Kyphoscoliosis: Exploring Clinical Outcomes Of Sequential And Conventional Correction
Overview
Conventional correction techniques posed substantial challenges and heightened neurological risks in addressing severe and rigid kyphoscoliosis. In response, a novel approach termed sequential correction was developed. This study aimed to compare the clinical outcomes between sequential correction and conventional correction for severe and rigid kyphoscoliosis.
Conducted as a case–control study from January 2014 to December 2019, the research included 36 adults undergoing surgical correction for this condition, with 20 undergoing conventional correction and 16 opting for sequential correction. Evaluation parameters encompassed major curve Cobb angle, kyphotic angle, coronal imbalance, and sagittal vertical axis. Patient-reported outcomes, such as Oswestry disability index scores and SRS-22 questionnaire responses, were also documented. Statistical analyses, including independent samples t-tests and Mann–Whitney U tests, were applied to discern differences.
In the conventional correction group, preoperative major curve Cobb angle averaged 122.50 degrees, reducing to 40.35 degrees immediately post-surgery and reaching 43.95 degrees at the final follow-up. The corresponding kyphotic angle started at 97.45 degrees, decreased to 34.45 degrees post-surgery, and stabilized at 38.30 degrees at the final follow-up. In the sequential correction group, preoperative major angle was 134.44 degrees, diminishing to 44.56 degrees post-surgery and reaching 46.25 degrees at the final follow-up. The kyphotic angle started at 112.31 degrees, decreased to 39.00 degrees post-surgery, and stabilized at 40.38 degrees at the final follow-up. Both groups exhibited significant improvements in major curve Cobb angle and kyphotic angle, with no notable differences between them (p > 0.001). Postoperative self-reported quality of life scores improved, showing no significant differences between the two groups. Complication rates were 55% for conventional correction and 43.75% for sequential correction, with no significant difference observed. This study underscores the effectiveness and comparable outcomes of sequential correction, providing valuable insights into refining treatment approaches for severe and rigid kyphoscoliosis.
Introduction
This study delves into the challenges of treating severe and rigid kyphoscoliosis in adults, characterized by a major curve Cobb angle of ≥90 degrees and limited flexibility. Conventional correction techniques, often associated with high neurological risks, have been the standard. However, a novel approach called sequential correction has emerged. Unlike conventional methods, sequential correction employs a multi-step process to enhance correction precision. The study aims to describe, assess efficacy, and compare the clinical outcomes of sequential correction with conventional techniques for severe and rigid kyphoscoliosis.
Severe and rigid kyphoscoliosis, marked by a major curve Cobb angle of ≥90 degrees and restricted flexibility, poses significant challenges in treatment, primarily due to the associated high risk of neurological complications. Traditional correction techniques, including three-column osteotomies like pedicle subtraction osteotomy (PSO) and vertebral column resection (VCR), have been commonly employed. Despite their efficacy, these methods involve the use of only two long rods to correct deformities, maintaining coronal and sagittal alignment, and thus remain challenging.
In recent years, a pioneering technique known as sequential correction has been introduced to address the limitations of conventional methods. The sequential correction approach divides key correction procedures into multiple steps, providing a more nuanced and precise correction for severe and rigid kyphoscoliosis. This study sets out to achieve three main objectives:
(i) Elucidate the processes involved in both conventional correction and sequential correction for treating severe and rigid kyphoscoliosis,
(ii) Evaluate the effectiveness and feasibility of these correction methods,
(iii) Compare the clinical outcomes between sequential correction and conventional correction for this challenging spinal deformity. This comprehensive exploration aims to contribute valuable insights into advancing treatment strategies for severe and rigid kyphoscoliosis.
Methods
This study focused on severe and rigid kyphoscoliosis in adults, characterized by a major curve Cobb angle ≥90 degrees and flexibility ≤30%. The research compared two correction methods—conventional correction and sequential correction—applied to 36 adult patients between January 2014 and December 2019. Inclusion criteria encompassed adherence to ethical standards and the Declaration of Helsinki, with informed consent obtained.
Surgical procedures, approved by the institutional review board, utilized a posterior approach with intraoperative neurophysiological monitoring. The conventional correction group (20 patients) underwent pedicle screw implantation, facetectomy, and either grade 4 spinal osteotomy or posterior vertebral column resection (PVCR). Short segmental rods were utilized, and a long rod inserted to achieve spinal stability. In the sequential correction group (16 patients), a six-step process included screw placement, three-column osteotomy, major curve correction, short segmental instrumentation, rod cantilever technique, and integration with long rods.
Clinical examinations and radiographs were conducted preoperatively, postoperatively, and during follow-ups. Parameters such as major curve Cobb angles, kyphotic angles, coronal imbalance, C7 sagittal vertical axis, and fusion were measured. Self-reported health-related quality of life assessments, including Oswestry Disability Index scores and Scoliosis Research Society-22 questionnaire responses, were collected preoperatively, postoperatively, and at the final follow-up. The study provides valuable insights into surgical techniques and clinical outcomes for severe and rigid kyphoscoliosis correction.
Statistical Analysis
Statistical analysis for the study was conducted using SPSS 22.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics, mean, and standard deviation were employed to present variables. The normal distribution of data was assessed using the Kolmogorov–Smirnov test. For normally distributed data, independent samples t-test was applied to compare group differences, while nonparametric tests, such as the Mann–Whitney U test and Wilcoxon signed-rank test, were utilized for non-normally distributed data. A significance level of p < 0.05 was established for statistical significance. This approach allowed for a comprehensive analysis of the data, ensuring robust statistical comparisons between groups.
Results
The study evaluated the radiological and clinical outcomes of patients with severe and rigid kyphoscoliosis undergoing either conventional correction or sequential correction techniques. The mean major curve Cobb angle and kyphotic angle significantly improved in both groups, with no significant differences between them (p > 0.001).
Bony fusion of the osteotomy was observed by 6 or 12 months post-surgery. Clinical outcomes, as measured by the Oswestry Disability Index (ODI) and Scoliosis Research Society-22 (SRS-22) questionnaire, showed significant improvement in both groups at the final follow-up, with no significant differences between them.
Complications were reported in both groups, with a slightly lower total complication rate in the sequential correction group (43.75%) compared to the conventional correction group (55%), although the difference was not statistically significant. The findings suggest that both correction techniques are effective and safe for severe kyphoscoliosis, with sequential correction showing a potential advantage in terms of complications.
The study focused on comparing the outcomes of two surgical correction techniques, conventional correction and sequential correction, in adults with severe and rigid kyphoscoliosis. The inclusion criteria involved adults with a major curve Cobb angle of ≥90 degrees and flexibility ≤30%, excluding those with infections, tumors, or previous spinal surgery. A total of 36 adults underwent surgical correction between January 2014 and December 2019, with 20 in the conventional correction group and 16 in the sequential correction group.
Both correction techniques involved a posterior approach, and intraoperative neurophysiological monitoring was utilized. Conventional correction procedures included pedicle screws, facetectomy, and three-column osteotomies, such as grade 4 spinal osteotomy or posterior vertebral column resection (PVCR).
Sequential correction divided key correction steps into six stages, aiming for better correction of severe deformities. Radiological outcomes demonstrated significant improvement in major curve Cobb angle and kyphotic angle for both groups, with bony fusion achieved by 6 or 12 months postoperatively.
Clinical outcomes, assessed using the Oswestry Disability Index (ODI) and Scoliosis Research Society-22 (SRS-22) questionnaire, revealed significant improvements in both groups with no significant differences between them. Complications were observed in both groups, with a slightly lower total complication rate in the sequential correction group (43.75%) compared to the conventional correction group (55%), although this difference was not statistically significant.
The study indicated that both conventional and sequential correction techniques are effective in treating severe and rigid kyphoscoliosis, offering significant radiological and clinical improvements. While complications were present in both groups, the sequential correction technique showed a potential advantage with a slightly lower complication rate. The findings provide valuable insights into the surgical management of severe kyphoscoliosis, emphasizing the importance of individualized approaches to achieve optimal outcomes.
Conclusion
The study introduced a novel technique called sequential correction for treating severe and rigid kyphoscoliosis, alongside the conventional correction method. The clinical outcomes of sequential correction versus conventional correction were found to have no significant differences.
Surgical treatment is recommended for severe and rigid kyphoscoliosis to enhance pulmonary function and life expectancy. Different surgical approaches, including anterior, posterior, or a combination, have been employed, with techniques such as anterior and posterior vertebral column resection (VCR) providing effective correction. In the current study, grade 4 spinal osteotomy or posterior VCR was utilized for severe and rigid kyphoscoliosis treatment.
Conventional correction, involving grade 4 spinal osteotomy and posterior VCR, demonstrated excellent outcomes. A comparable technique, sequential correction, was introduced, and outcomes were discussed for both methods. Surgical correction via grade 4 spinal osteotomy or bone-disc-bone osteotomy (BDBO) has previously shown favorable outcomes. Sequential correction, which includes steps such as screw placement, three-column osteotomy, and major curve correction, was found to have similar clinical outcomes to conventional correction.
The study compared the outcomes of the two techniques, emphasizing that both maintained similar global coronal balance and sagittal alignment. Although the total complication rate for sequential correction was slightly lower than that of conventional correction, both methods were deemed effective. The conclusion suggested that sequential correction might be a safer alternative due to its slightly lower complication rate.