Painful popping in the shoulder can be caused by various underlying conditions or injuries. The cause of painful popping can vary by age and mechanism of injury.  Here are some common causes of painful popping in the shoulder:

1. Rotator Cuff Injury: The rotator cuff is a group of muscles and tendons that stabilize the shoulder joint. Injuries or tears in the rotator cuff can lead to painful popping sensations when you move your shoulder.  This is more common in patients over the age of 40 and the popping is more subtle. 
2. Labral Tear: The labrum is a ring of cartilage that surrounds the shoulder socket. A tear in the labrum can cause pain and popping, particularly during certain movements.  This can occur in younger people and is the most common cause of painful popping in the younger person‘s shoulder.  This can also be associated with instability, the feeling that the shoulder dislocates or subluxes (partially dislocates).  This can vary from a subtle pop to a loud very painful pop.  
3. Bursitis: Bursitis is the inflammation of the bursa sacs, which are fluid-filled sacs that cushion the shoulder joint. Inflammation in the bursa can cause pain and popping when you move your shoulder.  The pop associated with bursitis is usually subtle and not loud.  
4. Tendinitis: Tendinitis is the inflammation of a tendon, and it can affect the tendons in the shoulder. This condition can cause pain and discomfort, especially with specific shoulder movements. The pop associated with tendonitis is usually subtle and not loud.  
5. Osteoarthritis: Osteoarthritis is a degenerative joint condition that can affect the shoulder joint. As the joint deteriorates, it can lead to painful popping sensations.  This is associated with older patients and patients with recurrent trauma such as recurrent dislocation over many years.  The popping that occurs with osteoarthritis sometimes is described as grinding.  
6. Instability: Shoulder instability occurs when the shoulder joint is loose, making it prone to dislocation or subluxation. This can cause popping sensations along with pain.  Usually the patient describes the joint as dislocating (the feeling that the arm comes out of the socket) and this is not a subtle nor questionable symptom.  
7. Overuse or Repetitive Strain: Activities that involve repetitive shoulder movements or overhead motions, such as swimming, tennis, or weightlifting, can lead to overuse injuries and painful popping.

Treatment for painful popping in the shoulder depends on the underlying cause.  At Total Orthopedics and Sports Medicine we have experts who can evaluate one for painful popping shoulders formulating a specific treatment program based on the specific cause of the pain.