Here's an interesting article from Alon Marcus on the treatment of strains and sprains with Chinese medicine. It goes into great detail on the different types of sprains and strains but is oddly lacking when it comes to acupuncture treatment strategies. Perhaps these will be covered in part two?
Curiously, the only herbal formula he mentions includes a highly toxic substance, 蟾酥 Chan Su, or toad venom. He neglects to mention the two most famous formulas for the treatment of external injury, 跌打丸 Die Da Wan and 三黃散 San Huang San. Die Da Wan, or "hit-fall pill", can be taken orally directly after injury for 2-3 days. San Huang San, or the "three yellows powder" consists of Huang Qin, Huang Lian and Da Huang powdered and mixed together in equal amounts (one popular modification adds Pu Gong Ying, Shan Zhi Zi and Hong Hua). This powder can then be mixed with green tea, water or egg white and spread in a plaster on the affected area. For details on these formulas, take a look at Tom Bisio's A Tooth From the Tiger's Mouth.