Lower back pain

[nmarman]

physiofi is right about most parts of your condition.

Giving way is a sign of knee or hip instability but can also be a sign of back instability with scoliosis.

With your traumatic history and age you are a good candidate for X-ray.

A long story short you are not getting any better and no one knows why, any good practitioner would be asking for extra imaging to either confirm or rule out other diagnosis. Ask your GP for X-ray of the Lumbopelvic and Thoracic spine stating that both acupuncture and physio have offered only limited relief. alternative ask you chiropractor to take the x-rays as chiropractors are trained in musculoskeletal radiology, they should have equipment on site.

Other wise is sounds like you might have had a disc lesion in lumbar region possibly central disc bulge. This would have lead to instability making it hard to recover from treatment alone. to define this a MRI would be the best possible examination.

A history of desk bound occupation or multiple children - would decrease you abdominal/ core strengths making you a slow recovering patient. given the giving way it is apparent that the muscles are failing to provide stability at the moment purchase a good strap, let pain disparate and stop the pain cycle then exercise in water until you feel confident again.

GET EXTRA IMAGING!!