Study of Lower Limb Joints & Joint-Specific Actions Flashcards

35 vocabulary flashcards reviewing the anatomy, joint capsules, ligaments, classifications, and muscle actions of the hip, knee, and ankle joints.

Hip Joint Articulation

The specific articulation formed between the head of the femur and the acetabulum of the hip bone.

Acetabulum

A socket in the hip bone that articulates with the head of the femur and provides a deeper socket than the glenoid cavity of the glenohumeral joint.

Hip Joint Capsule Anterior Attachment

The anterior attachment of the hip joint capsule running from the rim of the acetabulum (labrum) to the intertrochanteric line of the femur.

Intertrochanteric Line

The ridge on the anterior femur between the trochanters where the hip joint capsule attaches, distinguished from the posterior intertrochanteric crest.

Iliofemoral Ligament

A very strong capsule ligament of the hip joint that functions to prevent hyperextension.

Pubofemoral Ligament

A hip joint capsule ligament that prevents hyperabduction ("the splits").

Ischiofemoral Ligament

A posterior capsule ligament of the hip joint that helps prevent hyperextension.

Hip Joint Classification

A ball & socket type joint that permits all ranges of motion.

Primary Source of Hip Abduction

The Gluteus Medius and Gluteus Minimus muscles.

Primary Hip Flexor

The Iliopsoas muscle.

Primary Hip Extensor

The Gluteus Maximus muscle.

Orientation of Hip Flexors and Extensors

Flexors cross anteriorly relative to the hip joint, whereas extensors cross posteriorly.

Femorotibial Articulations

Two of the three femoral articulations comprising the knee joint, located between the femoral condyles and tibial condyles.

Patellofemoral Joint (PFJ)

One of the three articulations of the knee joint, formed between the patella and the anterior surface of the femur.

Weight-Bearing Role of Leg Bones at Knee

The tibia articulates at the knee and bears weight, while the fibula does not articulate at the knee joint.

Primary Source of Knee Joint Stability

The strength of surrounding muscles, especially the Quadriceps femoris muscles.

Secondary Source of Knee Joint Stability

The ligaments connecting the femur to the tibia and fibula.

Medial (Tibial) Collateral Ligament (MCL)

A key knee ligament on the medial side that exists as a direct thickening of the fibrous joint capsule.

Lateral (Fibular) Collateral Ligament (LCL)

A key knee ligament on the lateral side that exists as a thickening of the joint capsule.

Patellar Ligament

A thickening of the knee joint capsule that connects the patella to the tibial tuberosity.

Anterior Cruciate Ligament (ACL)

A key intracapsular knee ligament (not a capsule thickening) that prevents hyperextension and prevents posterior displacement of the femur relative to the tibia.

Posterior Cruciate Ligament (PCL)

A key intracapsular knee ligament that prevents anterior displacement of the femur and acts as a main stabilizer when the knee is flexed and weight-bearing (e.g., walking downhill).

Knee Menisci

Medial and lateral fibrocartilage structures that deepen the tibial condyles and function as shock absorbers in the knee joint.

Medial Meniscus Attachment

A structural feature where the medial meniscus is directly fused with the Medial Collateral Ligament (MCL).

Popliteus Muscle

A muscle that separates the lateral meniscus from the Lateral Collateral Ligament (LCL) and initiates flexion of the knee.

Lateral Meniscus Separation

The structural arrangement in which the lateral meniscus is separated from the Lateral Collateral Ligament (LCL) by the Popliteus muscle.

Knee Joint Classification

A hinge joint that permits flexion and extension.

Knee Extensors

Muscles crossing anteriorly across the knee joint, consisting of all four Quadriceps Femoris muscles.

Knee Flexors

Muscles crossing posteriorly across the knee joint, including all Hamstrings, Gastrocnemius, Sartorius, and Gracilis.

Ankle Joint Articulation

The specific articulation formed between the tibia, fibula, and talus.

Ankle Joint Capsule Structure

A joint capsule that is thin anteriorly and posteriorly, but reinforced medially and laterally by collateral ligaments.

Ankle Joint Classification

A hinge joint that primarily permits dorsiflexion and plantarflexion.

Position of Maximum Ankle Joint Stability

The anatomical state where the ankle joint is stronger and most stable, occurring when dorsiflexed.

Muscles for Ankle Dorsiflexion

Muscles located within the anterior compartment of the leg.

Primary Muscles for Ankle Plantarflexion

The Gastrocnemius and Soleus muscles, along with muscles of the deep posterior leg compartment, assisted by the lateral compartment.