- additional receptors: detect potentially damaging stimuli (excessive pressure or stretch) and are responsible for theperception of pain
- articular cartilage: (usually hyaline cartilage) smooth, thin layer on the surface of the bones (approx. 1/2 cm thick)
- biaxial: (type of synovial joint) motion occurs in 2 planes, around 2 axes (2 degrees of freedom): condyloid joints and saddle joints
- bursae: sacs of synovial fluid that are located outside of the joint; used to reduce friction btwn moving tissues
- cartilaginous joints: bone-cartilage-bone connection
- condyloid joints: one joint surface is convex and the other is concave
- diarthroses (synovial joints): allow significantly more movement than synarthroses
- dynamic proprioception: knowing which direction a limb is moving with eyes closed
- dynamic stability: provided by the muscles (moving or responding to something)
- extrinsic ligaments: located outside the joint capsule (ligaments on side of the ankles)
- fibrocartilage: contains bundles of collagen fibers; better to withstand shearing and torsional forces
- fibrous joints: fibrous tissue that connect bone to bone
- fibrous layer: the layer that limits joint motion
- functions of articular cartilage: reducing friction, and absorbing and distributing forces of compression
- functions of synovial fluid: (1) provides nutrients to articular cartilage and (2) lubricates joints and reduces friction
- gomphosis: bones fit together like a peg in a hole, secured by fibrous tissue (teeth)
- hinge joints: allow mostly flexion and extension (fingers and elbows)
- hyaline cartilage: "glass-like" cartilage designed for compression
- intrinsic ligaments: form part of the joint capsule or are located inside the joint (ACL)
- joint capsule: provides stability to the joint and contains the synovial fluid
- joint innervation: joint receptors in the ligaments and joint capsules provide proprioceptive information
- joint motion: required so that the synovial fluid circulates
- ligaments: fibrous tissue that connects bones to provide stability to joints
- nonaxial: (type of synovial joint) relatively flat surfaces that allow linear motion only (translation or gliding): plane joints
- pivot joints: allow mostly rotation (movement of radius during pronation and supination)
- proprioception: an ability to know the position of your body and to detect movement with eyes closed; located in the ligaments
- saddle joints: each joint surface is convex in one direction and concave in another direction
- stability vs mobility: almost always an inverse relationship
- static proprioception: know where limbs are in space
- static stability: provided by the shape of the bones, the ligaments, and joint capsules
- sutures: bone edges interlock or overlap each other and are connected by a ligament or membrane; only found in the skull and allow a small amount of movement for childbirth and growth, there is no movement in adulthood
- symphysis: bone-hyaline-fibrocartilage-hyaline-bone; mostly designed for weightbearing, but allows some movement (intervertebral joints and symphysis pubis in the pelvis)
- synarthroses: consist of fibrous and cartilaginous joints
- synchondrosis: bones are joined by hyaline cartilage only (btwn sternum and first rib)
- syndesmosis: greater distance btwn bones than other fibrous joints; are connected by a ligament or a membrane that allows some movement (btwn ulna and radius and btwn tibia and fibula)
- synovial fluid: simialr to blood plasma, with the addition of hyaluronic acid which makes it viscous (oil-like)
- synovial membrane: inner layer that produces the synovial fluid
- triaxial: (type of synovial joint) motion occurs in 3 planes, around 3 axes (3 degrees of freedom): ball & socket joints (hip and shoulder)
- uniaxial: (type of synovial joint) motion is allowed mostly in one plane, around one axis (hinge joints and pivot joints)