rotator cuff tear

Causes of a Rotator Cuff Tear

The rotator cuff is a collection of muscles and their corresponding tendons that hold the arm in its socket and provide strength and stability. There are a variety of rotator cuff injuries that vary in intensity but have largely the same symptoms and treatment options. Tearing the rotator cuff, however, is the most extensive of the rotator cuff injuries. Here is a look at what can cause a rotator cuff tear. 

What is a Rotator Cuff Tear?

A rotator cuff tear is exactly what it sounds like: a rip in a muscle or tendon of the rotator cuff. While rest and physical therapy are often effective for less extensive injuries, tears often necessitate surgical intervention to prevent rotator cuff degeneration. When degeneration occurs, further issues like tendons detaching from the bone may occur which can interfere with the integrity of the shoulder and inhibit movement and strength. According to the American Academy of Orthopaedic Surgeons (AAOS), there are two types of tears:

  • Partial Tear: Soft tissue in the rotator cuff has torn, but the muscle or tendon is not completely severed.
  • Full-Thickness or Complete Tear: The affected muscle or tendon is literally split from the severity of the tear. Much like what occurs with degenerative disease, a torn tendon may detach from the upper arm bone, or humerus. It may not necessarily travel the length of the muscle or tendon, but essentially rips from the top to the bottom of the muscle.

Risk Factors

Rotator cuff injuries occur more often in athletes and those in occupations requiring repetitive movement of the arm at the shoulder. Baseball players, swimmers, wrestlers, rowers, and tennis players are frequently afflicted with rotator cuff issues; rotator cuff tendinitis (an inflammation of the tendons) is often referred to as swimmer’s, baseball, or tennis shoulder. 

A variety of different types of construction work can be hazardous to the rotator cuff: painting, hammering, extensive heavy lifting, and a number of similar activities all require the strength and repetition of movement in the shoulder that can damage the rotator cuff. Truck drivers are also subject to rotator cuff issues; the strength and movements required to control diesel trucks and other large vehicles can damage the shoulder long term. 

Research suggests there is likely a genealogical connection to rotator cuff injuries; having family members with shoulder issues increases your likelihood. Advancing age is another risk factor for rotator cuff injuries. As time passes, the musculoskeletal system decreases in strength; after age forty, you become much more susceptible to strains, inflammation, and tears in the rotator cuff. 

Acute Rotator Cuff Tear Causes

Acute tears essentially refer to a tear that develops as an immediate result of a shoulder injury. The AAOS refers to examples such as falling on an extended arm or jerking the shoulder while lifting something heavy. A car accident or other “acute” trauma can all cause rotator cuff tears, even with no preexisting rotator cuff injury present. 

Degenerative Rotator Cuff Tear Causes

A pre-existing issue, however, will increase the likelihood of a tear—even without an acute injury. Tendons lose strength and durability as you age, increasing the susceptibility of the rotator cuff to tear. Those who participate in activities or occupations listed as risk factors are more likely to have issues. Additionally, once one shoulder tears, the other shoulder is more likely to tear as well (possibly because of the increased load it has to carry to make up for the injured rotator cuff). 

Chronic tears may be caused by repetitive motions. Other causes include a decreased blood supply as the cardiovascular system begins to wear down and interfering with the body’s ability to heal smaller issues (like tendinitis), making these problems more likely to become a tear. Bone spurs on the acromion bone can cause a condition called “shoulder impingement” as the bone spurs rub on the rotator cuff muscles during movement; the weakness of the tendon from the impingement may also be an underlying cause for an eventual tear. If you suspect you have torn or otherwise injured your rotator cuff, seek medical treatment immediately for best results. 

Last Updated: August 31, 2016