Hyperextension-distraction fractures in ankylosing and spondylotic spines: injury profile and treatment results.

STUDY

DESIGN

Case series study.

PURPOSE: To describe demographic metrics, and clinical and radiographical outcomes of surgical treatment in patients with ankylosed spine (ASP) such as diffuse idiopathic skeletal hyperostosis (DISH) or ankylosing spondylitis (AS) and non-ankylosed spines (NAS) suffering from hyperextension-distraction spine fractures.

METHODS

Patients diagnosed with hyperextension-distraction fractures between 2012 and 2020 were identified. A retrospective analysis of clinical and surgical data was performed. Similarities between patients with ASP and NAS were evaluated by Fisher's exact test.

RESULTS

Of the 22 patients, 13 had ASP (10 patients with DISH, 3 AS) and nine NAS. Most of these injuries involved the thoracolumbar spine (45.4%). All patients with NAS presented some sign of spondylosis: facet joint degeneration, intervertebral osteochondrosis, and anterolateral osteophytes. None of the patients with NAS and 30.7% with ASP suffered low-energy mechanisms (p = .11). All the patients with NAS and 61% of the patients with ASP had associated injuries (p = .04). On average, the instrumented levels were four (range, 2-6), achieving a fusion rate of 94.7% in all groups. Most of the ASP and NAS presented post-operative complications respectively (p = .65).

CONCLUSION

Hyperextension-distraction spine fractures are not unique in ASP. In patients with spondylosis and high-energy accidents, we should suspect those fractures and rule out associated injuries, fractures in other vertebral segments, and acute spinal cord injury. The four-level instrumentation achieved an effective fusion rate in all patients.