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MBS 212 Human Movement. Lecture 7 Upper limb joints Prof. Thomas K. Monsees 2008. Articulations or Joints. Articulation or Joint Place where two bones come together Structure correlated with movement Classification by function (degree of movement)
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MBS 212 Human Movement Lecture 7 Upper limb joints Prof. Thomas K. Monsees 2008 Prof. Monsees
Articulations or Joints • Articulation or Joint • Place where two bones come together • Structure correlated with movement • Classification by function (degree of movement) • Classification by structure (what is ‘between’ the articulating bones) Prof. Monsees
Joints: classification by function • i.e., by the degree of movement possible: • Synarthroses • Joints with little or no movement • Skull sutures, mental symphysis, teeth in sockets, 1st costosternal joint. • Amphiarthroses • Slightly moveable joints • Intervertebral discs, costosternal joints, pubic symphysis • Diarthroses • Freely moveable joints • Shoulder, knee, hip, elbow, interphalangeal, tarsal, and carpal joints Prof. Monsees
Classes of Joints • Structural: Based on major connective tissue type that binds bones • (Bone) • Fibrous • Cartilaginous • Synovial • Functional: Based on degree of motion • Synarthrosis: Nonmovable • Amphiarthrosis: Slightly movable • Diarthrosis: Freely movable (e.g. synovial joints) Prof. Monsees
Synovial joints • Most joints of the appendicular skeleton are synovial joints, reflecting the far greater mobility, compared with that of the axial skeleton Major synovial joints: • Shoulder, hip, elbow, knee, carpal, interphalangeal Prof. Monsees
Synovial joints • Articular cartilage on ends of bones • Bones separated by a joint cavity • Lubricated by synovial fluid secreted by synovial membrane • Enclosed in a fibrous joint capsule which holds bones together while permitting flexibility Prof. Monsees
Additional Synovial Structures • Articular disks: flat plate of cartilage located between articular cartilages of the bones; circumference is attached to fibrous capsule • Meniscus: incomplete, crescent-shaped fibrocartilage pad • Bursa: are basically bags of lubricant - fibrous membrane bags filled with synovial fluid. Bursitis: inflammation of bursa, may cause considerable pain around joint thus restricting movement • Tendon sheaths: some bursae extend along tendons • Accessory ligaments: Contribute to strength and stability of the joint while limiting movement - intrinsic lig are localized localized thickenings of the joint capsule. - - extrinsic lig are sepaerate from the joint capsule and may be located either inside or outside the fibrous capsule. Prof. Monsees
Structural classification of synovial joints • Synovial joints are described as gliding, pivot, saddle etc on the basis of the shape of the articulating surfaces • Each type of joint permits a different type and range of motion Prof. Monsees
Atlas & Axis Radiocarpal Prof. Monsees Hinge Ball & Socket
Types of Synovial Joints • Plane joints (gliding) • Articular surfaces are flat and allow short slipping or gliding movements. • Slight nonaxial or multiaxial • Intercarpal and intertarsal joints • Saddle joints • Each articular surface has convex and concave areas. Each articular surface is saddle-shaped. • biaxial • Carpometacarpal joints of the thumbs. Prof. Monsees
Sternoclavicular joint Prof. Monsees
Acromioclavicular joint Prof. Monsees
Coracoclavicular joint • Coracoid process of scapula + clavicle • Extremely powerful • 2 Parts • Conoid + trapezoid • Restrain opposite movements of scapula with respect to clavicle Prof. Monsees
a) Lat view glenoid fossa, head humerus removed coracoclavicular acromioclavicular b) Transverse humeral lig Prof. Monsees
Radio - Ulnar Articulations • As well as articulating independently with humerus at the elbow joint, radius and ulna also articulate with each other by 3 joints: • Proximal + distal ends by synovial joints superior + inferior radioulnar joints • Interosseous membrane as syndesmosis along their shafts (intermediate joint) Prof. Monsees
Radio – ulnar joints Trochlea Capitulum Head of Radius sup radioulnarj superior = proximal radioulnar j Inferior = distal Radius Ulna Interosseous M Head of Ulna Radial notch ulna inf radioulnar j Articular disc sup radioulnarj Prof. Monsees
Superior Inferior radio ulnar joint Prof. Monsees
Hand joints • Wrist • Carpal • Carpo metacarpal • Metacarpal phalangeal • Interphalangeal Prof. Monsees
Hand joints Radiograph MRT Prof. Monsees
Wrist joints Midcarpal Radiocarpal Prof. Monsees
Wrist joints (cont…) Metacarpal thumb Carpometacarpal Prof. Monsees
Wrist joints (cont…) Interphalangeal Metacarpophalangeal Prof. Monsees
Shoulder Joint Prof. Monsees
Movements of arm at shoulder joint • Abduction • Adduction • Flexion • Extension • Medial rotation • Lateral rotation • Circulation Prof. Monsees
M. supraspinatus • Origin • supraspinous fossa of scapula • Insertion • greater tubercle of humerus • Innervation • Suprascapular nerve (C5, C6) • Action • Rotator cuff • Initiation of abduction of arm to 15, than deltoid takes over posterior superior Prof. Monsees
M. Deltoideus (cont…) • Action • Major abductor of arm, abducts beyond initial 15 done by supraspinatus • Ant pt flexion + med rotation • post pt extension + lat rotation Prof. Monsees
Axes of movement at shoulder joint Scapula Humerus With respect to cardinal axis of body With respect to plane of glenoid fossa Prof. Monsees
Ligaments of Shoulder Joint Prof. Monsees
Muscles which bind humerus to shoulder girdle • M. teres major • M. deltoideus • Rotator cuff muscles • M. Supraspinatus • M. Infraspinatus • M. Teres minor • M. Subscapularis Prof. Monsees
Stability of shoulder joint: action of rotator cuff muscles • Rotator cuff muscles attach very close to should joint • + fuse w lat pt capsule act as ligaments prevent lax capsule from being trapped between artic bones Prof. Monsees
Elbow joint Prof. Monsees
Synovial membrane (ant) Elbow Joint Capsule + ligaments Prof. Monsees
Movements of elbow joint Prof. Monsees
Elbow Joint • Arteriel blood supply derived from extensive anastomosis around the elbow involving brachial artery + its terminal branches: • Sup + inf ulnar collatetral branches of brachial artery • Rad + middle collateral of profunda brachii artery • Venous drainage, by vessels accompanying above arteries, is into radial, ulnar + brachial veins Prof. Monsees
Cubital fossa: deep (a) + superficial (b) structures Prof. Monsees