Joints: Point of contact between * 2 bones * bones + teeth * bones + cartilage **Structural Classification:** - Based on presence of synovial cavity + type of tissue **Fibrous Joints:** * Lack synovial cavity * Dense regular connective tissue present * Little or no movement (Synarthrosis) Examples: * Sutures: thin layer of dense regular * Gomphoses: tooth, ligament, dense regular * Syndesmoses: interosseous membranes, sheet of dense regular **Cartilaginous Joints** **SYNCHONDROSES** * Lack synovial cavity * Hyaline cartilage present * Little or no movement Examples: * Epiphyseal Plate: joint between rib & sternum **Cartilaginous Joints** **SYMPHYSES** * Lack synovial cavity * Fibrocartilage present * Slight movement possible (Amphiarthrosis) Examples: * Pubic symphysis * Intervertebral joints **Synovial Joints:** * Synovial cavity present (lubricates + nourishes joint) * Freely movable (Diarthrosis) * Articular cartilage: * Covers articulating surfaces, reduces friction * Articular capsule: "sleeve" that covers entire joint * Menisci: extra pads of cartilage, ↑ fit * Bursae: sac-like, contain synovial fluid + cushion joint * Accessory ligaments: * Extracapsular * Intracapsular * Nerve supply: sensory + motor information **Types of movements:** 1. Gliding: no real change in angle between bones * e.g., intercarpal movement Text from the Image: Types of Synovial Joints Planar Joints: Side-to-side & back-forth movements E.g., intercarpal, intertarsal joints Hinge Joints: Convex surface fits into concave surface Permits flexion & extension E.g., elbow, knee Pivot Joints: Rounded surface fits into ring formed by ligament or bone Permits rotation E.g., radioulnar joint Condylar Joints: Articulating bones shaped like a projection + depression Permits flexion, extension, abduction, adduction E.g., knee, temporomandibular joint Saddle Joint: Articulating bones shaped like a rider in a saddle Permits multiaxial movements E.g., thumb (carpometacarpal joint) Ball-and-Socket Joint: Only 2 examples (hip, shoulder) Range of Motion (ROM) Factors affecting ROM: Structure/shape: complementary fit = ROM Ligament strength/tension: tension = less ROM Muscle arrangement/tension: reinforces tension Contact of soft parts: limits ROM Hormones: may alter PROM Disuse: limited mobility & ROM Hinge Joint (Elbow) Hinge joints formed by: trochlea of humerus, trochlear notch of ulna, head of radius Movements: flexion, extension, rotation Alignment components: Ulnar collateral: deepens socket for trochlea Radial collateral: increases stability Anular ligament: forms ring around head of radius