Kyphectomy followed by self-sliding pedicle screw and translumbosacral rod impaction and fixation: a novel growth-friendly technique in myelomeningocele patients.

Abstract

Introduction: Congenital lumbar kyphosis is present in about 15% of patients with myelomeningocele. Worsening of deformity with complications such as chronic skin ulcers and bone exposure is common. In patients under 8 years of age, treatment becomes even more challenging: in addition to resecting the apex of the kyphotic deformity, we should ideally stabilize the spine with fixation methods that do not interrupt the growth of the rib cage, associated with the challenging pelvic fixation in this population. The emergence of growth-friendly techniques has greatly benefited patients with early-onset deformity, allowing for correction and control of deviation without interrupting trunk growth, which is often already compromised in these patients. We describe the surgical technique and present preliminary clinical outcomes for a novel approach which combines self-sliding screws that allow for trunk growth with impaction of translumbosacral rods for distal fixation.

Methodology: Candidates for the technique were patients with myelomeningocele and congenital lumbar kyphosis, inability to assume supine position, and a history of skin ulcers, recurrent osteomyelitis and poor weight gain. They all lacked sensory or motor function below the level of the myelomeningocele. They underwent the same reconstruction technique after kyphectomy which combines self-sliding screws that allow for trunk growth with impaction of the translumbosacral rods for distal fixation.

Results: Case 1: Female; 4.5 years old at surgery; 5 year follow-up. 1 complication: loosening of one blocker. The child is doing well and did not require surgical revision. Mean growth per year: 9.5 mm. Case 2: Male; 7.4 Years old at surgery; 4 year follow-up. 1 complication: post-surgical infection which required 2 debridements in the operating room and prolonged antibiotic therapy. Mean growth per year: 6 mm. Case 3: Female; 5.5 Years old at surgery; 27 month follow-up. No complications reported so far. Mean growth per year: 9.42 mm. None of the cases showed signs of sacral osteolysis or rod migration.

Discussion / conclusion: To our knowledge, this is the first study that combines sliding screws with translumbosacral rod impaction. Although this technique has proven to be safe and effective, we are aware that the number of cases is limited and the follow-up is short. Further studies are necessary to confirm the method.