hi, thank-you for providing the brief history of you. A thorough neuromuscular assessment is advised. As you are suffering with Back ache and now the pain is in the lateral side of the leg, I suspect it to be a pinched nerve in the lumbar spine, as this is the classical symptom of lumbar radiculopathy in your history. Also, undergoing physical therapy should help you , as in my clinical practice I see cases with similar complaints and majority of them respond well to physical therapy. The physical therapist may use - Therapeutic ultrasound therapy and TENS therapy in initial stages to reduce pain and inflammation. Later stages exercises will be taught to improve the muscle strength in the lumbar spine, core, pelvic floor etc. Regards Jay Indravadan Patel