Shoulder Impingement

The shoulder is a ball-and-socket joint with a complex anatomy designed for a wide range of motion. The rotator cuff, a group of muscles and tendons that stabilize the shoulder, passes through a narrow space beneath the acromion (the bony prominence at the top of the shoulder). There is also a lubricating sac called a bursa between the rotator cuff and the bone at the top of the shoulder.

Shoulder impingement, also referred to as subacromial impingement syndrome, occurs when the rotator cuff tendons and bursa in the shoulder joint are compressed by the top of the shoulder (the acromion) during arm movement. This compression leads to irritation, inflammation, and in some cases, long-term damage to the soft tissues.

Symptoms of shoulder impingement can vary in severity and may worsen with time if left untreated. Common signs include:

1. Pain: Discomfort is typically felt on the front or side of the shoulder, particularly during activities that involve raising the arm, such as reaching overhead or lifting.
2. Weakness: Individuals may notice reduced strength in the affected shoulder, particularly during overhead motions.
3. Stiffness: The shoulder may feel tight or stiff, making it difficult to perform everyday tasks like reaching behind the back or combing hair.
4. Pain at Night: Many individuals report increased pain while lying on the affected shoulder or during sleep, which can disrupt rest and recovery.
5. Clicking or Popping Sensations: Some may experience audible or tactile sensations in the shoulder when moving the arm.
6. Reduced Range of Motion: Over time, impingement can restrict the shoulder’s range of motion, making activities like throwing or swimming challenging.

Shoulder impingement can result from a variety of factors, ranging from anatomical predispositions to repetitive stress:

1. Overuse and Repetitive Movements: Athletes and individuals engaged in repetitive overhead activities—such as swimming, tennis, or painting—are particularly prone to shoulder impingement. Repeated use can irritate the rotator cuff tendons and bursa, leading to inflammation and narrowing of the subacromial space.
2. Anatomical Variations: Some people have naturally narrower subacromial spaces or bone spurs on the acromion, which can increase the risk of impingement. These anatomical factors can make the space tighter even without injury or overuse.
3. Poor Posture: Rounded shoulders and forward head posture, often resulting from prolonged desk work or poor ergonomic habits, can alter the alignment of the shoulder joint, increasing the risk of impingement.
4. Weak or Imbalanced Shoulder Muscles: Weakness or imbalances in the rotator cuff or surrounding muscles can compromise shoulder stability, making the tendons more susceptible to pinching.
5. Injury or Trauma: Acute injuries, such as falls or direct impacts, can lead to inflammation or changes in the shoulder anatomy that precipitate impingement.
6. Aging: As people age, the rotator cuff tendons may naturally degenerate or develop calcifications, increasing the likelihood of impingement.

Accurate diagnosis of shoulder impingement is essential to guide effective treatment. Dr. Connor Ziegler employs a comprehensive approach that includes a detailed history, physical examination, and imaging studies to confirm the condition.

1. Medical History: The diagnostic process begins with a thorough discussion of the patient’s symptoms, activities, and medical history. Questions about the onset, duration, and severity of pain, as well as any recent injuries, help identify potential causes.
2. Physical Examination: During the physical exam, Dr. Ziegler assesses shoulder mobility, strength, and areas of tenderness. Specific tests, such as the Neer’s test and Hawkins-Kennedy test, may be performed to provoke symptoms and confirm the presence of impingement.
3. Imaging Studies:
   • X-rays: X-rays can reveal bony abnormalities, such as spurs on the acromion or signs of arthritis, that may contribute to impingement.
   • Ultrasound: This imaging modality is useful for evaluating the rotator cuff tendons and bursa for signs of inflammation or tears.
   • MRI: An MRI provides a detailed view of the soft tissues in the shoulder, helping to identify rotator cuff injuries, bursitis, or other underlying conditions.
4. Differential Diagnosis: Shoulder impingement symptoms can overlap with other conditions, such as rotator cuff tears, frozen shoulder, or shoulder instability. Dr. Ziegler ensures a precise diagnosis by ruling out these possibilities.