The shoulder joint has a large range of movement, and because of this it is potentially unstable.

The rotator cuff muscles stabalise the shoulder joint. But when they cause problems the range of movement of the shoulder is decreased, and the shoulder and arm can become painful.
This is often called a Frozen Shoulder.
There are 4 muscles that control the Shoulder Joint:
- The Subscapularis
- The Infraspinatus
- The Supraspinatus
- Terres Minor
When one of these muscles shortens, the other muscles also shorten to keep the shoulder joint balanced.
It is similar to putting up a tent - when some one pulls a guy rope to tight and then tightens the other guy ropes to balance the tent. Rather than loosening the original "tight" guy rope at the start.
To help a Frozen Shoulder it is important to treat all the muscles, relax and lengthen them. Then full range of movement starts to return to the Shoulder Joint.
Treatment of a Frozen Shoulder uses a combination of
Osteopathy,
Massage or
Acupuncture.