Content Reviewers:Yifan Xiao, MD
Klumpke’s palsy, named after the neuroanatomist Augusta Déjerine-Klumpke who first described it, is when there is muscle paralysis in the hand, caused by nerve damage. This causes all the fingers to stay in a flexed position so it’s also called “total claw hand.”
Now, some of the cervical and thoracic nerves form the brachial plexus, which is a network of nerves that controls the muscles and sensations in the shoulder, arm, and hand.
The five roots combine to form three trunks: C5 and C6 merge to form the superior or upper trunk, C7 remains as the middle trunk, and C8 and T1 merge to form the inferior or lower trunk.
These trunks then form six divisions, which will regroup with each other to form three cords.
These cords give off five terminal branches.
The main three are the median nerve - which is made up of contributions from C5, C6, C7, C8, and T1 - the radial nerve, which is made up of contributions from C5, C6, C7, C8, and T1, and finally, the ulnar nerve, which is made up of contributions from C8, T1, and occasionally C7.
Klumpke’s palsy occurs when there’s a stretch or tear at the the C8 or T1 roots, or at the lower trunk. This happens when an abducted arm is pulled further away from the body.
In infants, this could happen when the baby is pulled out of the birth canal by the arm during delivery.
In adults a trauma to the shoulder, like when someone tries to grab a tree branch while falling, can cause the nerves to be torn. This leads to dysfunction of the median and ulnar nerves since they contain fibers from these roots.
So when the ulnar nerve is damaged, it causes the wrist to stay extended.
Similarly, the ulnar nerve supplies the hypothenar muscles, which control the little finger, and the interossei muscles, which abduct and adduct the fingers, meaning to spread or bring them together.
On the contrary, muscles of the forearm opposes the action of the lumbricals. These muscles include flexor digitorum profundus, which flexes the fingers at the interphalangeal joints, and extensor digitorum, which hyperextend them at the metacarpophalangeal joint.
So, with klumpke’s palsy, we end up with a person who’s forearm is stuck in the supinated position, with the wrist extended. The fingers are flexed at the interphalangeal joints, and can’t abduct or adduct.
- "Robbins Basic Pathology" Elsevier (2017)
- "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
- "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
- "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
- "Histopathological basis of Horner's syndrome in obstetric brachial plexus palsy differs from that in adult brachial plexus injury" Muscle & Nerve (2008)
- "Fractured clavicle and Erb's palsy unrelated to birth trauma" American Journal of Obstetrics and Gynecology (1997)