By: Dr Catherine Spencer-Smith | Published: January 12, 2012
The shoulder is wonderfully clever arrangement of three separate joints. A complex scaffold of ligaments and muscles allow it to function both as a stable platform for transmitting force through the arm, and a mechanism for hand positioning.
But mobility comes at a price, and thus the shoulder is more vulnerable to trauma and prone to overuse injuries. To compound the situation, there can often be a confusingly similar manner in the way that minor and more serious injuries can present. Additionally, the position of ‘where it hurts’ isn’t necessarily where the injury lies, as pain can be referred around the shoulder. It’s therefore really important to get an early, skilled assessment of a shoulder problem, so that the correct diagnosis and treatment can be given.
Shoulder dislocations are common in sport, and there is a high rate of re-dislocation because structures become stretched. A correctly re-located shoulder needs physiotherapy, and in the long-term, may require surgical stabilisation to prevent a recurring pattern of dislocation and chronic pain. Falls onto the shoulder, or an outstretched hand, can also damage the gristle ring lining the entrance to the socket, known as the ‘labrum’. Tears in the labrum can cause long-term pain, movement and stability issues and often go missed without the correct imaging. They may require surgical repair.
We commonly see injury to the Acromioclavicular joint in sport. The ‘ACJ’ connects two bones; the acromion (a bony arch which projects off the shoulder blade), and the clavicle (collar bone). A couple of strong ligaments (the acromioclavicular ligaments) help bind it together. The clavicle functions as a strut to hold the arm out from the chest wall, (a bit like the boom of a crane), and the ACJ experiences most loading when the arm is performing overhead movements, or is brought across the front of the chest. There is a limited amount of space underneath the acromion, and one of the rotator cuff muscle tendons, (the supraspinatus tendon), passes through this space.
The ACJ can become damaged during a fall, and overhead or power sports (such as rock climbing, boxing, weight lifting, racquet and throwing sports) can lead to gradual wear and tear of its surfaces. Pain from the ACJ is typically felt on the top of the shoulder, and may be at its worst when the hand is held directly overhead. Because of their close proximity, ACJ problems can coincide with damage to the supraspinatus tendon, particularly if joint swelling, or wear and tear bony projections (a.k.a. osteophytes) from the joint begin to ‘impinge’ on the tendon below. Additionally, this may also bring about swelling of a soft tissue structure known as a bursa. Poor postural habits, and weak ‘scapular stabilising’ muscles propagate the joint overloading, and sometimes excessive rotator cuff training is mistakenly emphasised in rehabilitation. A corticosteroid injection can help ‘tame’ a sore and swollen ACJ and impinged tendon, giving the patient a ‘window of opportunity’ to carry out important remedial exercises.
It’s important not to try to struggle on with a shoulder problem, and a prompt skilled assessment is essential to ensure early, appropriate management.
If you would like to arrange a consultation with Dr Spencer-Smith please contact the Enquiry Helpline on 0207 483 5148