Sydney Padua (of "The Thrilling Adventures of Lovelace & Babbage") offers tips for seeing pose and motion in cats - several teaching pages at the link.
Felinity - Cats & Their People
Canine and feline skeletal structures. Note the joints!
Diseño de Personajes
Muscles of the Cat Leg More
Cats Poses References by Eifi--Copper.deviantart.com on @deviantART
catdrawing_9-1_fur tips on how cats' whiskers should be depending on their fur length
Cat muscles dissection | anatomy corner, The muscles of the cat are similar to the muscles on a human. Description from anatomylist.com. I searched for this on bing.com/images
How to draw cats - anatomy by *Yolly-anda on deviantART
Sketching & Loving
Anatomy and drawing help