Spinal osteotomies Nicholas D. Fletcher, MD Assistant Professor of Orthopedics Director of Spinal Quality/Outcomes Emory University Department of Orthopedics Children s Healthcare of Atlanta Atlanta, GA
Disclosures Research support: Harrison Foundation, Harms Study Group funding Paid consultant: Medtronic; Biomet/Zimmer Speakers Bureau: Medtronic; Biomet/Zimmer Unpaid consultant: Orthopaediatrics
What is an osteotomy? Bony resection designed to increase flexibility of spine or alteration of alignment
Who needs osteotomies? Ponte/PCO PSO VCR PCO PSO VCR Power + ++ +++ Complexity + ++ +++ Complications + +++ ++++++++++
Schwab Classification of osteotomies Spine 2013
Simple Facetectomy Type 1 - osteotomy
Ponte /Type 2 Posterior column osteotomy 10 /level
Pedicle Subtraction Osteotomy Type 3 Osteotomy 25-35 /level
Vertebral Column Resection Type 5-6 osteotomy
68 89 57 47 3 yrs post op
When to use? Facetectomy - for anatomic screw placement, landmarks, general increase in spinal flexibility Posterior Column Osteotomy - improved spinal flexibility Pedicle Subtraction Osteotomy - for severe sagittal or combined imbalance in the lumbar spine Vertebral Column Resection - severe rigid thoracic/lumbar deformity
Posterior Column Osteotomy Schwab Type 2
Basic Points PCO Facetectomy first Do as much as you can with a large rongeur Remove SP to base of lamina Open Ligamentum with small rongeur Kerrisons and small rongeur for resection Expose 1 level at a time to avoid errant assistants
Agabedi SA et al, 2015
Schwab Type 3 osteotomy Pedicle Subtraction
Pedicle Subtraction Osteotomy Best for correction of sagittal imbalance Can be used for combined deformity (coronal/sagittal) ~30 degrees of correction per level Best for lumbar deformities (nerve roots preserved) Rare in pediatric deformity surgery as lumbar spine typically flexible
Step 1 Wide Laminectomy Control Epidural Bleeding Surgicel FloSeal Cottonoid Check for Dural Tears
Step 2 Vertebral Exposure Spoon retractors Preserve Transverse process to help with bleeding Raytec can be used for hemostasis
Step 3 Pedicle Preparation Tap the pedicle 5.5 up to 7.5
Step 4 curette the pedicle and Burr (M8) vs curette Keep medial pedicle wall intact to protect dura Begin osteotome work before removal of medial wall expand window
Step 5 Osteotome work
Step 6 prepare the other side
Step 7 release dura from posterior Important to gently free ventral dura on both sides prior to fracture of posterior wall body
Step 8 Assemble temporary rod
Step 9 ventral wall fracture Can use reverse curette (Ebstein) or tamp 2 handed technique Have assistant mallet while maintaining pressure on posterior body
Remove residual bone and compress osteotomy
Vertebral Column Resection Let s be honest you won t likely do many Most common VCR in pediatrics is a hemivertebrectomy Used sparingly with addition of in situ distraction Better for thoracic deformity Requires true anterior column support to be a VCR
Primary additional steps VCR vs PSO Complete discectomy caudad and cephalad Nerve roots may be sacrificed (thoracic spine) Meticulous evaluation of posterior VB resection Temporary rods! Anterior column support to prevent shortening of spinal cord
Courtesy Dan Sucato, MD
Initial shortening of spine to prevent neural distraction
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Halo traction after anterior release Halo up to 1/2 body weight Start at 10 lbs and increase 5lbs/day Weekly X-rays Educate nurses on care and near checks 51
S2AI for NMS 52 Courtesy of Joe Stone
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Conclusions Osteotomy work is a continuum Primary decisions to perform related to 1. Deformity location 2. Magnitude 3. Flexibility 4. Surgical goals 5. EXPERIENCE AND COMFORT
Thank you! Nicholas.d.fletcher@emory.edu