is a small space (subacromial) between the head of the upper arm bone (humerus)
and the acromion (a bony projection from the top of the shoulder blade) that the
rotator cuff passes through.
Raising the arm overhead normally
causes the head of the humerus to rise upwards slightly within
the subacromial space. This naturally will narrow the space between the head
of the humerus and the acromion causing compression of the rotator cuff tendons
and bursa. As we age, the blood supply to the rotator cuff diminishes
making the rotator cuff more susceptible to injury/damage. If the rotator
cuff or bursa becomes inflamed with repetitive compression the subacromial space
becomes even smaller with overhead movements of the arm thus causing more
compression. This may lead to impingement syndrome.
Bursitis (inflammation of a bursa) often occurs
along with tendonitis and/or impingement syndrome.
bursa is a sac (containing a small amount of fluid) located between the tendon
and bone that helps the moving parts of a joint glide smoothly. There is a bursa
between the supraspinatus (a rotator cuff tendon) and acromion (roof of shoulder
Occasionally, calcium deposits or bone spurs may be
present within the rotator cuff tendon(s) or the underside of the acromion.
This can also cause impingement syndrome.
(such as swimming, tennis, painting overhead, etc.) that involve repetitive
overhead arm movement can cause repeated contact and friction between the
rotator cuff tendons and the undersurface of the acromion.
Symptoms of Shoulder Impingement
Symptoms usually start gradually
in the top-outer portion of the shoulder. There may be mild pain all the time,
with sudden pain when reaching overhead and pain when lowering the arm from an
overhead position. There may be weakness of the shoulder. If not treated, the
condition may worsen.
Treatment of Shoulder I
Strengthening the rotator cuff (especially the
supraspinatus) and the shoulder blade muscles helps prevent the humerus from
rising excessively with overhead movement of the arm. Proper posture of
the shoulder at rest and with activity is very important as “slouching” can
narrow the subacromial space; resulting in more impingement.
Stiffness of the shoulder joint capsule is common in
impingement syndrome which responds very well to manual stretching.
Ultrasound (sound wave therapy) can help to increase circulation to the tendons
and help reduce swelling. Taping techniques are also beneficial in helping
to center the humeral head within the socket which may diminish the impingement
of the rotator cuff tendons.
What Should You Do?
If your pain has been
persisting for several months you should see you family physician for an
assessment and he/she will order any diagnostic tests (x-rays, ultrasound) if
appropriate. You should see a therapist as soon as possible to determine
the proper course of active treatment that is best for you. Your therapist
will be able to give you home exercises (stretches and strengthening exercises)
that are right for you and he/she may also manually stretch your shoulder to
restore mobility to the joint.