Introduction: Hangman’s fracture is a fracture of bilateral pars interarticularis of the axis. The mechanism is hyperexten¬sion with axial loading. Most hangman’s fractures can be treated using external immobilization. Surgery is reserved for fractures that fail immobilization, disc disruption, displacement, or neurological injury. Surgi¬cal options are anterior C2-3 anterior cervical discectomy and fusion (ACDF) or posterior (C1-3) spinal fusion. Both have comparable outcomes. Here we present a series of cases with hangman’s fractures with atypical features that failed C2-3 ACDF.

Methods: Case 1: A 48 years old female with hangman’s fracture (left pars & right pedicle) after motor vehicle accident. She underwent C2-3 ACDF. On 2 months follow up X-rays showed new C2-3 anterolisthesis (9mm) with nonunion. The patient underwent a C3 corpectomy with C2-4 arthrodesis followed by a C1-C4 posterior instrumentation. Case 2: A 54 years old male with hangman’s (bilateral pedicular involvement) and C1 bilateral posterior arch fractures after a bike accident. The C2-3 disc was disrupted. He underwent C2-3 ACDF. Immediate postoperative x-rays showed worsening of C2-3 anterolisthesis. He underwent a C1-C3 posterior instrumentation. Case 3: A 69 years old male with hangman’s fracture (right pedicle & left pars) after a motor vehicle accident. The C2-3 disc was disrupted. He underwent C2-3 ACDF. Immediate postoperative x rays showed worsening of C2-3 anterolisthesis. He underwent a C1-C3 posterior instrumentation.

Results: Cases 1,2,3 were followed up with x-rays as follows: 8,12, 3 months respectively. X-rays showed stable instrumentation and solid bony fusion.

Conclusions: Anterior approach can be used for the treatment of some hangman’s fractures. Here we present cases that failed anterior fusion. We hypothesize that the presence of unilateral or bilateral pedicular involvement (atypical features) may lead to failure of anterior approach and that posterior fusion is indicated.

Patient Care: We strongly believe that this abstract will raise awareness of this potential surgical complication among practicing neurosurgeons. We hope this further studies will be conducted to validate our findings will which results in a change in the treatment paradigms of hangman's fractures.

Learning Objectives: 1. Hangman’s fracture with atypical features is recognizable on imaging 2. Treatment paradigm for hangman’s fracture with atypical features differs from that for typical hangman’s. 3. There is limited data on the best treatment option for hangman’s with atypical features.

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