Hi there. These symptoms may be due to edema, in the tissue operated recently. Maybe new implant itself be impinging on the nerve roots. A repeat scan, mri should be asked for and assessed , compared with the preoperative one. Hope the neurosurgeon can solve these mysteries for you. Take care.
Sorry for the previous reply.
Hi there. The various causes of facial numbness on one side of the face are diabetes mellitus, peripheral nerve trauma, stroke, bells or lower motor neuron palsy, acoustic neuroma and trigeminal neuralgia. Consult a neurologist if there has been any such recent development in your husband. Dental consult is also warranted to rule out trigeminal nerve involvement or any dental cause of numbness. Take care.