Hi, thanks for asking from HCM. I can understand your concern. You have already fused spine at L5 S1 level. Fusion of spine increases chances of disc herniation one level above and below. It has happened in your case. You are having disc bulge at L4-5 level. But good thing is, it is only bulge and thecal (spinal nerve covering membrane) compression. There is no actual nerve compression of L5 or traversing nerve roots. I am worried about your S1 nerve root. As your spine is fused at this level, it should not be compromised. You should consult your operating spine surgeon and get a NCCT lumbosacral spine to rule out spinal canal stenosis, graft migration. Get a nerve conduction velocity and electromyography of L4 to S4 nerves to rule out nerve damage and muscles affected. It will also confirm the degree of damage and affect of disc bulge. Till then, for relief in your symptoms - You should avoid forward bending, weight lifting. - Avoid prolonged standing or sitting. - You can take painkiller like pregabaline, gabapentine or combination of gabapentin+amitriptyline/nortriptyline, after proper prescription. - For leg spasm, do stretching exercise, apply hot fomentation over back and pain area. - Apply diclofenac gel locally over pain site, after prescription. - Take nerve regenerating supplements like S-adensoylmethionine, B12, folic acid, Pyridoxine, Pantothenic acid after proper prescription. If you can send me your MRI pictures and treatment summary, I can help you more. Hope above answer will help you. Thanks. Take care. Dr Ishu Bishnoi