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The shoulder joint

The shoulder joint

The shoulder is the most mobile joint in the human body and allows an enormous range of movement. It is formed by the head of the upper arm bone (humerus), the shoulder socket (glenoid) and the shoulder blade (scapula). This complex anatomy allows movement in every direction, but also makes the joint susceptible to injury and wear.

The shoulder joint – function & biomechanics

The most mobile joint in the human body

Function of the shoulder joint

The shoulder allows:

  • Abduction and adduction (raising and lowering)
  • Flexion and extension (forwards and backwards)
  • Internal and external rotation
  • Combined movements (for example overhead activities)

This freedom of movement is essential for everyday activities such as dressing, washing and sport.

Biomechanics of the shoulder

Joint stability:

  • The rotator cuff as a dynamic stabiliser
  • The labrum as a static stabiliser
  • The capsule and ligaments

Range of movement:

Up to 180° of abduction and 170° of flexion are possible.

Force transfer:

The rotator cuff centres the head of the humerus in the socket.

Shoulder blade movement:

The shoulder blade rotates and glides to allow optimal freedom of movement.

Health & prevention

Because of its mobility, the shoulder is susceptible to:

  • Rotator cuff tears
  • Shoulder dislocations
  • Impingement syndrome
  • Frozen shoulder
  • Labral lesions

Prevention:

  • Strengthening the rotator cuff
  • Stretching the chest muscles
  • Avoiding overhead work
  • Good posture and ergonomics

In summary

The shoulder is a complex system of bone, muscle, tendon and ligament. Keeping it healthy in the long term depends on targeted training, good posture and having symptoms assessed early.

The team at Sportklinik Freiburg will be glad to help you with this.

Common causes of shoulder pain

Illustration of Rotator cuff tear
Conditions
Rotator cuff tear
Injury to or wear of the rotator cuff
Illustration of Calcific tendinitis of the shoulder
Conditions
Calcific tendinitis of the shoulder
Pain caused by calcium deposits in the shoulder tendon
Illustration of Rupture of the long head of the biceps tendon
Conditions
Rupture of the long head of the biceps tendon
usually caused by overuse; it leads to pain, loss of strength and a visible change in the shape of the muscle.
Illustration of Shoulder osteoarthritis
Conditions
Shoulder osteoarthritis
Shoulder osteoarthritis is the wearing away of the joint cartilage in the shoulder
Illustration of Shoulder impingement
Conditions
Shoulder impingement
Painful narrowing of the space around the rotator cuff tendons in the shoulder joint
Illustration of Shoulder instability
Conditions
Shoulder instability
Excessive mobility of the shoulder joint with recurrent partial or complete dislocation of the head of the humerus.

Our shoulder specialist

An experienced consultant caring for your shoulder health