Thank you for your question to HCM.
Leg pain and weakness can stem from pressure or intrinsic pathology of the nerve
. To find out the cause and location of your problem I would recommend getting Electromyography
and Nerve Conduction testing (EMG/NCV) of left leg. For my patients I would also get MRI
of the lumbar spine
because lumbar disc herniation is a common pathology that causes leg pain and weakness. Rarely thoracic disc herniations (midback) can lead to such symptoms and MRI of the thoracic spine would be the next step if no correlating picture is found in lumbar spine.
Hope this is helpful. I will be happy to answer any questions you may have.