M20.2Non-Billable (Header)Hallux rigidusChild CodesM20.20Hallux rigidus, unspecified footM20.21Hallux rigidus, right footM20.22Hallux rigidus, left footCode Hierarchy└M20Acquired deformities of fingers and toes└M20.2Hallux rigidus└M20.2Hallux rigidus