Surgery of Spinal Deformities Rizzoli Orthopaedic Institute Bologna, Italy Surgical options in progressive scoliosis in pediatric patients with Neurofibromatosis type I Konstantinos Martikos, Francesco Lolli, Mario Di Silvestre MD, Alfredo Cioni, Stefano Giacomini, Mauro Spina, Tiziana Greggi,
Background Spinal deformity Spinal deformity in approximately 49% of patients with NF1 (1) 2 types of scoliosis in NF1 Non-dystrophic progressession similar to AIS treated as an AIS Dystrophic (2) more severe osseous abnormalities that complicate treatment early and aggressive surgical intervention is necessary
Dural ectasia bone erosion meningocele Vertebral scalloping <3mm thoracic spine <4mm in lumbar spine Background Dystrophic alterations Rib Penciling may cause paralysis Dumbbell lesion canalar neurofibromas expand through foramen
Orthopedic featuresModulation a process by which dystrophic characteristics develop over time (3) C. S. Female 5 yrs C. S. Female 10 yrs Modulation should be carefully assessed to prevent progression of deformity in young patients under the age of 10 years. Modulation rate is reported 65%; Occures in 81% of NF-1 patients with scoliosis before the age of 7.
Retrospective evaluation of surgical outcomes 23 consecutive patients, between 4 and 11 years, with severe progressive scoliosis in NF1. Average Cobb angle before surgery: 48° (min. 38°, max. 82°) Skeletal maturity according to Risser sign was 0 in all patients. Mean age at first surgical procedure: 9.1 years (min. 8 yrs, max. 11yrs) Mean follow up: 4 years (min. 18 mos, max 15 yrs). Materials and methods Group A (14 patients): Thoracic kyphosis inferior to 50°. Posterior only instrumentation. Group B (9 patients): Thoracic kyphosis superior to 50°. Combined anterior and posterior instrumented arthrodesis. Patients retrospectively divided into 2 Groups
Average correction rate of Cobb angle: 60%. Overall complication rate: 24%. Major complication rate was 7%. Crankshaft phenomenon observed in 3 Group A patients (21%); in these cases anterior arthrodesis was performed after a mean 15 mos period from first surgical procedure. Fusion failure observed in 1 Group B patient, treated by revision of posterior instrumentation. Clinical and radiographic evaluation at follow up showed good outcome in terms of deformity progression and quality of life. Results
Patient M. M. Female , age 8 right convex thoracic scoliosis with hyperkyphosis highly dystrophic
Patient M. B. Female , age 9 Combined anterior and posterior arthrodesis with autologus bone graft
2009, age 13 4-year follow-up Patient M. M. Female , age 15 6-year follow-up
In highly dystrophic progressive deformities in pediatric age: early arthrodesis should be performed early approach should be aggressive (anterior and posterior fusion) Posterior accessAnterior access Conclusions
Surgical treatment of early progressive spinal deformities in NF1 is a demanding procedure with un uncertain outcome Revision surgery may be necessary due to the ongoing dystrophic alterations that may occur over time (modulation). Conclusions 13-year-old male: double-access arthrodesis with anterior fibular graft 21 years follow up: erosion spares only anterior bone graft
None of the authors has any potential conflict of interest