what is the rotator cuff?

What is the rotator cuff?

The rotator cuff is a group of  4 muscles which keep the head of your upper-arm bone (humerus) in your shoulder socket. It  helps  raise, lower, and rotate your arm, keeping the shoulder stable and safe throughout these movements.

There are 4 muscles that make up your rotator cuff

  • supraspinatus
  • infraspinatus
  • teres minor
  • subscapularis.

The supraspinatus holds the humerus in place and keeps the upper arm stable.  It also helps to lift the arm out to the side. The infraspinatus is the main muscle that allows your shoulder to extend and rotate outward. The teres minor is the smallest  and is there to help outward rotation. The subscapularis holds your upper arm bone to your shoulder blade and helps to lower your arm back down, and rotate the arm inward.

Rotator cuff tear

You’ve probably heard of a rotator cuff tear.  As the rotator cuff is quite complex with 4 individual muscles working together it can have multiple causes.

Unlike many muscle tears where there is often a  traumatic event such as a fall  rotator cuff injuries take time to develop and are often caused by overuse.   Sometimes a form of tendonitis occurs first caused by inflammation of the associated tendon due to overuse, but that inflammation over time  can lead to damage, making you more prone to a tear.

Risk factors

As the joint is so complex and there are so many injuries that can affect it there are a lot of risk factors.  For example:

  • sports that use repetitive arm motions such as golfers,  swimmers, and tennis players
  • work involving repetitive movements of the shoulder such as a plasterer, assembly line worker or painter
  • genetics – some families seem to get this type of injury more.  This could be due to minor differences in shoulder anatomy or a predisposition to thinning of muscle tisue
  • presence of arthritis in the shoulder joint as this makes the joint weaker
  • age – rotator cuff injuries become more common with age especially as you get over 60

This depends on the severity of the tear or injury and the muscle that is torn. A partial tear will generally consist of physiotherapy but may also include anti-inflammatory medication to help with swelling.

Over time if there is no improvement in the tear, your doctor may try other forms of treatment.

For a complete rotator cuff tear, also known as a full-thickness tear, surgery is often required. Physiotherapy after surgery is required to  help regain shoulder function.

Strengthening the shoulder muscles with special exercises and keeping active not only helps to heal the partial tear but may also help prevent future tears.

If you suspect you might have a rotator cuff tear see your GP as soon as possible as  time is of the essence when dealing with an acute rotator cuff tear because when missed for a period, the muscle-tendon unit can retract, making treatment difficult.


Even if you have numerous risk factors or even have a history of rotator cuff injury, there are several ways that you can prevent an injury to your rotator cuff.

  • warm up your shoulders before activity – arm circles and some easy stretches are perfect.
  • if doing lots of repetitive movements involving shoulders take frequent breaks
  • be careful lifting weights – get help lifting very heavy items
  • massage can help reduce inflammation and keep the shoulder moving freely
  • if your shoulder is weak a few sessions with a PT to get a routine to strengthen your shoulders might help

Anna is a Sports Therapist and massage therapist and owns Relax Therapies in Birkenhead.

If you have any questions you can contact her here 

See Online Booking Page

Leave a Reply

Your email address will not be published. Required fields are marked *