9.5 - 9.7 Synovial Joint Movements, Anatomy, Disorders, and Development

Comprehensive vocabulary flashcards covering anatomical movements, joint structures, supporting ligaments, clinical disorders, and embryonic joint development.

Flexion

A movement taking place in the sagittal plane that decreases the angle between articulating bones at a joint, or involves anterior bending of the neck or trunk.

Extension

A movement taking place in the sagittal plane that increases the angle between articulating bones at a joint, or involves posterior-directed motion such as straightening from a flexed position.

Lateral Flexion

Bending of the neck or trunk toward the right or left side within the coronal plane.

Hyperextension

An abnormal or excessive extension of a joint beyond its normal range of motion, which can lead to injury.

Abduction

Movement in the coronal plane that moves a limb, hand, finger, or toe laterally away from the midline of the body, or brings the thumb to a $90^\frac{}{}$ perpendicular position pointing out from the palm.

Adduction

Movement in the coronal plane that brings a limb, hand, finger, toe, or thumb toward or across the midline of the body.

Circumduction

Movement of a body region in a circular pattern produced by a sequential combination of flexion, abduction, extension, and adduction at a joint.

Medial Rotation

Rotational movement around the long axis of a bone that brings the anterior surface of a limb toward the midline of the body.

Lateral Rotation

Rotational movement around the long axis of a bone that turns the anterior surface of a limb away from the midline of the body.

Supination

Forearm motion where rotation of the radius returns the radius and ulna to parallel positions and turns the palm to face anteriorly.

Pronation

Forearm motion where rotation of the radius causes it to cross over the ulna to form an X-shape, turning the palm to face posteriorly.

Dorsiflexion

Ankle joint movement that lifts the front of the foot so that the top of the foot moves toward the anterior leg.

Plantar Flexion

Ankle joint movement that lifts the heel of the foot from the ground or points the toes downward.

Inversion

Complex movement involving intertarsal plane joints that turns the bottom or sole of the foot toward the midline of the body.

Eversion

Complex movement involving intertarsal plane joints that turns the bottom or sole of the foot away from the midline of the body.

Protraction

Anterior movement of the scapula or mandible that pushes the shoulder or lower jaw forward.

Retraction

Posterior movement of the scapula or mandible that pulls the lower jaw backward or draws the scapula medially toward the vertebral column.

Elevation

Upward movement of the scapula (such as shrugging the shoulders) or mandible (closing the mouth).

Depression

Downward movement of the scapula or mandible (opening the mouth).

Excursion

Side-to-side movement of the mandible, divided into lateral excursion (moving away from midline) and medial excursion (returning to resting midline position).

Superior Rotation

Movement of the scapula where the glenoid cavity moves upward as the medial end of the scapular spine moves downward, required for full upper limb abduction.

Inferior Rotation

Scapular movement during limb adduction where the glenoid cavity moves downward while the medial end of the scapular spine moves upward.

Opposition

Thumb movement at the first carpometacarpal saddle joint combining flexion and abduction to bring the tip of the thumb into contact with a fingertip of the same hand.

Reposition

Thumb movement returning the thumb from opposition back to its anatomical position next to the index finger.

Zygapophysial Joints

Plane synovial joints (facet joints) formed between the superior and inferior articular processes of adjacent vertebrae.

Atlanto-occipital Joint

Articulation formed between the superior articular processes of the atlas ($\text{C1}$) and the occipital condyles at the base of the skull, permitting forward and backward rocking of the head.

Atlantoaxial Joint

A pivot joint and paired flat articulations between the atlas ($\text{C1}$) and axis ($\text{C2}$) that allow side-to-side rotation of the head.

Temporomandibular Joint

Joint formed by the articulation between the mandibular fossa and articular tubercle of the temporal bone and the condyle of the mandible, containing an internal articular disc.

Glenohumeral Joint

Multiaxial ball-and-socket joint formed between the head of the humerus and the glenoid cavity of the scapula, providing the widest range of motion in the body.

Glenoid Labrum

A lip of fibrocartilage extending around the outer margin of the glenoid cavity that slightly deepens the shoulder socket.

Rotator Cuff

Dynamic structural support formed by the fusion of four muscle tendons (supraspinatus, infraspinatus, teres minor, subscapularis) to the articular capsule walls of the shoulder joint.

Adhesive Capsulitis

A condition also known as frozen shoulder, characterized by scar tissue formation between the articular capsule and surrounding structures following injury.

Elbow Joint

Uniaxial hinge joint consisting of the humeroulnar, humeroradial, and proximal radioulnar articulations enclosed in a single capsule.

Ulnar Collateral Ligament

Triangular intrinsic ligament on the medial side of the elbow spanning from the medial epicondyle of the humerus to the ulna, which resists elbow hyperextension.

Radial Collateral Ligament

Intrinsic ligament on the lateral side of the elbow that arises from the lateral epicondyle of the humerus and blends into the annular ligament.

Annular Ligament

Ring-like ligament encircling the head of the radius to support it at the proximal radioulnar pivot joint during pronation and supination.

Acetabular Labrum

Fibrocartilage lip attached to the outer margin of the acetabulum that deepens the hip joint socket.

Ligament of the Head of the Femur

Intracapsular ligament running between the acetabulum and femoral head that contains an arterial pathway to supply the head of the femur.

Knee Joint

The largest joint of the body, consisting of the femoropatellar joint and the medial and lateral tibiofemoral joints functioning primarily as a hinge.

Tibial Collateral Ligament

Extrinsic medial knee ligament extending from the medial epicondyle of the femur to the tibia, firmly attached on its deep side to the medial meniscus.

Fibular Collateral Ligament

Extrinsic lateral knee ligament extending from the lateral epicondyle of the femur to the head of the fibula.

Anterior Cruciate Ligament

Intracapsular knee ligament that becomes taut in full extension to resist hyperextension and prevent the tibia from sliding too far forward relative to the femur.

Posterior Cruciate Ligament

Strong intracapsular knee ligament supporting the flexed weight-bearing knee to prevent the femur from sliding anteriorly off the top of the tibia.

Terrible Triad Injury

Severe knee injury produced by a powerful blow to the lateral extended knee, sequentially causing tearing of the tibial collateral ligament, damage to the medial meniscus, and rupture of the anterior cruciate ligament.

Talocrural Joint

Uniaxial hinge ankle joint formed by the articulations between the talus bone of the foot and the distal ends of the tibia and fibula.

Subtalar Joint

Plane joint located between the talus and calcaneus bones of the foot that contributes to foot inversion and eversion.

Deltoid Ligament

Broad, strong ligament on the medial side of the ankle supporting the talocrural joint and resisting excessive eversion of the foot.

Inversion Ankle Sprain

Common injury caused by excess foot inversion that damages lateral ankle ligaments, most frequently injuring the anterior talofibular ligament followed by the calcaneofibular ligament.

Pott's Fracture

Severe injury caused by forcible foot eversion where the deltoid ligament shears off the medial malleolus of the tibia, allowing the talus to shift laterally and fracture the distal fibula.

Syndesmotic Ankle Sprain

Ankle injury commonly called a high ankle sprain, caused by lateral twisting of the leg on a planted foot that stretches or tears the distal tibiofibular ligaments.

Mesenchyme

Embryonic connective tissue that serves as the precursor giving rise to all bones, cartilages, and connective tissues of the body.

Intramembranous Ossification

Developmental process where mesenchymal cells differentiate directly into bone-producing cells to form bone tissue, such as at the top and sides of the skull.

Endochondral Ossification

Developmental process where mesenchyme differentiates into a hyaline cartilage model that is gradually replaced over time by bone tissue.

Fontanelles

Broad, connective tissue-filled spaces between developing skull bones in newborns that narrow into suture joints during growth.

Joint Interzone

Region of mesenchyme located between adjacent embryonic cartilage models where synovial joints form, with cell death creating the joint cavity.