Clinical Anatomy: The Knee Joint

Comprehensive vocabulary flashcards covering the clinical anatomy, joint structures, ligaments, musculature, innervation, and clinical tests of the knee joint based on lecture notes.

Patella

A sesamoid bone (knee cap) that sits under tendons, anterior to the knee joint; it protects and distributes force across the femoral condyles and allows the quadriceps to work more efficiently.

Tibiofemoral Joint

A modified hinge synovial joint located between the inferior femoral condyles and superior surface of the tibial condyles; it allows flexion, extension, and medial/lateral rotation, and has an incomplete capsule that blends with ligaments and tendons.

Patellofemoral Joint (PFJ)

A synovial plane/gliding joint between the posterior surface of the patella and the patellar/intercondylar groove (sulcus); the patella glides distally during knee flexion and proximally along an S-curve during knee extension.

Articular Cartilage

Cartilage covering the knee joint surfaces designed to absorb shock and reduce friction.

Tibial Tuberosity

A palpable bony landmark on the superior anterior aspect of the tibia where the patellar tendon attaches.

Anterior Cruciate Ligament (ACL)

An intracapsular ligament that attaches distally to the anterior spine of the tibia and proximally to the posterior-medial aspect of the lateral femoral condyle; it prevents excessive anterior tibial glide.

Posterior Cruciate Ligament (PCL)

An intracapsular ligament that attaches distally to the posterior spine of the tibia and proximally to the anterior-lateral aspect of the medial femoral condyle; it prevents excessive posterior tibial glide and prevents the femur from sliding anteriorly on the tibia.

Medial Collateral Ligament (MCL)

An extracapsular ligament attaching proximally to the medial femoral epicondyle and distally to the medial aspect of the proximal tibia; it blends slightly with the medial meniscus and limits excessive valgus movement.

Lateral Collateral Ligament (LCL)

An extracapsular ligament attaching proximally to the lateral femoral condyle and distally to the head of the fibula; it limits excessive varus movement.

Menisci

Medial and lateral fibrocartilaginous structures with raised edges that sit between the femur and tibia to absorb shock, spread out weight, and provide extra stability to the tibiofemoral joint.

Quadriceps Tendon

The tendon that connects the quadriceps muscles to the patella.

Patellar Tendon

The tendon that extends from the patella to attach onto the tibial tuberosity.

Quadriceps Group

The prime mover muscle group for knee extension, consisting of rectus femoris (middle), vastus lateralis (lateral), vastus medialis (medial), and vastus intermedius (deepest).

Hamstring Group

The prime mover muscle group for knee flexion, consisting of biceps femoris (lateral), semimembranosus (medial), and semitendinosus (medial).

Tibial Nerve

A posterior terminal branch of the sciatic nerve that splits before the knee and continues down the back of the leg.

Common Peroneal Nerve

A branch formed from the split of the sciatic nerve that courses around the outside of the knee and continues down the front of the leg.

Popliteal Artery and Vein

Vessels traversing the popliteal fossa that provide the largest blood supply to the leg and foot.

Popliteal Fossa

The posterior surface marking of the knee containing the sciatic nerve branches (tibial and common peroneal) and vascular structures (femoral and popliteal).

Anterior Drawer Test

A special orthopedic test used to assess anterior knee instability and ACL insufficiency, indicated by forward movement of the tibia greater than $5\,\text{mm}$.

Abduction (Valgus) Stress Test

A clinical examination technique performed at $30^\circ$ of knee flexion to assess medial knee instability and MCL integrity.

End Feel: Knee Extension

A hard (bony) limiting sensation felt at the normal terminal range of $0^\circ\,(+5^\circ/-10^\circ)$ extension.

End Feel: Knee Flexion

A soft (tissue) limiting sensation felt at the normal terminal range of $140^\circ$ flexion.