Check the edges of the wound. Is it still raw, and healing? Or is it old scar tissue?
If it is still healing you can try to line up the edges and...(I know how bad this sounds) Supper glue the raw edges together. If the tear has healed in an open position it will not grow back together without reopening the wound, and making it bleed. If this is the case see how it adapts to the injury before you try to fix it, or take it to the vet for pain meds first.
My vet turned me onto Supper glue. Best Damn bandaid I ever used. It is sterile, non-toxic, water proof, a hell of alot stronger then a little plastic strip, and it doesn't require stitching an allready injured and stressed animal. I have used it on tears in the foot webbing, mouth injuries, and bites from other gators. It is a great cover for nose rub also. It will loosen and peel away at about the same rate the skin heals.
It works on people too. I have started keeping a tube in my own firstaid kit.
The only warning is that you need to stop the blood flow before you try to close a wound. If you glue over a seeping wound it can pressure up and tear the wound open agian. Because of the strength of the glue it will often tear next to the orgininal injury. Leaving you with two wounds. Pockets of blood under the skin can increase chances of infection, and tissue damage.
I hope this helps someone. A $2.00 tube of glue has saved me a few hundred in vet bills allready.