• A combination of passive stretching

and isometrics contractions• Encourage flexibility and

coordination throughout the limb's entire range of motion

Improving Strength1)Task-oriented progressive resistance

strength training• Aim to improve functional performance as well

as to increase muscle strength• Ray – Yau Wang et al (2006) shows significant

improvement of the muscle strength for strong side and paretic side muscle groups.

• Weiss et al suggest that improved rate of task oriented progressive resistance strength training = traditional progressive resistance strength training

• Carl and Shepherd have indicated that transfer is unlikely to occur unless subjects are also practising the task to be learned.

Improving Range of Motion

2) Weight bearing exercises• Allows increased in joint stability and

co-contraction of muscles surrounding the joint.

• Emphasized eccentric control of the muscles

• Aids in muscular recruitment which stimulates functional activities.

• Stroke patients attain significant improvements in knee flexor strength doing weight bearing exercises. ( Dong Koog Noh et al, 2008)

Other factors that may affect the outcome of treatment

• Severity of stroke • Co existing medical problems • Type of stroke• Compliance of pt: post stroke fatigue• Age and pro morbid status of pt

References• Canning et al: Loss of strength contributes more to physical

disability after stroke than loss of dexterity. Clinical Rehabilitation (2004), 18, pp. 300-8

• Wolf et al: Effect of Constraint-Induced Movement Therapy on Upper Extremity Function 3 to 9 Months After Stroke. Journal of the American Medical Association (2006), 296, pp. 2095-2104.

• Buffington et al: Body Position Affects Manual Dexterity. Anesth Analg (2006), 102, pp. 1879-1883

• McDonnell et al : Influence of Combined Afferent Stimulation and Task-Specific Training Following Stroke: A Pilot Randomized Controlled Trial. Neurorehabil Neural Repair (2007), 21, pp. 435–443

• Tabary JC, Tabary C, Tardieu C, et al: Physiological and structural changes in the cat's soleus muscle due to immobilization at different lengths by plaster casts. J. Physiol (1972), 224, pp. 231-244

• Therapeutic exercise: Moving towards function. Carrie M Hall, Lorie Thein Brody. Chap 7.

• Tipton CM et alExperimental studies on the influences of physical activity on ligaments, tendons and joints: a brief review Acta Med Scand Suppl 1986;711: 157-168

• Williams and Goldspink: chnages in sarcomere length and physiological properties ini immobilied muscle J Anat 1978, 127,3 pp. 458-468

Sharman et al : Proprioceptive Neuromuscular Facilitation StretchingMechanisms and Clinical Implications. Sports Med2006 36(11) pp.929-939

Ray-Yau Wang et al : Task –oriented progressive resistance strength training improves muscle strength and functional performance in individuals with stroke. Clinical Rehabilitation 2006;20;pp.860-870

Miller et al: Strength training in spastic hemiparesis: should it be avoided? Neurorehabilitation 9 (1997) pp.17-28

Ada L et al: Thirty minutes of positioning reduces the development of shoulder external rotation contracture after stroke: a randomized controlled trial. Archives Of Physical Medicine And Rehabilitation 2005 Feb; Vol.86(2), pp230/234

Gelber et al : Therapeutics in the management of Spasticity. Neurorehabilitation and Neural Repair, Vol.13, No.1 ,1999

Mortenson et al: The Use of Casts in the Management of Joint Mobility and Hypertonia Following Brain Injury in Adults: A Systematic Review. Physical Threrapy, Vol. 83, No.7,July 2003

Sharman et al : Proprioceptive Neuromuscular Facilitation Stretching Mechanisms and Clinical Implications. Sports Med2006 36(11) pp.929-939Ray-Yau Wang et al : Task –oriented progressive resistance strength training improves muscle strength and functional performance in individuals with stroke. Clinical Rehabilitation 2006;20;pp.860-870Miller et al: Strength training in spastic hemiparesis: should it be avoided? Neurorehabilitation 9 (1997) pp.17-28Ada L et al: Thirty minutes of positioning reduces the development of shoulder external rotation contracture after stroke: a randomized controlled trial. Archives Of Physical Medicine And Rehabilitation 2005 Feb; Vol.86(2), pp230/234Gelber et al : Therapeutics in the management of Spasticity. Neurorehabilitation and Neural Repair, Vol.13, No.1 ,1999Mortenson et al: The Use of Casts in the Management of Joint Mobility and Hypertonia Following Brain Injury in Adults: A Systematic Review. Physical Threrapy, Vol. 83, No.7,July 2003