22/07/2014
A common shoulder injury- impingement of the rotator cuff
The shoulder is a ball (the head of the humerus) and socket (the glenoid) joint, which in itself isn’t very stable. As a result the shoulder capsule and surrounding muscles and ligaments are relied upon to offer stability and to allow effective shoulder function. The rotator cuff muscles comprising of supraspinatus, infraspinatus, teres minor and subscapularis ensure that the humerus head stays within the socket, often counter-acting the role of the deltoid muscle in order to achieve this.
An area where I place a lot of emphasis is the role of the muscles which control the shoulder blade. The shoulder blade plays a very important and influencing role in the movement pattern of the shoulder joint. Many clinicians would agree that the shoulder joint in fact starts at the shoulder blade. A stable shoulder blade, provides a stable foundation for the muscles which act upon the shoulder joint, including all 4 of the rotator cuff muscles mentioned above. The muscle which control the shoulder blade include trapezius, serratus anterior, rhomboids, levator scapulae and pectoralis minor. These muscle groups should be given direct attention in training programs.
Commonly in the sportsperson, impingement can occur when the muscles responsible for the stability of the shoulder blade become deficient, either due to weakness or poor motor control. This causes the shoulder blade to move in an abnormal pattern, often causing narrowing of the subacromial space. The relevance of this is that the tendons of the supraspinatus and infraspinatus travel through this subacromial space and as result can become irritated as they no longer have the same freedom of space to move in. This can worsen if the pectoralis minor muscle is tight, as this pulls the shoulder blade forward, further narrowing this space.
Signs and symptoms of impingement to recognise include:
• Pain with overhead activity
• Discomfort placing hand behind back
• Catching as you as you lift your arm up sideways especially between 70° and
120 °
If you are suffering from any of the above symptoms, please feel free to email me to organise an assessment.
Dee Ryan is the in-house Physiotherapist at SBG Concorde.