A GP is basically a sorting office, they decipher what they think is wrong with you then send you off to someone they think may help.
The problem comes when there really isn't someone beyond the GP that can help in any substantial manner.
There is a reason for this, modern medicine decided (or those that run it) that we are better off pursuing a drug based road to medical treatment and the many things that fall outside of drug based treatments considered "Alternative".
So say you have a condition that can't be treated with drugs, well that rules out vast areas of modern medicine to start with, physio won't help? Sorry we can't help you - you're left to your own devices.
This is actually more prevalent than you think.
I'm going to go off at a tangent here but there is a point to all this.
My wife has Multiple Sclerosis (MS). Modern medicine has no idea what MS is. The current theory is that it's an autoimmune problem, but after 160 years trying to either establish this or even work out any reasons for the etiology of MS being linked to the autoimmune theory, they still draw a blank. So for medical purposes "MS" is a general heading for people that have displayed two or more symptoms that fall into the category of "MS" separately but within a a specific time frame.
Current treatment for the best guess idea of this condition is to throw lots of drugs at people with MS, mostly classed under the heading of Disease Modifying Drugs (DMD's). As the name suggests, they aren't designed to cure the cause, but treat the symptoms, which they don't understand. On the whole these drugs cost a fortune, and two years ago they were considered a massive waste of money. Read here:-
Error
So unless my wife wants to take Drugs that the manufacturers don't understand what they do, for a condition they don't understand, then there is nothing they can do to help. You slowly progress until eventually you die of complications. Sorry, bye bye.
Well that won't do, so we do our own research which bizarrely lead us to a dental specialist (very very long story). Ultimately the following article pricked up our interest so off we went to Putney to see the chap.
How a dental brace could cure MS, migraines and paralysis - Health & Beauty - Life & Style - London Evening Standard
It turns out my wife has an underdeveloped jaw which is giving her TMJ issues and a lot of pain and making eating difficult. So she had some treatment start a little over a year ago and slowly, symptoms associated with MS are being removed and it is transforming her life. It turns out she has a skeletal misalignment issue which is causing all sorts of problems with her entire body. This isn't some new fangled medical theory, you can trace it back 2000 years plus to the Chinese who look at the body as a machine that needs to work in perfect harmony. One bit if it being damaged/wrong can cause all sorts of issues.
I documented her treatment here (I post as EJC):-
AtlasBalance (jaw misalignment) Treatment - EJC : Chronic Cerebrospinal Venous Insufficiency (CCSVI)
You'd think this would be well received or people would be queuing up to study it, well patients are queuing up to See this guy, but the powers that be are simply not interested. There's no drug to sell, no back end, no funding for studies because you can't earn anything out of it by curing people without drugs. There are certain people actually trying to discredit the guy because he is so outspoken about how little the NHS do for this awful medical condition.
If you have back problems, jaw problems, migraines all sorts, have a chat with this guy he's a breath of fresh air in this drug fueled world that we live in. His contact details are at the bottom of the Standard article linked to above.