Lateral Femoral Condyle

For Medical Students

Structure and Location

The lateral condyle is flatter in the sagittal plane than the medial and broader from side to side. It projects further anteriorly, which is why the lateral trochlear facet stands higher than the medial.

Its outer wall carries the lateral epicondyle, and below and behind that a groove, the popliteal sulcus, in which the popliteus tendon lies. Its inner wall forms the lateral wall of the intercondylar notch.

The articular surface carries a shallow groove across it, the lateral condylar notch, marking the line where the meniscus sits in extension.

Relations

Laterally, outside the capsule: the lateral collateral ligament from the epicondyle, the lateral head of gastrocnemius from above and behind the condyle, and the lateral intermuscular septum along the shaft.

The popliteus tendon lies in its sulcus inside the capsule, passing from its origin forward of the collateral down and back to the muscle belly.

Inside the notch, the medial surface of this condyle carries the femoral attachment of the anterior cruciate ligament.

The common peroneal nerve is not a relation of the condyle itself. It lies further distally and laterally, around the fibular neck.

Function

Because the lateral condyle is flatter in profile, the lateral side of the joint translates further through flexion than the medial. The combination of a travelling lateral side and a pivoting medial side produces rotation of the tibia as the knee bends and straightens.

Its anterior projection gives the patella a lateral wall to work against, which is the main bony restraint to lateral patellar translation.

Clinical Relevance

The lateral epicondyle locates the collateral origin, and the relationship between that origin and the popliteus origin is the key to the posterolateral corner.

The anterior cruciate attaches on the inner wall of this condyle, so the lateral condyle is the bone that the femoral side of a reconstruction is placed in.

MRCS Level

Structure and Location

Name three things on the outer wall. The lateral epicondyle carries the collateral origin. The popliteal sulcus, anterior and distal to it, carries the popliteus origin. The supracondylar area above and behind carries the lateral head of gastrocnemius.

The order of the first two is the point: the collateral origin is proximal and posterior to the popliteus origin, and the two tendons therefore cross as they run distally.

On the articular surface, the shallow transverse groove marks the extension position of the lateral meniscus and is a normal feature rather than a defect.

The inner wall is flat, slightly concave, and faces the medial condyle across the notch. The anterior cruciate attachment sits on its posterior part, close to the articular margin.

Relations

The posterolateral corner structures all take their bearings from this condyle: the collateral ligament, the popliteus and its popliteofibular extension, and the arcuate complex.

The capsule attaches around the articular margin and the popliteus tendon enters the joint through a hiatus in it, so the tendon is intra-articular but extrasynovial along part of its course.

The lateral geniculate vessels run on the capsule at this level, with the superior lateral genicular artery passing above the condyle deep to the iliotibial band.

Blood Supply and Innervation

The lateral condylar epiphysis is supplied by the superior lateral and inferior lateral genicular arteries, with the descending branch of the lateral circumflex femoral contributing above.

The notch surface and the anterior cruciate attachment are supplied by the middle genicular artery, which is the vessel to name for any intra-articular structure here.

Articular innervation is from the common peroneal and tibial nerves posterolaterally and the femoral nerve anteriorly. The recurrent branch of the common peroneal supplies the anterolateral capsule.

Function

The lateral compartment is the less constrained of the two: a flatter femoral surface on a convex tibial surface with a mobile meniscus. It permits translation and it depends more on soft tissue restraint for it.

In extension the anterior projection of the condyle resists lateral patellar translation, and that restraint is lost as the patella leaves the trochlea in flexion. 3.13 and Section 3 own the kinematic account.

Clinical Relevance

The femoral attachment of the anterior cruciate is on this condyle, which makes its inner wall the most studied surface in the knee. 2.7.6 owns the footprint.

The collateral and popliteus origins are the two fixed points for posterolateral corner reconstruction, and their relative positions are what makes the reconstruction anatomical or not.

An impression on the articular surface of the lateral condyle is a recognised finding after a pivoting injury, and distinguishing it from the normal transverse groove matters. The finding belongs to Section 5; the normal groove belongs here.

The superior lateral genicular artery lies deep to the iliotibial band above the condyle and is encountered in lateral approaches.

FRCS Level

Relations

The posterolateral corner is the region where the greatest number of named structures attach in the smallest area, and all of them refer to this condyle. Reconstruction there is a matter of restoring two or three fixed points rather than reproducing every structure.

The popliteus hiatus in the capsule is the route by which the tendon becomes intra-articular, and it is also the route by which a lateral meniscal tear can extend into a region with no meniscal attachment.

Function

Lateral condylar geometry is the reason the lateral compartment can be left more mobile than the medial in a reconstructed or replaced knee without the same penalty.

It is also why lateral restraint is soft tissue dependent. Removing or failing to restore the lateral structures has a larger effect than the equivalent on the medial side, because the bone was never doing the work.

Clinical Relevance

Anterolateral rotational control is a live argument, and the anatomy underneath it is the relationship between the lateral condyle, the capsule, and the iliotibial band's deep fibres. The anatomical description belongs here; whether an added lateral procedure helps is an evidence question owned by Sections 6 and 7.

In a lateral approach, the structures at risk in order of depth are the iliotibial band, the superior lateral genicular artery, the capsule, and then the popliteus tendon. Knowing the order is what makes the exposure deliberate.

The femoral tunnel for anterior cruciate reconstruction is drilled through the inner wall and exits on the outer surface, so the condyle's width and the position of the lateral structures both constrain the trajectory.