What is the Rotator Cuff?
The rotator cuff is a group of four muscles and their tendons of insertion
that attach circumferentially around the shoulder joint to the upper
most portion of the upper arm bone called the humerus. The shoulder
joint itself is not a ball and socket joint, but rather the union of
a large "ball" on one side with a shallow "dish"
or saucer like surface attached to the scapula (or shoulder blade).
The rotator cuff couples these structures together, providing both stability
and mobility. Just above the rotator cuff lies a bony "roof"
made up of the upper tip of the shoulder girdle called the acromion
and the joint it makes with the clavicle (collar bone). Irregularities
of these structures or the ligaments that attach to them can contribute
to irritation of the underlying rotator cuff.
Mechanical wear and tear through repetitive overuse, recurrent trauma
or injury, and muscle forces can result in localized injury to the rotator
cuff tendon, which may then become inflamed and painful. Frequently,
the shape of the overlying acromion and acromioclavicular joint may
be prominent in patients with problems of the rotator cuff. This may
be due to the patient's natural anatomy or it may be due to "wear
and tear changes" resulting in formation of "bone spurs"
along the front edge of the undersurface of the acromion and acromioclavicular
joint. The rotator cuff may become squeezed between the humeral
head and these overlying bony prominences as the arm is brought into
elevation, resulting in damage to the rotator cuff through a process
known as "impingement syndrome".
Signs and Symptoms of Rotator Cuff Disorders
Early stages of rotator cuff irritation are associated with some inflammation
of the tendon itself, known as tendinitis. If wear and tear persists
and damage continues, an actual erosion or degeneration of a portion
of the thickness of the rotator cuff may result (either on the outer
surface, the inner surface, or within the substance of the rotator cuff
itself). This has been referred to as a "partial thickness rotator
cuff tear". If the degenerative process continues unchecked, a
complete erosion of a portion of the full thickness of the rotator cuff
may result in what has been termed a "full thickness rotator cuff
tear". With time and persistent damage, this tear may enlarge.
Additionally, the tendon of a portion of the biceps muscle, which enters
the shoulder joint just below the attachment of the rotator cuff, may
also be worn and may rupture as part of this degenerative process. In
some cases after longstanding tears of the rotator cuff have gone untreated,
derangement in shoulder joint mechanics may result in arthritic changes
of the actual shoulder joint known as a "cuff tear arthropathy".
Pain in and around the shoulder region, sometimes with radiation down
the upper arm or across the upper shoulder, especially related to movement
of the shoulder, is the most consistent symptom. Pain with reaching
overhead, reaching back to put an arm in a sleeve or reaching to the
back seat of an automobile, pain with lifting a heavy object or when
rolling onto the shoulder in bed are all common symptoms. Weakness is
also a common complaint with difficulty externally rotating the arm,
lifting objects, performing a sustained overhead activity or performing
a throwing motion.
How are Rotator Cuff Disorders Diagnosed?
A careful history and physical examination by your physician combined
with diagnostic tests such as x-rays and special imaging studies usually
lead to a correct diagnosis.
Common Treatments for Rotator Cuff Disorders
Treatment is based on the degree of severity of the symptoms. The primary
treatment is a combination of rest, anti-inflammatory medication and
rehabilitation progressing from gentle mobility exercises through progressive
endurance and strengthening exercises as tolerated. When this conservative
management fails to relieve symptoms over a prolonged period of time,
surgery may be indicated. The type of surgery depends on the severity
of the symptoms and the extent of the pathology. Frequently in the earlier
stages of rotator cuff disease, arthroscopy can be used to remove offending
bone spurs and arthritic changes and removes some of the inflammatory
tissue. Smaller tears of the rotator cuff may be repaired using arthroscopy
or with a technique combining arthroscopy with minimally invasive open
surgery. Larger rotator cuff tears usually require open reconstruction
and in those cases with endstage arthritic changes of the shoulder,
joint replacement may be indicated.