| Inbound Relationships | Type | Active | Source | Characteristic | Refinability | Group | 
| Sacral epidural steroid injection | Procedure site | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Therapeutic sacral epidural injection | Procedure site | False | Sacral extradural space | Inferred relationship | Some | 3 | 
| Local anesthetic sacral epidural block | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Sacral epidural neurolysis | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 3 | 
| Epidural injection of anesthetic substance, diagnostic, caudal, continuous | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 1 | 
| Sacral epidural steroid injection | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 1 | 
| Injection into sacral epidural space | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Epidural injection of contrast substance, caudal | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Epidural injection of neurolytic solution, caudal | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 3 | 
| Epidural injection of anesthetic substance, therapeutic, caudal, continuous | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 2 | 
| Therapeutic sacral epidural injection | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Epidural injection of anesthetic substance, therapeutic, caudal, continuous | Procedure site - Direct (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Sacral epidural injection using computed tomography guidance (procedure) | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 2 | 
| Epidural injection of contrast substance, caudal | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 1 | 
| Epidural injection of sacral spine using fluoroscopic guidance (procedure) | Procedure site - Direct (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Therapeutic sacral epidural injection | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Sacral epidural injection using computed tomography guidance (procedure) | Procedure site - Direct (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Epidural injection of sacral spine using fluoroscopic guidance (procedure) | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 2 | 
| Injection into sacral epidural space | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 1 | 
| Sacral epidural injection using computed tomography guidance (procedure) | Procedure site - Direct (attribute) | True | Sacral extradural space | Inferred relationship | Some | 1 | 
| Sacral epidural injection using computed tomography guidance (procedure) | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 2 | 
| Epidural injection of sacral spine using fluoroscopic guidance (procedure) | Procedure site - Direct (attribute) | True | Sacral extradural space | Inferred relationship | Some | 1 | 
| Epidural injection of sacral spine using fluoroscopic guidance (procedure) | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 2 | 
| Therapeutic sacral epidural injection | Procedure site - Indirect (attribute) | False | Sacral extradural space | Inferred relationship | Some | 1 | 
| Local anesthetic sacral epidural block | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 1 | 
| Epidural injection of anesthetic substance, therapeutic, caudal, continuous | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 3 | 
| Entire sacral extradural space (body structure) | Is a | True | Sacral extradural space | Inferred relationship | Some |  | 
| Therapeutic sacral epidural injection | Procedure site - Indirect (attribute) | True | Sacral extradural space | Inferred relationship | Some | 2 |