Thank you so much! I'm not sure which leg you're pointing out but I know how bad they all look so it doesn't matter. xP (If it's the front one, then I agree; I realized that it looked like she had broken a bone or something as I drew it, but it looks just as funky as all of the other legs. [shrugs]) I bookmarked the page for reference, it's helpful already. I'll have to go Google "deer anatomy" and their "deer bone structure" and study it. [nuzzles] I admire your art very much, I'll study that too! xD

|D LOL yeah I've had some past experiences drawing terrible horses; I guess that's where I got my bad anatomy. Actually I have some oldish pixel horses I drew sitting around my computer...I guess I can see what was wrong with those and improve from there. But thank you a millions! Your artwork is absolutely amazing and you know it, so getting tips from you is a big help, as is with 21.

[goes to study] <3

I'm not an authority on deer anatomy - but I'm pretty familiar with equine anatomy, so I guess I have "authority by association." 8D And I love giving AND recieving constructive criticism. ^.^ So here's my attempt at a scholarly little analysis of the piece.

I'll start with proportions.
Wonkiness is always an issue. Keeping "pieces" in proportion is a pain in the arse - it's difficult, involves bookoo ratios, and is just... Hard. The body and left hind leg (the hind leg that's touching the ground) are in VERY good proportion from what I can tell. It just "looks right" - which is generally how I tell if something I drew is in proportion: if it looks natural. We're technically animals, and as such our brains have a way of discerning what looks right - even babies do it. Training yourself to see it right off is hard though. I still have to take a few days away from a piece then whack at it again to make sure I've got proportions right.
Anyway, the length of all the legs is pretty spot-on.
The head/neck area is a little funky. xD Part of that is the pose, in such case the neck is pretty right on. The deer's head though, should probably be a bit bigger.

Now a bit of leg anatomy. xD
The left hind leg is AWESOME. Very, very good. Proportions of bones, angles, etc - greatness. The only thing with it is that the knee joint (what you might think of as the thigh) probably could have been up just a tad higher. On the right hind leg (background), yes, it is bent awkwardly. I think what happened was a bit of a mis-count in the number of joints. I do that a lot (a mistake that involves a lot of cursing and erasing to correct). Just try to remember that all mammals have the same basica anatomical structure as humans. Hip socket, knee, ankle, and first-toe are the primary joints exhibited by quadrupedal mammals (and pretty much all mammals in general). The hip socket is obvious, and you don't really see it - it lies essentially dead-center over the circle of the buttocks (think of the circles you likely draw in the sketch before you really get into the drawing - one for the chest cavity, one for the buttocks, one for the head, etc). The knee joint is the first bend, and usually sits right over where you see the underbelly disappear. The ankle is always high. Thus, the majority of most mammals' legs is comparable to the foot of humans. The last joint is comparable to the first knucle on your toes - which, on a deer, is the part where all the little fluffs of fur are before the hooves.
Anywhoot - back to that leg. The bend you're showing shouldn't have come until further down the leg, essentially. It's really hard for me to say how to "fix" it or how it "should" look in text. xD
Front legs now. Firstly, the overall position of the forelegs is a little too high. The elbow usually lines up with the bottom line of the chest cavity just like the knee joint lines up with the underbelly. Also, it might help to remember that you can usually see some "evidence" of the shoulder up high on the back - a "lump" of muscle and bone. Quadrupeds generally have big shoulder blades. From there on, it seems to be another mis-reading of joints and how they work.

Here's some links - one to a labelled horse skeleton, one to a nicely rendered deer skeleton, that might be of some help!!
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I hope I don't seem snobbish. Most of the things I tell people are often the same things I have to work on! I just have a better seeing eye than I have a drawing hand, to be honest. But I've been told I did a fair job on leg anatomy in the following unfinished sketch of my deer Draco; it's clean and simple lines, so it may help. ^.^
Draco

Much love, hugs, happy wishes, and all that good artzy stuffins!
~ Draco