Lecture 12 - Metacarpals and Metatarsals Flashcards
how many metacarpals do we have
10
characteristics of MC1
THUMB
- > shortest MC
- > broad and robust
- > proximal articular surface is saddle shaped (articulates with trapezium)
characteristics of MC2
- > normally the longest MC
- > proximal end resembles distal femur
characteristics of MC3
- > sharp projection at proximal end - styloid process
- > proximal end resembles distal tibia
characteristics of MC4
- > shorter and more gracile than MC2 and MC3
- > has a more square base
characteristics of MC5
- > thinnest and shortest
- > no facet on medial side (nothing to articulate with)
how can distinguish between the different metacarpals?
look at the proximal ends of the metacarpals
- > MC1 is saddle shaped
- > MC2 is similar to distal femur (2 condyle like shapes)
- > MC3 has styloid process, looks like distal tib/medial malleolus
phalanx vs phalanges
phalanx (1) phalanges (2)
what are the different hand phalanges and list their characteristics
Distal
- > finger tips, longer than toe tips
Intermediate
- > two part base where they articulate with proximal phalanges
Proximal
- > base is oval shape
- > uniform shape from proximal to distal end
describe the differences between metacarpals vs metatarsals
MC
- > short and thick
- > uniform size frm proximal to distal end
- > round distal end
MT
- > long and thin
- > tapered from proximal to distal end
- > squished distal end
Characteristics of MT1
- > shortest MT
- > broad and massive
characteristics of MT2
- > longest and narrowest MT
- > slight styloid process on base
- > eggplant shape base
- > medial facet to 1st cuneiform
characteristics of MT#3
- > very similar to MT2
- > base is more square
- > tubercle distal to lateral articulation surface
- > pizza shape base
characteristics of MT4
- > shorter than MT2 and MT3
- > square shape base
characteristics of MT5
- > large styloid process
- > distinctive and blunt for muscle attachements
