Tibial Plateau
The tibial plateau is the proximal tibia’s flattened surface that supports the femoral condyles.
The tibial plateau is the superior, horizontal surface of the proximal tibia that articulates with the femoral condyles to form the primary weight-bearing surfaces of the knee joint. It consists of two distinct concave regions — the medial and lateral articular surfaces — separated by the intercondylar eminence. The plateau plays a vital role in load transmission, joint stability, and movement of the knee. As a major component of the tibiofemoral articulation, it is critical for maintaining proper alignment and shock absorption during gait and standing.
Structure
The tibial plateau comprises two asymmetric articular surfaces — the medial tibial plateau and the lateral tibial plateau — along with the central intercondylar region. The surface is lined with hyaline cartilage and reinforced internally by dense trabecular bone supporting compressive loads from the femur. The overall shape of the plateau is wider anteroposteriorly than mediolaterally and is slightly concave on the medial side and flat or slightly convex laterally.
Medial Tibial Plateau
- Larger in surface area
- More concave than the lateral plateau
- Supports a higher percentage of body weight
Lateral Tibial Plateau
- Smaller surface area
- Flatter or slightly convex
- More susceptible to shear forces due to its geometry
Intercondylar Region
The central non-articular area of the tibial plateau is the intercondylar area, divided into:
- Anterior intercondylar area: Site of attachment for the anterior cruciate ligament (ACL), anterior horns of the menisci
- Intercondylar eminence: Raised bony ridge with medial and lateral intercondylar tubercles, important for cruciate ligament attachment and stabilization
- Posterior intercondylar area: Attachment site for the posterior horns of the menisci and posterior cruciate ligament (PCL)
Location
The tibial plateau is located at the proximal end of the tibia, directly beneath the femoral condyles. It forms the inferior articular surface of the knee joint and lies deep to the quadriceps tendon and patella. It is subcutaneous medially and lies just below the skin surface in thin individuals.
- Superior: Femoral condyles
- Inferior: Tibial metaphysis and shaft
- Anterior: Tibial tuberosity and patellar tendon insertion
- Posterior: Popliteal vessels and posterior capsule of the knee
Function
- Weight-bearing: Transfers loads from the femur to the tibia during standing and movement
- Stability: Works with the menisci and ligaments to stabilize the knee joint during motion
- Articulation: Provides a congruent surface for femoral condyles during flexion, extension, and rotation of the knee
- Shock absorption: Distributes and dissipates compressive and shear forces across the knee joint
Articulations
The tibial plateau forms the lower half of the tibiofemoral joint — the main component of the knee joint.
| Component | Articulating Surface | Joint Type |
|---|---|---|
| Medial compartment | Medial tibial plateau with medial femoral condyle | Synovial hinge (modified) |
| Lateral compartment | Lateral tibial plateau with lateral femoral condyle | Synovial hinge (modified) |
Meniscal Relations
Both the medial and lateral tibial plateaus support the respective menisci — crescent-shaped fibrocartilaginous structures that enhance joint congruency and protect underlying cartilage.
- Medial meniscus: C-shaped, less mobile, attached firmly to the joint capsule and medial collateral ligament
- Lateral meniscus: O-shaped, more mobile, not directly attached to the lateral collateral ligament
Ligament Attachments
Several key ligaments insert into the intercondylar areas of the tibial plateau:
| Ligament | Attachment Site | Function |
|---|---|---|
| Anterior cruciate ligament (ACL) | Anterior intercondylar area | Prevents anterior translation of the tibia |
| Posterior cruciate ligament (PCL) | Posterior intercondylar area | Prevents posterior translation of the tibia |
| Medial meniscus | Anterior and posterior horns attach to medial side of intercondylar region | Load distribution and joint stabilization |
| Lateral meniscus | Anterior and posterior horns attach to lateral side of intercondylar region | Load distribution and joint stabilization |
Blood Supply
The tibial plateau receives its blood supply from the genicular arteries, branches of the popliteal artery:
- Inferior medial genicular artery
- Inferior lateral genicular artery
- Middle genicular artery: Supplies the internal structures including the cruciate ligaments and intercondylar region
The vascularity is rich in the subchondral bone but limited in the central cartilage-bearing areas, which contributes to poor healing potential in certain injuries.
Nerve Supply
The innervation of the tibial plateau and surrounding structures is provided by:
- Tibial nerve: Posterior capsule and deep joint structures
- Femoral nerve: Via branches to the anterior capsule
- Common fibular nerve: Lateral joint capsule
- Obturator nerve: Contributes articular branches to the medial knee
Ossification
The proximal tibial epiphysis, including the plateau, ossifies from a secondary ossification center that appears after birth and fuses with the shaft in late adolescence. The intercondylar eminence develops as part of this ossification process.
- Secondary center appears: Around birth
- Fusion complete: By age 16–18 years
Clinical Significance
- Tibial plateau fractures: Result from high-energy trauma or falls, often involving joint surface depression or split. Require CT for classification and may need surgical repair to restore joint congruity.
- Osteoarthritis: Degeneration of cartilage over the plateau causes joint space narrowing, sclerosis, and pain, especially in the medial compartment.
- Meniscal tears: Damage to the meniscus alters force distribution on the tibial plateau, increasing risk for chondral wear.
- Osteochondral defects: Injuries involving subchondral bone and overlying cartilage, may cause joint locking or instability.
- Bone marrow edema: Seen in MRI as signal changes in subchondral bone; common in overload injuries and early osteoarthritis.
Imaging
Imaging the tibial plateau is essential in diagnosing joint pathology, trauma, or degenerative changes.
- X-ray: AP and lateral knee views help detect joint space changes, fractures, or subchondral sclerosis.
- CT scan: Excellent for detailed evaluation of tibial plateau fractures and surgical planning.
- MRI: Best for assessing cartilage integrity, meniscal attachments, bone marrow changes, and cruciate ligament insertions.
Special views like Schuss view or Rosenberg view can better show early joint space narrowing, particularly in the medial compartment.
