This is a risk of this surgery.
If you were not informed of the risks, then you need to consult a lawyer.
Stem cell therapy is not to the point of regenerating nerves.
You need an EMG/NCS, a test with electrodes, to see what exactly is wrong, as well as an MRI, post surgical.
You also need to see a physical medicine and rehabilitation doctor, who can arrange an exact post operative diagnosis.
OK, so that is an initial answer….
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