Shoulder impingement refers to a condition where the rotator cuff tendons or other soft tissues in the shoulder become compressed or irritated, resulting in pain and limited mobility. If not treated properly, impingement can lead to injuries like tendinitis and even rotator cuff tears.

Primary vs. Secondary Impingement
There are two main types of shoulder impingement. Here’s the difference between the two:

Primary Shoulder Impingement: This type of impingement occurs due to structural abnormalities or changes within the shoulder joint itself. This leads to direct rubbing of the rotator cuff tendon by surrounding bony structures, particularly in an area called the subacromial space, which is found between the humerus and the acromion. Structural abnormalities can include bone spurs, hooked or downward-sloping acromion, as well as inflammation.

Secondary Shoulder Impingement: Secondary impingement occurs when the compression or irritation of the soft tissues in the shoulder is not due to structural abnormalities within the joint.

Instead, it is often caused by problems originating from outside the shoulder joint, such as:

• Muscle imbalances – Weakness or imbalance in the muscles surrounding the shoulder, particularly the rotator cuff and scapular stabilizers, can alter the mechanics of the joint, leading to impingement.
• Poor posture – Forward head and rounded shoulders, excessive thoracic rounding, or other postural deviations can affect the position and movement of the shoulder, increasing the risk of impingement.
• Overuse or repetitive activities – Engaging in repetitive overhead motions, such as throwing, swimming, or weightlifting, without proper technique or adequate rest can contribute to secondary impingement.
• Trauma or injury – Previous shoulder injuries, such as dislocations, fractures, or muscle tears, can lead to altered shoulder mechanics and subsequent impingement.

What Does Impingement Feel Like?

Both kinds of impingement can present with similar or even identical complaints. People with shoulder impingement usually experience recurrent or persistent “pinching” type pain with overhead movements. The location of the pain could be at the back, front or down the side of the shoulder. Popping and catching could be present but is not a common finding. As symptoms worsen, the shoulder will often begin to hurt at night.

Can Physical Therapy Help with Impingement?

Yes. Physical therapy is oftentimes indicated to treat shoulder impingement and focuses on relieving pain and restoring shoulder function. Common rehab techniques include:

• Activity Modification – Avoiding activities that exacerbate symptoms and modifying movements to minimize strain on the shoulder in the initial phases.
• Exercise Program – Strengthening the rotator cuff and the other muscles around the scapula to promote more stability of the shoulder joint.
• Patient Education – Promoting good postural habits during activity and rest/sleep as well as teaching proper mechanics with functional overhead tasks or during throwing motions in sports.