The rotator cuff consists of four muscles that help to control
the head of upper arm bone (humerus) in the socket (glenoid
Inflammation of any one of these muscles is considered
rotator cuff tendonitis, which can limit motion
to the shoulder joint.
Rotator cuff tendonitis is typically caused from overuse and or
A rotator cuff tear is usually described as
acute or chronic, partial or full thickness. Rotator cuff tears
can occur due to trauma or can result over time.
Acute ruptures are usually seen in individuals younger than 40.
Young athletes typically need surgery to repair the injured
tendon, as pain and loss of motion are too debilitating for
One of the most common labral tears is called a
SLAP lesion (superior labrum, anterior to posterior).
A SLAP lesion is an injury to the superior labrum and biceps
tendon anchor. There are four common types of tears:
Type I: Degeneration and fraying of the labrum
Type II: Detachment of the biceps anchor
Type III: Bucket handle tear with intact
Type IV: A type II or III lesion that extends
into the biceps tendon
Instability is also referred to as MDI
When instability occurs, the head of the upper arm bone (humerus)
can dislocate from the shoulder socket (glenoid cavity) in many
directions with frequent partial dislocations.
A dislocation occurs when the head of the upper
arm bone (humerus) has slipped past the socket (glenoid cavity)
and is dislocated from the joint.
Most dislocations are in front of or behind the socket.
The labrum and supporting muscles have stretched passed normal
range, allowing the the humerus to slide pass the edge of the
A separation refers to an injury to the AC
(acromioclavicular) joint. This is where the collar bone
(clavicle) touches the high point of the shoulder blade
A separation commonly occurs from a blow to the crown of the
shoulder from the ground or another foreign body. There are three
degrees of separations:
First degree: A slight tearing of AC
(acromioclavicular) ligament, not to be confused with the ACL
of the knee
Second degree: A complete tear of AC ligament,
leaving intact the CC (coracoclavicular) ligament that lies
beneath the AC joint
Third degree: A complete tear of both the AC
and CC joint
Bicep tendonitis can inflame the long head of
the biceps tendon as it passes under the highest point of the
Also, an incomplete or partial dislocation of the tendon out of
the bicepital groove of the upper arm bone (humerus) can
predispose an individual to tendonitis.
Pain is usually localized where the biceps tendon connects to the
humerus and rotation of the forearm and hand so the palm faces
forward or upward will be
Typically bursitis of the shoulder refers to an
inflammation of the subacromial bursa due to overuse or overhead
use of the shoulder.
When the subacromial space is inflamed, a rotator cuff
impingement can occur, resulting in the inability to throw or
function above shoulder level.
Thoracic Outlet Syndrome (TOS) refers to
shoulder injuries that can cause pressure to the brachial plexus
and/or subclavian artery.
TOS symptoms include paresthesia - the sensation of prickling,
tingling or creeping on the skin - and coolness of the affected
Individuals experiencing TOS may complain of weakness, feeling
heavy or of feeling easily fatigued.
Impingement typically occurs in athletes who
participate in sports with above-shoulder level action such as
throwing or swimming.
Problems associated with impingement range from subacromial
bursitis, rotator cuff tendonitis and possibly rotator cuff
Symptoms of impingement include:
- Pain and loss of range of motion above shoulder level
- Decreased strength in external rotation