knee bone vs patella

[cmungall]

knee bone has only one subtype

.......po MA:0000670 ! leg bone ........is_a MA:0000666 ! knee bone *** .........is_a MA:0001374 ! patella

are there other kinds? Should these be merged?

Original comment by: cmungall

Original Ticket: obo/mouse-anatomy-requests/53

[cmungall]

• assigned_to: nobody --> hayamizu

Original comment by: tfhayamizu

[cmungall]

"are there other kinds?" -- possibly

I have found evidence for a "fabella" (http://en.wikipedia.org/wiki/Fabella) in the mouse (in "Micro-Tomographic Atlas of the Mouse Skeleton" by Itai Bab; see attached file), which might be considered to be part of the posterior region of the knee.

Given the minimal evidence, I have not yet added "fabella" as a term. It is on my list of things to investigate further.

Evidently, in humans the fabella is a normal variant (i.e. present in "10% to 30% of individuals"). I don't know anything about it's incidence/prevalence in mice. My guess is that this has never been investigated.

"Should these be merged?"

I feel that it is appropriate to keep "knee bone" and "patella" as separate concepts.

Original comment by: tfhayamizu

[cmungall]

from "Micro-Tomographic Atlas of the Mouse Skeleton"

Original comment by: tfhayamizu

[cmungall]

Actually, the MA already has "fabella" as a synonym for MA:0001378 "sesamoid bone of gastrocnemius." It is currently a subclass of both "sesamoid bone" and "lower leg bone." As I know you realize, joint regions are difficult to deal with. The gastrocnemius muscle originates from condyles of the femur, crosses the knee, and inserts into the calcaneus. Thus, the actual position of the fabella appears to be within the posterior part of the knee region.

Original comment by: tfhayamizu

[cmungall]

• status: open --> closed

Original comment by: tfhayamizu