Your mother has suffered stroke (stopping blood circulation in an area of the brain due to its blockage from a clot), very likely due to a small clot arising from her heart (these clots have a tendency to be formed after valve replacement or ballooning surgery). This has resulted in weakness (paralysis) in the opposite limb.
The only definitive treatment available for this condition is to dissolve the clot within 3 hours from the onset of symptoms. Following that time window, the treatment remains essentially symptomatic with control of risk factors (to prevent future strokes) and vigorous physiotherapy.
In your mother's case, the risk of further clot forming in the heart and then getting detached into arteries of brain or other body parts has been decreased by giving a blood thinning drug called Acitrom. However, the dose of this drug needs to be monitored periodically as excess of it can cause bleeding from various body sites including within the brain and should therefore be monitored by doing a blood test called PT and INR.
Acupuncture is an effective Chinese System of controlling painful body complaints. Since you mention no pain, there is no indication for acupuncture in your case. Acupuncture will not have any effect on paralysis. The main thing to improve paralysis is physiotherapy and more physiotherapy.