How many bones are in the feline "toe"?  Not counting carpals or
metacarpals, how many phalanges are there?  Is it the same as in our
hand, three phalanges per finger, and two per thumb?

Hi, thanks for the question.  

Cats have 14 phalanges in all, like humans. 

http://www.ivis.org/special_books/ortho/chapter_26/26mast.asp
"Digit I in the dog and cat has only two phalanges. The remaining
digits II to V have three: a proximal or first phalanx, a middle or
second phalanx, and a distal or third phalanx. The third phalanx
possesses an ungual process over which the nail grows."

Skeletal Illustration:
http://fp.dl.kent.edu/hyork/catfeet.htm


Additional Information:

Declawing is performed by removing the last phalange
http://familyfun.go.com/parenting/learn/activities/expert/petvetdeclawing/

"The actual cut is made between the last two phalanges."

Google Search Strategy:

cat or feline, phalanges

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Request for Answer Clarification by danb909-ga on 02 Jan 2005 19:22 PST

Hi,
    Thanks for a great answer.
    But what about the sesamoid bones?  What do they look like and how
many are there?  And how big?  Are they considered to be bones, and
would they not contribute to the overall bone count in the toe or paw?

---

Clarification of Answer by adiloren-ga on 05 Jan 2005 23:33 PST

Hi thanks for requesting clarification. I wasn't sure if I had
answered your question completely, as I only refered to the number of
phalanges and not the total bone count. I hope this helps.

There is one sesamoid bone in Digit I and 3 sesamoid bones in digits II through V.

These sesamoid bones are located at the metacarpophalangeal joints
(knuckles), which link the metacarpals with the phalanges.

In the feline toe (excluding the dew-claw) there are 3 phalanges and 3
sesamoid bones at the joints between the innermost phalanges and the
metacarpals.

http://encarta.msn.com/dictionary_1861719181/sesamoid.html
"ses·a·moid

noun  (plural ses·a·moids)
small roughly spherical bone: a small, roughly spherical bone lying
within a tendon to assist in its mechanical action or to bear
pressure"

http://www.vetinfo.com/dortho.html#Sesamoid%20fractures%20in%20Australian%20Shepherd
"The sesamoid bones are the small little bones that form the knuckles
and serve as pivot points for tendons as the run down the length of
the
metacarpal bones and toes."

http://www.ivis.org/special_books/ortho/chapter_26/26mast.asp
"The metacarpophalangeal joints are typical condylar joints,
possessing a medial and lateral collateral ligament and a synovial
joint capsule. These joints also possess two elongated palmar sesamoid
bones, and one small round dorsal sesamoid, dorsally over the joint.
Metacarpophalangeal joint I has only one sesamoid, which is palmar. "

Three-Dimensional Model of the Feline Hindlimb
doi.wiley.com/10.1002/jmor.10233

Overview of the region:

http://www.ivis.org/special_books/ortho/chapter_26/26mast.asp
"The dog and cat have five metacarpal bones. Metacarpal bones II and V
are relatively similar in size, and metacarpal bones III and IV are
similar in size, although longer than II and V. Metacarpal I is much
smaller than bones II and V. The four major metacarpals are arranged
with a caudal convexity that probably allows the upper paw to absorb
the shock of foot strike.
 
The metacarpophalangeal joints are typical condylar joints, possessing
a medial and lateral collateral ligament and a synovial joint capsule.
These joints also possess two elongated palmar sesamoid bones, and one
small round dorsal sesamoid, dorsally over the joint.
Metacarpophalangeal joint I has only one sesamoid, which is palmar.
 
The proximal interphalangeal joints and the distal interphalangeal
joints are also condylar joints. Each has a medial and lateral
collateral ligament and a synovial joint capsule. There are no
sesamoids around these joints.
 
Digit I in the dog and cat has only two phalanges. The remaining
digits II to V have three: a proximal or first phalanx, a middle or
second phalanx, and a distal or third phalanx. The third phalanx
possesses an ungual process over which the nail grows."


Humans:

http://www.uq.edu.au/~anvkippe/gmc/musccomp.html
"Skeleton of foot = 7 tarsal bones + 5 metatarsals + 14 phalanges +
inconstant number of sesamoid bones (including two under head of first
metatarsal)"

http://www.uq.edu.au/~anvkippe/gmc/musccomp.html
"Skeleton of hand = 8 carpal bones + 5 metacarpals + 14 phalanges +
inconstant number of sesamoid bones"