What is a muscle knot?

Knot neard dog's hip. Thought was hurt muscle. Not sore anymore but knot is still there what could it be?

• We left my dog alone with another dog. They like to play rough. We came back our dog had a hard time jumping on the couch and didn't want to walk. We found a knot slightly above his hip. It hurt him for us to touch it. We thought he got injured and pullled a muscle or soemthing. This was Sunday. By Tuesday it wasn't hurting him anymore, but the knot is still there and is the same size. I am taking him to the vet today, but wanted to see if anyone on here as ever seen such.

• Answer:

  Yes, It is possible that the dog has a hematoma or seroma. These things are caused by trauma and are a build up of blood or serum under the skin. Your vet will probably do an aspirate of it (stick a needle in it and try to pull out fluid). Many times these things go away on their own, but your vet might put the dog on antibiotics to be safe. I hope that your vet appointment goes well and that it is truly something little like this.