LAST CHANCE: X-ray Interpretation: Elbow Injuries - Half price course offer ends this Sunday!

Accessory abductor digiti minimi

Case contributed by Dr Maulik S Patel


Bilateral wrist dorsal nodular swelling for 2-3 years.

Patient Data

Age: 30 years
Gender: Female

Normal-appearing ulnar artery and nerve in Guyon’s canal.  There is an extra structure in left tunnel showing muscle echotexture. It is separating the ulnar nerve from the artery, which normally run in unison. Ulnar artery is patent.

Ultrasonography also showed bilateral scapholunate joint-related ganglia (images not shown).

Case Discussion

The patient's wrist swelling was accounted for by dorsal wrist ganglia.

An accessory abductor digiti minimi muscle was demonstrated in Guyon's canal. There is no symptom of ulnar neuropathy in Guyon's canal due to the presence of an accessory muscle.

The accessory abductor digiti minimi is the most common accessory muscle of the hand, occurring in up to 25% of the population.

PlayAdd to Share

Case information

rID: 45533
Published: 29th May 2016
Last edited: 14th Aug 2019
Inclusion in quiz mode: Excluded

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.