For those afflicted by the condition, frozen shoulder (Adhesive Capsulitis) can be extremely disruptive to life. Pain with movement, limited ability to lift or move the arm, and pain when lying down will interfere with most activities, even getting a good night’s sleep. Particularly frustrating is the prognosis: it will take at least eighteen months to resolve, even with treatment.
It is believed that the joint capsule becomes inflamed and then builds scar tissue, resulting in pain with use and limiting range of motion. Scar tissue formation explains the slow response to traditional treatment consisting of mobility exercises, heat/ice, pain and anti-inflammatory medication, injection therapy, and in severe cases, surgical procedures.
The shoulder is a complex structure. The joint itself is made of the round head of the humerus bone meeting a disc shaped part of the shoulder blade (glenoid fossa of the scapula). It is covered by the joint capsule, which is made up of fibrous ligaments. There are also a number of tendon attachments near the joint including the rotator cuff muscles, pectoralis major and minor, biceps, triceps and others. Just above the shoulder joint is a much less mobile joint (AC joint) between the acromion process of the shoulder blade and the clavicle (collarbone). The deltoid muscles attach to these bones and then insert onto the humerus about half way down. There are also arteries, veins, and nerves, which travel in close proximity of the joint, providing bloodflow and nerve input to and from the joint itself, as well the muscles that move it.
All the bones, ligaments, muscles, tendons, arteries, veins, nerves of the body are covered by fascia. This fascia not only blankets these structures, it also contains blood vessels and nerves. These nerves are able to sense both strain and pain, and will transmit this information to the spinal cord, where they connect to motor neurons affecting muscles and to neurons of the autonomic nervous system, which affect blood flow, and functions such as digestion, respiration, and heart rate. In response to injury, tissue irritation, or perceived threat, this connection of nerves will create a protective spasm in the muscles surrounding the involved structure(s) and also limit blood flow, which then leads to limited range of motion due to pain as well as swelling in the affected area. The fascia directly overlying the affected structure will be tightened as well. When this protective mechanism has been triggered, it will limit joint mobility, increase tension within the joint capsule, and cause pain when the joint is moved into the restricted range. Even ligaments that support the spine will refer tightness into joints of the extremities when they are in a state of protective spasm. A successful outcome requires treatment to all of the involved structures, not just the two or three obvious ones.