The impact of fusion on adjacent levels in cervical spine injuries: Is it really important?

Kasimatis, Georgios B.; Michopoulou, Sofia; Boniatis, Ioannis; Dimopoulos, Panagiotis; Panayiotakis, Georgios; Panagiotopoulos, Elias

doi:10.1016/j.clineuro.2009.08.028

« Previous Next »Clinical Neurology and Neurosurgery
Volume 111, Issue 10 , Pages 816-824, December 2009

The impact of fusion on adjacent levels in cervical spine injuries: Is it really important?

Georgios B. Kasimatis
- Department of Orthopaedic Surgery, University Hospital of Patras, Patras, Greece
- Corresponding author at: 14 Karagiorgi st., 14121 Iraklio Attikis, Athens. Tel.: +30 6972311623/+30 2610 999556; fax: +30 2610 994579.
Sofia Michopoulou
- Department of Medical Physics and Bioengineering, University College London, London, United Kingdom
Ioannis Boniatis
- Department of Medical Physics, University of Patras School of Medicine, Patras, Greece
Panagiotis Dimopoulos
- Department of Radiology, University Hospital of Patras, Patras, Greece
Georgios Panayiotakis
- Department of Medical Physics, University of Patras School of Medicine, Patras, Greece
Elias Panagiotopoulos
- Department of Orthopaedic Surgery, University Hospital of Patras, Patras, Greece

Received 6 March 2009; received in revised form 17 July 2009; accepted 11 August 2009.

Abstract

Objective

Although the literature on degenerative disease of the cervical spine contains numerous articles studying the changes on levels adjacent to a fusion, there exist very few such studies concerning cervical spine stabilization for trauma.

Methods

Over a 16-year period (1989–2005), one hundred and twelve patients underwent stabilization of the lower cervical spine (C3–T1) for subaxial cervical spine injuries, either with an anterior or posterior procedure, or both. Eighty-one patients with adequate follow-up were included in the study and 3 groups were identified: Group A, consisting of 8 patients who underwent anterior stabilization and developed Adjacent Level Ossification Development (ALOD), Group B, comprising 53 patients who were anteriorly plated but who did not develop ALOD and Group C, comprising 20 patients who received posterior stabilization.

Results

Eight out of 61 patients (13.1%) who were anteriorly operated developed ALOD in 11 adjacent levels (Group A). Severe (grade 3) ossification was noted in 6/8 patients at the cranial adjacent level, and in 2/8 patients at the caudal one. Three out of 8 patients presented with early ALOD at 3, 4 and 18 months respectively. Despite the radiographic abnormalities showing ossification, all the patients had an uncomplicated course without symptoms. All the radiographs of Group B and Group C patients demonstrated grade 0 ossification for both the cranial and caudal adjacent levels.

Conclusion

Adjacent-level ossification in cervical spine injuries may appear very early in the postoperative period and it can have a different course than in the degenerative disc disease population, at least in some patients. The first cephalad level adjacent to a fusion appears to be at greater risk. However, even when ALOD is evident radiographically, it very rarely produces any symptoms.

Keywords: Cervical spine injury, Cervical fusion, ADCF, Adjacent segment disease, Adjacent segment ossification, Cervical spine stabilization