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Updated: Jun 30, 2026
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An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model
Published on: May 31, 2017
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Optimizing Rod Configuration Across Lumbar Pedicle Subtraction Osteotomy Site: Evolution of a High-Volume Deformity
David J Mazur-Hart1, Winward Choy1, Ping-Yeh Chiu2
1Department of Neurological Surgery, University of California - San Francisco, San Francisco , California , USA.
Operative Neurosurgery (Hagerstown, Md.)
|July 10, 2025
Summary
Using more rods in three-column osteotomy (3CO) for adult spinal deformity reduces mechanical complications like rod fracture. A seven-rod construct is recommended to maintain lordosis and minimize complications.
Area of Science:
- Spine surgery
- Orthopedic surgery
- Adult spinal deformity correction
Background:
- Three-column osteotomy (3CO) is crucial for adult spinal deformity but has high complication rates.
- Mechanical complications (MC) like rod fracture and pseudoarthrosis are significant concerns.
- Increasing use in an aging population necessitates optimizing surgical techniques.
Purpose of the Study:
- To evaluate the impact of multirod constructs across the 3CO level on MC.
- To assess the durability of radiographic outcomes after deformity correction.
- To determine the optimal construct configuration for minimizing MC and maintaining correction.
Main Methods:
- Retrospective review of 196 patients undergoing lumbar 3CO.
- Data collected: demographics, BMI, comorbidities, operative details, complications, and radiographic measurements.
- Analysis of construct configurations ranging from 4 to 7 rods.
Main Results:
- Higher MC rates observed in 4-rod constructs (P = .002), primarily due to rod fractures (P = .005).
- Significant loss of lordosis occurred with 4-rod constructs (6.2°) compared to 7-rod constructs (1.8°) (P = .009).
- Multirod constructs demonstrated improved stability and maintenance of correction.
Conclusions:
- The number of rods used in lumbar 3CO directly impacts MC rates.
- Increased rod usage effectively prevents the loss of lordosis over time.
- A 7-rod construct is recommended for lumbar 3CO to minimize MC and preserve lordosis.
Keywords:
Adult spinal deformityMechanical complicationPedicle subtraction osteotomySpinopelvic parametersThree-column osteotomyVertebral column resectionMore Related Videos
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