7. joints

Articulations

• Types of Joints:

  • Fibrous Joints

  • Cartilaginous and Bony Joints

  • Synovial Joints

Specific Ligaments and Structures

• Knee Joint Ligaments:

  • Anterior cruciate ligament

  • Medial collateral ligament

  • Lateral collateral ligament

  • Medial meniscus

  • Lateral meniscus

  • Posterior cruciate ligament

Joints and Their Classification

• Arthrology: Study of joints

• Kinesiology: Study of musculoskeletal movement

• Classification by Movement:

  • Diarthrosis (freely movable)

  • Amphiarthrosis (slightly movable)

  • Synarthrosis (little or no movement)

• Classification by Connection Type:

  • Fibrous, Cartilaginous, Bony, and Synovial Joints

Classification of Joints

• Structural Classification: Based on the presence of space between bones

  • Types of connective tissue involved

  • Collagen fibers, cartilage, joint capsule, and accessory ligaments

• Functional Classification: Based on movement capability

  • Immovable = Synarthrosis

  • Slightly movable = Amphiarthrosis

  • Freely movable = Diarthrosis

Types of Joints

• Synovial Joints:

  • Separated by a joint cavity, lubricated by synovial fluid

  • Examples: Shoulder, elbow, knee

• Fibrous Joints:

  • Bones held together by collagen fibers

  • Examples: Skull sutures, teeth in sockets

• Cartilaginous Joints:

  • Bones connected by cartilage

  • Examples: Pubic symphysis, intervertebral discs

• Bony Joints:

  • Two bones fused by osseous tissue (synostoses)

Details of Fibrous, Cartilaginous & Bony Joints

• Fibrous Joints:

  • Lack a synovial cavity, held tightly by fibrous connective tissue, little to no movement

  • Three types: Sutures, Syndesmoses, Gomphoses

• Cartilaginous Joints:

  • No synovial cavity, bones connected by cartilage

  • Two types: Synchondroses (hyaline cartilage) and Symphyses (fibrocartilage)

• Bony Joints:

  • Two bones fused by osseous tissue

Fibrous Joints

• Types:

  • Sutures: Interlocking joints between skull bones

    • Serrate, Lap, Plane types

  • Syndesmoses: Bones bound by ligaments (e.g., radius and ulna)

  • Gomphoses: Tooth held by fibrous periodontal ligament

Cartilaginous Joints

• Synchondroses:

  • Joined by hyaline cartilage (e.g., rib attachment to sternum)

• Symphyses:

  • Joined by fibrocartilage (e.g., pubic symphysis)

Bony Joints (Synostoses)

• Fusion of separate bones through osseous tissue

Synovial Joint Anatomy

• Articular Capsule: Fibrous capsule lined with synovial membrane

• Synovial Fluid: Viscous fluid aiding lubrication

• Articular Cartilage: Covers joint surfaces

• Meniscus: Fibrocartilaginous pad in specific joints

• Ligaments: Connect bone to bone (types include capsular, extracapsular, and intracapsular)

Tendon Sheaths and Bursae

• Bursa: Saclike extension allowing movement between structures

• Tendon Sheaths: Cylinders wrapped around tendons

Surgical Procedures

• Arthroscopy: Joint examination and repair

• Arthroplasty: Joint replacement with prosthesis

Joint Types

• Ball-and-Socket Joints: Multiaxial joints (e.g., shoulder, hip)

• Hinge Joints: Monoaxial joints (e.g., elbow, knee)

• Saddle Joints: Biaxial joint (e.g., thumb)

• Condyloid Joints: Biaxial joints (e.g., wrist)

• Pivot Joints: Allow rotation (e.g., neck)

• Gliding Joints: Limited movement joints

Temporomandibular Joint (TMJ) Syndrome

• Symptoms include pain, headaches, and clicking sounds

Shoulder Joint (Humeroscapular)

• Most freely movable joint; supported by ligaments and rotator cuff

• Dislocations common in abducted positions

Hip Joint

• Deeply seated joint, fewer dislocations occurred

• Congenital dislocations managed by harnesses

Knee Joint

• Largest diarthrosis, primarily a hinge joint with slight rotation capability

• Stabilized by ligaments and menisci

• Complex due to joints and ligaments association

Sprain vs. Strain

• Sprain: Ligament injury without dislocation

• Strain: Muscle overstretch or partial tear

Range of Motion Factors

• Shape of bones, tension in ligaments, and muscle arrangement

Articular Cartilage

• Lacks blood supply; thickens with use; provides nourishment

Arthritis, Bursitis & Joint Replacement

• Arthritis: Inflammation and pain in joints

• Bursitis: Inflammation of bursa

• Joint Replacement: Prosthesis for diseased joints

Rheumatoid Arthritis

• Autoimmune disorder affecting synovial membrane

• Inflammation and pain, potential for joint fusion

Osteoarthritis

• Degenerative disease from aging and wear; no inflammation but cartilage loss

Gouty Arthritis

• Crystals in joints cause pain due to uric acid buildup

Infectious Arthritis

• Caused by bacteria or viruses; diagnosis requires synovial fluid aspiration