Anatomy and Physiology Chapter 9 Bryant Miles

Vertebral Movements

1) Flexion or bending anteriorly; 2) Extension or bending laterally; 3) Lateral flexion, or bending laterally; 4) Rotation.

Diarthrosis

Also known as a synovial joint. Diarthroses are subdivided according to the nature of movement permited.

Adventitious Bursae

Bursae that develop in abnormal locations, or because of abnormal stresses.

Intervertebral Discs

Cushioned fibrocartilage pads that separate verebrae. These form symphyseal joints.

Anulus Fibrosus

Each intervertebral has a tough outer layer of fibrocartilage called the anulus fibrosus. The collagen fibers of this layer attach the disc to the bodies of adjacent vertebrae.

Arthritis

Encompasses all the rheumatic diseases that affect synovial joints. Arthritis always involves damage to the articular cartilages, but the specific cause can vary.

Continuous Passive Motion

Encourages the repair process of cartilages by improving the circulation of synovial fluid in injured or inactive joints.

Angular Movement

Ex) Flexion, Extension, Abduction, Adduction, and Circumduction.

Plantar Flexion

Extends the ankle joint and elevates the heel, as when you stand on tiptoe.

Hyperextension

Extension past the anatomical position. Ligaments, bony processes, or soft tissues prevent hyperextension of many joints such as the elbow or the knee.

Dorsiflexion

Flexion at the ankle joint and elevation of the sole.

Autoimmune Disease

A condition in which the body attacks its own tissues.

Bone Formation/Recycling

1) Age of the individual; 2) Physical stresses applied to bone; 3) Circulating hormone levels; 4) Rates of calcium and phosphorus absorption and excretion; 5) Genetic or environmental factors.

Factors Responsible for ROM

1) Collagen fibers of the joint capsule and any accessory, extracapular, or intracapsular ligaments; 2) The shapes of the articulating surfaces and menisci, which may prevent movement in specific directions; 3) The presence of other bones, skeletal muscles, or fat pads around the joint; 4) Tension in tendons attached to the articulating joints.

Types of Movement at Synovial Joints

1) Linear Movement (Gliding); 2) Angular Movement; 3) Rotation.

Funtions of Synovial Fluid

1) Lubrication; 2) Nutrient Distribution; and 3) Shock Absorption.

Elbow Joint Strength

1) The bony surfaces of the ulna and humerus interlock; 2) A single, thick articular capsule surrounds bother the humero-ulnar and proximal radio-ulnar joints; 3) Strong ligaments reinforce the articular capsule.

Synovial Fluid

A clear viscous solution the the consistency of heavy molasses. Resembles interstitial fluid, but contains a high concentration of proteoclycans secreted by fibroblasts of the synovial membrane.

Range of Motion (ROM)

A functional scheme based on the amount of movement possible.

Rheumatism

A general term that indicates pain and stiffness affecting the skeletal or muscular systems or both.

Sprain

A ligament is streched to the point at which some of the collagen fibers are torn, but the ligament as a whole survives and the joint is not damaged.

Amphiarthrosis

A slightly movable joint. This type of joint is either fibrous or carilaginous depending on the nature of the connection between the two. Freely movable joints.

Nucleus Pulposus

A soft, elastic, gelatinous core. Gives the disc resiliency and enables it to absorb shocks. Surrounded by the anulus fibrosus.

Circumduction

A special term for the arm joint in which a circular motion is performed. Ex) Drawing a large circle on the chalk board.

Hip Joint

A sturdy ball and socket diarthrosis that permits flexion, extension, adduction, abduction, circumduction and rotation.

Inversion

A twisting movement of the foot that turns the sole inward elevating the medial edge of the sole.

Eversion

A twisting movement of the foot that turns the sole outward.

Gouty Arthritis

Also known as Crystal Arthritis. Crystals of uric acid form within the synovial joints. The accumulation of crystals or uric acid over time eventually interferes with normal movement.

Condylar Joints

Also known as Ellipsoid Joint. An oval articular faces nestles within a depression in the opposing surface. With such an arrangement, all angular movements occur around two axes, allowing for flexion and extension and abduction and adduction.

Lateral Rotation

Also known as External Rotation or Outward Rotation. The anterior surface of a limb turns away from the long axis of the trunk.

Medial Rotation

Also known as Internal Rotation or Inward Rotation. The anterior surface of a limb turns toward the long axis of the trunk.

Gliding Joints

Also known as Plane Joints. These have flattened or slightly curved faces. The relatively flat articular surfaces slide across one another, but the amount of movement is very slight.

Saddle Joints

Also known as Sellaris Joints. The yfit together like a rider in a saddle. Each articular face is concave along one axis and convex along the other. This arrangement permits angular movement, including circumduction, but prevents rotation.

Joint Capsule

Also known as a articular capsule. A two-layered. Contains an inner synovial membrane and an outer fibrous capsule. This membrane does not cover the articulating surfaces within the joint. Made up of areolar tissue covered by an incomplete epithelial layer. The synovial fluid that fills the cavity originates in the areolar tissue of the synovial membrane.

Meniscus

Also known as articular discs. A pad of fibrocartilage located between opposing bones within a synovial joint. They may subdivide a synovial cavity, channel the flow of synovial fluid, or allow for variation in the shapes of the articular surfaces.

Intrinsic Ligaments

Also known as capsular ligaments. Localized thickenings of the joint capsule.

Articulations

Also known as joints. The only location of movement in the body.

Dislocation

Also known as luxation. When reinforcing structures cannot protect a joint from extreme stresses. The articulating surfaces are forced out of position.

Shoulder Joint

Also known as the glenohumeral joint. Permits the greatest ROM of any joint. Ball and socket diarthrosis.

Monaxial

An articulation that permits movement along only one axes.

Linear Movement

An example of linear movement. The motion can be described by using two lines of reference (axes). Ex) Left-Right, Forward-Backwards, or Diagonally.

Synarthrosis

An immovable joint. Can be fibrous or carilaginous, depending on the connection. Over time the two bones may fuse.

Rheumatoid Arthritis

An inflammatory condition.

Extrinsic Ligaments

Are separate from the joint capsule. These ligamenets may be located either inside or outside the joint capsule, and are called intracapsular or extracapsular ligaments respectively.

Intervertebral Articulations

Articulations between the superior and inferior articular processes of adjacent vertebrae. Gliding joints that permit small movements associated with flexion and rotation of the vertebral column.

Rotation

At the arm you can rotate the joint, but never a complete 360. Separated into Internal Rotation and Lateral Rotation. Limb rotation may be described by reference to the longitudinal axis of the trunk.

Osteoarthritis

Generally affects people 60 or older. Can result from cumulative wear and tear at the joint surfaces or from genetic factors affecting collagen formation.

Abduction

Is movement away from the longitudinal axis of the body in the frontal plane. Ab- (from).

Adduction

Is movement back to anatomical position. Ad- (to). Ex) Wrist movement that brings the heel of the hand toward the body.

Nonaxial

Joints that permit only small sliding movements.

Fat Pads

Localized masses of adipose tissue covered by a layer of synovial membrane. Commonly superficial to the joint capsule. Protect the articular cartilages and act as a packing material for the joint.

Accessory Structures

Meniscus, Fat Pads, Ligaments, Tendons, Bursae

Pivot Joints

Monaxial Joints. They permit only rotation.

Triaxial

Most mobile joints are triaxial. A combination of angular movement and rotation.

Flexion

Movement in the anterior-posterior plane that decreases the angle between the articulating bones.

Biaxial

Movement that can occur along two axes.

Protraction

Moving a body part anteriorly in the horizontal plane. Ex) Sliding the mandible forward. Creates an underbite.

Retraction

Moving a body part posteriorly in the horizontal plane. Ex) Returning the mandible to its normal position.

Extension

Occurs in the anterior-posterior plane and increases the angle between articulating bones. When a person is in the anatomical position, all of the major joints of the axial and appendicular skeletons (except the ankle) are at full extension.

Lateral Flexion

Occurs when your vertebral column bends to the side Most pronounced in the cervical and thoracic regions.

Nursemaids Elbow

Partial dislocation caused by exerting an upward, twisting pull on the elbow.

Subluxation

Partial dislocation.

Hinge Joints

Permit angular movement in a single plane, like the opening and closing of a door.

Rotator Cuff

Primary mechanism for supporting the shoulder joint and limiting its ROM.

Shoulder Separation

Relatively common injury involving partial or complete dislocation of the acromioclavicular joint.

Articular Cartilage

Resemble hyaline cartilages elsewhere in the body. Articular cartilages have no perichondrium (a fibrous sheath) and the matrix contains more H2O than that of other cartilages. The surface is slick and smooth reducing friction during movement at the joint.

Multiaxial

Sliding may occur in any direction.

Bursae

Small, fluid filled pockets in connective tissue. They contain synovial fluid and are lined by a synovial membrane. Bursae may be connected to the joint cavity or separate from it. They form where friction occurs to reduce friction and absorb shock.

Accessory Ligaments

Support, strengthen, and reinforce synovial joints.

Tendons

Tendons pass across or around a joint may limit the joint's ROM and provide mechanical support for it.

Glenoid Labrum

The extent of the glenoid cavity in encased by a fibrocartilaginous glenoid labrum which continues beyond the bony rim and deepens the socket. Surrounding skeletal muscles provide most of the stability at this joint with help from their associated tendons and various ligaments.

Supination

The forearm is supinated in anatomical position. Turns the wrist and hand from palm facing back to facing front.

Opposition

The movement of the thumb toward the surface of the palm or the pads of other fingers. Allows movement for grasping and holding objects between your thumb and palm.

Reposition

The movement that returns the thumb and fingers from opposition. Movement of the thumb away from the palm or fingers.

Angular Movement

The movements which change the angle between the shaft and the desktop. Any angular movement can be described with reference to the same two axes (forward-backward, left-right) and the angular change (in degrees).

Ball-and-Socket Joints

The round head of one bone rests within a cup shaped depression in another. All combinations of angular and rotational movements, including circumduction, can be performed at ball-and-socket joints.

Vertebral End Plates

These thin end plates are composed of hayline cartilage and fibrocartilage. Covers the superior and inferior surfaces of discs.

Synovial Tendon Sheaths

Tubular bursae that surround tendons where they cross boney surfaces.

Pronation

Turns the wrist and hand from palm facing front to palm facing back.

Gliding Movement

Two opposing surfaces slide past one another. Ex) Carpal bones, tarsal bones, and between the clavicles and sternum. Rotation prevented by the capsule and associated ligaments.

Depression

When a structure moves in a inferior direction. Ex) You depress your mandible when you open your mouth. Lowering your shoulders in a shrug.

Elevation

When a structure moves in a superior direction. Ex) You elevate your mandible when you close your mouth. Lifting your shoulders in a shrug.

Slipped Disc

When the compressed nucleus pulposus may distort the anulus fibrosus, forcing it partway into the vertebral canal.

Herniated Disc

When the nucleus pulposus breaks through the anulus fibrosus, it too may protrude into the vertebral canal. Sensory nerves are distorted and the protruding mass can also compress the nerves passing through the adjacent intervertebral foramen.

Acetabular Labrum

Within the acetabulum a pad of fibrocartilage extends like a horseshoe to either side of the acetabular notch. A projecting rim of fibrocartilage increasing the depth of the joint cavity.