The shoulder is one of the most complex compound joints in the human body. Not only does it allow you to move your arms, but it also transfers forces between the arms and body. As such it is made up of a variety of structures, bones, muscles, connective tissues, blood vessels, and nerves.

When any one of them is injured, experiences inflammation or damage, it can have a profound impact on the entire shoulder. Not to mention a negative impact on your overall quality of life.

With so many different structures, many things can cause shoulder pain, it can sometimes be hard to determine the true underlying cause.

What Are Common Causes Of Shoulder Pain?

Many things can cause shoulder pain, including injuries, inflammation, tendonitis, and arthritis, just to name a few. The following are some of the more common causes of shoulder pain, and their related symptoms

Injury or Inflammation In The Rotator Cuff

The rotator cuff is essentially a group of muscles tendons and other connective tissues that connects the humeral head of the shoulder to the socket. It plays an essential role in moving your arm in a circular motion. Injury and inflammation in the rotator cuff are one of the most common causes of shoulder pain.

Common symptoms of a rotator cuff injury include:

  • Stiffness when you lift your arm above your head
  • Sudden or increasing pain when you lift your arm or put your arm behind your back.

Rotator Cuff Tears

A tear in the rotator cuff can be classified as partial or total. A partial tear means that some percentage of connective tissue is still structurally sound. In a case like this, rehabilitation might be able to improve symptoms. A complete rotator cuff tear will typically cause weakness in the arm or a complete limitation of movement. Most complete rotator cuff tears require some type of surgical intervention or reconstruction.

Rotator Cuff Impingement

This is another type of rotator cuff problem that affects several of the surrounding structures. It’s usually associated with inflammation, irritation, and possibly compression in the bursa sac that cushions the shoulder in the socket. It’s most often the result of an injury or repetitive stress.

A rotator cuff impingement treatment plan might include things like rest, the use of a sling, rehabilitative exercise, or a carefully placed injection of cortisone.

Calcific Tendinitis

This condition occurs when calcium deposits gradually start to build upon the tendons of the rotator cuff. It’s often associated with a past injury to the connective tissue that may have healed incorrectly. It can also be a long-term complication of a partial rotator cuff tear.

Calcific Tendinitis is more common in middle-aged and older adults. Individuals with uncontrolled blood sugar such as diabetics also seem to be more prone to developing Calcific Tendinitis

The treatment process is intended to relieve pain while also preserving the shoulder’s range of motion. This might call for the use of over-the-counter or prescription anti-inflammatory medications, as well as cortisone injections, and physical therapy. If these treatments don’t improve symptoms surgical intervention might be required to remove the calcium deposits from the affected tissues.

Acromioclavicular Joint Separation

Also known as an AC separation this is another component of the shoulder that is a very common injury in athletes and physically active people. It’s often associated with a hard fall or overexertion from pressing motions.

The joint is connected to the clavicle or collar bone. It further helps with transferring force from the arms to the torso. When the joint separates from the scapula or shoulder blade. Sometimes this partially severs or completely disconnects the AC ligament.

There are several different degrees of AC separation. In some severe cases, the distal clavicle contacts the shoulder blade or other structures in the shoulder. This degree of AC joint separation usually requires surgical intervention. Though in most mild cases the AC joint will heal itself through rest and rehabilitative exercise. If inflammation causes complications, a cortisone shot may need to be injected into the joint.

AC Joint Osteolysis

In some severe AC joint injury, the distal clavicle itself is damaged or experiences a stress fracture. In some cases of AC joint osteolysis repetitive stress causes bone erosion very similar to arthritis. In some of these cases, rest and gradual rehabilitative exercise might be enough to restore the natural state of the bone and the relationship to the cartilage and surrounding connective tissues.

Though in a severely acute case, or a case where chronic inflammation has caused bone deformation, a distal clavicle resection might need to be performed. This outpatient surgical procedure essentially trims 5 to 10 millimeters of bone from the end of the distal clavicle. In time fibrous scar tissue fills the void and replicates the natural structure of the compromised AC joint.

Adhesive Capsulitis

Sometimes called “Frozen Shoulder” adhesive capsulitis is a gradual thickening and stiffening of the tissues surrounding the shoulder joint. It’s most common in people age 40 to 60 and is more common in women as well as individuals with diabetes, high cholesterol, or thyroid problems.

Adhesive Capsulitis is also a somewhat common complication associated with a rotator cuff impingement or tendon tear. In some severe cases, the shoulder may become frozen for weeks before symptoms abate.

Physical therapy can often improve frozen shoulder, but can also cause discomfort. Most Adhesive Capsulitis treatment plans also include the use of nonsteroidal anti-inflammatory drugs and cortisone injections. In some cases, surgical intervention is required.


While more commonly associated with knee and hip problems osteoarthritis can also affect the shoulder. Especially if the individual has had past problems with chronic inflammation. It develops when the cartilage that cushions the bones in the shoulder degrade which causes the bones to rub against one another. An effective treatment plan often starts with things like activity modification and anti-inflammatory drugs, though cortisone injections may be needed to reduce complications caused by chronic inflammation.

If the affected shoulder doesn’t show gradual improvement surgical intervention might be needed. In a severe case, the only effective treatment plan might be a partial or complete shoulder replacement.

Partial Or Complete Tear Of The Labrum

The shoulder labrum is a thick section of tissue that attaches to the rim of the shoulder socket. It helps keep the humeral head or ball of the joint in place. There are several degrees and types of a labrum tear. Some occur along the edge of the labrum which causes discomfort.

With rehabilitation, the natural function of the labrum might be fully restored. If the labrum is completely torn off the bone, surgical intervention may be needed to fully repair the joint. Many labrum injuries also include some degree of bicipital tendonitis and inflammation. If so, a corticosteroid injection might be needed to treat the affected bicipital tendon.