I understand no one here can interpret my MRI or x-ray. I'm trying to understand terminology. I think of subluxation as a term chiropractors use, but my lumbar flexion and extension x-ray mentions an 8 mm anterior subluxation of L4 on L5. I haven't seen this term used in previous x-rays or MRIs. Is this the same as slippage? And is spondylolisthesis the same same as anterolisthesis? Many thanks for any input.