The shoulder is the most mobile joint in the entire body. The shoulder joint is a ball and socket joint where the head of the humerus bone rests inside the shallow cavity of the scapula, or shoulder blade. This joint is surrounded by a grouping of muscles and tendons that are intended to stabilize and allow movement of the arm with the shoulder blade. Ball and socket joints allow for maximal range of motion in multiple directions.Due to its laxity and mobility, the shoulder joint is less stable and thus, more prone to injury.
There can be many different types of injury to the shoulder; some affecting the tendons, muscles, the bones themselves or a combination of all three. Four common shoulder injuries are Frozen Shoulder, Rotator Cuff Injuries, Impingement Syndrome and Dislocation/Subluxation. The causes, symptoms and treatments for each differ depending on the exact location of the injury and what elements are disturbed.
Frozen Shoulder (Adhesive Capsulitis)
Frozen shoulder is a common term referring to adhesive capsulitis. Adhesive capsulitis is when movement of the shoulder joint becomes restricted in all directions due to capsular shrinking.Some signs that frozen shoulder may exist include severe pain during movement, muscle spasm, weakness, numbness or a tingling sensation close to the joint itself or radiating to the neck or arm. Although referred to as ‘frozen shoulder’ the shoulder doesn’t actually freeze. Frozen shoulder can be brought on by other shoulder injuries, and with the pain of those, the shoulder is naturally kept immobile and along with any scar tissue that may have developed stiffness will occur. Frozen shoulder can usually be easily diagnosed when symptoms are verbalized and many people with frozen shoulder do, in fact re-gain full mobility and strength of the shoulder with proper assisted therapies.
Rotator Cuff Injuries
The rotator cuff is made up of four different muscles, which come together and converge to form the rotator cuff tendon. Rotator cuff injuries refer to the strain or damage of the muscle/tendon grouping. This type of shoulder injury can be brought on by trauma (bracing a fall or impact during a motor vehicle accident), repetitive over-head activities or due to the natural effects of aging. The fibres of the muscles and tendons can stretch, tear partially or even completely. Pain and muscle spasm can occur and in turn, limit the range of motion and make simple every-day tasks much more difficult. In turn, weakening of muscles and tendons, the slight adjustments of the humerus can no longer take place creating rigid movement and more pain. Scar tissue can also collect within the joint as a result of tearing, thus creating much discomfort or limitations during movement.
Impingement syndrome occurs when the tendons of the rotator cuff become impinged, or interrupted when passing through the naturally narrow space within the shoulder joint. Impingement syndrome is also a symptom of other shoulder injuries and can exist due to a dislocation, subluxation, scapula dysfunction, rotator cuff injury or even bone spurs. These conditions reduce the naturally narrow space and thus irritate and inflame the tendons. Movement in any direction may be limited and painful as well.
Dislocation / Subluxation
A dislocation (or luxation) of the shoulder is when the head of the humerus separates from the socket of the shoulder blade; a complete separation. Subluxation refers to only a partial dislocation where the bones in the joint are resting together but out of alignment and this creates much friction during movement. Most people who suffer from a dislocated shoulder can regain full range of motion within four weeks and for some, the injury may hinder full recovery and leave the supporting muscles and tendons weaker and the ligaments permanently stretched and thus, more prone to re-injury.
Depending on the severity, treatments for these conditions vary between active and passive therapies to reconstructive surgeries. Active therapy aims to enhance and restore functional ability and quality of life.
Examples of this include stretching and strengthening exercises as well as low-impact aerobic conditioning. Passive therapy, on the other hand, is treatment given by a Physiotherapist Athletic Therapist or Chiropractor. Examples include soft tissue therapy, massage, heat and cold therapy, ultrasound and electrotherapy. Assisted rehabilitation is essential in all cases to re-build strength and stability of the joint.