What is the best treatment for fixed abnormal limb posturing?

Treat posturing. Passive range of motion administered by a physical therapist, serial casting to increase range of motion. Medications such as dantrium, (dantrolene) Baclofen or members of the valium family can help. Injections of Botox may help to improve range of motion. Speak to a physiatrist, a doctor specializing in physical medicine and rehabilitation.