 So I just want to share some insights we got from our own data. So I think it was quite complete what you said, so you can decide if you take an interbody graft, if you don't take an anterior plate or no anterior plate. We generally use the PKH, and I will present some data of our own department on anterior plate with our versus PKH standalone. And of course you may have the ideal case that a patient with a case standalone has a perfect fusion without loss of the correction and it looks quite fine. After two years you see a fusion. This is what we see in a lot of cases. Now in general if we have some spondylosis we put in the spondylosis material, the bone, and this is the PKH kind of for artificial polymer and it's just visible with this small titanium part so that you can just see where it is exactly placed. We only put in there the ventral osteophytes. So and this is, it's a quite straightforward procedure, you know it, and it's a short abrasive time and everybody is fine, but it's funny when we changed about 10, 12 years ago from anterior plate to PKH standalone we were quite happy, but our nurses said it's worse. They said the patients complain about neck pain and stuff, and we said no, everybody does it, it's good, but they were right. And this is a patient's way, what we see also, that patients had a quite normal post-operative course in the beginning, then there was some subsidence after six weeks, we all see the patients after four to six weeks, and he had a persistent pain in the neck, sometimes even radiating to the arm, and on MRI and bone scintography we thought it was pseudotrosis. And I think that standalone cage, now we know that post-operatives you have a higher range of motion than in the healthy spine. So you can prevent it with using a collar, but there's a significant risk of subsidence. Some say subsidence is necessary to reach a fusion, but there had been at that time no prospective studies where in the literature so we decided to look in our own patient collective, and it was already mentioned there are two problems with subsidence, that is that you may have a loss of the low doses, which you might have re-established with the surgery in the first part, and there's a loss of this kind which may result to re-stinosis of a foramen with arm pain, or even with a sensorimotor deficit, and it may be just neck pain. There are two factors. One is that what is found in biomechanical studies that the range of motion is higher because you don't have the anterior ligament. And the second thing is, of course, especially in Germany we have elderly population, there may be a reason that we see more cases of subsidence. And over three years we've made a collection of data prospective of about 180-190 patients, and with the first patients we treat them only with a standalone peak age and the consecutive patients of about 95, we made it with a peak age plus anterior plate. And what did we see? So after the follow-up rate was quite good, 90 and 87 percent, and we saw a subsidence with Cages standalone in over 60 percent. But this is like in a lot of other studies, but even an anterior plate, because it's a kind of dynamic fixation, there may be subsidence. The difference was that the subsidence in standalone peak age was much higher than in the anterior plate fixation, that patients really on the neck disability score and all these measurement tools, they complained more about neck pain. The number of redo surgery because of side atrociousness and for arm pain and all these things was much higher in the standalone peak age group. While we thought it would be different, the adjacent segment disease was not, there was no significant difference. So anterior plate fixation did not lead to a much higher number of adjacent segment disease. And that's what you already mentioned that with the resection of the anterior ligament, you lose the biomedical tension on the ventral surface and that's what the anterior plate works fine with. If you do anterior plate fixation, it takes more OR time. It's maybe a matter of cost, but I heard that the implants with the local companies or the prices are quite affordable. So that might be not a reason and there was no significant difference in the infection, the risk of myelopathy, horn syndrome or a section of the recurrent laryngeal nerve because you need a bit more space if you do anterior plate fixation. And so we concluded from our own data in this kind of population that with the plate fixation it reduces especially the rate of painful subsidence. You have less patients where you have to do a redo surgery and especially it's not only a radiological improvement which may be not a good outcome measurement but it's really that the patients are doing better and they don't have to use their cervical collar. They go off but they don't receive any physiotherapy or stuff like that for the first four to six weeks so they can't do anything like this. And what we have to take into account is that it's a prolonged time of surgery and higher costs. That's just additional.