Hard. Firm. Soft.
In order that doctors communicate clearly, we were taught early in our medical education how to use each of the above terms. I was reminded of that lesson when Heidi submitted a question that began, “Our cat has some hard object just below his knee…”

As much as we can do through the Internet, we still can’t feel or touch a remote object, person or pet, so I had to request an additional description and photo before I could go forward on this question.
“Hard” is defined as something with little or no “give.” Bone and metal qualify as hard.
“Firm” is the consistency of liver. Touch the surface of a liver and it can indent and allow an impression, but the impression isn’t permanent, the dent rebounds to the original shape. Even a heavily-scarred, cirrhotic liver will not approach “hard.”
“Soft” carries the implication of fluctuance. A lipoma, or benign fatty tumor, is soft. An abscess full of pus will feel soft before it ruptures and drains.
Proper use of these terms can help your pet’s doctor in evaluating your pet’s needs even prior to the examination.
What we see in the photo is almost assuredly a soft-tissue growth. If it is endowed with substantial fibrous tissue it may be “firm,” but, unless it is an outgrowth of bone it is probably not “hard.”
After Meowser has her visit to the doctor we will let you know what the final verdict is.
See you tomorrow, Dr. Randolph.