Perspective Analysis of Coronal Imbalance in Degenerative Scoliosis

Study Overview
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Brief Summary
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Currently there is paucity of information on the prevalence of pre-operative coronal imbalance in patients with degenerative lumbar scoliosis (DLS) and its influence on surgical outcomes. This study aims to investigate in DLS, the prevalence of coronal imbalance, to propose a novel classification system and to investigate whether pre-operative coronal imbalance affects clinical outcomes following osteotomy. A total of 284 DLS patients were recruited.

Detailed Description
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A total of 284 DLS patients were recruited into this two-stage study, among which 69 patients were treated by posterior-only correction and the remaining 215 patients received conservative treatment. Using pre-operative long-cassette X-ray films, all patients were classified based on coronal balance distance (CBD) defined as the horizontal distance between C7 plumb line and central sacral vertical line: Type A, CBD < 3cm; Type B, CBD > 3cm and C7PL shifts to the concave side of curve; Type C, CBD > 3cm and C7PL shifts to the convex side of curve. The prevalence of pre-operative coronal imbalance was calculated for stage I study. Post-operative CBD in patients who received surgery was measured to evaluate clinical outcomes for stage II study.

Official Title
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Coronal Imbalance in Degenerative Lumbar Scoliosis

Conditions
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Scoliosis

Intervention / Treatment
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* Procedure: Posterior osteotomy correction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age > 50 years, diagnosis of DLS based on radiographies and previous medical history and Cobb angle >25°. Exclusion Criteria: -

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 82 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pre-operative group<br>Respectively recruited patients with DLS. Patients in this group were not surgically treatment. Only pre-operative radiographic parameters were measured. | |
| Surgically treated group<br>All DLS patients received posterior osteotomy correction of spinal deformity. The immediate post-operative radiographic measurements were performed. | Procedure: Posterior osteotomy correction<br>* The DLS patients underwent osteotomy including pedicle subtraction osteotomy (PSO) or Smith-Petersen osteotomy (SPO)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The relationship between coronal balance classification and immediate post-operative imbalance using radiographic measurements | This part of the study aims to analyze the immediate imbalance after surgery, most of the patients took post-operative films two weeks after surgery, but there were some patients who could not stand at that timepoint and the follow-up time was then at 3 months after surgery. | Up to 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relationship between post-operative imbalance and quality of life using quality of life questionnaires including SF-36, ODI and VAS | The quality of life measurements were obtained using questionnaires, and the correlations between coronal imbalance and quality of life were analyzed at 1 year follow-up. | Up to 1 year | 
| Prevalence of coronal imbalance in degenerative scoliosis using radiographic measurements | The prevalence of coronal imbalance was analyzed in this cross-sectional study. Only a small part of the patients were with longitudinal follow-up. Most of them were without follow-up. | Up to 2 year pre-operative follow-up |