2.11.Joints of the upper limbs

Question 1

what forms a joint?

what attaches bone to bone?

joints in classes. list feature and associated subtypes

Answer 1

two bones articulating with eachother

ligaments

3classes

1. fibrous
   
   1. immovable bones are attached by dense connecrive tissue (fibrous tissue)
   2. types
      
      1. suture
      2. gomphosis
      3. syndesmosis
2. cartilaginous
   
   1. two bones are joined by cartilage
   2. two types
      
      1. primary(synchondrosis)
      2. secondary(symphysis)
3. synovial
   
   1. movment is restricted by muscles and ligaments
   2. three class of levers

Question 2

slide 3

Answer 2

1. fibrous tissue that connects bones together
2. a fold of peritoneum, or other membrane
3. the remnants of a tubular structure from the fetal period of life

Question 3

Describe immobile joints. list subtypes, facts and examples

Answer 3

1. immovable
   
   1. bones are attached by dense connective tissue
      
      1. fibrous tissue
2. three types of fibrous joints
   
   1. suture
      
      1. bones of skull
   2. gomphosis
      
      1. peg fits into socket
      2. example
         
         1. teeth
   3. syndesmosis
      
      1. joining of two bones by an interosseous membrane
      2. permits slight movement
      3. example
         
         1. interosseous membrane between tibia-fibia and radius-ulna

Question 4

define cartilagenous joints, structure, function and subtypes

Answer 4

1. cartilagenous joints
   
   1. struture
      
      1. two bones are joined by cartliage
   2. mobility
      
      1. more mobile than fibrous joints
   3. types
      
      1. primary(synchondrosis)
         
         1. bones are connected by hyaline cartilage
         2. example
            
            1. sternocostal joint
            2. fusion of long bones
      2. secondary (symphisis)
         
         1. fibrocartilaginous joints
         2. example
            
            1. pubic symphysis
            2. intervertebral disks

Question 5

define synovial joints, structure, function and types.

Answer 5

synovial joints

1. structure
   
   1. enclosed by a noint capsule, lines with synovial membrane
      
      1. secretes synovial fluid that lubricates an nouriches articulating surfaces
   2. free mobile joints
      
      1. movment is restricted by muscles and ligaments
   3. articular surface of bones
      
      1. coverd in hyaline cartilage
2. function
   
   1. all range of motion
   2. increase felxibility = incresase instability
3. types-add in examples
   
   1. plane
   2. saddle
   3. hinge
   4. ball and socket
   5. pivot
   6. condyloid
   7. ellipsoid

Question 6

bones act as ____, joints act as _________.

explain the orders

Answer 6

bones act as the lever, joints act as the folcrum.

1. 3 orders of levers based on
   
   1. fulcrum position, direction and position of effort exerted
   2. resistance is always in the direction of gravity
   3. class of levers
      
      1. ​first class
      2. second class
      3. third class

Question 7

joints of the upper limb

Answer 7

Question 8

what happens with the highly mobile upper limb? is there an expense

Answer 8

the upper limb is highly mobile for positioning the hand in space

1. increase mobility=decrease stability

Question 9

how do muscles act on joints?

muslces work ______ to create movement.

Answer 9

muscles act on joints they cross

1. muscle attachments and orientation of muscle fibers determine action of muscle

muslces work together to create movement.

1. agonis/antagonist
2. synergist

Question 10

what are the joints acting on the shoulder?

Question 11

describe the articulation, structure and motion of the sternoclavicular joint

Answer 11

1. sternoclavicular joint
   
   1. articulation
      
      1. manubrium of sternum
      2. clavicle
   2. structure
      
      1. synovial joint with an articular disc
      2. ligaments
         
         1. interclavicular ligament
         2. anterior and posterior sternoclavicular ligaments
         3. costoclavicular ligaments
      3. muscles
         
         1. none
   3. motions
      
      1. predominantly in the anteroposterior and vertical planes
      2. some rotation

Question 12

define the joint, articulation, structures, joint type and motions

Answer 12

1. acromioclavicular joint
   
   1. articulation
      
      1. acrominon process of the scapula
      2. clavicle
   2. structure
      
      1. synovial joint
      2. ligament
         
         1. acromioclavicular ligament
         2. coracoclavicular ligament
            
            1. trapezoid ligament
            2. conoid ligament
      3. muslces
         
         1. no muscle “crosses” the joint and acts on it
   3. motion
      
      1. anteroposterior and vertical planes
      2. some light axial rotation

Question 13

BMX rider presents in the ER with the following signs.

talk about the cause and grades

Answer 13

1. shoulder seperation
   
   1. cause
      
      1. injury to acromioclavivular and/or coracoclavicular ligaments
         
         1. weight of upper limb pulls scapula and acromion inferioly below clavicle
            
            1. clavicle overides acromion (piano key sign)
      2. ac moint is relatively weak to allow for mobility
         
         1. integrity/strength of joint predominantly from coracoclavicular ligament
   2. grades
      
      1. partially stretched AC ligament
         
         1. coracoclavicular ligaments intact
      2. torn AC ligament with some discplacement
         
         1. coracoclavicular ligaments intact
      3. copmlete seperation of joint. AC and coracoclavicular separation of joint.
         
         1. AC and coracoclavicular ligaments are torn
      4. 4-6
         
         1. very uncommon involving other joints

Question 14

Answer 14

Question 15

Answer 15

Question 16

define joint, list structures, structures, functions and location (for ligaments)

Answer 16

1. glenoid labrum
   
   1. structure
      
      1. fibrocartilaginous
      2. deepens glenoid cavity
   2. function
      
      1. creates vaccum effect
      2. w/o labrum
         
         1. glenohumeral stability decrease by 20%
2. capsule
   
   1. structure
      
      1. attaches from glenoid cavity to anatomical neck of humerus
   2. function
      
      1. least amount of support inferiorly
3. ligaments
   
   1. coracoacromial (CAL)
      
      1. ​location
      2. function
         
         1. helps resist upward displacment of the head of humerus
   2. coracohumeral (CHL)
      
      1. ​location
      2. function
         
         1. strengthens superior portion of capsule
         2. some support during should abduction
   3. transverse humeral ligament
      
      1. ​location
      2. function
         
         1. holds long head of biceps in the groove
   4. glenohumeral ligament
      
      1. location
         
         1. all 3 parts attach from upper margin of glenoid cavity
      2. function
         
         1. strengthen anterior portion of capsule

Question 17

Patient presents in er after wrestling match. what is the diagnosis, location, susceptibility, function and possible damage?

Answer 17

1. GH joint is most suseptible to dislocation in
   
   1. ABDUCTION AND EXTERNAL ROTATION
2. once out of the glenoid cavity, the strong pec major pulls the humerus anterosuperioly
   
   1. b/c of its position, the axillary nerve may be damaged

Question 18

define the movements and structures

Answer 18

Question 19

describe the thoraco-scapular joint articulatin, function

Answer 19

1. thoraco-scapular joint
   
   1. articulation
      
      1. posterior thoracic cage
         
         1. convex surface
      2. anterior scapula
         
         1. concabe surface
   2. function
      
      1. movment due to the superficial back muscles
         
         1. elevation/depression
         2. protaction/retraction
         3. upward/downward

Question 20

describe the photo

what is it AKA? describe pathopysioloby and signs/symptoms

Answer 20

snapping scapula aka:scapulathoracic bursitis/creptius

1. pathophysiology
   
   1. caused by bony alteration or inflamed soft tissue
   2. may be painful or painless
   3. can occur as a result of microtrauma(chronic) or macrotrauma(acute)
   4. often due to over-use injury worse with over-head movements
2. bursitis
   
   1. ​inflammation of fluid-filled sacs that cushion and reduce friction of bones, tendons, muscles
3. crepitus
   
   1. a grating sound/sensation produced by friction between bone and cartilge

Answer 21

1. epicondyles on humerus
   
   1. medial
      
      1. attachment for flexors
   2. lateral
      
      1. attachment for extensors
2. note palpable bony features
   
   1. radius
      
      1. head, body, dorsal tubrecle and styloid process
   2. ulna
      
      1. olecranon, posterior border, head, and styloid process of the ulna
   3. metacarpal bones and phalanges.