My Ageing Border Collie Has Recently Developed Pain In Her

My ageing border collie has recently developed pain in her back knee and we are told this may result from a tumour or an infection. I have been treating her with devil's claw, spirulina, wheat grass and dandelion root in the last few days. The vet is reluctant to do a biopsy or give her chemotherapy. Actually, she is improving. what do you think?
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