Tibial Plateau Fractures Workup

Updated: Jul 05, 2018
  • Author: Srinivasa Vidyadhara, MBBS, DNB, MS(Orth), DNB(Orth), FNB(SpineSurg), MNAMS; Chief Editor: Thomas M DeBerardino, MD  more...
  • Print
Workup

Imaging Studies

For a discussion of the challenges in radiologic diagnosis and evaluation of tibial plateau fractures, see Dennan. [11]

Radiography

Most tibial plateau fractures are easy to identify on standard anteroposterior (AP) and lateral projections of the knee. Lateral views should not be considered adequate if a rotational component obscures the visualization of the femoral condyles as a single unit. Rotational malalignment can lead to missed zones of injury and an inaccurate estimation of the degree of articular depression.

With minimally displaced vertical split fractures, the fracture line often lies in an oblique plane and is therefore not visible on an AP or lateral radiograph. Oblique projections should be added if a nondisplaced tibial plateau fracture is suspected but not seen on the standard projections.

The following subtle radiologic signs may indicate the presence of an underlying plateau fracture:

  • Lipohemarthrosis - The presence of a fat/fluid level in the suprapatellar recess on the horizontal-beam lateral projection of the knee indicates that a fracture has occurred and has allowed fatty marrow to enter the joint
  • Increased trabecular density beneath the lateral plateau on an AP film - The medial tibial condyle normally has greater trabecular density because it bears more body weight
  • Nonalignment of the femoral condyles and tibia on the AP view

An AP projection of the knee, angled 15° caudally (tibial plateau view), can provide a more accurate assessment of the depth of plateau surface depression.

Traction radiographs provide a clearer image of the fracture configuration after anatomic alignment is restored. Areas of bone loss resulting from comminution can be mapped, and the appropriate size and length of the necessary implants can be ascertained.

Corresponding views of the uninjured knee and extremity are necessary for each patient to receive accurate restoration of length and alignment of the leg.

Computed tomography

By acquiring thin axial slices through the knee and reconstructing the image data in the sagittal and coronal planes, computed tomography (CT) provides more detailed information. The information obtained from a CT scan can help determine the best surgical approach based on the fracture planes seen on the computer images. Three-dimensional spiral (helical) CT reconstructions yield a better and more accurate demonstration of the tibial plateau fracture. They present the anatomy in the view the surgeon will see when surgery is performed.

Magnetic resonance imaging

Magnetic resonance imaging (MRI) is acknowledged as a reliable and accurate tool for assessing meniscal, collateral, and cruciate ligamentous injury, [12] as well as for identifying occult fractures of the tibial plateau.

A bone bruise is indicated by epiphyseal and metaphyseal changes in T1- and T2-weighted images. The signals indicate normal articular and cortical bone changes and reflect changes in bone marrow. They are thought to represent edema, hyperemia, hemorrhage, and microfracture. Plateau fractures may be visualized on MRIs, even when plain film radiographs are normal.

A major advantage that MRI has over CT is that MRI does not use ionizing radiation. Disadvantages include the higher cost and greater time needed to complete the study (25 minutes for MRI vs 20 seconds for CT), which means that motion artifact can be a problem.