which Chinese herb help this problem ?
Many of the Chinese herbal formulas may be appropriate to help slow the progression of spinal stenosis and deal with associated pain issues. Personally, I find acupuncture crucial in the overall treatment of stenosis with Chinese Medicine. Which formula you would use would depend greatly on the overall underlying diagnosis from a Chinese Medicine perspective (see “What Does Acupuncture Treat?” for more on treating causes and not conditions as is often the case with western medicine).
Stenosis can have an autoimmune’esque component to it which may be driven by kidney yin deficiency - so a formula such as liu wei di huang wan alone or as a base may be appropriate. Another possibility is strong qi and blood deficiency and a tonic formula as a base or alone such as bu zhong yi qi wan may be appropriate.
Generally in addition to treating the root weaknesses you want some qi and blood movement to help with the more pressing issues of pain. But you have to very careful to not create too much movement, particularly in people with stronger deficiencies (weakness) or with yin defiiciency as the warming herbs that create the movement may make matters worse.
The only way to know the appropriate formula is to see a practitioner and get a diagnosis in Chinese Medicine terms. Your practitioner will then know which formulas may be appropriate.