Biomechanics Flashcards
Most muscles in the body are what type of lever?
third class (bicep)
pivot —— effort up^ ———– load v———-
What is the convex-concave rule?
convex-concave movement = roll and slide are in OPPOSITE directions
What convex or concave rule applies to the spine?
convex rule applies at the atlanto occipital joint
- all else below second vertebrae follow concave rule
What is the concave rule?
concave on convex movement = roll and slide are in the SAME direction
What does a firm endfeel indicate?
capsular and ligamentous stretching
What does a boggy end feel indicate?
edema, joint swelling
What does a muscle spasm end feel feel like?
rubbery
What is the open-packed position for the GH joint?
55-70deg abd, 30 horizontal add, neutral rotation
In what position should you manipulate the SC joint?
arm resting by side
In what position should you manipulate the humerulnar joint?
70deg flex, 10deg sup
T/F: The closed pack position of the humeroradial joint is full extension and supination.
false, that’s closed pack for humeroulnar
- closed for humeroradial = 90deg flex, 5deg sup
What’s the closed pack position of the GH joint?
fully abducted/ERed
In what position should you manipulate the distal radioulnar joint?
10deg sup
In what position should you manipulate the knee?
25deg flexion
In what position should you manipulate the MCP joints?
first MCP: slight flexion
all others: slight flexion and ulnar deviation
In what position should you manipulate the hand at the midcarpal joints?
neutral with slight flexion and ulnar deviation
In what position should you manipulate the trapeziometacarpal joint?
midway between flexion/extension and between abduction/adduction
What is the closed pack position of the thumb?
full opposition
What is the capsular pattern for the wrist?
limitations in flexion = ext
What is the capsular pattern for the hip?
limited flexion/IR, some abduction
- (adduction/ER are fine)
What is the capsular pattern for the knee?
flexion grossly limited, slight limit in ext
What is the capsular pattern for the GH joint?
greatest limitation in ER, followed by abduction and IR
What is the capsular pattern for the lower c-spine?
limited in all motions except flexion
- side-bending and rotation are equal, and worse than ext.
What is the capsular pattern for the elbow?
loss of flexion more than ext
What is the capsular pattern for the radioulnar joint, both proximal and distal?
limitations in pronation = supination
What is the capsular pattern for the talocrural joint?
loss of PF more than DF
What is the capsular pattern for the thoracic spine?
limitation of side bending and rotation GREATER than loss of extension GREATER than loss of flexion
aka:
sidebending/rotation > ext > flexion
What is the capsular pattern for the lumbar spine?
marked and equal limitation of sidebending and rotation; loss of extension > flexion
What muscle substitutions are common when hip extensors are weak?
lumbar extensors, adductor magnus, and quadratus lumborum
T/F: Humeral head is anteverted 20-30deg.
false, it’s retroverted
hip joint is anteverted
What is scaption angle?
30deg from frontal plane
Why is the glenohumeral head most likely to be displaced inferiorly?
inferior capsule is least supported and most lax
