Brief Answer:
Read below.

Detailed Answer:
I read your question carefully and I am sorry about your symptoms.

It might have been useful if you had provided some more detail, things are usually more complex than what may seem. You should provide more details on what you mean by partial hand paralysis, which part of the hand, time and manner of onset, progression over time, accompanying symptoms such as numbness or tingling, other conditions you may have like diabetes etc.

With the only information being at this time that of a weakness involving some hand muscles I would say the most probable cause would be a peripheral nerve damage. Which nerve can't be said without knowing which parts are paralysed, what actions you are not able to perform, possible involvement of forearm etc, may be damage to the ulnar, median or radial nerve. Cause may be trauma like prolonged compression, metabolic conditions like diabetes, deformations from arthritis compressing the nerve etc.

As for treatment, first the cause must be determined through examination and tests like nerve conduction studies. Management depends from cause, nothing may be needed if due to trauma, treatment of conditions like diabetes, at times surgery when there is a compression, so it depends.

I remain at your disposal for further questions, but possibly providing more details.

---