A Prospective Study of Natural History and Clinical Outcomes for Basilar Invagination

Study Overview
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Brief Summary
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A Prospective Study of Natural History and Clinical Outcomes for Basilar Invagination

Detailed Description
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Since basilar invagination was reported, its pathogenesis has been considered both primary and secondary. Surgical treatment methods emerged in an endless stream, and a hundred schools of thought contend. However, the link between the symptoms and imaging has not been studied in detail. We prospectively enrolled patients with basilar depression, and then explored the natural history of the disease and the clinical outcomes of early intervention.

Official Title
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A Prospective Study of Natural History and Clinical Outcomes for Basilar Invagination

Conditions
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Basilar Invagination

Intervention / Treatment
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* Procedure: Posterior facet distraction and fusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BI discovered by the patient not incidentally; Patients with depression of the skull base caused by congenital skeletal developmental malformations and symptoms; The patient was initially treated in our center, and the interval between onset and treatment was at least 1 month or no treatment; The imaging diagnosis of BI meets the standard (3-5mm higher than the Chamberlain's line) Exclusion Criteria: secondary BI caused by trauma, pathological factors such as rheumatoid arthritis, hyperparathyroidism, osteogenesis imperfecta, rickets, osteomalacia, spinal cord tumors, tuberculosis, inflammation of adjacent structures, and simple AAD, odontoid body deformity, etc. spinal vascular disease, intervertebral disc herniation, tethered spinal cord disease and other diseases that may cause symptoms. Patients with incomplete imaging data or symptomatic data.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Goel A Type Basilar Invagination<br>1) ADI>3mm in adults, or ADI>5mm in child. | Procedure: Posterior facet distraction and fusion<br>* With the patient in prone position, cervical traction was only intraoperatively after anesthesia with weights of approximately 5-8 kg during surgery. Monitoring of the spinal cord with motor evoked potential and somatosensory evoked potential were used throughout the surgery. Using a posterior midline incision, the occiput to the C2 spinous process was surgically exposed, separated to the lateral edge of the C1-2 joint, and cut off at the C2 nerve root to expose the C1-2 articular surface Quantitative reduction techniques included the following steps .1) Facet joint release and cage implantation technique 2)Adjusting POCA by cantilever and occipitocervical fixation technique.<br>|
| Goel B Type Basilar Invagination<br>ADI<3mm in adults, or ADI<5mm in child. The stabilization in atlantoaxial could can be found. The tip of odontoid can exceed the Chamberlian's line， but not exceed the Wackenheim's line and Mcrae's line. | Procedure: Posterior facet distraction and fusion<br>* With the patient in prone position, cervical traction was only intraoperatively after anesthesia with weights of approximately 5-8 kg during surgery. Monitoring of the spinal cord with motor evoked potential and somatosensory evoked potential were used throughout the surgery. Using a posterior midline incision, the occiput to the C2 spinous process was surgically exposed, separated to the lateral edge of the C1-2 joint, and cut off at the C2 nerve root to expose the C1-2 articular surface Quantitative reduction techniques included the following steps .1) Facet joint release and cage implantation technique 2)Adjusting POCA by cantilever and occipitocervical fixation technique.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| improved symptoms | The symptoms improved after the opration or natural condition.（JOA scores and SF-12 scores） | 1 months postoperatively | 
| improved symptoms | The symptoms improved after the opration or natural condition.（JOA scores and SF-12 scores） | 3 months postoperatively | 
| improved symptoms | The symptoms improved after the opration or natural condition.（JOA scores and SF-12 scores） | 6 months postoperatively | 
| improved radiology | improved ADI, CCA, CTA ; The basilar invagination reduced | 1 months postoperatively | 
| improved radiology | improved ADI, CCA, CTA ; The basilar invagination reduced | 3 months postoperatively | 
| improved radiology | improved ADI, CCA, CTA ; The basilar invagination reduced | 6 months postoperatively | 
| operation complication | operation complication（Excessive bleeding, bronchopneumonia, vertebral artery injury ） | 1 months postoperatively | 
| operation complication | operation complication（Excessive bleeding, bronchopneumonia, vertebral artery injury ） | 3 months postoperatively | 
| operation complication | operation complication（Excessive bleeding, bronchopneumonia, vertebral artery injury ） | 6 months postoperatively |