Cartilage and Arthrology

Vocabulary practice flashcards covering cartilage histology, functional and structural classifications of joints, arthrology mechanics, and related clinical pathologies.

Organ system

A structural level of organization that consists of different organs working closely together.

Chondroblasts

Cartilage precursor cells that actively secrete the components of the extracellular matrix (ECM).

Chondrocytes

Mature cartilage cells embedded within lacunae that function to disperse nutrients throughout the cartilaginous matrix.

Hyaline cartilage

The most abundant type of cartilage in the body; a flexible, gristly, pearly blue mass that cushions, supports, and reinforces tissues such as ribs, long bone ends, the nose, trachea, and the embryonic skeleton.

Elastic cartilage

A flexible, pliant cartilage type enriched with elastin fibers that gives it high stretch and allows it to return to its original shape; found in the outer ear, epiglottis, larynx, and auditory tube.

Fibrocartilage

A stiff, firm cartilage consisting of a firm hyaline matrix with densely organized collagen fibers designed to resist compressive forces; found in intervertebral discs, menisci, and the pubic symphysis.

Appositional growth

Growth mechanism of cartilage in which new cartilage is added to the surface by chondroblasts originating from the inner layer of the perichondrium.

Interstitial growth

Growth mechanism of cartilage in which new cartilage is formed within the existing tissue by chondrocytes that divide and secrete additional matrix.

Interarticular fibrocartilage

Flattened fibrocartilaginous plates free on both surfaces and anchored only at their margins (such as the menisci of the knee, temporomandibular, and acromioclavicular joints).

Connecting fibrocartilage

Fibrocartilage interposed between bony surfaces allowing only slight movement, composed of concentric outer rings of fibrous tissue and an inner cartilaginous center (such as intervertebral discs).

Circumferential fibrocartilage

Fibrocartilage rims that surround the margins of articular cavities (such as the glenoid labrum and acetabular labrum) to protect bony rims and deepen the socket.

Stratiform fibrocartilage

A thin fibrocartilage coating lining osseous grooves (such as the intertubercular sulcus) or imbedded within gliding muscle tendons to reduce friction.

Synovium

Soft tissue lining diarthrodial joints, tendon sheaths, and bursae that secretes synovial fluid to lubricate surfaces and prevent cartilage erosion without attaching directly to the articular ends of bones.

Articulation (Joint)

The junction or meeting place where two or more bones interconnect.

Range of motion (ROM)

The normal extent of mobility permitted during a specific joint movement.

Degrees of freedom

The number of distinct axes along which movement can occur in a joint.

Synarthrosis

An immovable, extremely strong joint where the edges of adjacent bones are tightly bound together or interlocked.

Suture

A fibrous synarthrotic joint found exclusively between the bones of the skull, bound tightly by dense fibrous connective tissue.

Gomphosis

A fibrous synarthrosis that binds the teeth into their bony sockets in the maxillae and mandible via periodontal ligaments.

Synchondrosis

A rigid, cartilaginous synarthrosis connecting two articulating bones, such as the bridge between the first ribs and sternum or the epiphyseal plate in growing long bones.

Synostosis

A totally rigid, immovable joint formed by bony fusion when two separate bones fuse and their boundary disappears (such as the coronal suture or epiphyseal lines).

Amphiarthrosis

A slightly movable joint that is stronger than a diarthrosis, in which articulating bones are connected by collagen fibers or cartilage.

Syndesmosis

A fibrous amphiarthrotic joint in which articulating bones are united by a ligament or interosseous membrane (such as the distal articulation between the tibia and fibula).

Symphysis

A cartilaginous amphiarthrotic joint where the articulating bones are separated by a broad wedge or pad of fibrocartilage (such as the pubic symphysis).

Diarthrosis

A freely movable synovial joint typically situated at the ends of long bones, enclosed within an articular capsule and lubricated by synovial fluid.

Gliding joint

A synovial joint permitting slight nonaxial or multiaxial movement in a single plane across flat or nearly flat surfaces (e.g., acromioclavicular and sacroiliac joints).

Hinge joint

A monaxial synovial joint that permits angular movement within a single plane, such as the elbow, knee, and interphalangeal joints.

Pivot joint

A monaxial synovial joint designed exclusively for rotation around a longitudinal axis, such as the atlas/axis articulation and proximal radioulnar joint.

Ellipsoidal joint

A biaxial synovial joint where an oval articular surface fits into an elliptical depression of an adjoining bone (such as the radiocarpal and metacarpophalangeal joints).

Saddle joint

A biaxial synovial joint featuring articular faces with both concave and convex surfaces, exemplified by the first carpometacarpal joint of the thumb.

Ball-and-socket joint

A triaxial synovial joint allowing rotation, angular movements, and circumduction around multiple axes (such as the shoulder and hip joints).

Flexion

An angular motion in the sagittal plane that decreases the angle between articulating bones or raises a limb anteriorly.

Extension

An angular motion in the sagittal plane that increases the angle between articulating bones or moves a limb posteriorly.

Abduction

Movement of a limb or anatomical structure laterally away from the midline in the frontal plane.

Adduction

Movement of a limb or anatomical structure medially toward the midline in the frontal plane.

Circumduction

A circular movement pattern combining flexion, abduction, extension, and adduction such that the moving limb traces out a cone.

Opposition

A special movement of the hand enabling the thumb to touch the tip of any other digit to produce a pincer grasp.

Bursa

A small, fluid-filled fibrous pocket lined with a synovial membrane that cushions and reduces friction between tendons, ligaments, and bones.

Bursitis

Inflammation of a bursa caused by repetitive friction, overuse, or traumatic injury, commonly seen in the knee or elbow.

Gout

A painful inflammatory joint pathology caused by excessive uric acid build-up that leads to the precipitation and deposition of urate crystals within joints.

Temporomandibular joint (TMJ)

A combined hinge and gliding diarthrotic joint formed between the condyle of the mandible and the mandibular fossa of the temporal bone.

Post-CVA shoulder subluxation

A partial dislocation of the glenohumeral joint resulting from paralyzed rotator cuff muscles losing their dynamic stabilizing tone following a stroke.

Developmental dysplasia of the hip

Subluxation or dislocation of an infant girl's hip joint during birth due to maternal hormones loosening pelvic and joint ligaments.