Hemivertebra Resection and Spinal Arthrodesis by Single-Stage Posterior Approach in Congenital Scoliosis and Kyphoscoliosis: Results at 9.6 Years Mean Follow-up.

BACKGROUND: Congenital kyphoscoliosis due to hemivertebra is generally treated surgically because of high risk of curve progression and high risk of nervous system complications. Modern posterior access surgical techniques, including total hemivertebra resection, can completely correct deformity without additional anterior access surgeries. The purpose of this study was to evaluate midterm results of hemivertebra resection and spinal arthrodesis; the hypothesis was that it is a safe, effective, and reproducible procedure. MATERIALS AND METHODS: From 2006 to 2019, hemivertebra resection and instrumented spinal arthrodesis with pedicle screws was performed on 82 patients with congenital vertebral deformities (62 scoliosis and 20 kyphoscoliosis) by posterior approach. Mean age at surgery was 8.6 years, and 22 patients were under 10 years of age. After stabilization patients have been braced for a period from 3 to 5 months. RESULTS: Mean follow-up was 9.6 years (range 1.2-12.8 years); mean kyphosis curve after surgery was reduced to 20° Cobb; and mean scoliosis curve was reduced to 11° Cobb. We experienced no major complications (postsurgical infection, instrumentation failure, severe neurological impairment, severe blood loss) at latest follow-up . CONCLUSION: We strongly advocate one-time posterior hemivertebra resection and arthrodesis as the most suitable surgical procedure for congenital scoliosis due to hemivertebra. Posterior approach interventions with pedicle screws instrumentation are less invasive than combined anterior-posterior approach interventions. We think that posterior approach procedures can lead to excellent deformity correction in both frontal and sagittal views, optimal stability, and low risk of nervous injury. CLINICAL RELEVANCE: Congenital scoliosis treatment is one of the most challeging conditions a spine surgeon has to face. We advocate that a one-stage posterior approach for hemivertebrectomy and fusion is a reliable, safe tachnique, whom excellent results remain stable at a mid/long-term follow-up. LEVEL OF EVIDENCE: Level 4.

Spine challenges in mucopolysaccharidosis.

PURPOSE: Mucopolysaccharidosis (MPS) are rare inherited metabolic diseases, causing lysosomal storage of mucopolysaccharides; clinical presentation involves skeletal system and particularly the spine. Anomalies include developing kyphosis at thoracolumbar junction, that can causes nervous symptoms, and dens hypoplasia with associated atlantoaxial subluxation that can cause myelopathy. We present our experience in the treatment of spine pathology in MPS. METHODS: Medical treatments of MPS seem to have little impact on spine disease: treatment of cervical instability often includes surgical decompression and stabilization, as in patient MPS1 that we present, while thoracic lumbar kyphosis is treated by bracing and, in severe cases, with surgery. Bracing is more effective in kyphosis under 40° Cobb. Our surgical cases with thoracic lumbar kyphosis over 40° Cobb, treatment include the first one ever described by only posterior approach with vertebrectomy in MPS and a case of lateral costo-transverse approach instrumented correction. RESULTS: Surgical patients had no major complications after surgery and CT scan at follow-up showed complete fusion without loss of correction, even if in a cervical case we used an adult rigid instrumentation in a four year-and-six month-old girl (11 years follow-up) and in thoracic lumbar kyphosis case treated by vertebrectomy due to diminutive anatomy we positioned interbody cage in suboptimal position. CONCLUSIONS: Bracing is a viable treatment strategy in thoracic lumbar kyphosis and can obtain good clinical results at medium terms follow-up even if kyphosis deformity remains in radiographs. Surgical treatment is effective in severe evolving cases both at cervical and thoracic lumbar level, main difficulties arose from unavailability of dedicated instrumentation in very young patient, as even smallest devices available are often too big.

Adolescent idiopathic scoliosis correction by instrumented vertebral arthrodesis with autologous bone graft from local harvesting without bone substitute use: results with mean 3 year follow-up.

PURPOSE: Bone substitutes' advantage is enhancing arthrodesis biologic support without further autologous bone graft harvested from other skeleton sites, as from posterior iliac crests; however, in our experience, bone substitutes' integration is often incomplete. METHODS: From 2012 to 2017, we operated 108 patients by posterior instrumented vertebral arthrodesis in adolescent idiopathic scoliosis (AIS) correction, mean main curve 80° Cobb, and mean age 12 years and 6 months, with all pedicle screws instrumentation in main curve/curves area and hooks at upper tip of implant; bone graft has been harvested only at vertebral level, without bone substitutes or autologous graft from other patient sites or allogenic bone graft. We matched this group with 98 patients previously operated in which we used calcium triphosphate. RESULTS: At 3 year mean follow-up, all patients in group treated with autologous bone graft only have complete and stable arthrodesis without loss of correction (mean curve 27° Cobb) or instrumentation failure. At 6 year mean follow-up in the group treated with autologous bone graft augmented by calcium triphosphate, 96 patients have stable arthrodesis without loss of correction (mean curve 24°), 1 case has implant break, and 1 case has 8° Cobb loss of correction. CONCLUSION: Bone substitutes are a further cost in arthrodesis surgery and suboptimal integration leaves foreign bodies on vertebras. Our experience shows that all pedicle screw instrumentation and bracing after surgery obtain stable correction showing in time a solid arthrodesis with autologous bone only, harvested at local site, without bone substitutes or further bone graft.

Treatment of severe scoliosis with posterior-only approach arthrodesis and all-pedicle screw instrumentation.

PURPOSE: Posterior-only approach arthrodesis by all-pedicle screw instrumentation has a correction rate similar to correction obtained by traditional combined anterior/posterior approach surgery and avoids the complications associated with the thoracic approach. METHODS: We treated 25 patients, with a mean age 16.5 years, with severe adolescent idiopathic scoliosis by posterior-only approach using all-screw instrumentation arthrodesis. Mean scoliosis curve in Cobb degrees was 95° Cobb. All cases were treated by the same senior surgeon, by free hand technique, without intraoperative neurophysiologic monitoring and spine navigation aids. RESULTS: Mean scoliosis curve after surgery was 37° Cobb. Mean follow-up was 4 years. No perioperative complications, curve progression or arthrodesis malunion were reported at the follow-up. CONCLUSIONS: Posterior spinal fusion with pedicle screw-only instrumentation obtains a good and stable correction of severe scoliosis; compared to hybrid instrumentation, it allows a greater coronal correction of the deformity and less correction loss at the follow-up.