The Shoulder
The shoulder joint is made up of a ball, called the head of the humerus and a socket, called the glenoid, which extends from the shoulder blade. The surfaces of the ball and the socket are covered by a smooth layer of cartilage which facilitates smooth movement in the joint.
The ball is stabilised in the centre of the socket by a ring of fibrous tissue called the labrum. The Biceps tendon is a long cord like structure which attaches to the top part of the labrum and helps stabilise the joint.
The rotator cuff is made up of four tendons which form a covering around the head of the humerus and helps maintain stability of the ball in the socket. It also helps to lift and rotate your arm.
Common shoulder conditions
Arthritis - the wearing away of the smooth cartilage which covers the surfaces of the bones
Shoulder Instability - when the ball part of the joint slips or pops out of the socket as a result of overuse of injury
Rotator Cuff Tears - tear of one or more of the tendons which form the rotator cuff
Biceps rupture – tear of the tendons which attach the bicep muscle to the shoulder
Shoulder impingement – a condition where the shoulder blade puts pressure on the soft tissue underneath when lifting your arm
Diagnosing Shoulder Conditions
Physical examination – depends on history and disability and type of injury
X-Ray – diagnostic imaging used to show injuries or abnormalities to the bone
Magnetic Resonance Imaging (MRI) – is a non-invasive diagnostic scan which uses a strong magnetic field and computer-generated radio waves to produce detailed images of the tissues and organs inside of the body
Computerised tomography (CT )- A combination of multiple Xray images taken at different angles and processed on a computer to produce clear cross-sectional images of the bones and soft tissue in the body
Ultrasound scan – an imaging method which uses high-frequency sound waves to produce images of structures inside the body
Shoulder Arthroscopy - a minimally invasive procedure performed to diagnose and/or treat shoulder conditions and injuries
References
Shoulderdoc (2022) Bones & Joints of the Shoulder. Accessed 18 September 2022
Sonnabend D. H. and Young, A.A. (2009) Comparative anatomy of the rotator cuff. The Journal of Bone and Joint Surgery. British volume. Vol. 91-B, No. 12