Lecture 6 - Shoulder and Elbow Joints Flashcards
Joints/articulations
Sites where 2 or more bones meet to provide stability and/ormobility to the skeleton
How are joints classified
1) Functionally: Immovable, slightly movable or freely moveable
2) Structurally: Fibrous, cartilaginous or synovial
Fibrous Joints
Connected by dense regular connective tissue that lack a joint cavity
3 types of fibrous joints
- Sutures
- Syndesmoses
- Gomphoses
Sutures
Located between skull bones; immovable
Syndesmoses
Connected by ligaments; movement range depends on length
Gomphoses
Peg-in-socket joint for root of tooth
Cartilaginous Joints
Bones united by cartilage; lack of joint cavity
2 types of cartilaginous joints
- Synchondroses
- Symphyses
Synchondroses
Hyaline cartilage; immovable
Symphyses
Fibrocartilage; slightly moveable
Synovial Joints
Fluid- filled joint cavity; many are freely moveable joints
Synovial joints are described according to
degrees of movement or shape
Articulating surface of bone is covered by
hyaline cartilage
Synovial membrane produces
synovial fluid that lubricates joint
Outer surface of synovial joints are made of
fibrous capsule
What are 3 additional structures that make up synovial joints:
1) articular disc
2) labrum
3) burse
T or F: Synovial joint that includes an articular disc divides the joint into two cavities, each with their own synovial membrane
T
T or F: Movement at joint does not allow for great reach at upper limb
F, it does
The acromioclavicular joint is weak so how is it strengthened
Extrinsic (coracoclavicular) ligaments
T or F: Synovial joints permit sliding/gliding at the acromioclavicular joint
T
The shoulder joint (glenohumeral) consists of
1) Scapula
2) Humerus
3) 4 ligaments to support shoulder joint
What are the 4 ligaments of the shoulder joint
Laxity at axillary pouch permits
abduction
Coracoacromial ligament is strong and it is implications for
fractures
Glenoid labrum helps to
Deepen the fossa for added mobility and fossa
Label the missing parts of the shoulder joint
Bursae
Sac-like cavities lined by a synovial membrane to reduce friction between adjacent structures
Bursitis
Inflammation of the bursae
Label the missing parts of the bursae in the shoulder joint
Function of rotator cuff at shoulder joint
Rotator cuff muscles secure the head of the humerus to provide joint stability
Label the missing parts of the rotator cuff
How does a clavicular fracture occur
Fracture occurs from traumatic upward force of the humerus
How does the acromioclavicular ligament dislocate
Downward/Inward force applied to acromion can rupture ligaments associated with acromioclavicular joint
What can cause dislocation of humerus
LAteral rotation and excessive extension
Label the missing elbow bones and joints
What movement happens at the ulnar-humeral joint
Flexion/extension
What movement occurs at the radio-humeral joint
Flexion/extension
What movement occurs at the proximal radio-ulnar joint
Pronation/supination
Label the missing ligaments of the elbow
What are the 3 ligaments of the elbow
- Ulnar collateral Ligament (Superior, Oblique, and inferior)
- Annular Ligament
- Radial Collateral Ligament
Function of the ulnar collateral ligament
Superior and oblique provide stability to medial elbow while the inferior deepens socket for the trochlea of the humerus (better stability than what bones can provide themselves in the olecranon process)
Function of the annular ligament
Allows pivoting of head of radius in radial-ulnar joint
