anatomy

1. The sternoclavicular joint
&
The Acromioclavicular joint

2. The sternoclavicular joint
• The Sternoclavicular joint is a saddle type of
synovial joint between the sternal end of
clavicle & the manubrium of sternum with the
articulation of 1st costal cartilage.
• It is structurally classed as a synovial
saddle joint and functionally classed as a
diarthrosis and multiaxial joint.

4. Articular cartilage and Disc
The articular surfaces are covered with fibro-cartilage.
The joint is separated into two compartments by a
fibro-cartilaginous articular disc.

5. Ligaments of SC joint
• There are three major ligaments present in the
Sternoclavicular joint.
• Posterior and anterior sternoclavicular ligament.
• Interclavicular ligament.
• Costoclavicular ligament.

10. Dislocation of sternoclavicular joint

12. Acromioclavicular joint

13. The Acromioclavicular joint
• The Acromioclavicular (AC) joint is a plane type
of synovial joint taking place in between the
acromion of scapula and the clavicle.
• It has two atypical features :
• The articular surfaces of the joint are lined with
fibrocartilage (as opposed to hyaline cartilage).
• The joint cavity is partially divided by an
articular disc.

14. Features of Acromioclavicular joint
• Articular surface
• Articular disc & joint
cavity
• Fibrous capsule
• ligaments

15. The Acromioclavicular joint
• Ligaments :
• There are three major ligaments present in
the acromioclavicular joint.
• Acromioclavicular ligament
• Conoid ligament
• Trapezoid ligament

17. Neurovascular Supply –
• Vessels :
• The arterial supply to the joint is via two vessels.
• Suprascapular artery
• Thoraco-acromial artery
• Nerves :
• The acromioclavicular joint is innervated by
articular branches of the suprascapular and
lateral pectoral nerves. They both arise
directly from the brachial plexus.

18. • Movements of the joint
• The AC joint allows a degree of axial rotation
and anteroposterior movement.

21. • Injuries of the joint
• Dislocation of the clavicle
• Sprains
• Fractures
• Degenarative arthritis

22. Sprain of AC joint