تشريح الملزمة الرابعة PDF

# Articulations ## كلية دجلة ## مدرس المادة .... زيد زياد عدنان ### Articulations or Joints * **Place where two bones come together** * **Freely movable to limited to no apparent movement** * **Structure correlated with movement** ### Named * According to bones or parts united at joint * Accord...

# Articulations ## كلية دجلة ## مدرس المادة .... زيد زياد عدنان ### Articulations or Joints * **Place where two bones come together** * **Freely movable to limited to no apparent movement** * **Structure correlated with movement** ### Named * According to bones or parts united at joint * According to only one of articulating bones * By Latin equivalent of common name ### Types of Joints: Based structure and function * **Fibrous (Immovable)**, e.g., sutures in skull, Tibiofibular ligament. * **Cartilaginous (Slightly movable)**, e.g., Costal cartilage-sternum, Pubic symphysis, Intervertebral disc. ## Fibrous Joints ## Cartilaginous Joints ## Synovial: * Most common joints in body * Most mobile joints * Have articular surfaces on bone with hyaline cartilage, completely enclosed joint capsule formed from ligamentous connective tissue, **Synovial fluid** within capsule lubricates joint * Some have meniscus or articular disc (e.g., knee, jaw joint) ## Functions of synovial fluid * **Lubrication:** With articular cartilage compression, synovial fluid is squeezed out and reduces friction between moving surfaces * **Synovial fluid distribution:** Provide nutrients and oxygen, as well as waste disposal for the chondrocytes of articular cartilages and compression and re-expansion of articular cartilages pump synovial fluid in and out of cartilage matrix * **Synovial fluid absorption:** Distributes compression forces across articular surfaces and outward to joint capsule ## Types of Synovial Joints 1. Plane or gliding 2. Saddle 3. Hinge 4. Pivot 5. Ball-and-socket 6. Ellipsoid ## Ligaments * strengthen, and reinforce joint * separate from joint capsule * may pass inside *(intracapsular)* or outside *(extracapsular)* the joint capsule. * intracapsular example: cruciate ligaments. * extracapsular example: patellar ligament.