Anatomy Lecture Chapter 9 and terms

Articulations

A joint, or articulation, is the place of contact between bones, between bone and cartilage, or between bones and teeth. Bones are said to articulate with each other at a joint The study of joints is called arthrology.

Temporomandibular Joint (TMJ)

Formed between the head (condyle) of the mandible with the temporal bone (mandibular fossa). Only mobile joint of the skull bones. Formed by: Articular capsule and articular disc (a thick pad of fibrocartilage) Ligaments: Sphenomandibular, stylomandibular, and temporomandibular. Structural: Synovial (hing, plane) joints Functional: Diarthrosis

Homo-, Homeo-

Same

Atlantoaxial Joint

Synovial (pivot) Diarthrosis Anterior arch of atlas and dens of axis. Head rotation

Carpometacarpal

Synovial (saddle) at thumb, Synovial (plane) at other digits. Diarthrosis Thumb: Trapezium (carpal bone) and first metacarpal Other digits: Carpals and metacarpals II-V Abduction, adduction, circumduction, extension, flexion, and opposition at thumb; gliding at other digits.

Hist-, Histo-

Tissue

Arthritis

A group of inflammatory or degenerative diseases of joints that occur in various forms. Gouty Arthritis: Seen in older individuals. Occurs as a result of an increased level of uric acid in the blood, which causes urate crystals to accumulate in the blood, synovial fluid, and synovial membranes. Osteoarthritis: Most common type of arthritis. It is a chronic degenerative joint condition "wear and tear arthritis." Articular cartilage breaks down first. Rheumatoid Arthritis: Seen in younger and middle-aged adults, more prevalent in women. Presents pain and swelling of the joints, muscle weakness, osteoporosis, and assorted problems with both heart and the blood vessels.

Anatomy of Synovial Joints

Basic features: An articular capsule, a joint cavity, synovial fluid, articular cartilage, ligaments, and nerves and blood vessels.

Hypo-

Below, under

Hem-, Hemato-

Blood

-ferent

Carry

Pubic Symphysis Joint

Cartilaginous (Symphysis) Amphiarthrosis Two pubic bones Very slight movements; more movement during childbirth.

Sternocostal joint

Cartilaginous (Synchondroses) between sternum and first ribs (Synarthrosis) Synovial (plane) between sternum and ribs 2-7 (Diarthrosis) Sternum and first seven pairs of ribs. No movement between sternum and first ribs; some gliding movement permitted between sternum and ribs 2-7.

Lumbosacral Joint

Cartilaginous Joint (Symphysis) between lumbar body and base of sacrum. (Amphiarthrosis) Synovial (plane) joint between articular facets. (diarthrosis) Body of fifth lumbar vertebra and base of the sacrum. Inferior articular facets of fifth lumbar vertebra and superior articular facets of first sacral vertebra. Extension, flexion, lateral flexion of vertebral column.

Synchondroses

Cartilaginous Joint. Articulation in which bones are joined by hyaline cartilage. Synarthrosis (immobile). Hyaline cartilage of epiphyseal plates in children form joints that bind the epiphyses and the diaphysis of long bones. Once the bone stops growing, then synchondrosis no longer exists. Attachment of the first rib to the sternum by costal cartilage (first sternocostal joint). This is formed by hyaline cartilage. Costochondral joints, joints between each bony rib and its respective costal cartilage.

Symphyses

Cartilaginous Joint. Has a pad of fibrocartilage between the articulating bones. This fibrocartilage resists compression and tension stresses and acts as a resilient shock absorber. Amphiarthrosis (slightly mobile). Ex. Pubic symphysis, intervertebral joints (intervertebral discs).

Hetero-

Different

Gyn-

Female, woman

Syndesmoses

Fibrous Joint. Articulating bones are joined by long strands of dense regular CT. Found between the radius and the ulna, and between the tibia and fibula. The shafts of the two articulating bones are bound side-by-side by a broad ligamentous sheet called an interosseous membrane. It provides a pivot point where the radius and ulna can move against one another. Amphiarthrosis (slightly mobile).

Sutures

Fibrous Joint. Found between certain bones of the skull. Has distinct, interlocking, usually irregular edges that both increase their strength and decrease the number of fractures at these articulations. Permits the skull to grow as the brain increases during childhood. Dense regular CT in the sutures become ossified, fusing the skull bones together (in adulthood), becoming synostoses. Synarthrosis (immobile).

Classification of Joints

Fibrous joint, cartilaginous joint, and synovial joint

Diarthrosis

Freely mobile joint

Synovial Joint

Has a fluid-filled joint cavity that separates the cartilage-covered articulating surfaces of the bones. The articulating surfaces are enclosed within a capsule, and the bones are also joined by various ligaments. Diarthrosis (freely mobile). Plane, hinge, pivot, condylar, saddle, and ball-and-socket.

Synarthrosis

Immobile Joint

Knee Joint

Largest and most complex joint. Patellofemoral Joint: Synovial (Hinge and Plane) Diarthrosis Patella and patellar surface of femur Tibiofemoral Joint: Synovial (hinge) Diarthrosis Condyles of femur and condyles of tibia. Movement: Extension, flexion, lateral rotation of leg in flexed position, slight medial rotation. Ligaments: Patellar, fibular (lateral) collateral, tibial (medial) collateral, anterior and posterior cruciate (ALC and PCL)

Hepato-

Liver

Angular Motion (Circumduction)

Movement of a Synovial Joint. A continuous movement that combines flexion, abduction, extension, and adduction in succession; the distal limb or digit moves in a circle.

Special Movements (Dorsiflexion)

Movement of a Synovial Joint. Ankle joint movement whereby the sole of the foot is brought closer to the anterior surface of the leg.

Special Movement (Plantar Flexion)

Movement of a Synovial Joint. Ankle joint movement whereby the sole of the foot is brought closer to the posterior surface of the leg.

Special Movement (Protraction)

Movement of a Synovial Joint. Anterior movement of the body part from anatomic position.

Angular Motion (Hyperextension)

Movement of a Synovial Joint. Extension movement continues past the anatomic position.

Special Movements (Depression)

Movement of a Synovial Joint. Movement of a body part inferiorly.

Special Movements (Elevation)

Movement of a Synovial Joint. Movement of a body part superiorly.

Angular Motion (Abduction)

Movement of a Synovial Joint. Movement of a bone away from the midline; usually in the coronal plane.

Angular Motion (Adduction)

Movement of a Synovial Joint. Movement of a bone toward the midline; usually in the coronal plane.

Special Movement (Retraction)

Movement of a Synovial Joint. Posterior movement of a body part from anatomic position.

Rotational Motion (Supination)

Movement of a Synovial Joint. Rotation of the forearm whereby the palm is turned anteriorly.

Rotational Motion (Pronation)

Movement of a Synovial Joint. Rotation of the forearm whereby the palm is turned posteriorly.

Special Movement (Opposition)

Movement of a Synovial Joint. Special movement of the thumb across the palm toward the fingers to permit grasping and holding of an object.

Angular Motion (Flexion)

Movement of a Synovial Joint. The angle between articulating bones decreases; usually occurs in the sagittal plane.

Angular Motion (Extension)

Movement of a Synovial Joint. The angle between articulating bones increases; usually occurs in the sigittal plane.

Angular Motion (Lateral Flexion)

Movement of a Synovial Joint. The vertebral column moves in either lateral direction along a coronal plane.

Special Movement (Eversion)

Movement of a Synovial Joint. Twisting motion of the foot that turns the sole laterally or outward.

Special Movement (Inversion)

Movement of a Synovial Joint. Twisting motion of the foot that turns the sole medially or inward.

Gliding Motion

Movement of a Synovial Joint. Two opposing articular surfaces slide past each other in almost any direction; the amount of movement is slight.

Intervertebral Articulations

Occurs between the bodies of the vertebrae (amphiarthrosis), as well as between the superior and inferior articular processes of adjacent vertebrae (diarthrosis). Structural: cartilaginous joint Between bodies of vertebrae: All the vertebral bodies (C2-Sacrum) are separated and cushioned by pads of fibrocartilage called intervertebral discs. Each disc has two componenets: An anulus fribrosus (tough outer layer of fribrocartilage that covers each intervertebral disc, contains collagne fibers) and a nucleus pulposus (inner gelatinous core of the disc of the disc and is composed of water, with some scattered reticular and elastic fibers. ligaments: anterior longitudinal, posterior longitudinal, interspinous, supraspinous, ligamentum nuchae, and ligamentum flavum. Between articular facets: Plane joints that glide. Together: Flexion, extension, lateral flexion and some rotation.

Fibrous Joint

Occurs where bones are held together by dense regular (fibrous) CT. Most are immobile or slightly mobile. No cavity. Three types are: Gomphoses, Sutures, and Syndesmoses.

Cartilaginous Joint

Occurs where bones are joined by cartilage. No joint cavity. Synchondroses and symphyses.

Ex-, Exo-

Outside

Extra-

Outside

Hyper-

Over, above

Biaxial

Pertaining to synovial Joints. If the bone moves in two planes or axes.

Uniaxial

Pertaining to synovial joints. If the bone moves in just one plane or axis.

Multiaxial

Pertaining to synovial joints. If the bone moves in multiple planes or axes.

-genesis, -genic

Produce, origin

Shoulder Dislocation

Refers to a dislocation of the acromioclavicular joint. Dislocation is a joint injury in which articulating bones have separated.

Subluxation

Refers to an incomplete dislocation, in which the contact between the bony joint surfaces is altered, but they are still in partial contact.

-form

Resembling, shape of

Idio-

Self, distinct

Haplo-

Single

Amphiarthrosis

Slightly mobile joint

Gastr-, Gastro-

Stomach

Sprain

Stretching or tearing of ligaments, without fracture or dislocation of the joint.

Glyco-

Sugar, sweet

Tibiofibular Joint

Superior Joint: Synovial (plane) (diarthrosis) Inferior Joint: Fibrous (syndesmosis) (amphiarthrosis) Together: amphiarthrosis Superior Joint: Head of fibula and lateral condyle of tibia. Inferior Joint: Distal end of fibula and fibular notch of tibia. Slight rotation of fibula during dorsiflexion of foot.

Functional Classification of Joints

Synarthrosis, Amphiarthrosis, Diarthrosis

Plane Joint

Synovial Diarthrosis (Planar or gliding joint) Simplest and least mobile of synovial joints. Uniaxial, only side-to-side movement. Surfaces of the articulating bones are flat, or planar. Ex. Intercarpal and intertarsal joints (triquetrum and hamate).

Condylar Joint

Synovial Diarthrosis Biaxial (back and forth, side-to-side) An oval, convex surface on one bone that articulates with a concave articular surface on the second bone. Ex. Metacapophalangeal (MP) joints of fingers 2 through 5. "Knuckles"

Hinge Joint

Synovial Diarthrosis Uniaxial Has convex surface of one articulate bone which fits into a concave depression on the other bone. Like a hinge on a door. Ex. Elbow joint, trochlear notch of the ulna fits directly into the trochlea of the humerus, so the forearm can be moved only anteriorly toward the arm or posteriorly away from the arm. In the knee and the finger (interphalangeal [IP]) joints.

Pivot Joint

Synovial Diarthrosis Uniaxial One articulating bone with a rounded surface fits into a ring formed by a ligament and another bone. First bone rotates on its longitudinal axis relative to the second bone. Ex. Proximal radioulnar joint, where the rounded head of the radius pivots along the ulna and permits the radius to rotate. Atlantoaxial joint between the first two cervical vertebrae. The rounded dens of axis fits snugly against an articular facet on the anterior arch of the atlas.

Saddle Joint

Synovial Diarthrosis Biaxial The articular surfaces of the bones have convex and concave regions that resemble the shape of a saddle. Allows for greater range of movement than either a condylar or hinge joint. Ex. Carpometacarpal joint of the thumb (between the trapezium and the first metacarpal). Permits the thumb to move toward the other fingers so that we can grasp objects.

Sternoclavicular Joint

Synovial (Saddle) Joint Sternal end of clavicle, manubrium of sternum, and first costal cartilage. Function: Diarthrosis Movement: Elevates, depression, and circumduction. Has: Articular disc Ligaments: Anterior sternoclavicular, posterior sternoclavicular, costoclavicular, and interclavicular.

Hip (Coxal) Joint

Synovial (ball-and-socket) Joint Diarthrosis Movement: Abduction, adduction, circumduction, extension, flexion, medial and lateral rotation of thigh. Head of femur and acetabulum of os coxae. Has: acetabular labum, articular capsule with retinacular fibers. Ligaments: Iliofemoral, ischiofemoral, pubofemoral. Ligament of the head of the femur.

Glenohumeral (Shoulder) Joint

Synovial (ball-and-socket) joint Glenoid cavity of scapula and head of humerus. Function: Diarthrosis Movement: Abduction, adduction, circumduction, extension, flexion, hyperextension, lateral rotation, and medial rotation. Has: Fibrocartilaginous glenoid labrum encircles and covers the surface of the glenoid cavity. Ligaments: coracoacrimial, coracohumeral, glenohumeral, transverse humeral, and the tendon of the long head of biceps brachii. Muscles: Rotator Cuff (4) Bursae: Subacromial, subcoracoid, subdeltoid, and subscapular.

Atlanto-occipital Joint

Synovial (condylar) Diarthrosis Superior articular facets of atlas and occipital condyles of occipital bone. Extension and flexion of the head; slight lateral flexion of head to sides.

Metatarsophalangeal (MP joints)

Synovial (condylar) Diarthrosis Heads of metatarsals and bases of proximal phalanges. Abduction, adduction, circumduction, extension, and flexion of proxomal phalanges.

Metacarpophalangeal (MP joints "knuckles")

Synovial (condylar) Diarthrosis Head of metacarpals and bases of proximal phalanges. Abduction, adduction, circumduction, extension, and flexion of phalanges.

Radiocarpal (Wrist) Joint

Synovial (condylar) joint Diarthrosis Movement: Abduction, adduction, circumduction, extension, and flexion of wrist. Distal end of radius; lunate, scaphoid, and triquetrum. Has: articular disc

Talocrural Joint

Synovial (hinge) Diarthrosis Distal end of tibia and medial malleolus with talus. Lateral malleolus of fibulaand talus. Movement: Dorsiflexion and plantar flexion. Ligaments: deltoid, lateral, posterior and anterior tibiofibular.

Interphalangeal (IP joints)

Synovial (hinge) Diarthrosis Heads of proximal and middle phalanges with bases of middle and distal phalanges, respectively. Extension and flexion of phalanges.

Interphalangeal (IP Joints)

Synovial (hinge) Diarthrosis Heads of proximal and middle phalanges with bases of middle and distal phalanges, respectively. Extension and flexion of phalanges.

Elbow Joint

Synovial (hinge) joint Diarthrosis Movement: Extension and Flexion of the forearm. Humeroulnar: Trochlea of humerous and trochlear notch of ulna. Humeroradial: Capitulum of humerus and head of radius. Has: thick articular capsule. Ligaments: Radial Collateral, Ulnar collateral, and anular ligament that surrounds the nexk of the radius and binds the proximal head of the radius to the ulna. Allowing for rotation of the radial head against the ulna for pronation and supination of the forearm.

Radioulnar joint

Synovial (pivot) Diarthrosis Proximal joint: Head of radius and radial notch of ulna. Distal Joint: DIstal end of ulna and ulnar notch of radius. Rotation of radius with respect to the ulna.

Intercarpal joint

Synovial (plane) Diarthrosis Adjacent bones in proximal row of carpal bones. Adjacent bones in distal row of carpal bones. Adjacent bones between proximal and distal rows (midcarpal joints). Gliding

Sacroiliac Joint

Synovial (plane) Diarthrosis Articular surfaces of sacrum and ilia Slight gliding; more movement during pregnancy and childbirth.

Intertarsal Joint

Synovial (plane) Diarthrosis Between the tarsal bones Eversion and inversion of foot.

Vertebralcostal Joint

Synovial (plane) Diarthrosis Facets of heads of ribs and bodies of adjacent thoracic vertebrae and intervertebral discs between adjacent vertebrae. Articular part of tubercles of ribs and facets of transverse processes of thoracic vertebrae. Some slight gliding.

Tarsometatarsal Joint

Synovial (plane) Diarthrosis Three cuneiforms (tarsal bones), cuboid, and bases of five metatarsal bones. Slight gliding

Acomioclavicular Joint

Synovial (plane) joint Acromial end of clavicle and acromion of scapula. Function: Diarthrosis Movement: Gliding of scapula on clavicle. Has: articular disc Ligaments: Acromioclavicular and coracoclavicular

Bursa

Synovial Joint. A fibrous, saclike structure that contains synovial fluid and is lined by synovial membrane. Found around most synovial joints and also where bones, ligaments, muscles, skin, or tendons overlie each other and rub together. May be connected to the joint cavity or completely separate from it. Designed to alleviate the friction resulting from various body movements, such as tendon or ligament rubbing against bone. Tendon Sheath: An elongated bursa that wraps around tendons where there may be excessive friction. Common in the confined spaces of the wrist and ankle.

Articular cartilage

Synovial Joint. All articulating bone surfaces in a synovial joint are covered by a thin layer of hyaline cartilage. Reduces friction, acts as a cushion to absorb compression, and prevents damage to the articulating ends of the bones. Lacks perichondrium. Avascular. The repetitious compression / relaxation that occurs during exercise is vital to the articular cartilage's well-being because the accompanying pumping actin enhances its nutrition and waste removal.

Nerves and Blood vessels

Synovial Joint. All have numerous sensory nerves and blood vessels that innnervate and supply the articular capsule and associated ligaments. Sensory nerves detect painful stimuli in the joint and report on the amt of movement and stretch in the joint.

Joint Cavity

Synovial Joint. Also known as articular cavity. A space that contains a small amount of synovial fluid. Permits separation of the articulating bones. Reduces friction as bones move at a synovial joint.

Ligaments

Synovial Joint. Composed of dense regular CT. Connect one bone to another bone and strengthen and reinforce most synovial joints. Extrinsic ligaments: Outside of and physically separate from the articular capsule. Intrinsic ligaments: thickening of the articular cartilage itself. Include extracapsular ligaments outside of the articular capsule and intracapsular ligaments within the articular capsule.

Fat Pads

Synovial Joint. Distributed along the periphery of a synovial joint. Provide some protection for the joint. Fill spaces that form when bones move and the joint cavity changes shape.

Tendons

Synovial Joint. Not part of the joint itself. Composed of dense regular CT. Attaches a muscle to a bone. When a muscle contracts, the tendon from that muscle moves the bone to which it is attached, thus creating movement at the joint. Helps stabilize joints b/c they pass across or around a joint providing mechanical support, and can limit the range or amount of movement permitted at a joint.

Synovial Fluid

Synovial Joint. Synovial membrane secretes a viscous, oily synovial fluid. Composed of secretions from synovial membrane cells and and a filtrate from blood plasma. Three functions: 1) Lubricates the articular cartilage on the articulating bones, 2) Nourishes the articular cartilage's chondrocytes. The small volume of synovial fluid must be circulated continually to provide nutrients and remove wastes to these cells. Whenever movement occurs at a synovial joint, the combined compression and re-expansion of the articular cartilage circulate the synovial fluid into and out of the cartilage matrix. 3) Acts as a shock absorber, distributing stresses and force evenly across the articular surfaces when the pressure in the joint suddenly increases.

Articular Capsule

Synovial joint. Double layered. Fibrous Layer- Outer layer. Dense CT. Strengthens joint to prevent the bones from being pulled apart. Synovial Membrane- Inner layer. Composed mostly of areolar CT, covers all the internal joint surfaces not covered by cartilage, and lines the articular capsule.

"Locking" the Knee

The ability to lock the knees and stand for long periods of time without tiring the leg muscles.

Gloss-, Glosso-

Tongue

Gomphoses

Type of fibrous joint. Articulations of the roots of individual teeth with the sockets of the mandible and the maxillae. A tooth is held firmly in place by a fibrous periodontal membrane. Functionally classified as Synerthrosis (immobile).

Hydro-

Water

Holo-

Whole, entire