Anatomy & Physiology Chapter 8 Objectives
When a person does jumping jacks, which limb movements are necessary?
abduction, adduction
Which type of synovial joints permits the greatest range of motion?
ball-&-socket joint provides the widest range of motion of any joint; permits movements in all planes as well as rotational movement on central axis.
Which structural category of joints allows for the greatest range of motion?
diarthrosis.
Compare dorsiflexion to the plantar flexion.
dorisflexion: upward movement of foot/toes plantar flexion: movement extending the ankle, as in standing on tiptoes
Which movements are possible at hinge joints?
flexion/extension
Describe the nucleus pulposus & annulus fibrosus of an intervertebral disc.
nucleus pulposus: soft, elastic, gelatinous core; gives disc resilience & shock absorption ability anulus fibrosus: tough outer ring of fibrocartilage, collagen fibers attach to adjacent vertebrae
Why would improper circulation of synovial fluid cause degeneration of articular cartilages in the affected joint?
nutrients would not be delivered to meet the tissue's needs and wastes would accumulate, damage and ultimately death of cells in the tissue Synovial fluid lubricates the joint, provides nutrients for the chondrocytes of the articular cartilage, and helps to absorb shocks in the joints.
Snapping your fingers involves what movement of the thumb?
opposition
What common age-related factors contribute to the vertebral fractures in the elderly?
osteopenia: inadequate ossification leading to loss of bone mass, occurs between ages 30-40, more severe in women than men. osteoporosis: bone loss sufficient to affect normal function. -loss of bone mass along with reduced cushioning of intervertebral discs, leads to increasing incidence of vertebral fractures in elderly.
Identify the types of synovial joints.
plane joint, hinge joint, pivot joint, condylar joint, saddle joint ball-&-socket joint
What movements are made possible by the rotation of the head of the radius?
pronation & supination of the hand
What hand movements occur when a person wriggles into tight-fitting gloves?
protraction, supination, & pronation
Compare rheumatism with osteoarthritis.
rheumatism: general term indicatiomg pain & stiffness in the bones/muscles osteoarthritis: (degenerative arthritis/degenerative joint disease) most common form of arthritis..caused by cumulative effects of wear & tear on joints, genetic factors affecting collagen formation
Name the joints in which the sacrum participates.
sacro-illiac joint
Name the type of synovial joint for each of the following: shoulder, elbow, ankle, and thumb.
shoulder: ball-&-socket elbow/ankle: hinge thumb: saddle
Which joint attaches the pectoral girdle & upper limb to the axial skeleton.
sternoclavicular joint
What can a person do to slow the progression of arthritis?
By engaging in regular exercise, doing physical therapy, and taking anti-inflammatory drugs.
List the functional & structural categories of joints.
Functional Classifications: SYNOVIAL: no movement, extremely strong AMPIARTHROSIS: little movement, much stronger than diarthrosis. articulating bones connectted by collagen fibers OR cartilage. DIARTHROSIS: freely movable Structural Classification of joints: Fibrous: Suture: synarthrotic joint connected by dense fibrous connective tissue; located between the bones of skull. Gomphosis: synarthrotic joint binding teeth to bony sockets in maxillae & mandible. Syndesmosis: (band/ligament) ampiarthrotic joint with bones connected by a ligament ex: distal joint between tibia & fibula Cartilaginous: held together by cartilage.. SYNCHONDROSIS: synarthrotic joint formed by a rigid, cartilaginous bridge between two articulating bones..ex: between the ends of the 1st pair of ribs & the sternum. SYMPHYSIS: amphiarthrotic joint where articulating bones separated by a pad of fibrocartilage...ex: joint between the 2 pubic bones. SYNOSTOSIS: synarthrotic, totally rigid, immovable joint, formed when bones fuse...ex: frontal suture & epiphyseal lines. SYNOVIAL: Diarhtrotic: permits wider range of motion than any other joint type; located on the ends of long bones.
Describe the types of motion possible at a synovial joint.
Gliding: linear motion, permits sliding motion in any direction on a relatively flat surface. Angular: movement along two axes in one plane, also involves a change in angle Circumduction: special term describing a complex angular movement. proximal end of bone remains fixed while distal end moves in a path that corresponds to a drawing circle. rotation: movement around the longitudinal axis, bone remains fixed, & shaft rotates.
Which ligaments stabilize the medical & lateral surfaces of the elbow joint.
The ulnar collateral ligament stabilizes the medial surface of the elbow joint, and the radial collateral ligament stabilizes the lateral surface of the elbow joint
Describe the key components of synovial joint, & identify their functions.
1. ARTICULAR CARTILAGE: covers bones at joint. structure resembles hyaline cartilage, but no perichondrium. matrix contains more water, than other cartilages. 2. JOINT CAPSULE: sac enclosing the articular ends of the bones in a joint. reinforced with accessory structues (tendons/ligaments). continuous with teh periosteum of each bone..adds strength & mobility to the joint. 3. SYNOVIAL MEMBRANE: lines the interior of the joint capsule. secretes synovial fluid into the... 4.JOINT CAVITY: fluid lubricates, cushions, prevents abrasion, & supports chondrocytes. total quantity of synovial fluid usually less than 3 mL
Compare a bulging disc with a herniated disc.
A bulging disc is an intervertebral disc disease. It is caused by weakened posterior ligaments. Allowing compression of nucleus pulposus and distortion of anulus fibrosus; tough outer layer of cartilage bulges laterally. In a herniated disc, nucleus pulposus breaks through anulus fibrosus & protrudes into the vertebral canal, compressing spinal nerves.
Which ligament is a severely hyperextended knee more likely to damage: the ACL or the PCL?
ACL
Describe the accessory structures of complex synovial joints and identify their functions.
Accessory structures supporting the knee provides support & additional stability; tendon of the quads limits ROM & provides mechanical support. BURSA: small, thin fluid-pocket filled with synovial fluid & lined by synovial membrane; forming connective tissue outside a joint cavity, reduces friction, and absorbs shock. FAT PADS: localized masses of adipose tissue covered by a layer of synovial membrane. protects articular cartilage, fills spaces as joint cavity changes shape. MENISCUS (articular disc): pad of fibrocartilage between opposing bones in synovial joint. [may subdivide synovial cavity, may channel synovial flow], allows variations in the shapes of the articular surfaces.
What signs & symptoms would you expect in a person who has damaged the menisci of the knee joint?
Decreases the joint's stability, if a person had to stand for a long time the muscles would fatigue and the knee would "give out", and it also would cause pain.
Define range of motion (ROM).
amount of motion allowed, structurally by anatomical organization.
Which division of the skeleton has the greater range of motion?
appendicular skeleton
Describe the relationship between joint strength & mobility.
joints cannot be both strong & hihgly mobile. as a result, the more movable a joint is, the weaker it will be.
Name the primary vertebral ligaments.
ligamentum flavum: connects laminae of adjacent vertebrae posterior longitudinal ligament: connects posterior surfaces of adjacent vertebral bodies. interspinous ligament: connects spinous processes of adjacent vertebrae supraspinous ligament: connects tips of spinous processes from the sacrum to C7; ligamentum nuchae extends from C7 to base of the skull anterior longitudinal ligament: connects anterior surfaces of adjacent vertebral bodies
Which structures provide most of the stability for the shoulder joint?
the glenoid labrum, rotator cuff muscles, and associated tendons and ligaments
At what site are the iliofemoral ligament, pubofemoral ligament, & ischiofemoral ligament.
the hip joint