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Shoulder impingement occurs when soft tissues such as tendons get compressed or “pinched” within tight spaces in the shoulder. The most common cause of shoulder impingement involves the rotator cuff tendons getting squeezed between the head of the upper arm bone (humerus) and the rim of the shoulder blade (acromion) when the arm is lifted. This compression damages the tendons over time and leads to pain and reduced shoulder movement.
Causes of Impingement Syndrome
The main causes that can lead to shoulder impingement include:
– Poor shoulder mechanics: Repeated overhead arm motions like serving in tennis or throwing a ball frequently without allowing adequate rest and recovery can wear down the rotator cuff tendons.
– Tight muscles: Having very tight shoulders, chest or upper back muscles limits shoulder mobility and predisposes the tendons to impingement.
– Bone spurs: Growths of extra bone (bone spurs) developing on the acromion can pinch the tendons more severely during arm movements.
– Injury or trauma: Prior shoulder dislocations, fractures or repetitive overuse injuries can damage the rotator cuff and lead to impingement over time.
– Posture issues: Poor sitting or standing posture that protrudes the shoulders forward chronically compresses the tendons.
Symptoms of Impingement Syndrome
The main symptoms of shoulder impingement include:
– Gradual onset of shoulder pain: Pain develops gradually over time rather than suddenly from an injury. It is typically felt at the front or side of the shoulder.
– Pain with overhead activities: Reaching high cabinets or lifting objects overhead commonly provokes sharp pain.
– Sleep difficulties: Lying on the affected shoulder or lifting the arm above head while sleeping causes pain.
– Catching & locking: The shoulder may feel like it is catching or temporarily locking into place during elevation.
– Weakness: As the condition progresses, rotator cuff weakness leads to an inability to lift or carry heavier objects with the affected arm.
– Referral pain: Pain may radiate out from the shoulder down the arm.
Treatment Methods for Impingement Syndrome
The primary treatments for shoulder impingement are:
– Rest and modification of activities: Avoiding overhead strains and allowing for rest periods is needed for recovery.
– Ice & heat therapy: Applying ice reduces pain and inflammation, while heat improves local blood flow and relaxation.
– NSAIDs: Over-the-counter anti-inflammatory drugs like ibuprofen help reduce pain and swelling.
– Physical therapy: Strengthening the rotator cuff muscles and stretching tight shoulder areas is focused on. Therapy also addresses postural issues.
– Corticosteroid injections: For acute severe cases, corticosteroid medications injected into the shoulder joint calm inflammation and pain.
– Surgery: If non-surgical methods fail after 3-6 months, arthroscopic shoulder surgery may be needed to properly diagnose and treat any bone spurs or soft tissue damage present. Recovery takes several months.
With appropriate nonsurgical treatment, most cases of impingement syndrome can resolve within a few months. Following the treatment plan given by one’s physician and making lifestyle modifications are important for long-term resolution of symptoms. Recurrence is common if the underlying causes and biomechanical abnormalities are not addressed.
Subacromial Impingement: A Specific Type of Shoulder Impingement
Subacromial impingement is a more specific diagnosis under the broad category of shoulder impingement syndrome. It occurs when the rotator cuff tendons become pinched in the subacromial space, which is the narrow channel that exists under the acromion bone at the top of the arm bone (humerus).
This type of impingement is very common, accounting for approximately 50% of all shoulder pain cases seen in clinical practice. The subacromial space can become narrowed due to various factors like bone spurs or inflammation in addition to repetitive overhead motions.
Distinguishing Features of Subacromial Impingement
Some distinguishing clinical features of subacromial impingement syndrome compared to other shoulder issues include:
– Pain localized to the front or side of the shoulder near the acromion.
– Tenderness directly underneath the acromion bone upon palpation.
– Pain clearly reproduced by shoulder impingement tests done by the physician.
– Symptoms worsen with shoulder flexion or elevation against resistance.
– Symptoms improve with the arm in a neutral hanging position.
Treatment for Subacromial Impingement
The main treatment goals are to decrease inflammation, improve shoulder mobility, and strengthen the rotator cuff muscles. This is primarily accomplished through:
– Oral NSAIDs and corticosteroid injections for severe acute cases.
– Physical therapy focused on stretching tight areas like the pectorals along with strengthening exercises.
– At-home exercises aimed at pendulum swings, self-mobilizations, and rotator cuff strengthening.
– Activity modification including limiting overhead activities that provoke symptoms.
– Surgery (decompression or repair procedures) if lengthy conservative management fails to provide relief.
– Alternatives like acupuncture, massage, or bracing may be beneficial as well.
Subacromial impingement syndrome tends to respond well to non-surgical management, provided.
