Answered by: James L. Cook, DVM, PhD, DACVS, DACVSMR:
This is really difficult to provide a general answer to, as it really is such a multifactorial decision that should be made on a case-by-case basis considering patient and client factors and goals. To be very general, surgery should be considered if there is a “mechanical” problem (e.g. fragment, instability, tear, etc) that can be safely and effectively treated surgically, for developmental problems (e.g. hip dysplasia, elbow dysplasia, etc) that have a proven surgical treatment that beneficially improves long term outcomes, or for advanced, symptomatic arthritis when medical treatments are not working well and a good surgical procedure is available.