Scapula and Levers

part 1 of trap forms a _ lever because??

Lower fibers form a _ lever because??

We only have levers in what motions of scapula?

Upward and downward rotation

Where is motive force?

Where muscle attaches to scapula (bone that moves)

Where is RF?

Humerus hanging

Part 1 of trap lever parts and type

Rf= humerus

MF= where muscle attaches to bone that’s moving (where it attaches to scap)

Rod= scapula

Axis Varies but in this case it’s inside scap.

So, it goes Down RF, Up MF, axis.

Type 3 lever

Lower fibers

Both MF and RF going down with axis in middle = type 1, ROM advantage because MF arm is short

MA system of trap?

Upper fibers

ROM system of trap?

Lower fibers

What’s required for a MA system to have greater ROM capacity?

Longer fibers

What’s required for an ROM system with short fibers?

Larger cross section