**Pain Assessment in Children Undergoing Spine Surgery** This research is about studying pain in kids and teens who are getting spine surgery. We want to understand how children, especially those who can't talk well, feel pain after surgery. This helps doctors give better care. **Who can join?** We're looking for kids and teens aged 10 to 21 years old who are going to have spine surgery. They need to be able to understand and answer questions. Kids with no big past surgeries are okay. They can be any gender or from any ethnic background. **Who can't join?** Kids who can't speak English or French, have developmental delays like autism, or have serious health problems can't be part of this study. **Study Details:** - **Length of Study:** We will observe participants during their surgery and recovery. - **Visits Needed:** Participants will be part of several assessments and visits around the time of surgery. - **Purpose:** To learn about pain in children who have limited ability to communicate and improve their pain management. If you're interested, please consider if you meet the criteria and can commit to the visits.