Spine Journal - 2026-06-09 - Journal Article
Prophylactic Concave-side Decompression and Spinal Cord Medialization Reduces Neurological Complications in Severe Kyphoscoliosis with Type 3 Cord Morphology.
Dai Y, Lo YS, Liu D, Lin EE, Mao S, Liu Z, Qiu Y, Zhu Z, Shi B
Topics
Key Takeaway
Prophylactic concave-side decompression and spinal cord medialization (PCDM) before three-column osteotomy reduced permanent neurological deficits from 6.7% to 1.5% (p=0.046) in severe kyphoscoliosis with type 3 cord morphology.
Summary Depth
Choose how much analysis to show on this article page.
Summary
This study asked whether prophylactic multi-level concave laminae, pedicle, and costovertebral resection to create a medial transposition corridor before 3CO reduces neurological injury in type 3 cord morphology kyphoscoliosis. PCDM (n=132) was compared to standard 3CO alone (n=104) with equivalent baseline deformity severity and comparable final coronal and sagittal correction. PCDM yielded a 4.4-percentage-point absolute reduction in permanent neurological deficits (1.5% vs. 6.7%, p=0.046), lower IONM alert rates (8.3% vs. 20.2%, p=0.012), and higher neurological recovery in those with preoperative deficits (86.7% vs. 50.0%, p=0.009), without a significant difference in overall perioperative complication rates (13.6% vs. 19.2%, p=0.246).
Key Limitation
The retrospective design cannot exclude selection bias in which patients received PCDM, as surgeons may have preferentially applied the technique to anatomically more favorable cases despite comparable group-level radiographic parameters.
Original Abstract
BACKGROUND CONTEXT
Type 3 spinal cord morphology increases neurological injury risk during three-column osteotomy (3CO). Prophylactic Concave-side Decompression and Spinal Cord Medialization (PCDM) is proposed to relieve cord tension, but its clinical utility requires validation.
PURPOSE
To evaluate the neuroprotective efficacy of PCDM in patients with severe kyphoscoliosis and type 3 spinal cord morphology undergoing 3CO.
STUDY DESIGN
Retrospective comparative cohort study.
PATIENT SAMPLE
This study included 236 patients with severe kyphoscoliosis treated with 3CO.
OUTCOME MEASURES
Radiographic parameters, neurological status (Frankel grading), patient-reported outcomes (SRS-22), intraoperative neuromonitoring (IONM) alerts, and perioperative complications were analyzed and compared.
METHODS
The PCDM group (n=132) underwent prophylactic multi-level resection of concave laminae, pedicles, and costovertebral elements to create a medial transposition corridor before 3CO. The non-PCDM group (n=104) received standard 3CO alone.
RESULTS
Baseline demographics and preoperative radiographic profiles were comparable between groups. Both cohorts achieved substantial deformity correction. The PCDM group showed significant reductions in coronal Cobb angle (80.8° to 42.2°) and global kyphosis (71.7° to 27.6°), similar to the non-PCDM group (76.7° to 39.6° and 66.3° to 25.2°, respectively). Notably, the PCDM group exhibited a significantly lower rate of permanent neurological deficits compared to the non-PCDM group (1.5%, 2/132 vs. 6.7%, 7/104; p=0.046). IONM alert rates were also lower in the PCDM group (8.3% vs. 20.2%, p = 0.012). Among patients with preoperative deficits, neurological recovery was more frequent in the PCDM group (86.7% vs. 50.0%, p = 0.009). Perioperative complication rates were not significantly different (13.6% vs. 19.2%, p = 0.246).
CONCLUSION
PCDM appears to offer neuroprotective benefits in high-risk 3CO procedures for patients with type 3 spinal cord morphology, with reduced neurological complications and improved functional outcomes. Its use as a preparatory step prior to osteotomy may be considered as a beneficial adjunct in selected severe deformity cases.