The Value of High Quality MRI Imaging for Acute Injuries of the Thumb

May 25, 2010 - PRLog -- Acute thumb injuries / sprains are a common injury either in the bike park or in alpine and nordic skiing.  Initially, definitive diagnosis may be challenging given extreme pain, tenderness and negative radiographs.  Accurate diagnosis is critical in the early stage which would determine conservative versus surgical therapy. High field (1.0 Tesla or greater) MRI imaging, especially in a MSK dedicated magnet, can give very accurate diagnosis of the ligaments, the tendons and bony structures of the thumb.  This can be centered on the IP, MCP or carpal metacarpal joint. The typical injury is usually a sprain of the ulnar collateral ligament of the first metacarpal phalangeal joint, but less likely we may also see injuries of the first carpal metacarpal joint.

History: This is an atypical presentation of a sprain of the base of the thumb.  This is a case of a physiotherapist who, while manipulating a patients spine, hyperextended the thumb with acute pain at the deep base of the thumb into the thenar eminence.  Initial physical examination demonstrated acute pain, tenderness and swelling, which was exacerbated in abduction or extension of the thumb. To view the images referenced please visit:  http://www.whistlermri.com/Doctors/October2009MRIInsight/...

Image 1 - This is a coronal IR (fat suppressed) image of the thumb, with emphasis on the base of the thumb and the first carpal metacarpal joint.
This image shows (long arrow) an attenuated proximal ulnar collateral ligament of the first CMC joint with increased fluid within and around and joint.  Also (short arrow), there is bone marrow edema at the base of the first metacarpal on the ulnar side.  In addition the joint is subluxed radially.

Image 2 - This is a coronal GRE sequence (high resolution sequence for ligament and cartilage) of the base of the thumb.
This image also centered on the first CMC joint demonstrates a small bony fragment (long arrow) at the ulnar side of the first CMC joint.  This represents an avulsion fracture of the base of the first metacarpal on the ulnar side (short arrow).
 
Image 3 - Sagittal IR (fat suppressed) sequence at the level of the radiocarpal joint.
The scaphoid bone is normal (single short arrow).  However, incidental note is made of a large complex ganglion cyst (set of 3 arrows) off the volar aspect of the radial scaphoid joint.  This is deep to the flexor carpi radialus (long arrow)

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Whistler MRI clinic is the west coasts only independent “extremity dedicated” imaging facility using a high field, full strength 1.0T MRI scanner. We are located in beautiful Whistler, British Columbia. Our ONI MRI scanner for arms and legs delivers high definition diagnostic images for accurate diagnosis of a full range of injuries and medical conditions, helping you get back to work, play and enjoying life!