Brief Answer:
The wound seems to be healing.

Detailed Answer:
Hello and welcome to " Ask a Doctor " service.

I have read your query and here is my advice.

I saw the picture of the wound you uploaded too.

In my opinion, the wound is closing from the depth and is localized in the skin, so, seems to be no reason to worry about spine infection.

In the other hand, the wound should be kept sterile with appropriate dressing.

Bactrim is the treatment of choice when it comes to stenotrophomonas maltophilla infection, so, you should continue the treatment as advised by your Doctor in order to prevent spreading of the infection in bones or respiratory tract.

Hope you found the answer helpful.

Let me know if I can assist you further.

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