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Long-term growth and alignment after occipitocervical and atlantoaxial fusion with rigid internal fixation in young children. J Neurosurg Pediatr 2016 Jan;17(1):94-102 PMID: 26451720

Pubmed ID





OBJECT The long-term consequences of atlantoaxial (AA) and occipitocervical (OC) fusion and instrumentation in young children are unknown. Anecdotal reports have raised concerns regarding altered growth and alignment of the cervical spine after surgical intervention. The purpose of this study was to determine the long-term effects of these surgeries on the growth and alignment of the maturing spine. METHODS A multiinstitutional retrospective chart review was conducted for patients less than or equal to 6 years of age who underwent OC or AA fusion with rigid instrumentation at 9 participating centers. All patients had at least 3 years of clinical and radiographic follow-up data and radiographically confirmed fusion. Preoperative, immediate postoperative, and most recent follow-up radiographs and/or CT scans were evaluated to assess changes in spinal growth and alignment. RESULTS Forty children (9 who underwent AA fusion and 31 who underwent OC fusion) were included in the study (mean follow-up duration 56 months). The mean vertical growth over the fused levels in the AA fusion patients represented 30% of the growth of the cervical spine (range 10%-50%). Three different vertical growth patterns of the fusion construct developed among the 31 OC fusion patients during the follow-up period: 1) 16 patients had substantial growth (13%-46% of the total growth of the cervical spine); 2) 9 patients had no meaningful growth; and 3) 6 patients, most of whom presented with a distracted atlantooccipital dislocation, had a decrease in the height of the fused levels (range 7-23 mm). Regarding spinal alignment, 85% (34/40) of the patients had good alignment at follow-up, with straight or mildly lordotic cervical curvatures. In 1 AA fusion patient (11%) and 5 OC fusion patients (16%), we observed new hyperlordosis (range 43°-62°). There were no cases of new kyphosis or swan-neck deformity, evidence of subaxial instability, or unintended subaxial fusion. No preoperative predictors of these growth patterns or alignment were evident. CONCLUSIONS These results demonstrate that most young children undergoing AA and OC fusion with rigid internal fixation continue to have good cervical alignment and continued growth within the fused levels during a prolonged follow-up period. However, some variability in vertical growth and alignment exists, highlighting the need to continue close long-term follow-up.

Author List

Kennedy BC, D'Amico RS, Youngerman BE, McDowell MM, Hooten KG, Couture D, Jea A, Leonard J, Lew SM, Pincus DW, Rodriguez L, Tuite GF, Diluna ML, Brockmeyer DL, Anderson RC, Pediatric Craniocervical Society


Sean Lew MD Chief, Professor in the Neurosurgery department at Medical College of Wisconsin


2-s2.0-84971376314   16 Citations

MESH terms used to index this publication - Major topics in bold

Atlanto-Axial Joint
Cervical Vertebrae
Child, Preschool
Follow-Up Studies
Fracture Fixation, Internal
Occipital Bone
Retrospective Studies
Spinal Curvatures
Spinal Fusion
Treatment Outcome
jenkins-FCD Prod-310 bff9d975ec7f2d302586822146c2801dd4449aad