Proximal Radioulnar Joint

Front 1

TYPE
DEGREES OF FREEDOM

Back 1

synovial pivot joint
one degree of freedom

Front 2

ARTICULATING SURFACES

Back 2

cylindrical head of radius (240 covered with hyaline cartilage)
ring formed by radial notch of ulna and annular ligament

Front 3

STABILITY

Back 3

stable joint
annular ligament is narrower inferiorly so holds head of radius in place

Front 4

LIGAMENTS

Back 4

ANNULAR LIGAMENT

- runs around the head of the radius from the anterior to the posterior border of radial notch of ulna
- thinly covered with hyaline cartilage where it runs around the head of the radius
- fibrous capsule of the elbow is attahced to its superior border

QUADRATE LIGAMENT

- runs from neck of radius to inferior margin of radial notch of ulna
- supports synovial membrane between radius and ulna
- fibres criss-cross, some fibres being taut throughout all phases of pronation/supination

Front 5

SYNOVIAL MEMBRANE

Back 5

- extends below annular ligament and articular margin of head of radius as sacciform recess
- proximal radioulnar joint cavity is continuous with that of the elbow superiorly

Front 6

NERVE SUPPLY

Back 6

median
ulnar
radial

Front 7

MOVEMENTS

Back 7

pronation
supination