Article > Shoulder > Subacromial Bursitis

Subacromial Bursitis

Bursae are small fluid-filled sacs that function to decrease the friction forces of one anatomical structure moving against another. They occur throughout our bodies in areas of high friction and are typically named according to their location. The subacromial bursa is situated beneath the acromion (part of the shoulder blade that juts out above the shoulder joint) and above the shoulder capsule (comprised of the shoulder ligaments and the rotator cuff muscle tendons). This bursa lessens the forces between the acromion and the shoulder capsule when the arm is moving and as it is raised overhead.

Subacromial bursitis results when the bursa becomes inflamed. This inflammation can occur as a result of overuse and impingement of the shoulder, but may also occur in association with other medical conditions, such as rheumatoid arthritis, polymayalgia and gout.

FACTORS

If shoulder impingement is the primary cause of the bursitis, moving into the position of impingement can further the injury. Impingement is reached while raising the arm above shoulder-height, to the side or forwards, combined with some inward turning of the arm. Avoidance of these positions may allow the injury to begin healing, but to properly treat this condition you need to understand the individual biomechanics. Together, this will rehabilitate the injury and prevent it from re-occurring.

The position of the scapula on the thorax (upper torso) through movement is quite variable from person to person. The state of the scapulothoracic joint will greatly affect the subacromial space during function. This scapulothoracic variation in biomechanics (including position, strength, movement, etc...) is very often the major factor in this injury. When properly assessed, these biomechanical factors can be targeted for change. Ultimately, this is the key to effective rehabilitation.

One somewhat uncontrollable factor in many cases of impingement is the physical structure of the acromion. Some may have an acromion that is angled downwards, thus reducing the available space under the acromion. This will result in less movement being required to reach a position of impingement, thereby making them more susceptible to injury.

PHYSIOTHERAPY TREATMENT

As each injury is unique with respect to the structures involved, the extent of damage, and the biomechanics of the individual, it is very difficult to discuss the physical therapy management fairly. General mamagement guidelines for soft tissue injuries during the early acute phase, go to the Injury Care page. It also mentions the various treatment choices that may be employed by your physical therapist.

The specific treatment should be based on a full assessment, which should include a detailed history, a full functional assessment of the injured area, a biomechanical analysis of the whole person (includes posture, movement patterns, etc...) and screening for more serious pathology.