Not necessarily. Amusement parks often use waivers, ticket-back language, and signs disclaiming responsibility, and they will point to them to discourage a claim. But these are not the ironclad shield parks want you to think, and their reach and enforceability have real limits.
A waiver generally cannot excuse a park's own gross negligence, so where your injury came from poor maintenance, operator error, or the park's careless conduct, the waiver may not apply. And a claim against the manufacturer of a defective ride is separate from the park's waiver entirely.
The key question is usually not whether you signed or accepted a waiver, but what caused your injury. Because these terms do not always control, it is worth having them and your situation reviewed before concluding you have no claim.