Finger Flexion

Electrode Placement
Application Instruction by Dr. Lucinda Baker

Electrode placement for isolated finger flexion. The negative electrode is placed more distally on the forearm where the finger flexors exit from under the wrist flexors. The positive electrode is placed over the tendinous portion of the flexor surface.

Finger Flexion

Video Instruction
Audio Transcript:

Electrode placement for isolated finger flexion. The negative electrode is placed more distally on the forearm where the finger flexors exit from under the wrist flexors. The positive electrode is placed over the tendinous portion of the flexor surface.

During stimulation you will note range of motion into flexion at the metacarpal phalangeal, the distal interphalangeal, and the proximal interphalangeal joints. This would be graded a three out of five contraction.

Finger Flexion

Muscle Anatomy

Muscles involved in finger flexion:

Flexor Digitorum Profundus
Origin: Upper ¾ of the anterior and medial surfaces of the body of the ulna, interosseous membrane and deep fascia of the forearm
Insertion: Base of the distal phalanges of the fingers
Other actions: Flexes distal and proximal interphalangeal joints

Flexor Digitorum Superficialis
Origin: Medial epicondyle of the humerus (common flexor tendon) as well as parts of the radius and ulna
Insertion: Anterior margins on the base of the middle phalanges of the four fingers

Flexor Pollicis Longus
Origin: The middle ½ of the anterior surface of the radius and the adjacent interosseous membrane
Insertion: The base of the distal phalanx of the thumb

Finger Flexion

Nerve Anatomy

Nerves involved in finger flexion:

Flexor Profundus Digitorum
Nerve innervation: The medial aspect of the muscle (which flexes the 4th and 5th digit) is supplied by the ulnar nerve
The lateral aspect (which flexes the 2nd and 3rd digit) is innervated by the median nerve specifically the anterior interosseous branch
Nerve root: C8, T1

Flexor Digitorum Superficialis
Nerve innervation: Median nerve
Nerve root: C8, T1

Flexor Pollicis Longus
Nerve innervation: Anterior interosseous nerve (branch of median nerve)
Nerve root: C8, T1