Exam 2 Articulations

Functional Classes

Movement

Synarthroidal

Amphiarthroidal

Diarthroidal

Synarthroidal

immobile

Amphiarthroidal

slightly mobile

Diarthroidal

freely mobile

Structural Class

material that joins bone

Fibrous

Fibrous

No joint cavity

Fibrous CT joins bones

Cartilaginous

No joint cavity

Cartilage joins bone

Synovial

Joint cavity

Ligaments connect bone

Diarthroidal / Synovial Joints

Diarthroidal = freely mobile

Synovial = joint cavity filled with synovial fluid. Ligaments connect bone.

Upper and Lower extremity joints

Ellipsoidal

Hinge

Ball and socket

Gliding

Pivot

Saddle

Diarthroidal / Synovial Structure

Articular cartilage

Synovial (joint) cavity

Joint (articular) capsule

Synovial fluid

Articular cartilage

hyaline cartilage that lines the ends of the bone to create a smooth surface and prevent bone rubbing on bone

Synovial (joint) cavity

space that holds the synovial fluid between the articular cartilage and bones.

Acts as lubricant to reduce friction and shock absorber, smoother movement, nourishes the articular cartilage.

Articular (joint) capsule

Fibrous capsule - dense irregular CT strengthens the joint to keep bone together. Since the CT opposes tension in any direction

Synovial membrane - creates and secretes synovial fluid. When pressure is placed on the joint, the joint compresses, blood vessels in the membrane are squeezed and leak the fluid (a filtrate of blood).

Ligaments in Synovial Joints

Reinforce and strengthen synovial joints

Dense regular CT (resists in 1 direction)

Ligaments on medial or inferior side

prevent excessive abduction

Ligaments on lateral or superior side

prevent excessive adduction

Ligaments on anterior side

prevent excessive extension and lateral rotation

Ligaments on posterior side

Prevent excessive flexion and medial rotation

Knee Ligaments

Fibular/Lateral Collateral Ligament

Prevents lateral sliding of tibia

Tibial/Medial Collateral Ligament

Prevent medial sliding of tibia

Anterior Cruciate Ligament

Prevent anterior sliding of tibia

Posterior Cruciate Ligament

Prevent posterior sliding of tibia

Posterior Meniscofemoral Ligament

anchors lateral meniscus

prevents posterior sliding of tibia (backup to PCL)

Nerves and vessels in Synovial Joint

Innervated articular capsule - detect pain if bone/joint is moved too far

Vascular supply - in synovial membrane to secrete synovial fluid

Articular discs

Meniscus in knee

For when articulating bones have very different shapes

Fibrocartilage that creates extra protection, cushion femur to tibia connection, and stability of joint

Bursae

sac-like cushions filled with synovial fluid. CT lined w/ synovial membrane.

btw skin & bone, tendon & bone, and ligament & bone

In areas of high movement like elbow

Allows smooth gliding, absorb shock, secrete synovial fluid for lubricant

Bursitis

Inflammation of an injured bursa. Walls thicken and excess fluid is secreted. Like in elbow (olecronon) and knee (prepatellar).

Can regen and heal

Tendon Sheath

An elongated bursae that wraps around tendon to reduce friction where tendons run in a confined space. (wrist, ankle, finger, toes) Carpal tunnel.

Sprain

Ligament, joint

Strain

Tendon, muscle

Osgood - Schlatter’s Disease

swelling, soreness

strong quadriceps muscle pulling on tibial tuberosity

young people in growth spurts (remodeling)

can have permanent effects

Carpal tunnel

Tendon sheaths swell, compress median nerve in tunnel.

Trigger finger

Tendon or sheath swells

sliding of tendon is limited, pop instead causing pain.

Arthroscopy

remove torn knee cartilage and repair ligaments

3 small incisions

Arthroplasty

Replace joint surgically w/ metal, ceramic, plastic

Hip and knee common

Orthopedic surgeon

Osteoarthritis

Degenerative joint disease

Most common form of arthritis

Cartilage worn down, bone spurs

Non-inflammatory (no swelling)

Leading cause of disability in elderly

Rheumatoid arthritis

autoimmune

attack cartilage

inflammation, swelling, etc. joint fusion, deform and dislocate fingers.

Gouty arthritis

Metabolic

Build-up of soidum urate crystals in blood that precipitate out in joints

common in middle-aged men with abnormal gene

bones fuse

big toe

Lyme Disease

bacterial, deer ticks

swelling and fluid build up in large joints (like knee)

fever and rash

treat w/ antibiotics