Whether it’s a dull ache, a sharp pain, or a complete inability to move, it’s not uncommon to experience some form of shoulder pain during your lifetime. It might be the result of injury, or it might be due to overuse. Or it might seem like it appeared out of nowhere. The fact is that shoulder pain can be a symptom of a wide range of issues—and that can make it hard to know when and if you need to see a doctor.

What’s in a shoulder?

The shoulder is a complex system of bones, joints, and tissues that work together to allow you to move your arm with a wide range of motion. Some of its parts include:

  • Bones: They include the upper arm bone (humerus), the shoulder blade (scapula), and the collarbone (clavicle).
  • Socket: The top of your upper arm bone fits into a rounded socket in your shoulder blade, called the glenoid.
  • Rotator cuff: A combination of muscles and tendons called the rotator cuff keeps your arm bone centered in your shoulder socket.

What causes shoulder pain?

Shoulder pain can have a variety of causes.  The most common include:

  • Tendinitis. Tendinitis is simply inflammation of a tendon. It may be due to overuse or repetitive activities (acute tendonitis), to general wear and tear, or to conditions such as arthritis (chronic tendinitis).
  • Bursitis. Bursitis is inflammation of the bursae, which are small, fluid-filled sacs found in joints throughout the body. Bursae in the shoulder can sometimes get inflamed due to overuse.
  • Tendon tear. Shoulder tendons—often in the rotator cuff or bicep—can pull away the bone due to injury, overuse, or simple wear and tear.
  • Instability or dislocation. When the top of the upper arm bone is forced out of the shoulder socket—usually from injury or overuse—it’s called dislocation.
  • Fracture. Broken shoulder bones often cause severe pain, swelling and bruising.
  • Arthritis. Arthritis in the shoulder can cause symptoms including pain, swelling and stiffness. It often develops slowly, and the pain can worsen over time. Sometimes people end up avoiding moving their shoulder when they have arthritis pain, which can lead to stiffening or tightening of the tissues involved.

How do I know when to see a doctor for my shoulder pain?

The decision about when to seek medical care for shoulder pain comes down to two simple factors: the degree and the longevity of your pain. Ask yourself these two questions:

1) How bad is the pain? If you have intense pain, seek medical care as soon as possible. If your pain is not severe, you can wait a few days to see if rest may improve your symptoms.

2) How long have you had pain? If you’ve had shoulder pain that hasn’t improved several days after an injury, you should seek medical care. For pain that didn’t begin with an injury, you should make an appointment to see a doctor if the pain continues after a few weeks of rest and restricting any activities that might overtax your shoulder.

When you visit a doctor about shoulder pain, you may be asked for a complete medical history. You’ll likely have a thorough physical exam and possibly have tests such as x-rays, an MRI or a CT scan. Depending on what the doctor learns from those, they might prescribe rest, physical therapy, pain medication or surgery.

Leaving shoulder pain undiagnosed and untreated may lead to greater pain and loss of mobility later. Talk to your doctor now.