Shoulder Impingement Syndrome

Shoulder Pain

Shoulder pain is very common, and shoulder impingement syndrome is one of the usual suspects, so common in fact that 20% of the population will have symptoms sometime in their lifetime. This condition is also known as Rotator Cuff Impingement.

Shoulder pain can be over the deltoid muscle region of the shoulder and can refer down the side of the arm. Shoulder impingement syndrome can be achy, constant, with sharp pain with specific movements of the arm. Clicking or popping is often reported. Lifting the arm to the side can be painful between 70 to 120 degrees. In some cases, end ranges can be limited by pain and pose significant functional limitations during reaching overhead, to the side, and behind.

Shoulder pain starts as minor pain with activity and lingers a bit at rest, radiating down the arm. Sudden pain with lifting and reaching movements. As shoulder pain continues and worsens, pain can persist into the night and disturb sleep, especially lying on the affected side. Shoulder pain will also worsen with continued use and prolonged activity.

Overhead and above shoulder activities/movements are the worst for your shoulder pain! So avoiding throwing, serving overhand, reaching overhead or behind the back (tucking in your shirt, wallet in/out of back pocket, doing up bra, brushing hair, usual way of putting jackets on/off, etc) is important to avoid continually aggravating the impinged structures.

How to Improve Shoulder Pain?

Shoulder pain may improve temporarily with rest, ice, avoiding overhead movements, changing positions/postures, and NSAIDs.

This condition involves mechanical compression under the acromion and a rigid coracoacromial arch, of the supraspinatus tendon +/- long head tendon of biceps brachia +/- subacromial bursa between the greater tuberosity of the humeral head and the coracoacromial arch. In other words, its a ‘space’ issue, more specifically lack space leading to compression and impingement on soft tissue structures, such as rotator cuff tendon(s) and bursa, eventually leading to degeneration and tearing of the rotator cuff tendon.

Stages

According to Neer Classification of rotator cuff impingement⁷, this impingement can be a result of the Primary (anatomical shape of the area the tendon glides is changed) and Secondary (instability in the joint that pulls the joint into unbalanced / impingement position).

• Stage 1: Edema, hemorrhage (usually <25 y/o). This stage usually is reversible with non-operative treatment
• Stage 2: Tendinopathy/Bursa irritation and fibrosis (usually 25-40 y/o).  The rotator cuff tendon progresses to fibrosis and tendinopathy. As this condition progresses and shoulder pain worsens, it may lead to mechanical disruption of the rotator cuff tendon and to changes in the coracoacromial arch with osteophytosis (extra ‘bumpy’/irregular bone formation along the anterior acromion.
• Stage 3: Bone spurs and tendon rupture (usually >40 y/o).  In certain cases requiring surgical anterior acromioplasty and rotator cuff repair.

Mechanism of Injury is typically insidious, over a period of weeks to months. However, shoulder pain can arise following an incident/trauma. Most often, repetitive compression eventually leads to irritation and inflammation of these structures. It is the forced overload/mechanical compression to the biceps +/- supraspinatus tendons, subacromial bursa and/or capsule during the abduction, forward flexion and internal rotation of the shoulder, that cause irritation of the shoulder and lead to shoulder pain.

Factors Cause Shoulder Pain

Factors that make you vulnerable to developing this shoulder pain condition are :

• Age (always seems to get us!) – degeneration
• Sports: overhead movements – throwing, swimming, volleyball, baseball, tennis, etc.
• Work:  repetitive overhead (above shoulder) work – construction, painting
• Home: repetitive movements overhead – painting, reaching for things
• Posture – protracted scapulae (aka ‘rounded shoulder’ posture) decrease the ability of scapulae to rotate upward, therefore increasing the risk of impingement with the humerus
• Anatomical deformities – acromion (different bony shapes / sizes / oritentation)

A registered physiotherapist can utilize numerous movement and ‘special’ tests to confirm the likelihood of shoulder impingement syndrome as the cause of your shoulder pain or other differential diagnoses. These tests may include: Range of motion, Strength, Hawkins Impingement Test, Empty can test, drop arm test, speed test, painful arc, etc.

The good news is that shoulder pain from shoulder impingement is treatable (non-operatively or operatively) if correct diagnosis and treatment is applied.  As a result 60-90% of patients improve and are symptom-free with physiotherapy.

See our next blog on Shoulder impingement syndrome treatment for treatment options to address shoulder pain. If you would like to get started on the road to recovering from your shoulder pain, please contact our downtown Vancouver physiotherapy info@vansportsphysio.com or call 604.661.8878.