Tuesday, April 26, 2011

Knee Injury





This is going to be a tough one. 20 year old female who injured knee playing basketball when she landed from a rebound with knee in hyperextension. Immediate swelling and giving way following injury. When you view this image where is the abnormality located on the radiograph? Where is the injury located on the image? What is the actual diagnosis? This is classic radiology 101! Hint - you will not find this one in your text! Will require some internet searching!
Good luck!

30 comments:

  1. This comment has been removed by the author.

    ReplyDelete
  2. When I view this image, I see an abnormality located on the lateral tibial condyle. It looks as if there is an avulsion fracture of the lateral tibial condyle of the knee, which is known as a Segond fracture. Based upon the subjective observations Rob has given us, it seems that this young lady could have possibly tore her ACL, which pieces together the Segound fracture even better, because these fractures are often associated with tears of the ACL (75-100% of the time) and medial meniscus (66-75% of the time) as well. A lot of time Segound fractures relate to the attachement of the IT band when there is an abnormal varus stress to the knee with internal tibial rotation.

    ReplyDelete
  3. I agree with Ashley's comments. Ashley-Were you a radiologist prior to PT school?! Based on the subjective history of the patient it would make sense the ACL is perhaps involved. I do see an abnormality located on the lateral tibial condyle on this image. After some googling, an avulsion fracture of the lateral tibial condyle a.k.a. Segond fracture seems likely as it is commonly associated with an ACL tear. The Segond fracture is thought to occur at the site of the ITB insertion (Gerdy's tubercle) and perhaps is now thought to involve the anterior oblique band, a ligamentous attachment of the fibular collateral ligament. Further imaging including an MRI is needed after this conventional radiograph to view the ACL and menisci to evaluate possible pathology.

    ReplyDelete
  4. At first I thought you were attempting to trick us by putting up a normal radiograph, but after some scouring of the image I noticed the same lesion that the girls above mentioned. The injury is on the lateral tibial condyle and after googling the Segond fracture mentioned by the girls above I would have to agree that I believe this is what girl is suffering from. Very interesting pathology that I have never head of before.

    ReplyDelete
  5. It definitely helps to click on the picture to enlarge it and then zoom in. By doing this, I was able to actually see there was pathology that existed on the lateral tibial condyle. Before doing this, it looked like a normal radiograph to me. Based on her mechanism of injury, I would first suspect involvement or tear of the ACL; however, this pathology alone would show a normal xray. To see this pathology further testing, such as an MRI would be needed. After researching, I found the same result as the girls have mentioned before. A Segond fracture typically occurs with an ACL tear due to the similar MOI, and this would explain the lesion at the IT band insertion on the radiograph.
    Good one Rob! :)

    ReplyDelete
  6. After searching the internet for AP images of the knee so that I could compare a “normal” image to this one, I agree that the lateral tibial condyle does appear to have an abnormality. Considering that the patient’s history included playing basketball, hyperextending her knee, immediate swelling and giving way it would seem likely that she suffered an ACL injury. I also agree that the Segond fracture is about the likeliest bony injury that would occur with an ACL injury and is apparent on the radiograph. A Segond fracture was originally thought to be a result of avulsion of the medial third of the lateral collateral ligament, but has been shown by more recent research to relate also to the insertion of the ITB and the anterior oblique band which is a ligamentous attachment of the LCL, to the midportion of the lateral tibia. Since there is a high rate of associated ligamentous and meniscal injury, the presence of a Segond fx requires that these other pathologies must be specifically ruled out. CT is better able to demonstrate the Segond fracture than x-ray however is unlikely they would use this as their first diagnostic tool. I would also suggest an MRI due to ACL pathology.

    ReplyDelete
  7. Unfortunately, I don't have much to add from what has already been stated. I could not detect any abnormality, but once enlarged, there was evidence of an avulsion fracture on the lateral tibial condyle, aka a Segond fracture. As mentioned above, it occurs in association with tears of the ACL (75–100%) and injury to the medial meniscus (66–75%), as well as injury to the structures behind the knee. It is a result of abnormal varus stress combined with IR of the tibia. This injury is best seen on the AP plain radiograph, but can be seen better on a CT. An MRI is indicated to rule out, or find associated injuries, to the other ligaments or the meniscus. I would suspect that there would be damage to the ACL, as well as this Segond fracture, based on MOI.

    Unbeknownst to myself, there also exists a reverse Segond fracture, which is an avulsion fracture of the tibial component of the MCL in association with PCL and medial meniscal tears.

    Barb would be thrilled to know I did my research on Wikipedia!

    ReplyDelete
  8. I will agree with many of the others. Even after looking at image and looking up Ashley's diagnosis, I still had a difficult time seeing this one. For future classes, I would recommend that the board certified radiologist (Ashley) has to respond last and not ruin the efforts of everyone else. I was inclined to think ACL based on the patient's sex and MOI. Had Ashley or anyone else not pointed this out, I would have struggled base on the image alone.

    ReplyDelete
  9. This is a Segond fracture, which is an avulsion of the proximal lateral tibia just beneath the articular surface, resulting from excessive varus and IR force at the knee. It is typically associated with ACL tears (in 75-100%). You can see the bone fragment on the lateral aspect of the knee, just superior to the fibular head, in the radiograph above. When a Segond fx is identified on the plain film, MRI is indicated to evaluate the ACL and possible injuries to menisci and other structures.

    ReplyDelete
  10. NOT that this is how I came up with my answer (I started with ACL tear based on MOI and went from there), but just FYI for Rob--if you click on the radiograph above, it opens a new window with the enlarged image, and the title of the window says "Segound Fx"...dead give away :)

    ReplyDelete
  11. What I found from searching Wheeless' Textbook of Orthopaedics website, was that with hyperextension injuries, there is often a small avulsion fracture of the proximal part of the tibia that is seen just proximal to fibular head on the AP radiograph and is nearly always associated w/ torn ACL. On this radiograph you can see an abnormality on the lateral tibia superior to the fibular head, which is likely an avulsion fracture of the lateral tibial plateau. The actual diagnosis would be a torn ACL which makes sense with the s/s being immediate swelling and giving way of the knee.

    ReplyDelete
  12. Honestly if it wasn't for reading the other posts I wouldn't have been able to figure it out. Just because it was given away on the first post, doesn't mean it still wasn't a good education experience. I didn't even know what a Segond fracture was, and now I do. From the original subjective history I would've suspected ACL and possibly found the dx that way. It's an avulsion fx on lateral tibia, dx = Segond Fracture of the R Tibia. Nothing else to say, everyone else stated all the facts.

    ReplyDelete
  13. I would have to agree with Ryan and Cassie (and everyone else) on this one. If I hadn't read everyone's posts, I don't know if I would have been observant enough to catch the avulsion fracture. However, I would have figured it out thanks to Rob for naming the image "Segound+fx.jpg", that sure does help me figure it out!
    Nevertheless, it was a good post because although I did suspect an ACL injury, I did not know that such a thing as a Segound fracture existed. At least, now this is something I can keep in mind when I have any future patients with a possible ACL tear.

    ReplyDelete
  14. Well, I don't have anything better to add! Good eyes Cassie, on finding the Segound fracture in the link..lol. and Ashley always gets them right. Good job! When I looked at the image it looked like the injury was on both the lateral tibial condyle and the left femoral condyle. There is greater space between the lateral femoral and tibial condyles than the medial which suggests the swelling and bleeding in the joint. I did not even know these typy of injuries could occur. I would have just thought it was ACL tear and this is great to know for future reference in patients with this mechanism of injury.

    ReplyDelete
  15. I don’t really have anything new to add to the discussion. When I first looked at the radiograph, I thought that it had to be a normal knee. However, after magnifying the image, I noticed the avulsion fracture as well. With the MOI and Google, I was able to determine that it was in fact a Segond fracture associated with an ACL tear. The small avulsion is noted on the lateral tibial condyle just superior to the fibular head. Based on these findings, an MRI is indicated to determine ACL involvement or the involvement of other intra-articular structures. It was interesting to learn about this pathology as it was not something I am familiar with.

    ReplyDelete
  16. OK - as I have already told others - Rookie mistake on my part. I didnt know that the images name would show when you posted it! Good lesson -
    Now for those who have not posted yet! Each person left give me one other radiologic finding that you might see in someone with a Segond fracture? Explain what the other finding would look like, where you would find it and what does the literature say is the incidence of this other finding you are describing. Cut and paste your reference you found your information from.
    RM

    ReplyDelete
  17. As I was looking for information on injuries associated with Segond fractures and I found this article on medial Segond fractures which, according to this article, are associated with PCL and medial meniscus injuries.

    CASE REPORT
    Medial Segond-type fracture: cortical avulsion off the medial tibial plateau associated with tears of the posterior cruciate ligament and medial meniscus
    F. M. Hall and Mary G. Hochman, http://www.springerlink.com/content/3429rnt20cfukywe/

    The only associated injury I found that hasn’t been discussed so far is an avulsion of the tibial eminence, secondary to ACL injury, which may be identified on plain films. Only one of the nine patients in the study had an avulsion of the tibial eminence. This article also discussed the need for the tunnel view in two of the nine cases of Segond fractures used in this study.

    The Segond fracture of the proximal tibia: a small avulsion that reflects major ligamentous damage
    AB Goldman, H Pavlov, and D Rubenstein, http://www.ajronline.org/cgi/content/abstract/151/6/1163

    ReplyDelete
  18. Here is the article I found:
    Posteromedial Tibial Plateau Injury including Avulsion Fracture of the Semimembranous Tendon Insertion Site: Ancillary Sign of Anterior Cruciate Ligament Tear at MR Imaging
    Karence K. Chan, MD, Donald Resnick, MD, Douglas Goodwin, MD, Leanne L. Seeger, MD
    http://radiology.rsna.org/content/211/3/754.full

    This article stated that they found a segound fracture caused by semimembranosus avulsion. The authors did state that is very rare and unless the fragment is displaced it would be very difficult to see. They stated that the semimembranous central tendon inserts at the infraglenoid tubercle of the posteromedial tibial plateau and this is where the avulsion fractures were found using MR imaging.

    ReplyDelete
  19. Falciglia, F, Mastantuoni, G, Guzzanti, V. Segond Fracture With Anterior Cruciate Ligament Tear In An Adolescent. J Orthopaed Traumatol (2008) 9:167–169

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2656983/pdf/10195_2008_Article_26.pdf

    The article states that the other injuries that can be confused for a Segond’s fracture or with the fracture are with other components of the lateral compartment of the knee. A Segond fracture is a sign of a lateral damage and can be associated with a total ACL disruption in a high percentage of cases (75–100%).

    This article states an ACL rupture with a Segond’s fracture has not been reported/reviewed before in an adolescent population even though these types of injuries are occurring at a higher incidence with the introduction of intense sport activities. Therefore this article focuses on the relationship between a Segond’s fracture and ACL injuries with a case study of a 14 year old girl. X-ray of the right knee revealed the Segond fracture with anterior–posterior and oblique views. Dynamic X-ray were also reviewed due to suspected ligamentous involvement. The patient was under anesthesia during the X-ray and did not show a marked passive anterior drawer of the right tibia compared to the contralateral side; however, Lachman and pivot shift tests were slightly positive. During arthroscopy, other intra-articular injuries were excluded and a total intrasubstance ACL tear at its proximal insertion was observed.

    ReplyDelete
  20. I was able to find this regarding the Segond fracture. I was not aware of this particular fracture and it was interesting reading about this type of fracture and its associated injuries. The information I found is pretty consistent with what has already been posted.
    http://brighamrad.harvard.edu/Cases/bwh/hcache/118/full.html
    Segond fractures may be accompanied by other injuries:
    Tear of the anterior cruciate ligament (75-100%).
    Injuries of the medial and lateral menisci (66-70%).
    Avulsion fracture of the fibular head.
    Avulsion fracture of the Gerdy tubercle.

    The first imaging after injury of the knee is a plain radiograph. When a Segond fracture is identified on the plain film or suspected after clinical examination, MRI is indicated to evaluate the anterior cruciate ligament and possible injuries to menisci and other structures.

    ReplyDelete
  21. I agree with the other posts on the Segond fracture. What I could find was that it is commonly associated with anterior cruciate ligament tears (70%) according to http://www.gentili.net/fracture1.asp?ID=107.

    I also found a study about this: Fracture of the posterior aspect of the lateral tibial plateau: radiographic sign of anterior cruciate ligament tear,Stallenberg B, Gevenois PA, Sintzoff SA Jr, Matos C, Andrianne Y, Struyven J.Radiology. 1993 Jun;187(3):821-5.

    According to what I found if a segond fracture is identified on plain radiographs then ligament damage is quite frequently found and MRI is indicated to evaluate the ligament structures of the knee.

    ReplyDelete
  22. I agree with the majority of the other post indicating that Segond fractures can be accompanied by multiple injuries including ACL tears, injuries to the menisci, avulsion fracture of the fibular head and avulsion fracture of the Gerdy tubercle. During my search to find another associated injury I found this article that describes various types of avulsion fractures of the knee including Segond and reverse Segond fracture, ACL and PCL avulsion fracture, IT band avulsion fracture and semimembranosus tendon avulsion fracture. http://radiographics.rsna.org/content/28/6/1755.full
    In the article it also discusses the radiographic appearance and gives the common soft tissue injuries that the fractures are associated with.

    ReplyDelete
  23. As previously stated a radiological finding for a segond fracture would be an avulsion, or bone parts that have been torn away from the lateral tibial tubercle, and other findings that might be noticeable is a ruptured or torn ACL as this injury usualy goes hand in hand with a segond fracture.
    With this article (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2656983/)
    Other places I found talk about possible Medial menisucus injury and this I can also see as an ACL tear can be accompanied with a MM tear.

    ReplyDelete
  24. I also found on http://radiopaedia.org/articles/segond-fracture that the findings of associated injury seem to be fairly consistent with what others have posted.
    Associated ACL tear has an incidence of 75-100%
    Medial/lateral meniscal tear associated incidence is 66-75%
    Avulsion of fibular attachment of long head of biceps femoris and fibular collateral ligament are rare but do happen.
    Plain radiographs would identify the initial fracture (seen as an avulsion, usually of the tibial tubercle), and MRI is needed to identify the secondary associated issues.

    ReplyDelete
  25. Another common radiographic finding with a Segond fracture is joint effusion. I found it interesting that in some patient's, the fracture was present only with the tunnel view and not on an AP view.

    http://www.ajronline.org/cgi/reprint/151/6/1163.pdf

    ReplyDelete
  26. Campos JC, et al. Pathogenesis of the Segond Fracture: Anatomic and MR Imaging Evidence of an Iliotibial Tract or Anterior Oblique Band Avulsion. Radiology. 2001;219(2):381-386.

    http://radiology.rsna.org/content/219/2/381.full.pdf

    Both a clinical and a cadaveric portion to this study. In the clinical aspect of the study they examined radiographs and MRIs in 17 patients with evidence of an acute Segond fracture. Tears of the ACL and knee effusion were present in 16 patients (94%). Tears of the menisci found in 9 patients (53%). Bone contusions found in 14 patients (82%). Injury to posterolateral corner in 6 patients (35%). Tears of MCL in 6 patients (35%). Posterior fibers of the iliotibial tract attached to avulsed fracture in 13 patients (76%).

    ReplyDelete
  27. As most everyone has said, this subjective information screams ACL injury. Upon looking up associated pathologies I saw mention of "kissing contusions" which are highly associated with ACL tears and are the result of the lateral femoral condyle impacting the posterolateral tibial plateau. This article did not state the incidence of this particular injury with Segond fractures but I did see another study that listed the incidence as 6.3% association with the knee injuries of the study's participants. On conventional radiographs these are difficult to see and are better visualized via MRI.

    http://rad.usuhs.edu/medpix/parent.php3?mode=single&recnum=6935&table=card&srchstr=lung%20contusion&search=lung%20contusion#pic

    ReplyDelete
  28. The article I found referenced the occurrence of ACL tears with a Segond fracture. The association ranged from 75% to 100% based on the article being referenced. One study by Dietz et al. sheds some interesting information on the accuracy of a physical exam vs. surgical findings. In this study 15 of 20 patients with a Segond fracture were diagnosed with an ACL tear. However, only 3/8 were diagnosed by physical exam, while 12/12 surgical patients were found to have an ACL tear. Another study by Irvine et al. found that only 1/8 patients had an ACL tear, but this study consisted of only physical exam and therefore is likely inaccurate.

    The article I used was from JOSPT and is titled
    Segond Fracture: Lateral Capsular Ligament Avulsionhttp://www.jospt.org/issues/articleID.717,type.2/article_detail.asp

    ReplyDelete
  29. This injury and MOI was consistent with ACL. The radiograph demonstrated a Segond fx. The article I used was
    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2656983/pdf/10195_2008_Article_26.pdf

    It stated that before Sferopoulos's research/articles/publications, there wasn't any other literature correlating ACL's with lateral collateral ligament avulsion fx's.

    This article was good to read as it went through and explained why the LCL would avulse rather than tear, and why the LCL would even be involved in an ACL injury. It also goes to state how the developing roles of radiographs have become an important diagnostic tool to confirm ACL and LCL injuries.

    ReplyDelete