Surgical Considerations for Percutaneous Endoscopic Lumbar Discectomy at L5/S1 Level with Quantified Assessment

Presented at SMISS Annual Forum 2018
By G. Fan
With Paresh Bang MS Orthopaedics, Bharat Dave , Devanand D ,

Disclosures: G. Fan None Paresh Bang MS Orthopaedics None, Bharat Dave None, Devanand D None,

Introduction:

Percutaneous endoscopic lumbar discectomy (PELD) is a popular minimally invasive technique for lumbar disc herniation (LDH), which can be divided as percutaneous endoscopic transforaminal discectomy (PETD) or percutaneous endoscopic interlaminar discectomy (PEID). At L5/S1 level, both PETD and PEID have been validated technique for LDH, even for cases with high crest, large facet joint, narrow foramen, and small disc space. However, it still remains unclear whether PETD is non-inferior or even superior to PEID for L5/S1 cases, especially when foraminoplasty and navigation technique have been adopted.

Aims/Objectives:

The aim of the current retrospective study is to quantify a single surgeon’s experience of 72 PELD cases at L5/S1 level.

Methods:

we retrospectively review the medical data and identified eligible patients receiving PEID or PETD at L5/S1 level by a single surgeon. All included patients were divided into PETD group and PEID group. Additionally, patients in PETD group could be further divided into subgroups, namely navigated PETD group and non-navigated PETD group. In order to quantify the surgeon’s experience, two independent researchers retrospectively performed the radiographic measurements, including posterior and anterior disc space, illiolumbar angle, transverse process area, foraminal area and interlaminar area. Other data such as gender, age, LDH type, LDH location, operation time, exposure time, hospital stay, and complications were also compared and analyzed. In addition, preoperative and postoperative leg and back Visual Analogue Score, Oswestry Disability Index and Japanese Orthopedic Association scores were compared and analyzed. The patients’ satisfaction was assessed by MacNab criteria.

Results:

The intergroup consistency of all radiographic measurements was reliable (I2>0.7, p<0.05). There were more patients with high iliac crest were in PEID group and navigated PETD groups (p<0.001). More upper high-grade migrated cases (7/20) were in navigated PETD groups (p=0.02). There were significant difference in foraminotomy/laminectomy among PEID group (10/25), non-navigated PETD groups (23/27), and navigated PETD groups (20/20) (p<0.001). There were significant differences in illiolumbar angle (p=0.01), transverse process area (p<0.001), and foraminal area (p=0.008) among the three groups. There were no significant differences in gender, age, disc space, disc location, disc type, and laminar area among these groups (P>0.05). Improvements in back and leg pain, as well as complications were similar among these groups.

Conclusions:

PETD is non-inferior to PEID for L5/S1 LDH cases, even for those with high illiac crest, large facet joint, narrow foramen, and small disc space, where foraminotomy and navigation were usually adopted.