Wrist Extension

Electrode Placement
Application Instruction by Dr. Lucinda Baker

Electrode placement for isolated wrist extension stimulation. The lateral condyle is marked with the X, and the negative electrode is placed just distal to that marking. The positive electrode is placed over the tendinous area of the forearm.

Related Electrode Placements

Wrist Extension

Video Instruction
Audio Transcript:

Electrode placement for isolated wrist extension stimulation. The lateral condyle is marked with the X, and the negative electrode is placed just distal to that marking.

The positive electrode is placed over the tendinous area of the forearm. The stimulated contraction can be seen to be dominantly wrist extension with minimal finger extension and would be graded three out of five muscle grade.

Wrist Extension

Muscle Anatomy

Muscles involved in wrist extension:

Extensor Carpi Radialis Longus (ECRL)
Origin: Just distal to the brachioradialis at the lateral supracondylar ridge of the humerus, the lateral intermuscular septum and by a few fibers at the lateral epicondyle of the humerus
Insertion: Posterior base of the 2nd metacarpal
Other actions: Abducts the hand

Extensor Carpi Radialis Brevis (ECRB)
Origin: Humerus at the anterior lateral epicondyle (common extensor tendon)
Insertion: Posterior base of the 3rd metacarpal
Other actions: Abducts the hand

Extensor Carpi Ulnaris (ECU)
Origin: Lateral epicondyle of the Humerus. Ulnar head: Olecranon, Posterior surface of ulna, antebrachial fascia
Insertion: 5th metacarpal

Extensor Digitorum (ED)
Origin: Lateral epicondyle (common extensor tendon)
Insertion: Extensor expansion of middle and distal phalanges of the 2nd, 3rd, 4th and 5th fingers
Other actions: finger extension

Wrist Extension

Nerve Anatomy

Nerves involved in wrist extension:

Extensor Carpi Radialis Longus (ECRL)
Nerve innervation to the muscle - Radial nerve
Nerve roots: C6, C7

Extensor Carpi Radilis Brevis (ECRB)
Nerve innervation to the muscle: Deep branch of the radial nerve
Nerve roots: C7, C8

Extensor Carpi Ulnaris (ECU)
Nerve innervation: Deep branch of the radial nerve
Nerve roots: C7, C8

Extensor Digitorum (ED)
Nerve innervation to the muscle: posterior interosseous nerve
Nerve roots: C7, C8