Case Reports
. 2021 Dec 20;13(12):e20550.
doi: 10.7759/cureus.20550.
eCollection 2021 Dec.
Affiliations
Affiliations
- 1 Orthopaedic Surgery, Tan Tock Seng Hospital, Singapore, SGP.
- 2 Orthopaedic Surgery, Khoo Teck Puat Hospital, Singapore, SGP.
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Case Reports
Tamara L Soh et al.
Cureus.
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. 2021 Dec 20;13(12):e20550.
doi: 10.7759/cureus.20550.
eCollection 2021 Dec.
Affiliations
- 1 Orthopaedic Surgery, Tan Tock Seng Hospital, Singapore, SGP.
- 2 Orthopaedic Surgery, Khoo Teck Puat Hospital, Singapore, SGP.
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Abstract
Instrumented fusion with rods and pedicle screws is often performed for the surgical treatment of adult spinal deformity (ASD). One of the complications of such long construct fusions is that of pseudoarthrosis, which can present with implant loosening, failure, and rod breakage. However, migration and spontaneous extrusion of the rod is relatively rare and has yet to be reported in the literature. We report a gentleman with previous long construct instrumented fusion done six years ago for ASD, who presented with gluteal pain. Radiographs revealed rod breakage and caudal migration towards the left gluteal region. He subsequently reported spontaneous extrusion of the broken rod through the gluteal skin, without the need for surgical removal. This case is reported for its rarity and to raise awareness about the rare occurrence of rod migration after breakage that can lead to potential complications if left unattended.
Keywords:
adult spinal deformity; implant failure; pseudoarthrosis; scoliosis; spinal instrumentation.
Copyright © 2021, Soh et al.
Conflict of interest statement
The authors have declared that no competing interests exist.
Figures

Figure 1. A: AP radiograph of the…
Figure 1. A: AP radiograph of the lumbar spine demonstrating broken rods bilaterally with migration…
Figure 1. A: AP radiograph of the lumbar spine demonstrating broken rods bilaterally with migration of the rod on the left. B: Lateral radiograph of the lumbar spine demonstrating caudal migration of the rod into the soft tissue.
AP, anterior-posterior

Figure 2. A: Coronal CT images demonstrating…
Figure 2. A: Coronal CT images demonstrating pseudoarthrosis at L5/S1 and absence of the broken…
Figure 2. A: Coronal CT images demonstrating pseudoarthrosis at L5/S1 and absence of the broken rod on the left. B: Sagittal CT image showing pseudoarthrosis at L5/S1.

Figure 3. Clinical photograph demonstrating a healed…
Figure 3. Clinical photograph demonstrating a healed wound over the left gluteal region from the…
Figure 3. Clinical photograph demonstrating a healed wound over the left gluteal region from the extruded rod.

Figure 4. A: AP of the spine…
Figure 4. A: AP of the spine demonstrating absence of the broken rod on the…
Figure 4. A: AP of the spine demonstrating absence of the broken rod on the left, and a broken rod on the right below the L5 screw. B: Lateral radiograph of the spine showing the absence of the broken rod on one side, with the contralateral rod broken but not migrated.
AP, anterior-posterior
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