5.4 Common Injuries and Disorder of Muscles
A. Strains
1. Muscle strain occurs when a muscle is stretched beyond its usual limits.
- flexibility in individuals matters (some people have “tighter” muscles
crossing joints than others)
- another factor in muscle strains is the speed of which a muscle is stretched
(athletes running, accelerating and changing direction all at the same time)
2. Classification of Strains
Grade I – (mild) tightness in muscle day after injury
Grade II – (moderate) pain, partial muscle tear, weakness, temp. loss of use
Grade III – (severe) tearing of muscle, loss of function, internal bleeding and
swelling
3. Hamstring strains are frequent injuries in athletes, one-third of all hamstring
strains reoccur within one year of returning to the sport.
B. Contusions
1. Bruise or bleeding within a muscle resulting from an impact.
2. myositis ossificans – calcium deposits in a muscle from repeated impact
C. Cramps
1. Moderate to severe muscle spasms causing pain
2. Many causes: electrolyte imbalance, deficiency in magnesium, calcium,
potassium or dehydration.
D. Delayed-Onset Muscle Soreness (DOMS)
1. Muscle soreness commonly occurs 24 – 72 hours after unaccustomed use
2. Multiple microscopic tears in muscle tissue resulting in: inflammation, pain,
swelling and stiffness.
E. Tendinitis and Tendinosis
1. Tendinitis – inflammation of a tendon, swelling and pain
- caused by acute and chronic overuse, disease
- common areas are elbow, shoulder, wrist and Achilles tendon
- treatment includes rest, cold and heat therapy, ibuprofen can reduce
inflammation and pain
2. Tendinosis – untreated chronic tendinitis
- leads to degeneration of the tendon, tears, weakness, possible rupture
- recover takes months with minimal use
F. Rotational Injuries of the Shoulder
1. caused by repetitive forceful overhead motion (swimming, tennis, pitching,
spiking in volleyball)
2. treatment: rest, ice, surgical repair if necessary
G. Overuse Injuries of the Elbow
1. Epicondylitis – inflammation and micro tearing of muscle tendons in elbow
- Lateral epicondylitis – 30-40% of tennis players = tennis elbow,
hammering, fencing, swimming
- Medial epicondylitis – pitching, golfing; known as Little Leaguer’s elbow
H. Shin Splints - pain to the medial lower leg
1. cause by overuse: runners (especially on hard surfaces or uphill), dancers
2. micro damage or inflammation to the tendons or periosteum of the tibia
I. Whiplash Injuries – injuries to the neck (cervical vertebrae)
1. abnormal motion of the neck, along with rapid, forceful contractions as
neuromuscular system attempts to stabilize and protect the spine
2. typically caused by car accident
3. pain extends down the shoulders, arms and hands, includes headache
J. Muscular Dystrophy (MD)
1. Group of inherited diseases characterized by progressive muscle weakness
- some MDs only affect certain muscle groups, others affect all
- some MDs begin in childhood, others in adulthood
2. No known cures, therapy to control the symptoms
- some symptoms shorten life span, others cause little or no disability
K. Hernia
1. Portion of the abdominal cavity lining protrudes through abdominal muscles
2. Can be present at birth, caused by heavy lifting (pressure in abdominal cavity)
3. Hernia can strangle the tissue (cut off blood supply) that protrudes – immediate
surgery is needed.
4. Small hernias can have no symptoms and may need no treatment.
Grade III muscle strains