As physiotherapists, we are trained to detect RED FLAGS (i.e.: lesions to central nervous system, spinal cord lesions, cauda equina lesions, tumors, etc). Red flags are basically signs that there might be something non-mechanical that might be the root cause of pain. By ruling out systemic causes, we can ensure that we are indeed working on mechanical problems that physiotherapists can resolve most times. Those who presents with RED FLAGS or are non-responders would be referred back to MD for further investigation or to other healthcare provider.
It is common for physiotherapists to refer clients for acupuncture, osteopathy, massage, pool therapy whenever appropriate. Different disciplines can target the same problem but at a different angle and sometimes tissues just need to be stimulated in another way.