Risk Factors for Postoperative Spinal Epidural Hematoma Following Posterior Thoracic Spinal Surgery in a Single Institute

Study Overview
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Brief Summary
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This is a retrospective, observational single-center study. The studies is to investigate the incidence of posterior epidural spinal hematoma(PSEH) and recognize the risk factors for it in a cohort of patients undergoing posterior thoracic surgery in isolation.

Detailed Description
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The study enrolled patients from January 2010 to December 2019, patients who developed PSEH after posterior thoracic surgery and underwent the hematoma evacuation. For each PSEH patients, 2 or 3 controls who did not develop the PSEH, underwent the same procedures of similar complexity at the same section of thoracic spine in the same period were collected. The preoperative and intraoperative factors, blood pressure related factors and radiographic parameters were collected to identify possible risk factors by comparing between two groups.

Official Title
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Risk Factors for Postoperative Spinal Epidural Hematoma Following Posterior Thoracic Spinal Surgery in a Single Institute

Conditions
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Spinal Epidural Hematoma, Thoracic Surgery

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects satisfying the following criteria will be considered eligible for enrollment in this study: Patient is ≥ 18 years and < 80 years of age; Patient who received thoracic decompression surgery via posterior approach Patient who diagnosed as symptomatic spinal epidural haematoma and received revision surgery. Exclusion Criteria: Thoracic spinal stenosis caused by trauma, tumor, infectious, deformity and other disease; Symptomatic spinal epidural haematoma happened at cervicothoracic and thoracolumbar junction; Initial surgeries were performed at other hospital; Incomplete clinical data.
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 |
| --- | --- |
| Symptomatic spinal epidural hematoma Group<br>Patients who performed thoracic decompression surgery and developed neurological deficit after surgery due to the symptomatic spinal epidural hematoma were enrolled into case group. | |
| Control group<br>hose who did not develop the symptomatic spinal epidural hematoma, underwent the same procedures of similar complexity at the same section of thoracic spine in the same period (the same year or the following year) were randomly selected from the pool of patients. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Large local kyphosis angle | The local kyphosis angle was determined by the measurement of the Cobb angle. Large local kyphosis angle creates a narrow space between the paravertebral muscles and spinal cord, especially in muscles with edema after surgery. Large local kyphosis angle is considered as a risk factor for symptomatic spinal epidural hematoma | 6 months | 
| High occupying ratio of cross-sectional area | Severe compression on spinal epidural venous plexus lead to poor elasticity of the vessel wall and impedance of blood flow. As a result, dilatation of the spinal epidural venous plexus are more often in symptomatic spinal epidural haematoma patients, contributing to the development of haematoma. Therefore, high occupying ratio of cross-sectional area is considered as a risk factors for symptomatic spinal epidural hematoma. | 6 months | 
| Cerebrospinal fluid leakage | Cerebrospinal fluid leakage provides internal pressure for the dura and its own contents, and a small haematoma does not easily induce symptoms. It is the author's hypothesis that if cerebrospinal fluid leakage occurs intraoperatively, internal pressure loss, even in a small hematoma, can cause compression. Therefore, cerebrospinal fluid leakage are considered as a risk factor for symptomatic spinal epidural hematoma | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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symptomatic spinal epidural hematoma, posterior thoracic surgery, local kyphosis angle, occupying ratio of cross-sectional area, cerebrospinal fluid leakage.