Editing Segond fracture

{{Short description|Avulsion fracture of the lateral tibial condyle of the knee}}
{{Infobox medical condition (new)
| image          = SegondFracture.JPG
| caption        = Segond fracture of left knee
|field= orthopedic
}}
The '''Segond fracture''' is a type of [[avulsion fracture]] ([[soft tissue]] structures pulling off fragments of their [[bone|bony]] attachment) from the [[Tibia|lateral tibial plateau]] of the [[knee]], immediately below the articular surface of the  [[tibia]] (see photo).

==Clinical significance==

Because of the high rate of associated ligamentous and meniscal injury, the presence of a Segond or reverse Segond fracture requires that these other [[pathology|pathologies]] must be specifically ruled out. Or more pragmatically, the orthopaedic team assume that the presence of Segond fracture equals ACL rupture, as the correlation is close to 100%. Increasingly, reconstruction of the ACL is combined with reconstruction of the anterolateral ligament when this associated pathology is present.<ref>{{Cite journal|last1=Fernandes|first1=Levi Reina|last2=Ouanezar|first2=Herve|last3=Saithna|first3=Adnan|last4=Sonnery-Cottet|first4=Bertrand|date=2018-03-20|title=Combined ACL reconstruction and Segond fracture fixation fails to abolish anterolateral rotatory instability|journal=BMJ Case Reports|volume=2018|pages=bcr–2018–224457|doi=10.1136/bcr-2018-224457|issn=1757-790X|pmc=5878234|pmid=29559494}}</ref><ref>{{Cite journal|last1=Saithna|first1=Adnan|last2=Thaunat|first2=Mathieu|last3=Delaloye|first3=Jean Romain|last4=Ouanezar|first4=Hervé|last5=Fayard|first5=Jean Marie|last6=Sonnery-Cottet|first6=Bertrand|date=January 2018|title=Combined ACL and Anterolateral Ligament Reconstruction|journal=JBJS Essential Surgical Techniques|volume=8|issue=1|pages=e2|doi=10.2106/JBJS.ST.17.00045|issn=2160-2204|pmc=6143299|pmid=30233974}}</ref><ref>{{Cite journal|last1=Cavaignac|first1=Etienne|last2=Saithna|first2=Adnan|last3=Monaco|first3=Edoardo|last4=Helito|first4=Camilo P.|last5=Daggett|first5=Matthew|last6=Reina|first6=Nicolas|last7=Sonnery-Cottet|first7=Bertrand|date=April 2018|title=Is Treatment of Segond Fracture Necessary With Combined Anterior Cruciate Ligament Reconstruction? Letter to the Editor|journal=The American Journal of Sports Medicine|volume=46|issue=5|pages=NP13–NP14|doi=10.1177/0363546518764420|pmid=29601246|s2cid=4502322|issn=0363-5465|url=http://irep.ntu.ac.uk/id/eprint/34908/1/12373_Saithna.pdf}}</ref><ref>{{Cite journal|last1=Saithna|first1=Adnan|last2=Cavaignac|first2=Etienne|last3=Monaco|first3=Edoardo|last4=Helito|first4=Camilo Partezani|last5=Ouanezar|first5=Hervé|last6=Daggett|first6=Matt|last7=Sonnery-Cottet|first7=Bertrand|date=April 2018|title=Segond Fractures Are Not a Risk Factor for Anterior Cruciate Ligament Reconstruction Failure: Letter to the Editor|journal=The American Journal of Sports Medicine|volume=46|issue=5|pages=NP23–NP24|doi=10.1177/0363546518765991|pmid=29601244|s2cid=4514223|issn=0363-5465|url=http://irep.ntu.ac.uk/id/eprint/34869/1/12374_Saithna.pdf}}</ref> The long-term benefit of an associated Anterolateral Ligament (ALL) reconstruction at the time of ACL surgery is not known. Attention and research is also being paid to a Lateral extra-articular Tenodesis (LET) instead of ALL.{{cn|date=October 2020}}

==Diagnosis==
Segond and reverse Segond fractures are characterized by a small avulsion,<ref>{{cite journal  |vauthors=Campos JC, Chung CB, Lektrakul N, etal |title=Pathogenesis of the Segond fracture: anatomic and MR imaging evidence of an iliotibial tract or anterior oblique band avulsion |journal=Radiology |volume=219 |issue=2 |pages=381–6 |year=2001 |pmid=11323461 |doi=10.1148/radiology.219.2.r01ma23381}}</ref> or "chip", fragment of characteristic size that is best seen on plain [[radiography]] in the [[Anatomical terms of location|anterior-posterior]] plane.  The avulsed fragment of bone may be very difficult to see on the plain [[x-ray]] exam, and may be better seen on [[computed tomography]]. [[MRI]] may be useful for visualization of the associated [[Trabecular oedema|bone marrow edema]] of the underlying tibial plateau on fat-saturated T2W and STIR images, as well as the associated findings of ligamentous and/or meniscal injury.{{cn|date=October 2020}}

==History==
Originally described by Dr. [[Paul Segond]] in 1879<ref>Segond P. "Recherches cliniques et expérimentales sur les épanchements sanguins du genou par entorse". Progres Med 1879; 7:297–99, 319–21, 340–41.</ref><ref name="Public Domain from Bnf: Recherches cliniques et expérimentales sur les épanchements sanguins du genou par entorse, par Paul Segond,">{{cite book | url=http://gallica.bnf.fr/ark:/12148/bpt6k5712206r | title=Recherches cliniques et expérimentales sur les épanchements sanguins du genou par entorse, par Paul Segond | accessdate=November 6, 2013| year=1879 }}</ref> after a series of [[cadaver]]ic experiments, the Segond fracture occurs in association with tears of the [[anterior cruciate ligament]] (ACL) (75–100%) and injury to the [[medial meniscus]] (66–75%), lateral capsular ligament (now known as the Anterolateral ligament, or ALL), as well as injury to the structures behind the knee.{{cn|date=August 2021}}

A rare, mirror image of the Segond fracture has also been described. The so-called "reverse Segond fracture" can occur after an avulsion fracture of the tibial component of the medial collateral ligament (MCL) in association with posterior cruciate ligament (PCL) and medial meniscal tears.<ref>{{cite journal |vauthors=Escobedo EM, Mills WJ, Hunter JC |title=The "reverse Segond" fracture: association with a tear of the posterior cruciate ligament and medial meniscus |journal=AJR. American Journal of Roentgenology |volume=178 |issue=4 |pages=979–83 |year=2002 |pmid=11906886 |doi=10.2214/ajr.178.4.1780979|s2cid=32377911 }}</ref><ref>Steven Claes, et al.: "Anatomy of the anterolateral ligament of the knee".  Journal of Anatomy, 223: 321–28, Oct 2013</ref>

Segond fracture is typically the result of abnormal varus, or "bowing", stress to the knee, combined with internal rotation of the tibia. Reverse Segond fracture, as its name suggests, is caused by abnormal valgus, or "knock-knee", stress and external rotation.{{cn|date=October 2020}}

Originally thought to be a result of avulsion of the medial third of the lateral collateral ligament, the Segond fracture has been shown by more recent research to relate also to the insertion of the iliotibial tract (ITT) and the anterior oblique band (AOB), a [[ligament]]ous attachment of the [[fibular collateral ligament]] (FCL), to the midportion of the lateral tibia and to be associated with avulsion by the anterolateral ligament (ALL).<ref>Roberts CC, Towers JD, Spangehl MJ et-al. "Advanced MR imaging of the cruciate ligaments". Radiol. Clin. North Am. 2007;45 (6): 1003–16, vi–vii.</ref>

==References==
{{reflist}}

==External links==
{{medical resources
| ICD10          = {{ICD10|S|82|1}}
| AO             = 41-B1
}}
{{Fractures |state=collapsed}}

[[Category:Bone fractures]]