My husband had s5-l1 spinal fusion 360 (minimal approach) performed 5 days ago. he is having severe upper thigh cramping in both of his legs. this was?

Seen commonly: muscle cramps can occur before or after fusion surgery. Sometimes the nerves which go to the muscles are still under duress and medication maybe necessary along with physical therapy. Let your doctor know as soon as possible that these scripts may be helpful.

Reassurance: As has been mentioned, this is most likely, a temporary post-operative phenomenon, which will fade rapidly over next few days. Discuss with surgeon and any other doctor involved. At some point, physical therapy, especially in pool setting, might alleviate most, if not all of this.