Neurologically Incontinent Cat

Our 5 year old male cat was hit by a car 5 days ago. He has a broken tail near the base, broken pelvis, and a couple of broken ribs. Missing a patch of fur on one side, but no other visible external injuries. He does have movement in his back legs but is not trying to move around yet. After x-rays and some debate, vets decided not to operate, either on the pelvis or to remove his tail. The tail does not seem to cause him pain, so they want to wait and see. Because of the tail fracture, he is incontinent, as to both bladder and bowel, so I will have to express for him 4x day. He is a great cat and I want to give him every chance to recover – he is scheduled to begin acupuncture treatments in 2 weeks. He is coming home today to be on cage rest for 6 weeks or so. Do you have any herbal/homeopathic suggestions that I can include in his recovery?

Making sure he has access to a diet high in bioavailable nutrients would be the first thing on my list. Please see the work of Richard Pitcairn, "Natural Health for Dogs and Cats", "The Complete Herbal Handbook for the Dog and Cat" by Juliette de Bairacli Levy and "The Barf Diet" by Ian Billinghurst for further information and recipes. If possible, do add beneficial oils to his diet such as salmon oil and/or Triple fish oil (mackerel, sardine and anchovy) as these are often indicated in nervous system function.
Assuming he is not on any other medications, nerve tonics such as St. John's Wort (Hypericum perforatum), Oatstraw (Avena sativa), Ginkgo (Ginkgo biloba), Skullcap (Scutellaria laterifolia), Gotu Kola (Hydrocotyl asiatica) and Nettle (Urtica dioica) may help. You could also look at using the Bach flower essence, Rescue Remedy: dilute four drops in 50 ml spring water and put one dropperful of the diluted essence in his food twice a day.
Homeopathics like Arnica montana 30C and Hypericum perforatum 30C may also be of use.
The healing of nerve tissue takes a very long time but, with patience, you should see quite an improvement.