anatomy of Radio ulnar joint

hey this is vedika agrawal
this presentation is to easily understand anatomy of radio ulnar joint.
the topics are made easily understand throug diagrams.
reference book : BD Chaurasia

1. RADIO-ULNAR JOINT PREPARED BY – Vedika Agrawal (BATCH 2019-20) ROLL NUMBER – 98 GUIDED AND MOTIVATED BY – Dr. Priya Mehta MGM ALLIED HEALTH SCIENCE INSTITUTE, INDORE

2. Introduction Pivot joint Types of joint Interosseous membrane Movements Clinical anatomy Contents

3. The radius and ulna joined to each other at superior and inferior radio-ulnar joints. The joint provides pivot variety of movement. It is responsible for pronation and supination of forearm. INTRODUCTION

4. PIVOT JOINT It is also called trochoid joint. Articular surface comprises of a central bony pivot (peg) surrounded by an osseocartilaginous ring. Movements are permitted in one plane around a vertical axis. Its seen in radio-ulnar as well as in atlanto-axial joint.

5. Superior radioulnar joint Inferior radioulnar joint Medial radioulnar joint TYPES OF RADIOULNAR JOINT

6. Articular surface head of radius radial notch of Ulna Ligaments Annular ligament - it cover 4/5th of Osseo-fibrous ring, within the head of radius rotates .It is attached to margins of the radial notch of ulna and continuous with capsule of elbow joint. Quadrate ligament - it extends from neck of radius to lower margin of radial notch of ulna Nerve supply - Musculocutaneous, median, and radial nerve Blood Supply - Anastomoses around the lateral side of the elbow join. Superior radioulnar joint

7. Articular Surface Head Of Ulna Ulnar Notch Of Radius Ligaments The capsule surrounds the joint. Upper weak part is enavigated by the synovial membrane to form a recess in front of interosseous membrane. The apex of triangular fibro cartilaginous articular disc is attached to the base of the styloid process of the ulna, and the base to the lower margin of the ulnar notch of the radius. Blood supply - Anterior and posterior interosseous arteries Nerve supply - Anterior and posterior interosseous nerve . INFERIOR RADIOULNAR JOINT

8. MEDIAL RADIOULNAR JOINT It is syndesmosis type fibrous joint. Articular Surface joined by interosseous membrane attached to interosseous borders of radius and ulna . It is attached to posterior border of medial surface at lower end of radius .

9. INTEROSSEOUS MEMBRANE The interosseous membrane connects the shaft of the radius and ulna. The fibers of the membrane run downwards and medially from radius to ulna . Superiorly - it begins 2-3 cm below the radial tuberosity . Inferiorly - a little above its lower margin. Anterior surface - it is related with flexor compartment of forearm. Posterior surface - it is related with extensor compartment of forearm . These two bones also connected by the oblique cord which extends from the tuberosity of the radius to the tuberosity of the ulna. (Direction of fibers is opposite to interosseous membrane.)

10. Functions Of Interosseous Membrane It binds the radius and ulna to each other . it provides attachments to many muscles . it transmits forces applied to the radius (through hand) to the ulna . separates the forearm into flexor and extensor compartment.

11. SUPINATION In a semi flexed elbow , the palm is turned upwards. Supination is more powerful than pronation because it is an anti-gravity movement. It is brought about by following muscles – supinator biceps brachii Trick to learn --- beggars always supinate….

12. PRONATION In a semi flexed elbow the palm is turned downwards. During pronation head of radius spins within annular ligament. As radius comes medially across the lower part of ulna. Pronation is brought about following muscles – Pronator quadratus Pronator teres Trick to learn --- kings always pronate…

13. Clinical Anatomy Around 50% of supination and 50% of pronation are generally required to perform many of the routine activities. Its movement may also be lost due to disuse atrophy or paralysis of upper limb. It can be bought back to normal thorough physiotherapeutic exercises and machines like pronation supination manual device and pronation supination CMP device respectively. During supination radius and ulna are parallel to each other . During Pronation , radius crosses over the ulna. In synostosis (fusion) of upper end of radius and ulna , Pronation is not possible.