Human Anatomy Vol 1

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UPPER LIMB

Fig. 10.17: Golfer's elbow

Fig. 10.18: Normal, cubitus valgus, and cubitus varus

Features

Type

Articular surfaces

Ligaments

Blood supply

Nerve supply

Movements

Feotules

The radius and the ulna are joined to each other at

the superior and inferior radioulnar joints. These are

described in Table 10.2. The radius and ulna are also

connected by the interosseous membrane which

constitutes middle radioulnar joint (Fig. 10.19).

INTEROSSEOUS MEMBRANE

The interosseous membrane connects the shafts of the

radius and ulna. It is attached to the interosseous

borders of these bones. The fibres of the membrane run

downwards and medially from the radius to ulna

(Fig. 10.19). The two bones are also connected by the

oblique cord which extends from the tuberosity of the

radius to the tuberosity of the ulna. The direction of its

fibres is opposite to that in the interosseous membrane.

1 Superiorly, the interosseous membranebegins 2-3 cm

below the radial tuberosity. Between the oblique cord

and the interosseous membrane there is a gap for

passage of the posterior interosseous vessels to the

back of the forearm.

2 Inferiorly, a little above its lower margin, there is an

aperture for the passage of the anterior interosseous

vessels to the back of the forearm.

3 The anterior surface is related to the flexor pollicis

longus, the flexor digitorum profundus, the pronator

quadratus, and to the anterior interosseous vessels

and nerve (see Fig.2.25).

4 The posterior surface (seeFig.9.55) is related to the

supinator, the abductor pollicis longus, the extensor

pollicis brevis, the extensor pollicis longus, the

extensor indicis, the anterior interosseous artery and

the posterior interosseous nerve.

Thble 10.2: Badioulnar ioints (Fig. 10.19)

Superior radioulnar joint lnferior radioulnar ioint

Pivot type of synovial joint Pivot type of synovial joint

. Circumference of head of radius ' Head of ulna
'.
Osseofibrous ring, formed by the radial notch of ' Ulnar notch of radius
the ulna and the annular ligament
. The annular ligament. lt forms four-fifths of the ring. The capsule surrounds the joint. The weak upper
within which the head of the radius rotates. lt is part is evaginated by the synovial membrane
attached to the margins of the radial notch of the to form a recess (recessus sacciformis) in front
ulna, and is continuous with the capsule of the of the interosseous membrane
elbow joint above
. The quadrate ligament, extends from the neck of. The apex of triangular fibrocartilaginous articular
the radius to the lower margin of the radial notch of disc is attached to the base of the styloid
the ulna process of the ulna, and the base to the lower
margin of the ulnar notch of the radius (Fig. 10.20)
Anastomoses around the lateral side of the elbow Anterior and posterior interosseous arteries
joint
Musculocutaneous, median, and radial nerves Anterior and posterior interosseous nerves
Supination and pronation Supination and pronation