Human Anatomy Chapter 9: Joints

Circumduction

("moving in a circle") is moving a limb or finger so that it describes a cone in space. This is a complex movement that combines flexion, abduction, extension, and adduction in succession.

Identify the type of arthritis described in each case: (a) crystallization of uric acid in synovial membranes; (b) erosion of articular cartilage; (c) autoimmune response causing inflammation of the synovial membrane.

(a) Gouty arthritis is caused by crystallization of uric acid in the synovial membranes. (b) Osteoarthritis is the erosion of the articular cartilage. (c) Rheumatoid arthritis is an autoimmune response causing inflammation of the synovial membrane.

Classify each of the joints named in question 6 according to joint shape. For each joint, indicate whether it is uniaxial, biaxial, or multiaxial.

(a) The elbow is a uniaxial hinge joint. (b) The hip is a multiaxial ball-and-socket joint. (c) The ankle is a uniaxial hinge joint. (d) The atlantoaxial joint is a uniaxial pivot joint. (e) The metacarpophalangeal joint is a biaxial condylar joint.

Name all the movements that occur at these joints: (a) elbow, (b) hip, (c) ankle, (d) atlantoaxial joint, (e) metacarpophalangeal joint.

(a) The movements that occur at the elbow are flexion and extension. (b) The hip allows flexion/extension, abduction/adduction, medial and lateral rotation, and circumduction. (c) Dorsiflexion and plantar flexion occur at the ankle. (d) Rotation occurs at the atlantoaxial joint, as in turning your head to indicate "no". (e) The metacarpophalangeal joint can produce flexion/extension, abduction/adduction, and circumduction.

Adduction

("moving toward") is the opposite of abduction: the movement of a limb toward the body midline or, in the case of the digits, toward the midline (longest digit) of the hand or foot.

synovial joints structure: Sensory nerves

Detect pain. Most monitor how much the capsule is being stretched

synovial joints structure: Synovial fluid

A viscous fluid similar to raw egg white. it is A filtrate of blood. Arises from capillaries in synovial membrane. Contains glycoprotein molecules secreted by fibroblasts. Weeping lubrications Pressure on joints squeezes synovial fluid into and out of articular cartilage

fibrous joint: suture

Bones are tightly bound by a minimal amount of fibrous tissue. they are Immobile. Occur only between the bones of the skull. Allow bone growth so the skull can expand with brain during childhood. Fibrous tissue ossifies in middle age. Synostoses—closed sutures

what are the Joints of the Pelvic Girdle and Lower Limbs?

Hip (Coxal) joint, Knee joint, Talocural (Ankle) joint

Of the shoulder, elbow, or wrist, which joint is the most stable? Which is the least stable?

The elbow is the most stable, and the shoulder is the least stable.

synovial joints structure: Articular cartilages

The ends of the opposing bones are covered by articular cartilages composed of hyaline cartilage. These spongy cushions absorb compressive forces placed on the joint and thereby keep the bone ends from being crushed.

function

based on the relative degree of mobility between the 2 bones

structure

based on the type of connective tissue involved in the binding of the 2 bones

Plantar flexion

depressing the foot or elevating the heel (pointing the toes)

Bursitis

inflammation of a bursa due to injury or friction

Lyme disease

inflammatory disease often resulting in joint pain

types of joint injuries

torn cartilage, sprain, dislocation

Inversion

turn medially

Diarthrosis (DA)

a freely mobile joint; common in appendicular skeleton (all synovial joints)

Amphiarthrosis (AA)

a slightly mobile joint; common in axial skeleton (ex: tibia/fibula; intervertebral discs)

Synarthrosis (SA)

an immovable joint; common in axial skeleton (ex: cranial suture; epiphyseal plate)

articulation

another word for a joint. Where a bone makes contact with another bone, cartilage or teeth

Bursae and Tendon Sheaths

are not synovial joints: Closed bags of lubricant that reduce friction between body elements

structure: Cartilaginous

bones held together by cartilage. Lack a joint cavity. Ex: epiphyseal plate, intervertebral discs

structure: Fibrous

bones held together by dense regular connective tissue. Do not have a joint cavity. Most are immovable or slightly movable. Ex: suture joint between cranial bones, tooth in jaw

structure: Synovial

bones separated by a fluid-filled cavity which is enclosed by a capsule and stabilized by ligaments. Most movable type of joint. All are diarthroses. Ex: elbow joint, hip joint

torn cartilage

common injury to meniscus of knee joint

flexion

decreases the angle between the bones, bringing these bones closer together. Examples include flexion of the neck or trunk; flexion of the fingers, as in making a fist; and flexion of the forearm toward the arm at the elbow.

Arthritis

describes over 100 kinds of jointdamaging diseases. Osteoarthritis is the most common type of "wear and tear" arthritis. Rheumatoid arthritis is a chronic inflammatory disorder. Gouty arthritis (gout) is when uric acid buildup causes pain in joints.

tendon sheaths

elongated bursa that wraps around a tendon particularly found in confined areas (wrist and ankle) where many tendons rub up against each other

bursae

fibrous, saclike structure filled with synovial fluid. Found around the outside of most synovial joints. Reduce friction between where ligaments, muscles, tendons and bones rub together

Abduction

from Latin words meaning "moving away," is movement of a limb away from the body midline. Raising the arm or thigh laterally is an example of abduction. For the fingers or toes, abduction means spreading them apart. Note that bending the trunk away from the body midline to the right or left is called lateral flexion instead of abduction

Tendonitis

inflammation of a tendon sheath

fibrous joint: gomphoses

is a peg-in-socket joint. The only example is the articulation of a tooth with its socket. In this case, the connecting ligament is the short periodontal ligament. it is immobile

extensions

is the reverse of flexion and occurs at the same joints. It increases the angle between the joining bones and is a straightening action. Straightening the fingers after making a fist is an example of extension. At the shoulder and the hip, extension moves the limb posteriorly. Bending a joint back beyond its normal range of motion is called hyperextension. Individuals who have loose ligaments that allow a greater range of motion can be capable of hyperextending the joints.

Rotation

is the turning movement of a bone around the longitudinal axis. This motion occurs along the transverse plane. it is the only movement allowed between the first two cervical vertebrae. The entire vertebral column also rotates, twisting the whole trunk to the right or left. Rotation also occurs at the hip and shoulder joints. Rotation of the limbs may be directed toward the median plane or away from it.

Temporomandibular joint

it Is a modified hinge joint. The head of the mandible articulates with the temporal bone. Lateral excursion is a side-to-side movement. Two surfaces of the articular disc allow: Hingelike movement, Gliding of superior surface anteriorly

Sternoclavicular joint

it Is a saddle joint, Four ligaments surround the joint: Anterior and posterior sternoclavicular ligaments, Interclavicular ligament, Costoclavicular ligament. Performs multiple complex movements

elevation

lifting a body part superiorly

sprain

ligaments of a reinforcing joint are stretched or torn

synovial joints function

lubricating devices. Friction could overheat and destroy joint tissue. Are subjected to compressive forces. Fluid is squeezed out as opposing cartilages touch. Cartilages ride on the slippery film

dislocation

occurs when the bones of a joint are forced out of alignment

Pronation

occurs when the radius rotates medially so that the palm faces posteriorly (hand lying "belly" side down, as in a prone float).

what are the types of fibrous joints?

sutures, syndesmoses, and gomphoses.

what are the types of cartilaginous joints?

synchondroses and symphyses.

fibrous joint: syndesmoses

the bones are connected exclusively by ligaments, bands of fibrous tissue longer than those that occur in sutures. The amount of movement allowed depends on the length of the connecting fibers. If the fibers are short, as in the distal tibiofibular articulation, little to no movement is allowed. If the fibers are quite long, as in the interosseous membrane between the radius and ulna, a large amount of movement is possible.

eversion

turn laterally.

Supination

when the forearm, specifically the radius, rotates laterally so that the palm faces anteriorly (the hand is lying on its "back," supine).

retraction

you bring it back the body part after protraction

cartilaginous joint: synchondroses

A joint where hyaline cartilage unites the bones.The epiphyseal plates are synchondroses. Functionally, these plates are classified as immovable synarthroses. Another example is the immovable joint between the first rib's costal cartilage and the manubrium of the sternum

Why is an injured joint more susceptible to repeat of the injury following a sprain or subluxation?

A sprain or subluxation stretches the joint capsule and surrounding ligaments and makes the joint more susceptible to repeat injury.

What types of cartilage are found in a symphysis joint? Name one location of this type of joint.

A symphysis joint contains both hyaline cartilage, which covers the articular joint surfaces, and fibrocartilage, which unites adjoining bones. Symphysis joints are found between the vertebral bodies (intervertebral discs) and joining the pubic bones (pubic symphysis).

Define each of the following terms: synarthrosis, syndesmosis, synchondrosis. Which of these terms is a functional classification of joints?

A synarthrosis is an immovable joint. This is a functional joint classification. A syndesmosis is a fibrous joint where the adjoining bones are connected exclusively by ligaments. A synchondrosis is a cartilaginous joint where hyaline cartilage unites adjoining bones. Both syndesmosis and synchrondrosis are considered structural classifications.

Condylar (or ellipsoid) joints

Allow moving bone to travel. Side to side—abduction-adduction. Back and forth—flexion-extension. Classified as biaxial—movement occurs around two axes

How does an articular disc differ from articular cartilage?

An articular disc is composed of fibrocartilage, and it is located within the joint cavity. Articular cartilage is composed of hyaline cartilage and covers the adjoining surfaces of all synovial joints.

what are the types of structure of the synovial joint?

Articular capsule, Articular cartilages, Synovial fluid, Reinforcing ligaments, Sensory nerves, Have a rich blood supply

Plane joint

Articular surfaces are flat planes. Short gliding movements are allowed. Intertarsal and intercarpal joints. Movements are nonaxial. Gliding does not involve rotation around any axis

Ligaments of the knee joint

Become taut when knee is extended. The extracapsular and capsular ligaments are Fibular and tibial collateral ligament, Oblique popliteal ligament, and Arcuate popliteal ligament

Pivot joints

Classified as uniaxial—rotating bone turns only around its long axis. Ex: Proximal radioulnar joint, Joint between atlas and axis

Knee Joint Intracapsular ligaments

Cruciate ligaments, Cross each other like an "X". Each cruciate ligament runs from the proximal tibia to the distal femur and prevent undesirable movements at the knee. Anterior cruciate ligament—prevents anterior sliding of the tibia. Posterior cruciate ligament—prevents forward sliding of the femur or backward displacement of the tibia

Hinge joints

Cylindrical end of one bone fits into a trough on another bone. Angular movement is allowed in one plane. Ex: Elbow, ankle, and joints between phalanges. Movement is uniaxial—allows movement around one axis only

Radiocarpal (wrist) joint

Diarthrosis, condylar joint between the three proximal carpal bones (scaphoid, lunate and triquetrum) and the distal articular surface of the radius. Composed two smaller joints: Radiocarpal (wrist) joint—joint between the radius and proximal carpals (the scaphoid and lunate). Allows for flexion, extension, adduction, abduction, and circumduction. Intercarpal joint—joint between the proximal and distal rows or carpals. Allows for gliding movement

Shoulder (glenohumeral) joint

Diarthrotic ball-and-socket between head of humerus and glenoid cavity of scapula with glenoid labrum (cartilage covering glenoid cavity). ligaments: coracoacromial, coracohumeral, glenohumeral, transverse humeral. muscles: rotator cuff (4). bursae: subacromial, subcoracoid, subdeltoid, and subscapulars

Knee joint

Diarthrotic hinge between femur, tibia and patella. The largest and most complex joint. Two fibrocartilage menisci occur within the joint cavity. Femoropatellar joint—shares the joint cavity, it Allows patella to glide across the distal femur

Talocural (Ankle) joint

Diathrotic hinge joint between distal ends of tibia and fibula and talus of the tarsals. Allows the movements dorsiflexion and plantar flexion only. Ligaments: deltoid, lateral, anterior and posterior tibiofibular

Elbow joint

Diathrotic hinge joint between humerus, radius and ulna. Allows flexion and extension. Articulation of the humerus with the trochlear notch of the ulna forms the hinge. Tendons of biceps and triceps brachii provide stability. Ligaments: radial (lateral) collateral, ulnar (medial) collateral, anular

Hip (Coxal) joint

Diathrotic, ball-and-socket structure joint between head of femur and acetabulum of os coxae. Movements occur in all axes. it is Limited by ligaments and acetabulum. Stability comes chiefly from acetabulum and capsular ligaments. Muscle tendons contribute somewhat to stability. ligaments: iliofemoral, ischiofemoral, pubofemoral, ligament of head of femur

Saddle joints

Each articular surface has concave and convex surfaces. Classified as biaxial joints. 1st carpometacarpal joint is a good example. Allows opposition of the thumb

Angular Movements

Either increases or decreases the angle between two articulating bones. Examples are: Flexion vs extension, and hyperextension. Abduction vs adduction. Lateral flexion. Circumduction

cartilaginous joint: symphyses

Fibrocartilage unites bones; resists tension and compression. it is a Slightly movable joints that provide strength with flexibility. Hyaline cartilage are present as articular cartilage on the bone

what are the Three types of joints based on structure?

Fibrous, Cartilaginous, Synovial

gliding

Flat surfaces of two bones slip across each other. Gliding occurs between: Carpals, Articular processes of vertebrae, Tarsals

Which ligament is injured in an ankle sprain resulting from forceful inversion?

Forceful inversion of the ankle can sprain the lateral ligament.

what are the Three basic types of movements Allowed by Synovial Joints?

Gliding, Angular movement, Rotation

Dorsiflexion

Lifting the foot so that its superior surface approaches the shin

synovial joints structure: Have a rich blood supply

Most supply the synovial membrane. Provide nourishment to the joint. Extensive capillary beds produce basis of synovial fluid. Branches of several major nerves and blood vessels

Special Movements

Occur only at specific joints and do not readily fit into any category such as: Depression vs. elevation. Protraction vs. retraction. Inversion vs. eversion. Supination vs. Pronation. Dorsiflexion vs. Plantar flexion. Opposition

synovial joints structure: Reinforcing ligaments

Often are thickened parts of the fibrous layer. Connect one bone to another bone. Strengthen and reinforce most synovial membranes

what are the Synovial Joints Classified by Shape?

Plane joint, Hinge joints, Pivot joints, Condylar (or ellipsoid) joints, Saddle joints, Ball-and-socket joints,

Define pronation and supination. At which joints do these movements occur?

Pronation is medial rotation of the forearm such that the palm faces posteriorly; supination is lateral rotation of the forearm such that the palm faces anteriorly. This movement occurs at the proximal and distal radioulnar joints.

Synovial Joints - with articular discs

Some contain an articular disc. Occur in the temporomandibular joint and at the knee joint. Occur in joints whose articulating bones have somewhat different shapes

Ball-and-socket joints

Spherical head of one bone fits into round socket of another. Classified as multiaxial—allow movement in all axes. Shoulder and hip joints are examples

Both the sternoclavicular and temporomandibular joints contain an articular disc. What is the function of this disc in each of these joints?

The articular disc in the sternoclavicular and the temporomandibular joints divide each joint cavity and enable multiple complex movements of each joint.

Name the intracapsular ligaments found in the hip and the knee.

The intracapsular ligament of the hip is the ligament of the head of the femur. The intracapsular ligaments of the knee are the anterior and posterior cruciate ligaments.

synovial joints structure: Articular capsule

The joint cavity is enclosed Double layered capsule. the Outer fibrous layer is formed from dense irregular connective tissue to strengthen the joint. the Inner synovial membrane secretes a viscous, oily fluid that has the following functions: Lubricates the articular cartilages. Provides nourishment to the articular cartilages. Acts as a shock absorber during compression of the joint

Which other joint described in this chapter contains an articular disc?

The knee also contains an articular disc

The articular surfaces of the knee contribute little to the stability of this joint. What additional structural features aid in stabilizing the knee?

The medial and lateral menisci of the knee aid in joint stability, as do the extensive capsular, extracapsular, and intracapsular ligaments. Muscle tone in the quadriceps and hamstring muscles also contribute to stability of the knee.

What structures contribute most to stability of the shoulder joint?

The muscle tendons that cross the shoulder contribute most to its stability.

List the six features common to all synovial joints.

The six features of synovial joints are (1) articular cartilage, (2) a joint cavity, (3) an articular capsule, (4) synovial fluid, (5) reinforcing ligaments, and (6) nerves and vessels.

Which forearm bone forms part of the elbow joint? Which forms part of the wrist joint?

The ulna forms part of the elbow. The radius forms part of the wrist joint.

Opposition

This is the action by which you move your thumb across the palm enabling it to touch the tips of the other fingers on the same hand.

types of Inflammatory and Degenerative Conditions

Bursitis, Tendonitis, Arthritis, Lyme disease

Depression

Moving the elevated part inferiorly

Protraction

Nonangular movements in the anterior and posterior directions

what are the Joints of the Pectoral Girdle and Upper Limbs?

Sternoclavicular joint, Temporomandibular joint, Shoulder (glenohumeral) joint, Elbow joint, Radiocarpal (wrist) joint,

Disorders of Joints

Structure of joints makes them prone to traumatic stress. Function of joints makes them subject to friction and wear. Affected by inflammatory and degenerative processes

Joints can be classified in what two ways?

Structure, Function

what are the Three types of joints based on function?

Synarthrosis (SA), Amphiarthrosis (AA), Diarthrosis (DA)

What are the functions of synovial fluid?

Synovial fluid nourishes the cells of the articular cartilage and lubricates the joint surfaces.

By what age of development are synovial joints formed?

Synovial joints form by week 8 of fetal development.