The Segond fracture is a type of avulsion fracture ( soft tissue structures pulling off fragments of their bony attachment) from the lateral tibial plateau of the

knee In humans and other primates, the knee joins the thigh with the human leg, leg and consists of two joints: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest join ...

, 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 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. 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.

Diagnosis

Segond and reverse Segond fractures are characterized by a small avulsion, or "chip", fragment of characteristic size that is best seen on plain

radiography Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeuti ...

in the anterior-posterior plane. The avulsed fragment of bone may be very difficult to see on the plain

x-ray X-rays (or rarely, ''X-radiation'') are a form of high-energy electromagnetic radiation. In many languages, it is referred to as Röntgen radiation, after the German scientist Wilhelm Conrad Röntgen, who discovered it in 1895 and named it ' ...

exam, and may be better seen on

computed tomography A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...

. MRI may be useful for visualization of the associated

bone marrow Bone marrow is a semi-solid tissue found within the spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It is composed of hematopoieti ...

edema Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels tight, the area ma ...

of the underlying tibial plateau on fat-saturated T2W and STIR images, as well as the associated findings of ligamentous and/or meniscal injury.

History

Originally described by Dr. Paul Segond in 1879 after a series of cadaveric 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. 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. 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. 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 ligamentous 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).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.

References

External links

{{Fractures , state=collapsed Bone fractures