Thenar Eminence Pain

[John Knab]

Dear Stephen,

First of all, as a subscriber to your educational website — THANK YOU! It has been incredibly helpful…

Second, Dave Smith said to say hi!

I just posted this case on LinkedIn he suggested that I run it by you…. I’m not sure if I have the diagnosis right….Its near and dear to my heart since the patient is me!!

Here is the case:

RH Dominant male 50 y.o. was taking off an extremely thick/non-compliant pair of socks and while the left thumb was engaged in the process a sudden sharp pain was felt (during hyperextension/abduction). The top scan is the unaffected side. The bottom is the affected (LEFT) side.

Current symptoms include waxing/waning pain only. ROM normal. No instability/loss of strength. No sensory deficits. No muscle wasting/atrophy. Minimal effect on ADL’s QOL. Xrays benign. No MRI. I am still able to play guitar (heavy use of Left thumb) although it is somewhat painful to play.

I have attached the videos.

My guess is that I ruptured the tendon of the superficial head of the FPB — since the bright white structure seen on the TOP PANEL (unaffected side) is completely absent on the LOWER PANEL (affected side).

I cannot find the “stump” of the possibly ruptured tendon, due to my skill level, or the passage of time since the injury. (Like Dave I am an anesthesiologist who learned too late in life that I am an MSK nerd. He’s light years ahead of me!

The injury was probably 6 or 7 years ago. Sx’s no better/No worse since then.

Thanks again for any insight and I look forward to learning more from you as I evolve!

Best Regards,

John

John H. Knab MD
Medical Director
Center for Pain Management
1602 Physicians Dr. Suite 103
Wilmington, NC 28401
(910) 442-1200
http://www.portcitypain.com

Attachments:

You must be logged in to view attached files.

[Stephen Bird]

Hi John,

You have given me some really nice images to review.

I am certain that your superficial head of FPB is normal from these images.

I can see a really nice facial boundary between opponens and the SHFPB and the muscle each side is beautiful and black.

The bright white thing on the other hand is not a tendon of SHFPB but rather just hitting the muscle edge (perimysium) at a skyline angle to make the white blob.

You are just skimming the muscle boundary.

So I am happy with all of the muscles, they are well preserved.

So if the FPL tendon with no inflammation of the radial bursa.

BUT

Your 1st CMC joint has some early arthritis changes and it is asymmetrical with the other side,

There are some sharp little osteophytes seen on the video which I think might play up during guitar sessions.

I am in favour of a diagnosis of a 1st CMC joint capsule injury at the time of trauma and some current overlying OA changes exacerbated by guitar leading to some synovitis and symptoms.

You may not see these changes easily on a plain radiograph.

I have attached some images and highlighted the areas I am talking about.

When you see the changes they may appear subtle but when you compare to the asymptomatic side you will be easily convinced.

Thanks so much for supporting the website, I really appreciate it,

Happy scanning,

Steve

Attachments:

You must be logged in to view attached files.

[Author]

Posts