Spinal surgery involving direct decompression with exposure of the dura mater
Conditions
Interventions
None listed
Sponsors
Japan Community Healthcare Organization Osaka Hospital
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: Patients who meet all of the following criteria: 1. Patients undergoing spinal surgery (cervical, thoracic, or lumbar) at our institution, including endoscopic decompression, open decompression, and direct decompression performed with fusion procedures. 2. At least one intervertebral level in which the dura mater is exposed intraoperatively and the ligamentum flavum (or surrounding tissues) is dissected from the dura. 3. The target intervertebral level must not be a revision site (no previous surgery at the same level). Cases may be included even if other levels in the same operation are revision sites, provided that the target level is a primary surgery site. 4. Preoperative MRI (including axial T1-weighted images) and CT obtained as part of routine clinical care at our institution.
Exclusion criteria
Exclusion criteria: Patients (or intervertebral levels) meeting any of the following criteria will be excluded: 1. Revision surgery at the same intervertebral level. 2. Fusion procedures intended only for indirect decompression (e.g., cases or levels in which direct decompression exposing the dura mater is not performed). 3. Conditions in which the mechanism of adhesion formation differs substantially from that of typical degenerative disease, such as infection, tumor, trauma, or inflammatory disorders. 4. Preoperative imaging not suitable for evaluation. 5. Refusal of participation in the study by the patient (or legally authorized representative).
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Association between intraoperative dural-ligamentum flavum adhesion grade (0-3) and preoperative imaging parameters. Definition of adhesion grades Grade 0 (none): Easily separable with blunt dissection, with minimal resistance. A clear dissection plane between the dura mater and the ligamentum flavum can be readily created. Grade 1 (mild): Some resistance or adherence is present, but separation is possible mainly with blunt dissection (sharp dissection is generally not required). Grade 2 (moderate): Repeated blunt dissection is required. Partial sharp dissection or leaving a thin layer at the adhesion site may occasionally be necessary. Grade 3 (severe): A dissection plane is difficult to obtain with blunt dissection, indicating near fusion of the tissues. Sharp dissection or a change in surgical strategy (e.g., leaving the adhesion in place) is required. | — |
Secondary
| Measure | Time frame |
|---|---|
| Interobserver agreement of adhesion grading (primary surgeon vs assistant surgeon): weighted kappa coefficient. Performance of models predicting severe adhesion (e.g., Grade 3 or Grade 2 and above), evaluated by the area under the receiver operating characteristic curve (AUC). Association between adhesion grade and intraoperative outcomes such as incidental dural tear, need for sharp dissection, operative time, and estimated blood loss. Differences in imaging parameters and clinical outcomes between adhesion cases and matched controls in matched analysis. | — |
Countries
Japan
Contacts
Public ContactShota Takenaka
Japan Community Healthcare Organization Osaka Hospital Department of orthopaedic surgery
Outcome results
None listed