Latest News - Aspendale Gardens | Back In Motion

What is the rotator cuff?

Published: January 3, 2020

You’ve probably heard of somebody speaking about the rotator cuff - whether it be through personal injury or from a GP. But what is the rotator cuff? What is it’s function? And what problems can arise from a rotator cuff injury?


What is the rotator cuff?

The Rotator Cuff (RC) is a common name for the group of 4 muscles and their tendons - Supraspinatus, Infraspinatus, Teres minor and Subscapularis, Each arising from a different part of the shoulder blade and connecting to the head of the humerus, forming a cuff around the glenohumeral or shoulder joint (click on the image at the end of the article).


What does it do?

The RC muscles are each used in a variety of upper extremity movements including flexion, abduction, internal rotation and external rotation. They are essential players in almost every type of shoulder movement. Balanced strength and flexibility in each of the four muscles is important in maintaining functioning of the entire shoulder girdle.

As a group, the rotator cuff muscles are responsible for stabilizing the shoulder joint, by providing the “fine tuning” movements of the head of the humerus within the glenoid fossa or the ‘shoulder socket’. They are deeper muscles and are very active in the neuromuscular control of the shoulder complex during upper extremity movements. They keep the head of the humerus within the small glenoid fossa of the shoulder blade in order to enlarge the range of motion in the GH joint and avoid mechanical obstruction (such as a biomechanical impingement during shoulder elevation). It is well documented that RC dysfunctions can lead to shoulder pain, impaired functional capacities and a reduced quality of life.


What can go wrong?

RC injuries are common injuries that can occur at any age. In younger subjects, most injuries occur secondary to trauma or arise from overuse due to overhead activities (eg. tennis, cricket, volleyball). The incidence of  rotator cuff injuries increases with age, however some individuals with rotator cuff pathology may be asymptomatic. 

The RC muscles can fall victim to muscle degeneration, impingement and tearing with advancements in age. Poor biomechanics, such as postural dysfunction or abnormalities can prematurely affect the quality of the RC muscles and tendons due to repetitive strains and tissue impingement.

Most common injuries to the RC are as follows:

  • Rotator Cuff Tears - micro or macro tearing of the muscles or tendons.
  • Rotator Cuff Tendinitis - acute inflammation of the RC soft tissue.
  • Rotator Cuff Tendinopathy - chronic irritation or degeneration of the RC soft tissue.
  • Sub-acromial impingement - biomechanical dysfunction of the shoulder complex with causes abnormal wear and tear on the RC soft tissue.


What are the signs of an RC injury?

It is important to note that RC tears or injuries are not always associated with pain or patient-reported loss of function. But it is also worth noting that asymptomatic patients may develop symptoms in a relatively short period of time.

The most common signs of rotator cuff injuries are:

  • Pain (may or may not be present) - can be localized to anterior / lateral aspect of the shoulder, with referred pain down the upper arm.
  • Painful and/or restricted range of motion.
  • Muscle weakness in the shoulder joint.
  • Functional impairments - difficulty lifting, pushing, overhead movements and movements with hand behind the back.

Next week we will discuss the importance of the rotator cuff in various sport such as cricket and tennis and how to rehabilitate a rotator cuff injury.

If you are experiencing shoulder pain and are concerned that you may have a rotator cuf injury, book in for a free assessment with a Physiotherapist at Back in Motion Aspendale Gardens by calling 9580 1985 or online.

Click on the images below to expand.