Chapter 9: Joints

Homeostasis Holds bones together while allowing for movement Called articulations Point of contact between 2 bones

Structural Classification Based on the type of CT that binds the bones together & on whether there is a space (synovial cavity) or not between the bones Fibrous No synovial cavity Held together by dense irregular CT Cartilaginous Held together by cartilage Synovial Have synovial cavity Held together by dense irregular CT & possibly by accessory ligaments

Functional Classification Based on how much movement is present at joint Synarthrosis Immovable Amphiarthrosis Slightly movable Diarthrosis Freely movable They are all synovial jts

Fibrous Joints Permit little to no movement Sutures Syndesmosis Gomphosis

Table 9-1 Functional and Structural Classifications of Joints (Part 1 of 3).

Table 9-1 Functional and Structural Classifications of Joints (Part 2 of 3).

Cartilaginous Joints Permits little to no movement Synchondrosis Symphysis

Table 9-1 Functional and Structural Classifications of Joints (Part 1 of 3).

Table 9-1 Functional and Structural Classifications of Joints (Part 2 of 3).

The Structure of a Synovial Joint Medullary cavity Spongy bone Periosteum Components of Synovial Joints Joint capsule Synovial membrane Articular cartilages Joint cavity containing synovial fluid Metaphysis Compact bone a Synovial joint, sagittal section

Figure 9-1b The Structure of a Synovial Joint. Quadriceps tendon Patella Accessory Structures of a Knee Joint Joint capsule Femur Synovial membrane Bursa Fat pad Joint cavity Articular cartilage Meniscus Ligaments Tibia Extracapsular ligament (patellar) Intracapsular ligament (cruciate) b Knee joint, sagittal section

Figure 9-2 Joint Movement.

Figure 9-3 Angular Movements. Extension Flexion Hyperextension Abduction Flexion Abduction Flexion Hyper- extension Adduction Adduction Extension Extension Abduction Flexion Hyperextension Abduction Adduction Adduction Extension Flexion/extension b Abduction/adduction a Adduction Abduction Circumduction c Adduction/abduction d

Figure 9-4b Rotational Movements. Supination Pronation b Supination Pronation

Figure 9-5 Special Movements. Dorsiflexion (ankle flexion) Plantar flexion (ankle extension) Eversion Inversion Opposition Retraction Protraction Depression Elevation Lateral flexion

Figure 9-6 Intervertebral joints. Superior articular process Superior articular facet Intervertebral Disc Intervertebral foramen Vertebral end plate Intervertebral Ligaments Anulus fibrosus Ligamentum flavum Nucleus pulposus Spinal cord Posterior longitudinal ligament Spinal nerve Interspinous ligament Supraspinous ligament Anterior longitudinal ligament a Anterior view b Lateral and sectional view

Clinical Note 9-1 Damage to Intervertebral Discs. Normal intervertebral disc L1 Compressed area of spinal nerve Bulging disc Spinal nerve Spinal cord Nucleus pulposus of herniated disc Anulus fibrosus L2 a A lateral view of the lumbar region of the spinal column, showing a bulging intervertebral disc b A sectional view through a herniated disc, showing the release of the nucleus pulposus and its effect on the spinal cord and adjacent spinal nerves

Figure 9-7 The Shoulder Joint. Ligaments Stabilizing the Shoulder Joint Subcoracoid bursa Tendon of biceps brachii muscle Clavicle Acromioclavicular ligament Subacromial bursa Coracoclavicular ligaments Acromioclavicular ligament Coracoacromial ligament Coracoclavicular ligaments Muscles and Tendons of the Rotator Cuff Acromion Coracoacromial ligament Tendon of supraspinatus muscle Clavicle Tendon of supraspinatus muscle Coracohumeral ligament (cut) Acromion Articular capsule Glenohumeral ligaments Tendon of infraspinatus muscle Coracoid process Subdeltoid bursa Subscapular bursa Scapula Teres minor muscle Glenoid cavity Synovial membrane Glenoid labrum Articular cartilages Subscapularis muscle Articular capsule Humerus Joint cavity Glenoid labrum Scapula Articular capsule a Anterior view, frontal section b Lateral view of pectoral girdle

Figure 9-8 The Right Elbow Joint Showing Stabilizing Ligaments. Humerus Radial collateral ligament Radial tuberosity Antebrachial interosseous membrane Radius Ulna Capitulum Annular ligament (covering head and neck of radius) a Lateral view Tendon of biceps brachii muscle Annular ligament Humerus Articular capsule Antebrachial interosseous membrane Medial epicondyle Ulnar collateral ligament Radius Ulna Olecranon of ulna Medial view b

Figure 9-9 The Right Hip Joint. Iliofemoral ligament Articular cartilage Acetabular labrum Ligament of the femoral head Acetabulum Transverse acetabular ligament (spanning acetabular notch) Fat pad in acetabular fossa a A lateral view with the femur removed Pubofemoral ligament Iliofemoral ligament Greater trochanter Ischiofemoral ligament Iliofemoral ligament Lesser trochanter Greater trochanter b An anterior view Lesser trochanter Ischial tuberosity c A posterior view, showing additional ligaments that add strength to the capsule

Figure 9-10 The Right Knee Joint. Patellar surface Quadriceps tendon Ligaments that Stabilize the Knee Joint Posterior cruciate ligament Lateral condyle Joint capsule Medial condyle Anterior cruciate ligament Patella Patellar retinaculae Tibial collateral ligament Menisci Fibular collateral ligament Medial Patellar ligament Tibia Cut tendon of biceps femoris muscle Lateral Fibula Fibula Tibia a Anterior view, superficial layer b Deep anterior view, flexed Plantaris muscle Gastrocnemius muscle, lateral head Gastrocnemius muscle, medial head Femur Femur Ligaments that Stabilize the Knee Joint Anterior cruciate ligament Fibular collateral ligament Posterior cruciate ligament Bursa Medial condyle Lateral condyle Menisci Tibial collateral ligament Joint capsule Lateral Fibular collateral ligament Medial Popliteal ligaments Cut tendon Cut tendon of biceps femoris muscle Popliteus muscle Tibia Tibia Fibula Fibula c Posterior view, superficial layer d Deep posterior view, extended

Figure 9-11 diagrams the functional relationships between the skeletal system and the other body system we have studied so far. SYSTEM INTEGRATOR Body System Skeletal System Skeletal System Body System Synthesizes vitamin D3, essential for calcium and phosphorus absorption (bone maintenance and growth) Provides structural support Integumentary Integumentary The SKELETAL System The skeletal system provides structural support and protection for the body. The skeleton also stores calcium, phosphate, and other minerals necessary for many functions in other organ systems. In addition, the lipids in the yellow bone marrow serve as an energy reserve and blood cell production occurs in the red bone marrow. Muscular Page 380 Nervous Page 558 Endocrine Page 647 Cardiovascular Page 776 Lymphatic Page 824 Respiratory Page 874 Digestive Page 929 Urinary Page 1010 Reproductive Page 1090

Table 9-1 Functional and Structural Classifications of Joints (Part 3 of 3).

Table 9-2 Joints of the Axial Skeleton (Part 1 of 3).

Table 9-2 Joints of the Axial Skeleton (Part 2 of 3).

Table 9-2 Joints of the Axial Skeleton (Part 3 of 3).

Table 9-3 Joints of the Appendicular Skeleton (Part 1 of 2).

Table 9-3 Joints of the Appendicular Skeleton (Part 2 of 2).