Improvise, adapt and overcome-challenges in management of pediatric congenital atlantoaxial dislocation

Abstract

Objective: Congenital atlanto-axial dislocation (CAAD) often manifests in younger age group. Softer bones, deformed joints and the concern of fusing multiple segments in growing age set apart this subset of patients from adults. Objectives of this manuscript are to discuss the challenges faced and subsequent solutions during multiplanar realignment and fusion (short segment) of C1-2 joints through a direct posterior approach in pediatric CAAD.

Patients & methods: 56 pediatric patients with CAAD were operated through a direct posterior approach in the last 4 years. The joints were drilled and manipulated to achieve multiplanar realignment. C1-2 joints were fused (short segment). The pre and post operative clinical and radiological data was compared.

Results: Atlanto-axial dislocation was irreducible in 35 and reducible in 21 patients. Forty-nine (87.5%) patients were partially or totally dependent. The joints in the irreducible groups were oblique and deformed. Nine patients had lateral angular dislocation, 3 had C1-2 spondyloptosis and 5 had significant vertical dislocation. Drilling and manipulation was feasible in all cases. The bones were soft and partly cartilaginous in the pediatric population. Techniques were modified to achieve optimal bony purchase subsequent to drilling the relatively small bones and prevent screw pull-outs during intraoperative manipulation for the problems we had faced in our initial cases. Despite the challenges in initial cases, realignment could be achieved in all. There was a significant improvement in follow up modified JOA score and 28 patients were independent at 4-month follow up. Two patients had partial redislocation at 4-month follow up.

Conclusions: Pediatric patients have deformed and oblique joints, thereby making complete spondyloptosis, severe vertical dislocation and lateral tilt common in this age group. Though pediatric bones are soft and small, it is possible to achieve multiplanar realignment by drilling and manipulation of C1-2 joints. The realignment and short segment C1-2 fusion in these patients has a good radiological and clinical outcome.

Keywords: Challenges; Congenital atlantoaxial dislocation; Manipulation; Multiplanar realignment; Outcome; Pediatric.