Types of Joints😍

Types of Joints

Fibrous Joints

• Also called Synarthrosis

• Bones connected by fibrous connective tissue

• Allow little to no movement

• ”Mneumonic: SuSy Ddi.. (Suture, Syndesmosis) Go (Gomphosis) eat Fibre

Types:

1. Sutures

• Between cranial bones

• Immovable

• Schindylesis – special type of suture

• Mneumonic: Skin (Schindylesis) il Suture

2. Gomphosis

• Tooth and socket joint

• Dento-alveolar joint

3. Syndesmosis

• Bones joined by ligament/interosseous membrane

• Interosseous membrane
• Undergoes ossification in Fluorosis

• Provide stability

• Examples:
• Middle Radioulnar Joint
• Inferior Tibiofibular Joint
• Sacro - iliac joint
• 1st Chondrosternal Joint

• MR () IT () SIr () is Desp (syDesmosis) → 1st chondrosternal injury

Cartilaginous Joints

• Bones connected by cartilage

Types:

• Primary Cartilaginous
• aka Synchondrosis
• Connected by hyaline cartilage
• Immovable
• Temporary → undergo synostosis
• Examples:
• Epiphysis-diaphysis joint
• Costochondral joint
• Spheno-occipital joint
• ED COCO SO

Radioulnar Synostosis

• Secondary Cartilaginous
• aka Symphysis
• Hyaline cartilage on surfaces + joined by fibrocartilage
• Allow limited movement
• Occur in midline (except mandibular)
• Examples:
• Intervertebral disc
• Sacro-coccygeal joint
• Pubic symphysis
• Manubriosternal joint
• Xiphisternal joint (some authors list as synchondrosis)

Synovial Joints

• Im () sad () 1st cmc () sc () kondupoi only cc ()

• Also called Diarthrosis

• Have:
• Synovial cavity
• Articular cartilage
• Joint capsule
• Synovial fluid

• Allow movement

1. Ball & Socket Joint

• Shoulder joint

• Hip joint

• Incudo-stapedial joint

• Talo-calcaneo-navicular joint

2. Hinge Joint

• Movement in one plane – flexion/extension

• Examples:
• Elbow
• Knee / Ankle
• Interphalangeal joints
• Talo-crural - Ankle
• Kruramayitt Thala (Talocrural) door Hinge (hinge joint) vach idich

3. Saddle Joint

• Opposing surfaces = concave + convex

• Examples:
• 1st Carpometacarpal joint (thumb)
• Sternoclavicular joint
• Incudomalleolar joint
• Calcaneocuboid joint
• Kneecap (Femur-Patella articulation)

• ”Mneumonic: IM (Incudomalleolar joint) SAD (Saddle) → [bcz i fell → parts injured] → sternum (Sternoclavicular joint), thumb base (1st Carpometacarpal joint (thumb)), knee (Kneecap), back foot (Calcaneocuboid joint)“

• Im () sad () 1st cmc () sc () kondupoi only cc ()

4. Ellipsoid Joint (Condyloid Joint)

• Biaxial movement – flexion/extension + abduction/adduction

• Examples:
• Tell Vaada with
• Fingers → Radiocarpal (Wrist) joint
• Wrist → Metacarpo-phalangeal joints
• Foot →Metatarso-phalangeal joints
• Head (nod) → Atlanto-occipital joint

• Atlanto-occipital joint
• Allows flexion and extension
• ”Mneumonic: Elimayode (Ellipsoid) Aoo Aoo Aoo

5. Condylar Joint

• Subtype of synovial

• Examples:
• TM Joint
• Knee joint

6. Plane Joint

• Allow sliding/gliding

• Examples:
• Acromioclavicular joint
• Superior Tibiofibular joint
• Costovertebral joint
• Chondrosternal joints after 1st
• Intercarpal and Intertarsal joints
• Costotransverse joint
• between the rib and vertebra
• 8th and 9th rib attachment to 7th rib

• Attach different planes with midline
• Clavicle → acromion
• Rib → Vertebre
• Rib cartilage → sternum

7. Pivot Joint

• Rotation around single axis

• Examples:
• Superior & Inferior Radioulnar joints
• Atlanto-axial joint
• Movements:
• Allows rotation of head
• Skull and atlas unit rotate on axis joint.
• ”Mneumonic: AA → @ → round round
• Clinical Note
• Degenerative changes seen in
• Rheumatoid arthritis
• Downs syndrome

Cartilage in Joints

Articular cartilage

• Usually Hyaline cartilage

• Features:
• No perichondrium
• Avascular
• Poor nerve supply
• Cannot regenerate
• Contains collagen type 2 + proteoglycans

Fibrocartilage

• Found in:
• Intervertebral disc
• Articular disc
• Meniscus
• Glenoid labrum

• Type 1 collagen

Muscle Fiber Arrangement