Shoulder Clicking: Understanding Crepitus, Common Causes, and When to Seek Help

Why Does My Shoulder Click When I Rotate It?

Shoulder clicking, medically known as crepitus, is a common phenomenon often caused by harmless gas bubbles within the joint or tendons moving over bone. However, when accompanied by pain, weakness, or limited motion, it can signal an underlying issue requiring professional assessment.

Understanding Joint Sounds (Crepitus)

Joint sounds, including clicking, popping, grinding, or cracking, are collectively referred to as crepitus. While these sounds can sometimes be alarming, it's crucial to differentiate between asymptomatic crepitus (noise without pain or other symptoms) and symptomatic crepitus (noise accompanied by pain, weakness, instability, or loss of motion). The shoulder, being the most mobile joint in the body, is particularly prone to making various sounds due to its complex structure and wide range of motion.

The Complex Anatomy of the Shoulder

To understand why your shoulder might click, it's essential to appreciate its intricate anatomy:

• Bones: The shoulder is formed by three bones: the humerus (upper arm bone), scapula (shoulder blade), and clavicle (collarbone). The glenohumeral joint, a ball-and-socket joint, connects the humerus to the scapula.
• Articular Cartilage: The ends of these bones are covered with smooth articular cartilage, allowing them to glide seamlessly against each other.
• Joint Capsule and Synovial Fluid: The joint is enclosed by a fibrous capsule lined with a synovial membrane, which produces synovial fluid. This fluid lubricates the joint, reduces friction, and nourishes the cartilage.
• Labrum: A ring of cartilage called the labrum deepens the shallow socket (glenoid) of the scapula, providing additional stability for the humeral head.
• Rotator Cuff: A group of four muscles and their tendons (supraspinatus, infraspinatus, teres minor, subscapularis) surround the joint, providing dynamic stability and facilitating rotation and abduction.
• Bursae: Small, fluid-filled sacs (bursae) are located around the joint, acting as cushions to reduce friction between bones, tendons, and muscles.
• Ligaments: Strong, fibrous bands that connect bones to bones, providing passive stability.

The shoulder's remarkable mobility comes at the cost of stability, making it susceptible to various mechanical issues that can lead to clicking.

Common, Benign Causes of Shoulder Clicking

Most instances of shoulder clicking are harmless and do not indicate a serious problem.

• Articular Cavitation (Gas Bubbles): This is the most common cause of joint popping, not just in the shoulder but in many joints (like cracking knuckles). Synovial fluid contains dissolved gases (oxygen, nitrogen, carbon dioxide). When the joint is stretched or compressed, the pressure within the joint changes rapidly, causing these gases to form bubbles. When the joint moves further, these bubbles can collapse or burst, producing an audible "pop" or "click." This phenomenon is typically painless and occurs without any underlying pathology.
• Tendon or Ligament Snapping Over Bony Prominences:
  • Biceps Tendon: The long head of the biceps tendon runs through a groove in the humerus. If the tendon is slightly loose or the groove is not perfectly smooth, the tendon can briefly catch or snap as it moves during shoulder rotation, producing a click.
  • Scapular Crepitus: Sounds can originate from the scapula moving over the rib cage. This can happen if there are minor irregularities on the underside of the scapula or the ribs, or if the muscles surrounding the scapula are tight or imbalanced, causing friction.
  • Other Tendons/Ligaments: Any tendon or ligament that crosses a bony structure can potentially snap over it, especially during specific movements, if there's minor anatomical variation or muscle imbalance.

These benign causes are generally characterized by the absence of pain, swelling, warmth, or functional limitations.

When Shoulder Clicking May Indicate a Problem

While many clicks are benign, some types of clicking, especially those accompanied by other symptoms, can signal an underlying issue that requires medical attention.

• Labral Tears: The labrum can tear due to acute injury (e.g., dislocation, fall) or repetitive stress. A torn labrum can cause clicking, catching, grinding, and a sensation of instability, often accompanied by pain, especially during overhead movements.
• Rotator Cuff Tendinopathy or Tears: Inflammation (tendinopathy) or tears in the rotator cuff tendons can lead to clicking or grinding sounds. This occurs because the damaged or inflamed tendon may not glide smoothly, or the humeral head's position changes due to muscle weakness, causing friction. Pain, weakness, and restricted movement are common accompanying symptoms.
• Bursitis: Inflammation of the bursae (e.g., subacromial bursa) can cause a clicking or grinding sensation, often with significant pain, tenderness to touch, and limited range of motion. The inflamed bursa can thicken and rub against surrounding structures.
• Osteoarthritis (Degenerative Joint Disease): As the smooth articular cartilage wears away, bone can rub against bone, leading to a gritty, grinding, or popping sensation. This is typically accompanied by pain, stiffness, and reduced mobility, especially in older individuals.
• Shoulder Instability or Subluxation: If the shoulder joint is loose (hypermobile), the humeral head can shift excessively within the socket, leading to clunking or popping sounds as it momentarily slips out of alignment (subluxation) before relocating. This is often associated with a feeling of apprehension or "giving way."
• Adhesive Capsulitis (Frozen Shoulder): In the early, painful stages of frozen shoulder, reduced mobility and inflammation of the joint capsule can sometimes lead to compensatory movements or internal friction that results in clicking or grinding.
• Fractures or Loose Bodies: In rare cases, a previous fracture that healed imperfectly or a loose piece of cartilage or bone within the joint can cause mechanical clicking or locking.

When to Seek Professional Medical Advice

While an isolated, pain-free click is usually nothing to worry about, it's advisable to consult a healthcare professional, such as a doctor, physical therapist, or sports medicine specialist, if your shoulder clicking is accompanied by any of the following symptoms:

• Pain: Especially sharp, persistent, or worsening pain during or after movement.
• Weakness: Difficulty lifting or moving your arm, or a noticeable loss of strength.
• Limited Range of Motion: Inability to move your arm through its full normal arc.
• Locking or Catching: A sensation that the joint is getting stuck or momentarily seizing.
• Instability: A feeling that your shoulder is going to "give out" or dislocate.
• Swelling or Warmth: Signs of inflammation around the joint.
• Clicking that develops suddenly after an injury or trauma.
• Clicking that progressively worsens over time.

A professional can perform a thorough physical examination, potentially order imaging tests (X-rays, MRI, ultrasound), and accurately diagnose the cause of your shoulder clicking, leading to an appropriate treatment plan.

Managing and Preventing Shoulder Clicking

Management of shoulder clicking depends entirely on its cause.

• For Benign Clicking (No Pain or Other Symptoms):

  • No specific treatment is needed.
  • Focus on maintaining overall shoulder health through regular, balanced exercise.
  • Ensure proper warm-up before activity and cool-down afterward.

• For Problematic Clicking (With Pain or Other Symptoms):

  • Physical Therapy: This is often the cornerstone of treatment. A physical therapist can:
    • Assess your posture, movement patterns, and muscle imbalances.
    • Prescribe specific exercises to strengthen the rotator cuff and scapular stabilizing muscles.
    • Improve joint mobility and flexibility.
    • Teach proper biomechanics for daily activities and exercise.
  • Rest and Activity Modification: Temporarily avoiding movements that aggravate the clicking and pain can help reduce inflammation and promote healing.
  • Anti-inflammatory Measures: Ice application and, if appropriate, over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs) can help manage pain and inflammation, but should be used under guidance.
  • Ergonomic Adjustments: Modifying your workspace, sleep position, or exercise technique to reduce stress on the shoulder.
  • Injection Therapy: In some cases, corticosteroid injections may be used to reduce inflammation and pain.
  • Surgery: For severe cases, such as large rotator cuff tears, significant labral tears, or chronic instability that doesn't respond to conservative treatment, surgical intervention may be necessary.

Conclusion

Shoulder clicking is a common occurrence, and in most instances, it's a normal and harmless phenomenon related to joint mechanics or tendon movement. However, the presence of accompanying symptoms like pain, weakness, or instability transforms a benign sound into a potential red flag. Listening to your body and seeking timely professional evaluation when symptoms arise is crucial for an accurate diagnosis and effective management, ensuring the long-term health and function of your shoulder joint.