Patterns in Treatment Practice of Non-displaced Type II Odontoid Fractures

Wednesday, February 21, 2024

Presenting Author(s)

SG

Sennay Ghenbot, MD (he/him/his)

Resident Physician
Walter Reed National Military Medical Center

Co-Author(s)

DF

Donald Fredericks Jr., MD

Staff Surgeon
Walter Reed National Military Medical Center, United States
MH

Melvin Helgeson, MD

Staff Surgeon
Walter Reed National Military Medical Center, United States
CM

Conor McCarthy, MD

Resident Physician
Walter Reed National Military Medical Center, United States
MO

Matthew O'Hara, MD

Staff Surgeon
Walter Reed National Military Medical Center, United States
AP

Alfred Pisano, MD

Staff Surgeon
Walter Reed National Military Medical Center, United States
CS

Cody Schlaff, MD

Resident Physician
Walter Reed National Military Medical Center
Bethesda, Maryland, United States
JT

Jeremy Tran, MD

Resident Physician
Walter Reed National Military Medical Center, United States
SW

Scott Wagner, MD

Staff Surgeon
Walter Reed National Military Medical Center, United States

Introduction: Odontoid fractures represent approximately 1/3 of all cervical spine fractures, typically resulting from high energy mechanisms in the young and low energy mechanisms in the elderly. Type I and III odontoid fractures are typically treated non-operatively with aspen collar immobilization. Treatment of type II odontoid process fractures are of particular interest because of the risk of nonunion, which is thought to be secondary to watershed blood supply to the base of the odontoid process. Though there is consistent agreement regarding management of displaced type II fractures, there is marked heterogeneity in the clinical management of non-displaced type II fractures. The purpose of this study is to investigate overall patterns of surgical treatment of non-displaced type II odontoid fractures.

Methods: We queried the Military Health System Data Repository, consisting of medical treatment data of all active duty service-members, dependents, and retired beneficiaries, for the international classification of diseases, 10th revision (ICD-10) codes for non-displaced type II odontoid fractures and current procedural terminology (CPT) codes for their surgical treatment (posterior cervical fusion, anterior odontoid screw fixation), from 2015 to 2022. We excluded all polytraumatized patients (extremity fracture or associated spine fracture) and patients with diagnosis of displaced type II odontoid fracture during any clinical encounter.

Results: From 2015 to 2022, 516 patients were diagnosed with non-displaced type II odontoid fractures. The surgical rate was approximately 7.5%. Of the 39 patients undergoing surgery, 56% underwent C1-C2 arthrodesis and 44% underwent anterior odontoid screw fixation. No patient with an initially diagnosed non-displaced fracture experienced late displacement or catastrophic neurologic compromise. In our cohort, the nonunion prevalence was 2.5% amongst patients managed non-operatively. No patient with an isolated type II odontoid fracture nonunion underwent surgery.

Conclusion : Nonoperative management of non-displaced type II odontoid fractures is the preferred treatment modality in this cohort. C1-C2 fusion remains the most common surgical treatment modality to manage these fractures. There is no evidence that late displacement is common or expected in patients undergoing nonoperative management. No patient with a diagnosed fracture nonunion underwent surgery, which is consistent with current understanding that fracture nonunion does not represent treatment failure.