Shoulder Instability
Recurrent instability of the shoulder (glenohumeral joint) involves the ball of the joint (humeral head) moving out of the socket (glenoid). Instability also includes a magnitude (dislocation or subluxation) and a direction (anterior, posterior, inferior, or multi-directional).
The labrum is the cartilage rim that deepens the socket and is the attachment point for the capsule. The capsule, a spherical 360 degree ligament complex, is the static stabilizer of the shoulder. The next layer includes the rotator cuff tendons, which are the dynamic stabilizers.
When a shoulder becomes unstable, it is often due to trauma or repetitive micro-trauma. This leads to injury of the labrum and capsule and thus instability of the joint. Arthroscopic instability surgery repairs the labrum and capsule to allow for successful rehabilitation. Arthroscopic instability surgery results are similar to those of open surgical techniques but with much less surgical morbidity or side effects.
Labral Tears
When the ball moves out of the center of the socket, a tear or detachment of the labrum occurs.
Symptoms of a labral tear depend on where the tear is located, but may include:
An aching sensation in the shoulder joint
Catching of the shoulder with movement
Repeated pain with specific activities
Diagnostic procedures may include any combination of the following:
Thorough shoulder exam that includes checking for pain, loss of motion, tenderness, or joint looseness.
X-ray to check for fractures in the shoulder.
MRI with or without an arthrogram to assess damage.
Some patients may require diagnostic arthroscopic surgery to identify the exact location and extent of damage.
Bankart Tears
Labral tears that are located toward the lower part of the labrum (inferior glenohumeral ligament) are called Bankart tears or Bankart lesions. A Bankart tear occurs when an individual dislocates a shoulder. As the shoulder pops out of joint, it often tears the labrum, especially in younger patients. A shoulder may be much more susceptible to future dislocations after the first occurrence and subsequent labral tear.
Typical symptoms of a Bankart tear include:
Popping, grinding or shoulder clicking
Apprehension
Decreased range of motion
Pain or aching in the arm and/or shoulder
Weakness in the arm and/or shoulder
Repeat dislocations
A sense of instability or not being able to trust your shoulder (fear it may dislocate again, especially if the arm is placed behind the head)
SLAP Tear
Labral tears are further defined by where on the glenoid the injury occurs. If the injury is on the top of the labrum, it’s called a SLAP (Superior Labral Anterior Posterior) tear. If the injury occurs near the lower portion of the labrum, the injury is called a Bankart lesion or tear.
Shoulder Arthritis
Shoulder arthritis is relatively common. It typically affects patients over 50 years of age and is more common in patients who have a history of prior shoulder injury.
Shoulder arthritis occurs when the smooth cartilage that normally covers the surfaces of the ball (humeral head) and socket (glenoid) is lost. The result is bone-on-bone rubbing between these two joint surfaces, producing pain, stiffness, difficulty sleeping, and the inability to play sports, work, or complete everyday tasks.
Arthritis can strike one or two joints of the shoulder – the acromioclavicular joint or the glenohumeral joint. The acromioclavicular (AC) joint is located where the collarbone (clavicle) meets the tip of the shoulder bone (acromion), while the glenohumeral joint is found at the junction of the upper arm bone (humerus) and the shoulder blade (scapula). Glenohumeral arthritis will affect the shoulder function to a greater degree than AC joint degeneration.
Frozen Shoulder
Frozen shoulder, also known as adhesive capsulitis, is characterized by pain, loss of motion, or stiffness in the shoulder. Affecting about 2 percent of the general population, frozen shoulder most commonly affects patients between the ages of 40 and 60 years. It is more common in women, and a higher predominance in diabetic patients. There is no known cause of frozen shoulder, but the most important indicator of the condition is restriction of movement. This painful loss of motion is a diagnosis of exclusion, as there will be no other pathologic condition that accounts for the motion loss.
The normal course of frozen shoulder as occurring in three stages:
Stage 1: This is the “freezing” stage. The patient develops a slow onset of pain, and as the pain worsens, the shoulder loses motion. This stage may last anywhere from six weeks to twelve months.
Stage 2: The “frozen” stage is marked by a slow improvement in pain, but stiffness remains limiting the shoulder’s range of motion. This stage can last from four months to nine months.
Stage 3: The final stage is the “thawing” stage during which shoulder motion slowly improves. This stage generally lasts between 5 months and 26 months.