Can you suggest any herbal/holistic treatment for impact injured hand?

Many possibilities. It would help to know more about your injury. Homeopathic arnica is legendary for treating these types of injuries, both internally (12c or 30c potency) ; topically (see http://umm.Edu/health/medical/altmed/herb/arnica). Vitamin c ; zinc help injuries to heal. Acupuncture may help; microcurrent therapy ; cold lasers often help injuries to heal. Meriva (form of curumin) is a good anti-inflammatory.