One of my cats Limped for ages there was no fighting marks, scabs or nothing that you coulds see she was put on a high doses of metacam, the drug never touched her either, after six weeks or so after alot of different meds then x rays that cost quite alot of money they then put her on antibiotics costing around £9.00, If only they had done this first instead of going down the expensive root it would have saved me around £350.00, They said it must have been a deep muscle infection,