Unhappy Triad Knee Injury

This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.
Eudjinn

Eudjinn

Full Member
15+ Year Member
Joined
Oct 6, 2007
Messages
535
Reaction score
2
FA 2010 now states that this is damage to the MCL, ACL and LATERAL (not medial) meniscus...

Am I correct to say that we have been taught for the past 2 years that this is MCL, ACL and MEDIAL meniscus...?

It doesn't seem like a mistake since FA takes the time to bold "not medial"
Members don't see this ad.
 
Sort by date Sort by votes
Wtf is wrong with FA? I hate how it is full of errors. That is really misleading.

Edit: I guess they are right. But still, they are full of errata!
 
Last edited:
Upvote 0 Downvote
good find on wiki... i actually checked this same thing on wiki a month or two ago and it was still saying medial meniscus (which is why I was still unsure). now it seems to be up to date and I can now safely assume that this is the new definition.
 
Upvote 0 Downvote
Members don't see this ad :)
what will be the correct answer on the boards. i mean i doubt that the NBME takes all the old terrible triad questions out of the banks immediately. it is a pretty common question asked too so i will probably freak out if i see it on the step in june and not know which answer to choose.
 
Upvote 0 Downvote
The NBME is pretty on-board with these changes, but I guess I can't say for sure. I've been working on UW along with FA, and I think they have the "updated" unhappy triad scenario, as I don't remember questioning FA (my anatomy is super weak, so I didn't even remember the original one). I'll post it up here if I find anything on the flipside.
 
Upvote 0 Downvote
The MCL is attached to the medial meniscus. Doesn't make sense for the lateral meniscus to go when the MCL goes.
 
Upvote 0 Downvote
engineeredout said:
The MCL is attached to the medial meniscus. Doesn't make sense for the lateral meniscus to go when the MCL goes.
Click to expand...

Whether it makes sense or not, it's been shown in a study that that's the way it happens more frequently (lateral > medial meniscus with MCL + ACL injury).
 
Upvote 0 Downvote
I definitely had a recent unhappy triad question come up and the answer was still listed as medial lemniscus. We even had a professor make a point to email the class and tell us that FA was wrong. This is going to be interesting to see how fast the USMLE is updated.
 
Upvote 0 Downvote
Upvote 0 Downvote
Members don't see this ad :)
HopefulDoc1984 said:
do you have to citation for the article you are referring to?
Click to expand...

Am J Sports Med. 1991 Sep-Oct;19(5):474-7.
The O'Donoghue triad revisited. Combined knee injuries involving anterior cruciate and medial collateral ligament tears.

Shelbourne KD, Nitz PA.
Methodist Sports Medicine Center, Indianapolis, Indiana 46202.
Comment in:

We identified 60 consecutive patients with combined anterior cruciate and medial collateral ligament (ACL-MCL) disruptions that were incurred during athletic endeavors. Each underwent acute reconstruction of the ACL. The arthroscopic data obtained at the time of reconstructive surgery was reviewed in order to determine the incidence of O'Donoghue's triad (the "unhappy triad"), consisting of ACL, MCL, and medial meniscus tears. Patients were subdivided into two groups for analysis based upon the degree of MCL injury at time of presentation (Group I, 35 patients with a second-degree sprain; Group II, 25 patients with a complete, or third-degree injury). Medial meniscus tears were an uncommon finding. Lateral meniscus tears significantly out-numbered medial meniscus tears in both groups, occurring in 25 (71%) of Group I patients and 8 (32%) of those in Group II. Even chondral fractures of the lateral femoral condyle outnumbered medial meniscus tears [6 (17%) versus 4 (11%)] in patients with a second-degree MCL sprain. Furthermore, when present in Group I patients, tears of the medial meniscus were associated with a concomitant lateral meniscus injury. Group II patients were more likely (60%) than Group I not to have any meniscal abnormality at all. We conclude that the classic O'Donoghue triad is, in fact, an unusual clinical entity among athletes with knee injuries; it might be more accurately described as a triad consisting of ACL, MCL, and lateral meniscus tears. This injury combination appears to be more common when an incomplete, or second-degree, tear of the medial collateral has occurred.(ABSTRACT TRUNCATED AT 250 WORDS)














The odd thing, though, is that many current anatomy and ortho texts still refer to it as MCL, ACL, MM. 1991 isn't exactly 'recent.' Also, they conclude that the classic triad isn't as common, but not necessarily that it has been renamed. Confusing...
 
Upvote 0 Downvote
Ableton said:
This is the way I've always used to identify what gets torn. But by using this method, it is not entirely clear how the lateral meniscus is damaged more often than the medial meniscus.
Click to expand...


Maybe I'm just stupid but I've always just assumed the angulation between the femur and tibia naturally lead to a destruction of the LM (I just always pictured it as "crushing" the LM, and that picture illustrates is quite well).
 
Upvote 0 Downvote
GuyWhoDoesStuff said:
Maybe I'm just stupid but I've always just assumed the angulation between the femur and tibia naturally lead to a destruction of the LM (I just always pictured it as "crushing" the LM, and that picture illustrates is quite well).
Click to expand...

There's separation between the femur and tibia on the medial side in order for the lateral meniscus to be "crushed." One would think the medial meniscus would be damaged in this process. Also, by your logic, the posterior cruciate ligament would be torn as well.
 
Upvote 0 Downvote
Ableton said:
There's separation between the femur and tibia on the medial side in order for the lateral meniscus to be "crushed." One would think the medial meniscus would be damaged in this process. Also, by your logic, the posterior cruciate ligament would be torn as well.
Click to expand...

Correction: may or may not. Nothing regarding my assumption presupposes that the PCL would have to be torn. It may seem slightly more likely, but certainly doesn't poke holes in my logic.

And that's the beauty of my logic on this one. All that matters is that it makes sense to me in the context of the correct answer.
 
Upvote 0 Downvote
I saw this in FA 2010 and asked an orthopaedic surgeon about it. According to her, the lateral meniscus is often injured with an ACUTE ACL tear, but chronic ACL tears damage the medial meniscus.
 
Upvote 0 Downvote
Ariodant said:
I saw this in FA 2010 and asked an orthopaedic surgeon about it. According to her, the lateral meniscus is often injured with an ACUTE ACL tear, but chronic ACL tears damage the medial meniscus.
Click to expand...


that is exactly what our anatomy prof said. he advised me to follow that concept if i see a question on the boards.
 
Upvote 0 Downvote
Tikrit01, did you even bother to read the thread before adding in your erroneous information? You are wrong.
 
Upvote 0 Downvote
USMLErx picks Medial meniscus as the correct answer although they post the part of the FA where they list the unhappy triad as being MCL, ACL and Lateral meniscus.. go figure..
 
Upvote 0 Downvote
You must log in or register to reply here.

Similar threads

W
  • Question Question
Radial nerve injury
Replies
6
Views
1K
Wanderer HitchHiker
W
Oh_Gee
  • Question Question
cane use in knee osteoarthritis
Replies
0
Views
489
Oh_Gee
Oh_Gee
R
  • Question Question
USMLE Difference between Beck's triad JVD and Kussmaul sign
Replies
1
Views
4K
WanderingGuitarist
W
MudPhud20XX
  • Question Question
common knee injuries (unhappy triad)
Replies
9
Views
3K
acciddropping
A
E
  • Question Question
DD b/n knee OA & knee RA radiographycally?
Replies
1
Views
937
Ischemia1032
Ischemia1032
Top