Biomechanics

Question 1

Most muscles in the body are what type of lever?

Answer 1

third class (bicep)

pivot —— effort up^ ———– load v———-

Question 2

What is the convex-concave rule?

Answer 2

convex-concave movement = roll and slide are in OPPOSITE directions

Question 3

What convex or concave rule applies to the spine?

Answer 3

convex rule applies at the atlanto occipital joint

- all else below second vertebrae follow concave rule

Question 4

What is the concave rule?

Answer 4

concave on convex movement = roll and slide are in the SAME direction

Question 5

What does a firm endfeel indicate?

Answer 5

capsular and ligamentous stretching

Question 6

What does a boggy end feel indicate?

Answer 6

edema, joint swelling

Question 7

What does a muscle spasm end feel feel like?

Answer 7

rubbery

Question 8

What is the open-packed position for the GH joint?

Answer 8

55-70deg abd, 30 horizontal add, neutral rotation

Question 9

In what position should you manipulate the SC joint?

Answer 9

arm resting by side

Question 10

In what position should you manipulate the humerulnar joint?

Answer 10

70deg flex, 10deg sup

Question 11

T/F: The closed pack position of the humeroradial joint is full extension and supination.

Answer 11

false, that’s closed pack for humeroulnar

- closed for humeroradial = 90deg flex, 5deg sup

Question 12

What’s the closed pack position of the GH joint?

Answer 12

fully abducted/ERed

Question 13

In what position should you manipulate the distal radioulnar joint?

Answer 13

10deg sup

Question 14

In what position should you manipulate the knee?

Answer 14

25deg flexion

Question 15

In what position should you manipulate the MCP joints?

Answer 15

first MCP: slight flexion

all others: slight flexion and ulnar deviation

Question 16

In what position should you manipulate the hand at the midcarpal joints?

Answer 16

neutral with slight flexion and ulnar deviation

Question 17

In what position should you manipulate the trapeziometacarpal joint?

Answer 17

midway between flexion/extension and between abduction/adduction

Question 18

What is the closed pack position of the thumb?

Answer 18

full opposition

Question 19

What is the capsular pattern for the wrist?

Answer 19

limitations in flexion = ext

Question 20

What is the capsular pattern for the hip?

Answer 20

limited flexion/IR, some abduction

• (adduction/ER are fine)

Question 21

What is the capsular pattern for the knee?

Answer 21

flexion grossly limited, slight limit in ext

Question 22

What is the capsular pattern for the GH joint?

Answer 22

greatest limitation in ER, followed by abduction and IR

Question 23

What is the capsular pattern for the lower c-spine?

Answer 23

limited in all motions except flexion

- side-bending and rotation are equal, and worse than ext.

Question 24

What is the capsular pattern for the elbow?

Answer 24

loss of flexion more than ext

Question 25

What is the capsular pattern for the radioulnar joint, both proximal and distal?

Answer 25

limitations in pronation = supination

Question 26

What is the capsular pattern for the talocrural joint?

Answer 26

loss of PF more than DF

Question 27

What is the capsular pattern for the thoracic spine?

Answer 27

limitation of side bending and rotation GREATER than loss of extension GREATER than loss of flexion

aka:
sidebending/rotation > ext > flexion

Question 28

What is the capsular pattern for the lumbar spine?

Answer 28

marked and equal limitation of sidebending and rotation; loss of extension > flexion

Question 29

What muscle substitutions are common when hip extensors are weak?

Answer 29

lumbar extensors, adductor magnus, and quadratus lumborum

Question 30

T/F: Humeral head is anteverted 20-30deg.

Answer 30

false, it’s retroverted

hip joint is anteverted

Question 31

What is scaption angle?

Answer 31

30deg from frontal plane

Question 32

Why is the glenohumeral head most likely to be displaced inferiorly?

Answer 32

inferior capsule is least supported and most lax