Rehabilitative Exercise for Shoulder Injuries

Exercise is perhaps the most understood and misused form of functional rehabilitation. When applied correctly, it is the best insurance for prevention of an injury or disability over any treatment available. Taking into consideration the type of injury; age; medical history; mental attitude; and type of vocation, any patient can benefit from rehabilitative exercise.

Rehabilitative exercise must be personalized to fit the needs of each individual's cognitive and psychosocial motivation; understanding the perception of pain (and types of pain); goal-setting and limitations; and integrating the patient back into productive work and social activity. When patients understand their active role in recovery, they tend to progress at a faster rate even if a monetary gain is expected. By taking an active role in recovery, the patient benefits by feeling in control of his or her health.

Types of Shoulder Injuries

Overuse Injuries

Stress fractures; compartment syndromes; sprains; strains; tendonitis; tenosynovitis; and bursitis are common soft tissue overuse injuries.

Impingement

1. A small acromid arch due to heredity.
2. Decreased space between the acromion and humerus due to hypertrophy in athletes such as weightlifters, baseball pitchers, golfers and quarterbacks.
3. Subacromial bursitis and overuse tendonitis.

Rotator Cuff Tears

The supraspinatus is the most common muscle involved and is most often atrophied. There are four stages of rotator cuff lesions:

1. No defects: symptoms include edema; inflammation; and temporary thickening of bursa and rotator cuff.
2. No defects: symptoms include fiber disassociation and permanent thickening of the bursa and rotator cuff with scar formation.
3. Defect of 1cm or less: symptoms include possible partial tear and permanent thickening of the bursa and rotator cuff with scar formation.
4. Defect larger than 1cm: symptoms include permanent thickening of the bursa and rotator cuff with scarring.

Rehabilitative Exercise

Rest, ice, compression and elevation (RICE) should be used when needed for pain, inflammation and edema as needed for acute or chronic injuries. Stretching range of motion exercises should be maintained at a level that does not increase pain, edema or inflammation. Weight-bearing exercise may begin when full range of motion is attained.

Stretching

1. Dynamic - movement of a body part against gravity to increase range and speed in a fluid motion. The muscle agonists tense while the antagonists are stretched; flexibility is increased in proportion to the tendon of the contracted muscle and relaxation of the muscle being extended.
2. Ballistic - the use of momentum to increase range of motion by force.
3. Static passive - relaxing into a stretch, letting gravity or weight hold the position.
4. Static active - tensing the muscle agonist. Isotonic contraction. Relaxation of the antagonists occurs by reciprocal inhibition of the agonist tendon being held.
5. Isometric - tensing the muscle without joint movement. Stretch the muscle, wait and tense the muscle for five seconds. Stretch the muscle further, and tense the muscle again. Use this technique for up to five repetitions, holding the last stretch for no more than 30 seconds.

Theory of Mechanism

Altering the regulated tension of the contractile filaments of the muscle fibers enables the patient to increase range of motion without compromising ligaments or tendons. Muscle fibers are innervated at the neuromuscular junction and the muscle length; muscle tension is regulated in the spinal cord by reciprocal inhibition from motor neuron alpha, which controls contraction (length), and motor neuron gamma, which controls tension. Muscle fibers; stretch receptors; sensory neurons; and motor neurons alpha and gamma make up the gamma loop.

Golgi organs and Renshaw cells also regulate tension. Golgi organs relax muscles at the tendon by firing in relation to contraction from motor neuron alpha relieving excessive contraction or stretching. Renshaw cells inhibit the motor neuron gamma regulating the strength of contraction.

Voluntary control of muscle tendon can be influenced and altered by the pyramidal tract. This originates in the cerebral cortex (sensory, voluntary), which synapses with motor neurons alpha and gamma; associated neurons from the proprioceptive cerebellar system (kinesthetic coordination; balance; tonus); and extra pyramidal tract (fine voluntary movement, postural and locomotive). This influence is augmented by the cerebellum, hippocampus, amygdala, and septal area connection (emotion).