Thanks for your query.
surgery carries little higher risk than lumbar spine
surgery .It is a well known complication that do occur in some cases post operative even in the best of hands & institution.Now she needs repeat MRI
to find the cause ,where there is wrong .what is the wrong. Solution can be there is proper investigation gives some clue towards the cause.
‘Hope I have answered your query, I will be available to answer your follow up queries, “Wish you Good Health and trouble free speedy recovery”