2. Tibial plateau fractures
The Schatzker classification system for tibial plateau fractures is widely
used to assess the initial injury, plan management, and predict
prognosis.
Tibial plateau fractures may occur together with meniscal and
ligamentous injuries to the knee.
MRI plays a major role in diagnosing the associated meniscal and
ligamentous injuries to the knee along with nerve and vessel injuries
which helps in planning the management of the patient and asses the
prognosis.
3. Schatzker
Type
Components Mechanism
Type I Lateral tibial plateau
fracture without depression
Low-energy injury
Type II Lateral tibial plateau fracture
with depression
Type III Compression fracture of the
lateral (IIIA) or central (IIIB)
tibial plateau
Type IV Medial tibial plateau fracture High-energy injury
OR
Low-energy trauma to
osteoporotic bones
Type V Bicondylar tibial plateau
fracture
Type VI Tibial plateau fracture with
diaphyseal discontinuity
4. Type I fracture in a 12-year-old boy.
(a) Plain radiograph shows a cortical break at the medial aspect of the lateral tibial
plateau, a finding suggestive of a nondisplaced fracture. (b) Coronal proton-
density–weighted MR image shows a lateral tibial plateau fracture. (c) Sagittal T2-
weighted MR image shows an indistinct anterior cruciate ligament (ACL) with
increased signal intensity (arrow), a finding compatible with a partial tear.
5. Type IIIA fracture in a 31-year-old woman.
(a, b) Posteroanterior (a) and lateral (b) radiographs show ill-defined increased
opacity at the subarticular lateral tibial plateau and a large joint effusion. These
findings are suggestive of a depressed fracture of the lateral tibial plateau, a
Schatzker type IIIA fracture.
(c) Coronal T2-weighted MR image shows depression of the tibial articular
cartilage; the depression is more extensive than indicated on the radiographs.
6. Type IIIB fracture in an 18-year-old man.
(b) Plain radiograph shows a subtle fracture of the anterior tibial spine.
(c) Coronal proton-density–weighted MR image shows a compression fracture of
the intercondylar eminences and the central aspect of the lateral tibial plateau, a
type IIIB fracture.
(d) Sagittal T2-weighted MR image shows an associated avulsion injury
of the ACL (arrow).
7. Four-part fracture in a 41-year-old woman.
(a) Plain radiograph shows a split fracture of the lateral tibial plateau. Initially, the
fracture was treated conservatively with absence of weight bearing. MR imaging
was performed because of continued pain and swelling and clinical suspicion of a
meniscal or ligamentous injury. (b) Coronal proton-density–weighted MR image
shows an unsuspected nondepressed four-part fracture of the tibial plateau. (c)
Sagittal T2-weighted MR image shows contour irregularity and abnormal
high signal intensity of the medial meniscus (arrow), findings compatible with a tear.
8. Evaluation of MCL integrity in two patients with tibial plateau fractures. (a, b)
Coronal CT (a) and T2-weighted MR (b) images of a 34-year-old patient,
who was struck by a motor vehicle while in a crosswalk, show a type IV
fracture (incompletely seen). The MCL has a smooth contour on the CT
image (arrow in a) and is intact on the MR image (arrow in b).
9. (c, d) Coronal CT (c) and T2-weighted MR (d) images
of a 19-year-old woman, who injured her knee while jumping on a
trampoline, show a type VI fracture (incompletely seen). The MCL
has an irregular contour on the CT image (arrow in c) and is
completely torn on the MR image (arrow in d).
10. Evaluation of PCL integrity. (a, b) Sagittal CT (a) and T2-weighted MR
(b) images of a 34-year-old pt show a type IV tibial plateau fracture
(incompletely seen). The PCL has a smooth contour on the CT image
(arrow in a) and is partially torn on the MR image (arrow in b).
11. Why MRI
Management of type I, II, and III fractures centers on
evaluating and repairing the articular cartilage and ligament
injuries.
The fracture-dislocation mechanism of type IV fractures
increases the likelihood of injury to the peroneal nerve or
popliteal vessels.
In Schatzker type V and VI fractures, the status of the soft
tissues dictates management options.
12. Anterior cruciate ligament avulsion
fracture
Anterior cruciate ligament (ACL)
avulsion fracture or tibial eminence
avulsion fracture is a type of avulsion
fracture of the knee. This typically
involves separation of the tibial
attachment of the ACL to variable
degrees. Separation at the femoral
attachment is rare
14. Posterior cruciate ligament avulsion
fracture
Posterior cruciate ligament (PCL) avulsion fractures are a type of
avulsion fracture of the knee that represent the most common isolated
PCL lesion. This typically involves separation of the posterior tibial
insertion of the PCL to variable degrees.
15. Minimally displaced avulsion fracture of the posterior tibial plateau at the
insertion of the posterior cruciate ligament. Increased signal at the mid
portion of the PCL infers partial tear. The anterior cruciate ligament is intact.
Bone marrow oedema involving the intercondylar eminences and lateral
tibial plateau.
Coronal T1 Sagittal PD fat sat
16. Segond fracture
Segond fracture is an avulsion fracture of the knee that involves the
lateral aspect of the tibial plateau and is very frequently (~75% of
cases) associated with disruption of the anterior cruciate ligament
(ACL) tear.
18. Reverse Segond fracture
Reverse Segond fracture is one of the avulsion fracture of the knee,
which is due to avulsion of the deep fibers of the medial collateral
ligament (also known as the menisciotibial or coronary ligament)
involving the medial proximal tibia adjacent to the articular surface. It
is the opposite of the Segond fracture, which involves the lateral
proximal tibia.
19. 36-year-old woman involved in
pedestrian-versus-automobile
collision. Proton density—
weighted fast spin-echo coronal
MR image of knee shows bony
avulsion (arrowhead) of deep
medial collateral ligament with
cortical defect (small arrow).
Large arrow shows peripheral
tear of medial meniscus.
20. Stress fractures
Stress fractures refer to fractures occurring in bone due to a mismatch
of bone strength and chronic mechanical stress placed upon the bone.
Fractures can either be:
Fatigue fracture: abnormal stresses on normal bone
Insufficiency fracture: normal stresses on abnormal bone
As they are often initally occult on plain radiographs, diagnosis is made
acutely with bone scintigraphy or MRI or after some time with repeat
radiographs.
21. On the left a 42-year old man with pain in his left knee.
The pain had started gradually during a 10-mile running competition.
The initial x-ray was reported as normal, but a T2-weigthed gradient
echo of the knee shows bone marrow edema in the proximal tibia
indicating the presence of a stress fracture.
In retrospect, the sclerotic line on the x-ray also indicates the stress-
fracture.
22. On the left a 25-year old professional soccer player with complaints of
the ankle.
Evident marrow abnormalities on coronal STIR sequence MRI was
seen, but there was doubt about the presence of a fracture line.
At 11 months follow-up a clear fracture line is visualized by CT.
23. Stress Injury
Stress injuries represent a spectrum of osseous abnormalities that occur
in response to chronic repetitive stress applied to healthy bone.
Stress injuries are common in athletes and represent approximately
10% of all injuries seen in sports medicine clinics.
The vast majority of stress injuries involve the tibia, followed in order
of decreasing frequency by the tarsal bones, metatarsals, femur, and
fibula
24. MRI has become the imaging modality of choice at most institutions
for evaluating patients with suspected tibial stress injuries.
MRI is more sensitive than radiography, nuclear medicine
scintigraphy, and CT for detecting early stress injuries.
MRI can also identify injuries to the muscles and tendons of the
lower extremity, which are common in athletes and may present with
similar clinical findings as stress injuries.
Fredericson and associates developed an MRI classification system
for tibial stress injuries on the basis of findings of periosteal edema,
bone marrow edema, and intracortical signal abnormality.
25.
26. 24-year-old female with grade 1 tibial stress injury.
A and B, Axial (A) and corresponding coronal (B)
fat-suppressed T2- weighted fast spin-echo images of
calf show mild periosteal edema (arrows) on
medial cortex of mid tibial diaphysis, with no
associated bone marrow signal abnormality.
27. 21-year-old male with grade 2 tibial stress injury.
A, Axial fat-suppressed T2-weighted image of calf
shows mild periosteal edema (arrow) on medial
cortex and mild bone marrow edema (arrowhead)
within intramedullary canal of mid tibial diaphysis.
B, Corresponding sagittal fat suppressed T2-weighted
image shows bone marrow edema (arrow) within
intramedullary canal of mid tibial diaphysis.
28. A, Axial fat-suppressed T2-weighted image of calf shows moderate periosteal
edema (arrow) on medial and posterior cortex and moderate bone marrow edema
(arrowhead) within intramedullary canal of mid tibial diaphysis.
B and C, Corresponding coronal fat suppressed T2-weighted (B) and T1-weighted
spin-echo (C) images show bone marrow edema (arrowheads) within
intramedullary canal and periosteal edema (arrow, B) on medial cortex of mid
tibial diaphysis.
23-year-old female with grade
3 tibial stress injury.
29. A, Axial fat-suppressed T2-weighted image of calf shows moderate bone marrow
edema (arrowhead) within intramedullary canal and multiple focal areas of
intermediate signal intensity (arrows) within anterior and posterior cortex of
mid tibial diaphysis.
B and C, Corresponding sagittal fat suppressed T2-weighted (B) and T1-weighted
(C) images show bone marrow edema (arrowheads) within intramedullary canal
and periosteal edema (arrow, B) on posterior cortex of mid tibial diaphysis.
14-year-old female with grade 4a
tibial stress injury
30. 17-year-old female with grade 4b tibial stress injury and linear areas of intracortical
signal abnormality.
A, Axial fat-suppressed T2-weighted image of calf shows severe bone marrow edema
(long arrow) within intramedullary canal and linear areas of
intermediate signal intensity (short arrow) within posterior cortex of mid tibial
diaphysis. Also note severe periosteal edema (arrowheads) on medial, posterior, and
lateral cortex of mid tibial diaphysis.
B, Corresponding axial T1-weighted image shows bone marrow edema (arrowhead)
within intramedullary canal and linear areas of intermediate signal intensity (arrow)
within posterior cortex of mid tibial diaphysis.
31. C and D, Corresponding sagittal
fat-suppressed T2-weighted (C)
and T1-weighted (D) images
show bone marrow edema
(arrowheads) within
intramedullary canal and linear
areas of intermediate signal
intensity (arrows) within
posterior tibial cortex of mid
tibial diaphysis.
