Triangular Fibro-Cartilage Complex (tears).

Hey guys! This time, I spent a little time writing up a bit of a primer on the Triangular Fibro-Cartilage Complex of the wrist and its various injuries, as it is generally implicated in many occupationally and ADL driven injuries of the forearm, wrist, and hand. Hopefully, this helps someone out there!

https://drive.google.com/file/d/0B8LIRxTW4b74azBkZGdNc1B3SG8/view?usp=sharing

-Dan

Scaphoid Fractures.

Hey guys! Another little write up for the week, this time on scaphoid fractures - a VERY important fracture for OTs to understand. As you can tell, I am a pretty firm believer in the use of radiology in therapy, so you'll be seeing a little bit more of that in this discussion. Hopefully, this helps at least give some of you food for thought.

https://drive.google.com/file/d/0B8LIRxTW4b74b01QSkVFZ0NWZ2c/view?usp=sharing

And the QA so far:

Dan,

That was a really fun post to read. I really liked your use of the "over the skin" visualization of the scaphoid. It makes a lot more sense, mechanically, when thinking about why it fractures when you fall. I also really liked that you referenced Cynthia Cooper's book. It is a great book to have. 

What I wanted to ask you, and the group, is about the palpation of the scaphoid in the anatomic snuffbox when testing for fracture. I know it has good sensitivity measures but whenever I attempt to do that test, it ALWAYS elicits pain. And that is whether patients have a scaphoid fracture or not. In my mind, I feel like this is a mediocre test because the dorsal radial sensory nerve is right there in the snuffbox and we are just compressing that nerve and causing pain.

If you look that the picture, while not entirely accurate as there are most likely variations of such, the bifurcation of the dorsal radial sensory nerve is right at the location of the scaphoid where we would be palpating. So am I just doing the palpation in the wrong place or am I just hitting the nerve producing a false positive? Am I totally off with the anatomy? Right now I have a patient who had this nerve repaired along with his ECRB. And it is so hypersensitive. Good excursion of his ECRB though.

What are your thoughts?

-      Sean

Sean,

I don’t think you’re off at all. I do think, however, that the devil may lie with the lack of detail for the type of pain felt during the special testing for scaphoid fractures. I remember thinking the same exact thing when I had first learned of this test, and then again when I wrote this post – if you press on it just right, you definitely do feel that dull, transient, vaguely radiating pain of that is characteristic of compression neuralgia. This is doubly true because the dorsal radial sensory nerve into the hand refers pain into the snuffbox and onto the dorsal aspect of the first innerossei!

However, I think with pain being the lowest common denominator, it is important to differentiate compression nerve pain from bone pain. As mentioned before, compressive nerve pain (often seen in tunnel disorders and radicular neuralgias from a soft tissue inflammation etiology such as from acute whiplash injuries) tends to feel dull, transient and radiating; occasionally has bursts of lancinating pain and can be reproduced with palpation by pinning the nerve against a nearby bone. Bone pain for fractures is VERY sharp, jagged, and from what I hear often from patients, a feeling that “something is direly wrong”. On the other hand, malignant bone pain is unmistakably deep and achy, almost like growing pains you once felt as a kid.

I’d also wager a guess and say that the inflammation present for a scaphoid fracture (between protective edema, bone marrow edema, soft tissue inflammation, etc.) would also help separate it from a nerve dysfunction, as while nerves themselves can become inflamed, this often cannot be detected via palpation or surface anatomy…certainly not so with a nerve as small as the dorsal radial sensory nerve.

As for your patient, I’m sure you’re right on the money with differentiating the hypersensitivity of the nerve from the ECRB recovering. When nerves are damaged (even intentionally via repair), the first thing they lose is the ability to perceive pain and light touch…and the last thing to generally recover is also pain and light touch. As the nerve recovers those senses, the signals from the nerve picked up by the CNS are poorly modulated at the brain (and then by the descending pathways) and are perceived as hypersensitive to touch and with bouts of knifelike pain. It sounds like you’re right with the dorsal radial sensory nerve being hypersensitive – time to bust out the sensory re-ed stuff (which I’m sure you already have) for textured light touch and noxious stimuli to the first innerossei or distal C6 dermatome.

-Dan

Dan,

I have learned a lot about scaphoid fractures after performing research for my post on avascular necrosis (AVN) and reading your post.  I read an article by Lok, Griffith, Ng, and Wong (2014) that collaborates your statement about radiographs not being perfect, and if the patient is presenting with clinical signs of a fracture, a MRI is warranted. The authors give a figure of 15-20 as the percentage of isolated scaphoid fractures that do not show-up on a radiograph.  I can understand that if those fractures are left undetected, they can lead to more severe complications such as AVN.  I am going to mention the same information that I stated in my post related to gadolinium-enhanced MRI and would like your input.  The authors mention that fatty marrow signal can remain in the presence of AVN and sometimes can also be present in the absence of AVN and they argue that T1-hypointensity of the marrow should not be considered a reliable diagnostic tool for scaphoid AVN (Lok, et al., 2014).   Their recommendation is to perform gadolinium-enhanced MRI as a reliable diagnostic tool.  I did not see any mention of using a contrast medium during MRI in your post.  Did you find any literature on this and what are your thoughts about the reliability of unenhanced MRI in those cases where the fatty marrow signal might be atypical?

Thanks as always for allowing me to learn from your post.

-Chris

Reference

Lok, R. L. K., Griffith, J. F., Ng, A. W. H., & Wong, C. W. Y. (2014). Imaging of radial wrist pain. Part II: Pathology. Skeletal

Radiology, 43, 725-743. doi: 10.1007/s00256-014-1826-5

Chris,

Thank you to being so receptive to my ramblings : ) You know, I did indeed find some mention that MRI is not the wholly reliable tool, by itself, that the Agustsson description indicated. I am struggling to find where I had read this as I flip through some of my books here. I did not, however, seem to find anything about Gadolinium dye enhanced MR for the scaphoid – it would make complete sense of why it would make the a T1 MR so much more sensitive. Agustsson himself mentions that MRI poorly detects fracture lines in scaphoid fractures due to the presence of bone edema “clouding” the site of fracture…the images I seemed to have found were much more cleanly cut, suggesting the possibility that these fractures may have been “older” as fracture lines for scaphoid fractures remain visible even after bone healing is complete. I’m going to go read that Lok et. al. article now, thank you for pointing me into the right direction!

-Dan

Ulnar variance (or why you'll need your goniometer for wrist pain)

Hey again, guys. I just wanted to provide you guys a short write up on ulnar variance. Ulnar variance, in a nutshell, is a measurement of how evenly the distal ulnar head and distal radial head line up to each other - it is an integral thing to measure for anyone with acute or chronic wrist pain, and it's easy to do with a gonimeter. Changes in variance as highly suggestive of specific disease and dysfunctions that either dramatically alter our POCs and outcomes, may prompt differential diagnosis, or may require immediate referral back to the referring physician. Take a look and hopefully you'll get something out of this! More to come!

-Dan

https://drive.google.com/file/d/0B8LIRxTW4b74aHRITDBvQ3dxcFE/view?usp=sharing

Lateral Epicondyalgia - a rant and some talking points

Hey guys! As some of you may or may not know, I am pretty involved in the research community as through Fellowships through both the American Society of Shoulder and Elbow Therapists and the American Academy of Pain Management. I am often tasked with leading and contributing to discussion with my peers about a whole lot of...well, stuff, in order to share thoughts, sources, and opinions for each other's research.

A discussion about lateral epicondylagia (tennis elbow) came up, which is a condition any OT should be pretty familiar with. I had quite a lot to say on it's often underwhelming management by both rehab professionals and doctors based upon our science's poor understanding of its nature. I wanted to share with you the thoughts, as well as answers to a couple questions by my peers, that I had on it.

Link to the document:
https://drive.google.com/file/d/0B8LIRxTW4b74cENVUThMNTBzdVE/view?usp=sharing

I'll try to keep these up, if anyone is interested in my rambling. As more questions come in, I'll post them here.

-Dan