Learning Curve, Outcome Parameters, and MRI Assessment of Disc Evacuation After Transforaminal Percutaneous Endoscopic Lumbar Discectomy

Study Overview
=================
Brief Summary
-----------------
Transforaminal Percutaneous Endoscopic Lumbar Discectomy (TPELD) is a surgical technique for managing lumbar disc herniation. The procedure demands a steep learning curve with regards to clinical improvement and technical challenges for disc evacuation. This study was to evaluate learning curve, outcome parameters, and MRI assessment for successful procedure in single - center early experience of Transforaminal Percutaneous Endoscopic Lumbar Discectomy (TPELD). This study was a retrospective cohort study, involving patients who underwent TPELD in our institution hospital by a single surgeon.

Detailed Description
-----------------
Investigators reviewed clinical evaluation, C-arm shot, and post-operative MRI findings as parameters for evaluation. All data was taken from the patients' medical records with single-level LDH (Lumbar Disc Herniation) following TPELD. Patients with incomplete data and those who underwent revision surgery were excluded. The collected data were regarding the sociodemographic characteristics of the patients (age and gender), surgical time, pre-operative pain scale (1-10), postoperative pain scale, complications, and weight of the removed disc and ODI (Oswestry Disability Index) score. The preoperative pain scale was assessed within 48 hours before the surgery while the post-operative pain scale was assessed at one month and three months after the surgery. The reduction of pain was assessed, comparing the pre-operative pain scale and the post-operative pain scale at 1 month and 3 months follow up. Pre TPELD MRI data and 3 months post TPELD were collected to evaluate the percentage of disc removed referring to the quantification of the axial MRI by two independent radiology department personnel. The area of the bulging disc was measured using as many points as the user felt were necessary in order to trace a reasonable outline of disc herniation. All of the TPELD procedures are performed by a single spine surgeon with only using one type of endoscopic instrumentation in one level LDH. The surgeon was not involved during data collection and data were collected by independent assessors. The statistical analysis was performed using SPSS 23.0. investigator tested all the numeric variables with the Shapiro-Wilk test for the normality of distribution. The surgeon's learning curve was evaluated using negative curve-fit regression analysis (y = ae-bx+ c) described by Silva, et al (2013). Then all case are divided into two groups based on the surgical time: cases before and at reaching 50% proficiency (early group) and cases after reaching 50% proficiency (later group).

Official Title
-----------------
Learning Curve, Outcome Parameters, and MRI Assessment Of Disc Evacuation After Transforaminal Percutaneous Endoscopic Lumbar Discectomy: a Single Center Retrospective Cohort Study

Conditions
-----------------
Herniated Nucleus Pulposus

Intervention / Treatment
-----------------
* Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: patient with single level LDH treated with TPELD Exclusion Criteria: reoperation inclomplete medical record

Ages Eligible for Study
-----------------
Minimum Age: 24 Years
Maximum Age: 62 Years

Sexes Eligible for Study
-----------------
All

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Age<br>Patient age | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Gender<br>Patient's gender | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Surgical Time<br>Duration of surgery, begin from incision until skin closure | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Intraoperative Blood loss<br>Total blood loss during operation | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Length of Stay<br>Duration of hospitalization | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| VAS Pre-op<br>Pain scale measured with visual analog scale (VAS) prior to the operation | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| 1 Month VAS<br>Pain scale measured with visual analog scale (VAS) 1 month after the operation | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| 3 Month VAS<br>Pain scale measured with visual analog scale (VAS) 3 month after the operation | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Decrease VAS 1 month<br>Difference of VAS score within 1 month of evaluation | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Decrease VAS 3 month<br>Difference of VAS score within 3 month of evaluation | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Disc weight<br>Estimation of total disc weight | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Removed disc weight<br>weight of removed disc measured after operation | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|
| Percentage of Removed Disc<br>Percentage of removed disc as seen on the axial MRI | Procedure: Transforaminal Percutaneous Endoscopic Lumbar Decompression<br>* TPELD is procedure of percutaneous lumbar discectomy done under endoscopic setting<br>* Other names: TPELD;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Learning curve of surgeon based on the duration | Curve of milestone achieved by the surgeon in performing the procedyre | measured within 24 hours after procedure is done | 
| Learning curve based on removed disc | Curve of milestone achieved by the surgeon based on extracting targeted disc weight | measured within 24 hours after procedure is done | 
| Learning curve based on the C-arm shot | Curve of milestone achieved by the surgeon based on use of fluoroscopic imaging | measured within 24 hours after procedure is done | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain reduction after one month | We measured the pain with visual analog score (VAS) scale reduction on each patients (1-10) | 1 month after procedure | 
| Pain reduction after three month | We measured the pain with visual analog score (VAS) scale reduction on each patients (1-10) | 3 month after procedure |