I know that in Canada, the training and certification for teachers varies by province, so even within our country you have teachers with different levels of training and exposure. That being said, the literature indicates that training is lacking for how to work with children with varied levels of disabilities. Teachers tend to have more experience with cognitive and learning-based disabilities that will impact their Individualized Education Plans (IEPs) and therefore the accommodations and/or modifications that they are allowed in the classroom. Teachers tend to have less experience in working with or accommodating children with different physical or behavioural disabilities.
My work is with children with acquired brain injury (ABI) and teachers tend to have little to no knowledge of how to work with such children, accommodate their evolving and ongoing needs, and have them work within the existing classroom setting. There is a real need for further education and formal training for teachers regarding children with various types of disabilities.
I agree... Lately, in Portugal some post.graduated courses allow teachers to improve their learning and performance but it's highly probable that, when they face a child in their classrooms they have never had any contact with the reality (even during their formation) before.