Chapter 8: Joints And Movement

Question: What are the three (3) types of joint movement?

Answer: 1.) Gliding 2.) Angular 3.) Circular

Question: What are the six (6) types of synovial joints?

Answer: 1.) plane (ex: intervertebral) 2.) saddle (ex: carpometacarpal) 3.) hinge (ex: elbow) 4.) pivot (ex: distal radioulnar) 5.) ball-and-socket (ex: hip) 6.) ellipsoid (ex: wrist)

Question: What seven (7) factors determine the range of motion of a given joint?

Answer: 1.) shape of the articular surface of the bones forming the joint 2.) amount and shape of the cartilage covering those articular surfaces 3.) strength and location of ligaments, tendons, and muscles associated with the joint 4.) Bulk of surrounding tissues, such as muscle and adipose tissue 5.) Amount of fluid in and around joint 6.) Amount of pain in and around joint 7.) Amount of use or disuse the joint has received over time

Question: What is the greek root of joint?

Answer: "Arthro"

Define: Tendon Sheaths

Answer: Bursa (pockets filled with synovial fluid) that extend further along than typical and protect tendons.

Define: Diarthroses (joint)

Answer: Freely movable joints (Ex: Synovial)

Define: Synarthroses (joint)

Answer: Immovable joints (Ex: Fibrous joints)

Define: Fontanel

Answer: Similar to Dense Regular Collagenous Connective Tissue, this connective tissue is exclusive to infants are their skull bones are not connected; the fontanel tissue allows the brain and bones flexibility as they grow, stretching to accommodate. There are three types of fontanel tissues: 1.) Sphenoidal (side of head by temple) 2.) Frontal (near front of head) 3.) Occipital (near back of head) (Ex: the 'soft spot' on babies' heads)

Define: Amphiarthroses (joint)

Answer: Slightly movable joints (Ex: Cartilaginous)

Define: Sutural Ligament

Answer: The combination of Dense Regular Collagenous Connective Tissue (in between), periosterum (inner/outer thin membrane covering the bone surface) that form a ligament to strengthen the structure of the skull bones.

Define: Joint Cavity

Answer: The space encapsulating the synovial joint, that is filled with synovial fluid.

Define: Dense Regular Collagenous Connective Tissue

Answer: The tissue between bones of the skull, that fill the "cracks" or in between spaces of the sutures to form a more sound solid structure.

Define: Pivot Joint

Answer: a cylindrical process of a bone that rotates into a ring made up of bone and ligament, making the joint have restricted movement of bones to a singular axis. (Ex: head of radius bone and the proximal end of the ulna bone)

Define: Subluxation

Answer: a partial dislocation of a joint

Define: Circumduction (movement)

Answer: a series of movement involving flexion, extension, abduction, and adduction. (Ex: rotating extended arm in a circular gesture, making a circle in the air; think, a ball pitcher rotating their arm before throwing the baseball to the batter )

Define: Flexion (movement)

Answer: a type of angular movement, where in the bending movement decreases the angle of the joint in order to bring the articulating bones closer (Ex: flexing arm to go up when lifting weights)

Define: Fibrous Joint(s)

the connection between two bones that are held together by two fibrous connective tissue; there is no joint cavity and have little to no movement. There are also three (3) sub-categories to these joints where they are separated by their structure: 1.) sutures 2.) syndesmoses 3.) gomphoses (Ex: Frontal Cranial Bone)

Define: Elevation (movement)

Answer: unique movement to the shoulders, moving a structure superiorly (towards the ceiling, up) (Ex: shrugging shoulders up)

Define: Extension (movement)

Answer: a type of angular movement, where in the straightening movement increases the angle of the joint in order to bring the articulating bones further apart. (Ex: unflexing a knee or elbow)

Define: Meniscus (cartilage)

Answer: a type of articular disk, which is a thin flat pad of fibrocartilage between two ends of bones in a synovial joint, that softens the friction between bones. They exist in the wrist and knee joints.

Define: Multiaxial (movement)

Answer: joints that allow multiple types of movement occurring around several axes.

Define: Fibrous joint

Answer: joints that are united by collagen fibers with no joint cavity

Name the three classifications of joints

1.) Fibrous 2.) Cartilaginous 3.) Synovial

Define: Saddle Joint

Answer: two saddle-shaped articulating surfaces of bones at right angles (90° angles) so that their complimentary surfaces articulate. (Ex: carpometacarpal joint of the thumb)

What two characteristics determine the classification name of a joint?

1.) Joints are named after the major connective tissue type that bind the bones together. 2.) Also, they can be named after the functional category according to their degree of motion.

Define: Elbow Joint

Answer: aka "Cubital joint" ; a compound hinge joint, made of three sub-joints: humeroulnar (humerus and ulna), humeroradial (humerus and radius) and proximal radioulnar (proximal radius and ulnar). The elbow joint does two types of movement: flexion and extension, while also able to do rotation (proximal radioulnar only) pronation/supination. The elbow joint has a joint capsule, made up of the ulnar collateral ligament, radial collateral ligament, radial annular ligament, and olecranon bursa.

Define: Dislocation

Answer: aka "Luxation"; when the articulating surfaces of a joint (where they meet) move out of proper alignment (ex: a shoulder popping out of socket)

Define: Ankle Joint

Answer: aka "Talocrural joint" ; a highly modified hinge joint formed by two articulations of the distal tibia and fibular. The ankle is surrounded by a fibrous capsule, whose ends thicken to form ligaments. The movements performed by the joint are: dorsiflexion, plantar flexion, inversion, and eversion. Ligaments surrounding the ankle joint are: medial, anterior talofibular, calcaneofibular, long plantar, plantar calcaneocuboid, plantar, and calcaneonavicular.

Define: Ellipsoid Joint

Answer: aka "condyloid joint"; a modified ball-and-socket joint, where instead of a circular (ball) shape of the end of the bone, it's shaped in an ellipsoid shape, oval-flat like. (Ex: atlantooccipital joint of the neck)

Define: Hip Joint

Answer: aka "coxal joint" ; joint where the femoral head articulates with the deep concave acetabulum of the hip bone, the latter which is reinforced in stability by the acetabular labrum, and transverse acetabular ligament. It is the most stable ball-and-socket joint, though the mobility is limited compared to the shoulder. The hip joint can perform the following movements: flexion, extension, abduction, adduction, rotation, circumduction. The joint is surrounded by a joint capsule, that is made up of several ligaments including iliofemoral and and ligament of the head of the femur.

Define: Shoulder Joint

Answer: aka "glenohemural joint"; the ball-and-socket joint of the shoulder to the body and is the less stable but more mobile joint in the body. The shoulder joint can perform flexion, extension, abduction, adduction, rotation, and circumduction. Stability is created by four sets of ligaments (glenohumeral, transverse humeral, coracohumeral, and coracoacromial) and four sets of muscles (rotator cuff)

Define: Plane Joint

Answer: aka "gliding joint"; two flat bones whose surfaces glide along side each other and are limited in mobility by ligaments and adjoining bones around them. (Ex: articulate process between vertebrae)

Define: Epiphyseal Plate (bone)

Answer: aka "the growth plate"; the hyaline cartilage that unites an epiphysis (the end part of a long bone) with the shaft of a long bone and is the site where the bone grows longer

Define: Range of Motion

Answer: amount of mobility that can be demonstrated in a given joint

Define: Passive Range of Motion

Answer: an external force makes the join move, making the muscle that normally crosses the given joint, move without activating them (Ex: when a doctor checks the motion of an elbow by holding the limb and making it move)

Define: Periodontal Ligaments

Answer: bundles of connective tissue between gomphoses (joints) and alveoli (teeth sockets)

Define: Lyme Disease

Answer: caused by a bacterial infection that affects multiple organs, including the joints; can lead to chronic arthritis.

Define: Hyperextension (movement)

Answer: extension of a joint beyond the anatomical position. (Ex: rotating the neck to look up, or popping joints)

Define: Sutures

Answer: found only in the bones of the skull, they are the seams where the bones come together in an interlocking texture (touch). There are three (3) sutures in the skull: 1.) coronal 2.) sagittal 3.) lambdoid

Define: Protraction (movement)

Answer: gliding movement that moves a structure in an anterior (front) movement (Ex: jutting out chin, moving the chin forward)

Define: Retraction (movement)

Answer: gliding movement that moves a structure in an posterior (back) movement (Ex: moving the chin (and head) backwards in disgust)

Define: Gout

Answer: group of metabolic disorders that lead to increased production and accumulation of uric acid crystals in tissue, including joint capsules; can lead to arthritis.

Define: Arthritis

Answer: inflammation of a joint, leading to pain and stiffness of the join; over 100 causes in including infectious agents, metabolic disorders, trauma and immune disorders.

Define: Tendinitis

Answer: inflammation of tendon sheaths, often from overuse, such as tennis elbow

Define: Bursitis

Answer: inflammation of the Bursa, enough to cause discomfort, pain, and/or inability to move the joint it protects.

Define: Chondromalacia

Answer: inflammation under the patella and softening of the cartilage; common in young athletes, as well as older active adults

Define: Gliding Movement

Answer: joint movement that occur in plane joints between two flat (or nearly flat) bones that slide or glide over each other, faintly or not touching at all.

Define: Circular Movement

Answer: joint movements that involve rotation around an axis in a circular pattern or an arc.

Define: Angular Movement

Answer: joint movements where the trunk or limb bends relatively to another part of the body. There are two subcategories of angular movements: 1.) Flexion (ex: decrease) 2.) Extension (ex: increase)

Define: Ball-and-socket Joint

Answer: joint where the head (ball) of a bone fits into the socket end of another bone, allowing the joint to be multiaxial and have a large range of movement (Ex: shoulder and hip)

Define: Gomphoses (joint)

Answer: joints consisting of pegs fitting into sockets and are held in place by fine bundles of regular collagenous connective tissue (Ex: joints between teeth and their sockets - alveoli)

Define: Synovial joint

Answer: joints that contain synovial fluid and allow movement the bones and are considered more complex than fibrous and cartilaginous joints. Synovial joints make up the majority of the Appendicular Skeleton's joints. (Ex: knee joint)

Define: Cartilaginous Joint

Answer: joints where two bones are held together by cartilage and exhibit little to no movement. These joints are subdivided by the type of cartilage holding them together: 1.) Synchondoses - hyaline cartilage 2.) Symphyses - fibrocartilage

Define: Synovial membrane

Answer: membrane that is part of the 'joint capsule' that coats the inner surface, facing the joint cavity and the synovial fluid.

Define: Fibrous capsule (membrane)

Answer: membrane that is part of the 'joint capsule' that coats the outside surface, made up of dense irregular connective tissue. This is where ligaments and tendons may touch upon the surface of a joint.

Define: Depression (movement)

Answer: unique movement to the shoulders, moving a structure inferiorly (towards the floor, down) (Ex: releasing shoulders from a shrugging motion, relaxed shoulders after movement)

Define: Knee Joint

Answer: modified hinge joint located between the femur and the tibia, though it is recognized as a complex ellipsoid joint that allows flexion, extension, and some rotation. The joint is stabilized by ligaments and tendons. The four ligaments (anterior cruciate, posterior cruciate, medial collateral and lateral collateral ligament) encapsulate the knee while muscles from the thigh add strength. Multiple bursae surround the knee.

Define: Bunion

Answer: most bunions are deformations of the first metatarsal (the big toe) at the external curve; bursitis may accompany this deformity; irritated by tight shoes

Define: Osteoarthritis

Answer: most common type of arthritis and cause of joint replacement; affects 85% of Americans over the age of 70; "wear and tear" erosion of articular cartilage is the primary problem; characterized by the gradual degeneration of a joint with advancing age; can be delayed with excercise

Define: Abduction (movement)

Answer: movement away from the midline; to take away limbs from the core of the body, like when extending arms during jumping jacks There are two particular subcategories of abduction movements: 1.) ulnar deviation - thumb 2.) radial deviation - wrist (Ex: think abduction - to kidnap)

Define: Plantar Flexion (movement)

Answer: movement of the foot towards the plantar surface (towards the bottom of the foot) (Ex: when standing on tip-toes)

Define: Dorsiflexion (movement)

Answer: movement of the foot towards the shin (upwards) (Ex: when standing on the ball of the heel)

Define: Adduction (movement)

Answer: movement towards the midline; to bring together, like when returning limbs from being extended (Ex: think 'add' - to collect together)

Define: Lateral Excursion (movement)

Answer: moving the mandible (jaw) either left or right from the midline (middle line of the body) , a movement exclusive to the mandible

Define: Arches

Answer: nearly at the bottom of the foot, arches are formed by tarsal and metatarsal bones, where they curve to take on the weight of the body. The ligaments of the arches of the foot perform two purposes: to hold and allow recoiling like flexibility at the movement of the foot to bear weight.

Define: Costochondral Joint

Answer: originally a Synchondroses joint, the joint gradually converts into a synovial joint as movement and expansion of the area between bone and cartilage demands for the area to remain flexible; this is located between the ribs and the sternum

Define: Supination

Answer: rotation of the forearm - specifically - so that the palm faces anteriorly in relation to the anatomical position (Think - "supine" means laying face up) (Ex: palm facing up)

Define: Pronation

Answer: rotation of the forearm - specifically - so that the palm faces posteriorly in relation to the anatomical position. (Think - "prone" means laying down) (Ex: palm facing down)

Define: Rheumatoid Arthritis (RA)

Answer: second most common type of arthritis; chronic progressive inflammation of the joints, resulting in painful deformity and eventually immobility. It most commonly seen in elderly people on their wrists, fingers, feet and ankles.

Define: Articulations

Answer: site where two or more bones meet; bone to bone connection/ joint; bone to cartilage or teeth in bony sockets (aveoli)

Define: Syndesmosis (joint)

Answer: slightly movable type of fibrous joint due to gap of bones and joint, at which the ligaments connecting them allows flexibility (Ex: Radioulnar Syndesmosis - connection of the radius and ulna bones in the forearm)

Define: Joint Capsule

Answer: the encapsulation between bones in a synovial joint, that is made up of fibrous capsule (outer) and synovial membrane (inner). The capsule's inside space is the 'joint cavity'.

Define: Temporomandibular joint (TMJ)

Answer: the joint associated with the mandible condyle and temporal bone, with a fibrocartilage disk fit in between them to soften any friction between the condyle and the fossa of the temporal bone. It is a combination of a PLANE and ELLIPSOID joint, using combined movements and joint characteristics to flex the mandibular open and closed.

Define: Sprain

Answer: the motion of the articular surfaces jarring at the joint due to impact/force, but remaining in alignment, only harming the ligaments that frame the joint (Ex: twisting/spraining ankle versus fracturing ankle)

Define: Ossification

Answer: the process of bone formation, from cartilage or fibrous tissue to bone.

Define: Synostosis

Answer: the process of two or more bones and their sutures forming into one solid bone (Ex: ossification happens with infants to adulthood, but bones never solidify into one solid bone, they are separated by sutures/ joints. Some elderly's suture and bones ossify into one solid unit - though rare.)

Define: Medial Excursion (movement)

Answer: the returning movement of the mandible back to align with the midline after a lateral excursion (moving right or left); the default alignment of the jawline

Question: What dictates the type of a movement of a joint?

Answer: the structure (surface, built, etc.) of a joint dictates what kind of movement they have.

Define: Rotation

Answer: turning of a structure around its long axis. There are two types of rotation: 1.) medial - towards the body (think, palm up, forearm lifted to a 90 degree angle, rotating it towards the body) 2.) lateral - away from the body (think, palm up, forearm lifted to a 90 degree angle, rotating the arm away from the body) (Ex: turning the head to gesture "no")

Define: Eversion (movement)

Answer: turning the ankle so that it faces outward, away from the other foot, away from the midline (Ex: twisting the ankle outwards, the plantar surface facing away from the body)

Define: Inversion (movement)

Answer: turning the ankle so that it faces the opposite foot, plantar surface first, towards the midline (Ex: twisting ankle inward)

Define: Synchondrosis (joint)

Answer: two bones held together by hyaline cartilage that binds bone and cartilage together, allowing little to no movement. Most of these joints are 'temporary' (Ex: epiphyseal plates as bones grow)

Define: Symphysis

Answer: two bones joined by fibrocartilage and are slightly movable because of the flexible nature of the fibrocartilage. (Ex: intervertebral disks)

Question: How does articular cartilage receive nutrients?

Answer: via blood vessels that form a vascular circle at the peripheral margin of the cartilage but do not actually penetrate cartilage or the joint cavity they are a part of. Additional nutrients come from the underlying spongy bone and synovial fluid.

Define: Synovial Fluid

Answer: viscous fluid that fills a (synovial) joint cavity that are made up of polysaccharides, proteins, lipids, secretion of synovial cells, and blood fluid, allowing the slippery consistency to allow flexible joints to move.

Define: Active Range of Motion

Answer: voluntary range of motion by flexing the muscle that normally crosses the given joint

Define: Bursa

Answer: when in joints, the synovial membrane extends from the surface of the bone to create a sort of pocket, away from the joint cavity. Synovial fluid flows into the pocket and it creates a cushion between bones and tendons, for example. (Ex: shoulder and knee joints have bursa pockets)

Define: Hinge Joint

Answer: where a convex cylinder shaped bone fits into a corresponding concavity of another bone. (Ex: elbow and knee joints)

Joints

Areas where two or more bones join together

Define: Uniaxial (movement)

Define: joints that allow only one type of movement, occurring around one axis

Define: Biaxial (movement)

Define: joints that allow two types of movement, occurring around two axes, situated at right angles next to each other

Define: Articular Cartilage

Define: the thin layer of cartilage that covers the ends of bones in a synovial joint, to reduce friction burn between flexing bones, sometimes aided by an 'articular disk' to add more cushion between either bone surfaces.