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Updated: Jul 20, 2025
08:43
Imaging of the Microstructural Failure Mechanism in the Human Hip
Published on: September 29, 2023
869
Chance Fracture Pattern Presenting in Proximal Junctional Failure
Shea M Comadoll1, Kenneth J Holton, David W Polly
1From the Department of Orthopedic Surgery (Dr. Comadoll, Dr. Holton, Dr. Polly, Mr. Schmitz, Dr. Haselhuhn, Dr. Soriano, Dr. Martin, and Dr. Sembrano) and the Department of Neurosurgery (Dr. Polly and Dr. Jones), University of Minnesota, Minneapolis, MN.
Summary
Proximal junctional failure can occur as a Chance-type fracture after adult spinal deformity surgery. Risk factors include overcorrection of lumbar lordosis and specific upper instrumented vertebra (UIV) choices.
Area of Science:
- Spinal surgery
- Orthopedic surgery
- Radiology
Background:
- Proximal junctional failure (PJF) is a complication after spinal fusion.
- Chance-type fractures are a rare cause of PJF.
Observation:
- This case series reviewed 15 patients with PJF due to Chance-type fractures after spinal fusion for adult spinal deformity.
- No antecedent trauma was reported.
- Overcorrection of lumbar lordosis and specific upper instrumented vertebra (UIV) selection were noted.
Findings:
- The average age was 61.4 years, and fractures were identified a mean of 25.4 days post-operatively.
- 14 of 15 patients required extension of fusion.
- Salvage involved changing pedicle screw trajectory.
Implications:
- Suspicion for Chance-type fractures should be raised with specific radiographic findings (increased proximal junctional angle, pedicle widening).
- CT scans are recommended for diagnosis.
- Risk factors include low bone density, lordosis overcorrection, and UIV selection in corrected thoracolumbar kyphosis.
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