Who can make the decision to have adnoids removed?

Joint custody means that both parents have equal decision making on major decisions involving your minor children, covering health, educational and religious choices. This means you can’t go and decide to have the medical procedure done, over your ex spouse’s objection. Unless it  may be an emergency where both of you agreeing is literally threatening the life of your child. You don’t offer a reason as to what his objection might be. Did they consult with the ENT doctor or have you simply conveyed the information to your ex? Have them contact the doctor directly to find out why they feel the surgery is necessary. Have the doctor write a detailed letter why the medical procedure is necessary and provide a copy to your ex. If they continue to object, file a motion with the court to seek a court order to allow the procedure or alternatively, to terminate joint custody on medical decisions, so you are empowered with sole custody to make decisions involving your children.