What to do with a thumb dislocation?

June 7, 2013

Hand XR, Orthopedics, Trauma, XR


This patient presented with thumb pain after an MVC:thumb mcp 2thumb mcp3

The xray shows a dorsal dislocation at the thumb MCP joint, some fragments concerning for avulsion fractures as well.  The mechanism was likely hyperextension from the steering wheel.  It is important to note that this type of injury is almost always associated with complete disruption of the volar plate and is often associated with collateral ligamentous injury.  This results in an unstable MCP joint even after reduction.  The thumb MCP is a very important joint and instability can lead to decreased pincher grasp function causing significant morbidity long-term.   Operative indications according to Wheeless’ Textbook of Orthopedics include:

1.  Inability to reduce

2.  Radial or ulnar instability >40 degrees after reduction (stress xray views can help quantitate)

3.  Fracture through the sesamoids

Thumb MCP dislocation

We had good success reducing this after a median nerve block.  Clinically the joint was very unstable with stress angles nearing 60 degrees.  The patient was placed in a thumb spica splint and referred to hand surgery.

Author:  Russell Jones, MD

References:

1.  Dislocations of the Thumb MP Joint. Wheeless’ Textbook of Orthopedics online.  http://www.wheelessonline.com/ortho/dislocations_of_the_thumb_mp_joint  Accessed: 5/2013

Advertisements

About emrems411

EMREMS: Radiology in Emergency Medicine

View all posts by emrems411

Subscribe to EMREMS

Subscribe to our RSS feed and social profiles to receive updates.

2 Comments on “What to do with a thumb dislocation?”

  1. docskalski Says:

    Thanks again for the cases! For repayment, here is an “enhanced” version of your logo if you want to use it: http://corticalmedia.files.wordpress.com/2013/06/emrems.jpg

    Reply

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: