Lumbrical Grip

Electrode Placement
Application Instruction by Dr. Lucinda Baker

Electrode placement for lumbrical grip. The ulnar nerve is stimulated as it enters the hand using the negative electrode just proximal to the wrist. The positive electrode is placed over the tendinous surface of the flexor forearm.

Lumbrical Grip

Video Instruction
Audio Transcript:

Electrode placement for lumbrical grip. The ulnar nerve is stimulated as it enters the hand using the negative electrode just proximal to the wrist. The positive electrode is placed over the tendinous surface of the flexor forearm.

Stimulation results in activation of the lumbricals and many of the interossei, resulting in metacarpal phalangeal flexion, some thumb adduction, as well as activation of the hypothenar eminence.

Lumbrical Grip

Muscle Anatomy

Lumbrical muscles involved in Lumbrical Grip:

1st Unipennate
Origin: It originates from the radial side of the most radial tendon of the flexor digitorum profundus
Insertion: it passes posteriorly along the radial side of the index finger to insert on the extensor expansion near the metacarpophalangeal joint.

2nd Unipennate
Origin: It originates from the radial side of the second most radial tendon of the flexor digitorum profundus
Insertion: It passes posteriorly along the radial side of the middle finger and inserts on the extensor expansion near the metacarpophalangeal joint.

3rd Bipennate
Origin: One head originates on the radial side of the flexor digitorum profundus tendon corresponding to the ring finger, while the other originates on the ulnar side of the tendon for the middle finger.
Insertion: The muscle passes posteriorly along the radial side of the ring finger to insert on its extensor expansion.

4th Bipennate
Origin: One head originates on the radial side of the flexor digitorum profundus tendon corresponding to the little finger, while the other originates on the ulnar side of the tendon for the ring finger.
Insertion: The muscle passes posteriorly along the radial side of the little finger to insert on its extensor expansion.

Lumbrical Grip

Nerve Anatomy

Lumbrical nerves involved in Lumbrical Grip:

First and Second Lumbrical (The Most Radial)
Nerve innervation: Median nerve

Third and Fourth Lumbrical (The Ulnar Two)
Nerve innervation: Ulnar nerve