Flexor Carpi Ulnaris

General information

A fusiform muscle situated in the anterior forearm. It is one of the superficial forearm flexors, along with the pronator teres, palmaris longus, flexor digitorum superficialis and flexor carpi radialis muscles.

Literal meaning

The muscle on the ulnar side that bends the wrist.

Interesting information

Flexor carpi ulnaris is the most medial of this group and as well as flexing the wrist with the flexor carpi radialis and adducting the wrist with the extensor carpi ulnaris, which can be done at the same time. The flexor carpi ulnaris is the only anterior compartment muscle that receives full innervation from the ulnar nerve.

Origin

Medial epicondyle of humerus, olecranon and posterior border of ulna.

Insertion

Pisiform bone, hamate bone, base of 5th metacarpal bone.

Function 

Wrist joint: Wrist flexion, wrist adduction.

Nerve supply

Ulnar nerve (C7-T1).

Blood supply

Posterior ulnar recurrent artery, ulnar artery.

Relevant research

Cubital tunnel syndrome occurs when the ulnar nerve is trapped and compressed in between both heads of the Flexor Carpi Ulnaris Aponeurosis, this occurs at the cubital tunnel and is a common upper limb compression neuropathy.

Flexor carpi ulnaris tendinopathy, an overuse injury, presents with ulnar sided wrist pain and is brought on during wrist flexion and ulnar deviation.

Lung BE, Siwiec RM. 2019. Anatomy, Shoulder and Upper Limb, Forearm Flexor Carpi Ulnaris Muscle. Available from: https://www.ncbi.nlm.nih.gov/books/NBK526051/

Flexor carpi ulnaris exercises

Wrist pain associated with Flexor Carpi Radialis Tendinopathy can be improved through a 12 week eccentric training of the forearm muscle.

Knobloch, K., Spies, M., Busch, K. H., & Vogt, P. M. (2007). Sclerosing therapy and eccentric training in flexor carpi radialis tendinopathy in a tennis player. British journal of sports medicine, 41(12), 920–921.

Strengthening:

Eccentric wrist flexion

Rest your arm on a table with your hand hanging off the end and with your palm facing up. Hold a light dumbbell and lift your hand towards the ceiling using your other hand. Then slowly and in a controlled fashion, let the weight take your hand back down to neutral. At the bottom, repeat the sequence again

Stretching:

Wrist flexion stretch with internal rotation

Holding the palm of your hand, push your hand downwards and towards the little finger side to create a stretch.