Arthrology Study of Joints

Structural Joint Classifications Based on anatomical characteristics Presence/absence of joint cavity Type of connective tissue that binds them Types Fibrous joint Cartilaginous joint Synovial joint

Fibrous Joints Lacks a synovial cavity Bones are held together by fibrous connective tissue Permit little to no movement Types Sutures Syndesmoses Gomphoses

Cartilaginous Joints Lacks a synovial cavity Allows little or no movement Types Synchondroses Symphyses

Synovial Joints Joint cavity present Articular cartilage Articular capsule Synovial membrane Fibrous membrane Synovial fluid Ligaments Intracapsular Extracapsular

Types of synovial joints Ball and socket joint Hinge joint Saddle joint Pivot joint Gliding joint Condyloid joint

Functional Joint Classifications Based on type of movement they permit Types Synarthrosis-Immoveable joint Sutures Amphiarthrosis-Slightly moveable joint Intervertebral joints Diarthrosis-Freely moveable joint Shoulder, knee

Synarthrodial Joint Immovable joint Fibrous joint which can attenuate force with little or no movement Examples Sutures Syndesmoses: radioulnar, tibiofibular

Synarthrodial Examples

Amphiarthrodial Joint Cartilagenous joint which attenuates forces Examples Synchondroses: SC Joint Symphysis: Vertebral Joint, Pubic symphysis

Amphiarthroidal Examples

Diarthrodial Joint Provides mobility by permitting one body segment to rotate about another. Transmits forces from one segment to another.

Diarthrodial Joint Anatomy Articular Cartilage Articular Capsule Fibrous membrane Synovial membrane Synovial Fluid Ligament

Diarthroidal Examples

Diarthroidal Examples ctd

Stability Maintaining Joint integrity Provided By: Joint construction Ligaments Capsule Tendons Gravity

Flexibility The range of movement within a joint. Affected By: Shape of the articular surface Muscle mass Bony blocks Muscle length/flexibility Ligament length/flexibility Age

Range of Motion (ROM) Types: AROM PROM

Levers Any elongated, rigid object that rotates around a fixed pointed called a fulcrum. Rotation occurs when an effort applied to one point on the lever overcomes a resistance located at some other point.

Lever Components

Levers and Mechanical Advantage The function of a lever is to impart an advantage. Advantages can be either: Exert more force against a resisting object than the force applied to the lever, for example: moving a boulder with a crowbar. Move the resisting object farther and faster than the effort arm is moving.

Classes of Levers Determined by which component (fulcrum, effort, resistance) is in the middle Class I: Balance Class II: Strength Class III: Speed/ROM

1st Class Lever Examples

2nd Class Lever Examples

3rd Class Levers Examples