Can you repeat the procedure to boost its claimed effect when its effect starts to wean off?
Do you have long term data in your prelim study (longer than a year)?
Clinical significance depends on: the impact of the condition on people's life, risk of procedure, cost, long term effect, the availability of alternative ect. The bottomline is: given what you know about the procedure (above), would people do it? This can be done with a questionare when you have the above info.