the history so far u given may be because of scoliosis
spasms are due to :
Over-extending the muscles during physical activity
Improper lifting of heavy items
Low Potassium levels
Do check ur calcium level , low calcium can cause muscle spasm,
You should have ur xray spine and might required ct/mri
scan to diagnose the rt hand muscle \ spasm.
Suggested to visit neurospecialist after having ur calcium level report.