You could sue the driver who rear-ended you. Assuming that he or she is at fault--which is probably the case; the law presumes that, except in special circumstances, the rear driver is at fault in rear-end collision--he or she would potentially be liable for the degree to which the accident exacerbated, or worsened, your pre-exising condition or injury. To use an over-simplified example: say that if you did not have the pre-existing problem and the accident did all the damage, that your claim (medical care; lost  wages, if any; pain and suffering; and property damage) would be worth $40,000. If because you already had a pre-existing condition, the court concludes that half your injuries/costs are due to the worsening effect of the accident and half are from the pre-existing herniation, you could potentially recover half the $40,000, or $20,000. You should speak with a personal injury attorney to evaluate the strength of your claim and what it might be worth.