Brief Answer:
Pseudoarthrosis means fracture is not United

Detailed Answer:
Hello, I have studied your case. Pseudoarthrosis means when bone fusion is not achieved. Whenever back surgery is done doctors try to fuse bones in between using bone graft and screws. When fusion achieved it causes pain relief. But if fusion is not achieved then pain continues, it is called Pseudoarthrosis. It will need removal of all fibrosis tissue and a repeat bone graft. Some time screws may also need to be revised.
As far as coldness in one leg is concerned it is mostly due to nerve compression during surgery. Some time it can an be due to nerve stretching. It will improve with time.
I hope this answer will be useful for you. Let me know if you want to ask any other follow up questions.
Thanks

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