| Inbound Relationships | Type | Active | Source | Characteristic | Refinability | Group | 
| Entire atlas vertebra | Is a | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Structure of transverse process of atlas | Is a | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Structure of arch of atlas | Is a | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Structure of tubercle of atlas | Is a | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Structure of articular facet of atlas | Is a | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Structure of foramen of atlas | Is a | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Structure of lateral mass of atlas | Is a | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Structure of fossa deferens of atlas | Is a | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Closed fracture atlas, comminuted | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture atlas, comminuted | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture atlas, comminuted | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed traumatic dislocation of first cervical vertebra | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture atlas | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture atlas | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Spinal fusion of atlas-axis for pseudoarthrosis | Procedure site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Arthrodesis by posterior technique of atlas-axis with internal fixation | Procedure site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 3 | 
| Spinal fusion of atlas-axis | Procedure site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Arthrodesis by anterior transoral technique, clivus-C1-C2, with bone graft and excision of odontoid process | Procedure site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Arthrodesis by anterior extraoral technique, clivus-C1-C2, with bone graft and excision of odontoid process | Procedure site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture of first cervical vertebra without spinal cord injury | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open dislocation of first cervical vertebra | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Open fracture of first cervical vertebra without spinal cord injury | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Arthrodesis by posterior technique of atlas-axis with bone graft | Procedure site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Platybasia | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Fracture of first cervical vertebra | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture of atlas without spinal cord lesion | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture of atlas without spinal cord lesion | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture atlas, comminuted | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Closed fracture atlas, isolated arch or articular process | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture atlas, isolated arch or articular process | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture atlas, comminuted | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Arthrodesis by posterior technique of atlas-axis with bone graft | Procedure site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Closed fracture atlas, comminuted | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Arthrodesis by posterior technique of atlas-axis with bone graft | Procedure site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Closed fracture atlas, comminuted | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture atlas, comminuted | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Arthrodesis by anterior transoral technique, clivus-C1-C2, with bone graft and excision of odontoid process | Procedure site - Indirect | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Arthrodesis by anterior extraoral technique, clivus-C1-C2, with bone graft and excision of odontoid process | Procedure site - Indirect | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Arthrodesis by posterior technique of atlas-axis with bone graft | Procedure site - Indirect | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Transoral fusion of atlantoaxial joint | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Posterior fusion of atlantoaxial joint | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Spinal fusion of atlas-axis for pseudoarthrosis | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Arthrodesis by posterior technique of atlas-axis with internal fixation | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Spinal fusion of atlas-axis | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Arthrodesis by posterior technique of atlas-axis with bone graft | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Fusion of atlantoaxial joint NEC | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture atlas, isolated arch or articular process | Finding site | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture atlas, comminuted | Finding site | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture of first cervical vertebra without spinal cord injury | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture atlas | Finding site | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture atlas | Finding site | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture of atlas without spinal cord lesion | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Open fracture of first cervical vertebra without spinal cord injury | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Fracture of first cervical vertebra | Finding site | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture atlas, comminuted | Finding site | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture of atlas without spinal cord lesion | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Closed fracture atlas, isolated arch or articular process | Finding site | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 1 | 
| Atlanto-occipital malformation | Finding site | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Unstable burst fracture of first cervical vertebra | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 3 | 
| Stable burst fracture of first cervical vertebra | Finding site | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 3 | 
| Entire bone of atlas | Is a | True | Bone structure of atlas | Inferred relationship | Existential restriction modifier |  | 
| Posterior fusion of atlantoaxial joint NEC | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Posterior fusion of atlantoaxial joint using transarticular screw | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 | 
| Posterior fusion of atlantoaxial joint using pedicle screw | Procedure site - Direct | False | Bone structure of atlas | Inferred relationship | Existential restriction modifier | 2 |