A Suture Technique for Ruptured Annulus Fibrosus Following Decompression Under Percutaneous Transforaminal Endoscopic Discectomy

Summary

This protocol describes an innovative suture technique for ruptured annular fibrosus during percutaneous transforaminal endoscopic discectomy.

Abstract

The suture technique for a ruptured annulus fibrosus (AF) under full-endoscopy remains challenging. Direct suturing of a ruptured annular tear after full decompression has been shown to decrease the recurrence rate of lumbar disc herniation during endoscopic surgery. Traditional suture operations under endoscopy involve only simple suturing of the ruptured AF. Due to the weak and poor quality of the AF tissue around the tear portal, using this area as needle insertion points during suturing may lead to insufficient tension and a low success rate of AF closure. Currently, there is no detailed technical illustration based on video for AF tear suturing under lumbar full-endoscopy. We innovatively propose a method of covering and suturing the AF tear by pulling up the posterior longitudinal ligament (PLL) under lumbar endoscopy and using three stitches (PLL-AF suture technique). The patient who received the novel suture technique achieved satisfactory results. Six months after the operation, lumbar MRI showed no evidence of recurrence in the outpatient clinic.

Introduction

Percutaneous transforaminal endoscopic discectomy (PETD), a minimally invasive procedure used to remove herniated discs in the lumbar spine, is performed with an endoscope – a thin tube with a camera and light at the tip that enables the surgeon to visualize internal tissues and surrounding structures on a monitor¹. With real-time image guidance on the monitor, surgeons can perform positioning, puncture, and placement of the cannula² through a small skin incision of approximately 1 cm. Step-by-step exposure under the endoscope follows, including the removal of surrounding soft tissue and foraminoplasty to enlarge the opening of the targeted lumbar foramen. Once a clear view and sufficient operating space are achieved, complete decompression of the lumbar nerve is performed by removing the compressive fragments³.

Preventing postoperative recurrence of disc herniation remains a long-term concern for spine surgeons. One strategy during surgery to minimize the risk of recurrence is to remove all suspected detached nucleus pulposus (NP), even if it has not yet herniated into the canal. This is because a ruptured annulus fibrosus (AF) cannot be fully repaired, and as a result, detached NP tissue susceptible to intradiscal pressure may potentially reherniate in the future⁴.

Despite promising advancements in tissue engineering for repairing and regenerating the nucleus pulposus (NP) and annulus fibrosus (AF), none of them have been clinically proven effective⁵. The direct closure of the AF tear after full decompression is an important technique for reducing the risk of recurrence in lumbar disc herniation (LDH). Currently, the most frequently used suture technique for AF repair under endoscopy involves performing a simple suture with one single stitch at the site of the tear⁶. Apart from concerns about whether a single stitch can generate enough tension, an insufficient suture area (both in terms of quality and quantity) on both sides of the annular tear is frequently encountered after endoscopic decompression.

Therefore, this study proposes a new technique for suturing the AF after decompression of PETD by pulling and suturing the nearby posterior longitudinal ligament (PLL) over the AF tear with three stitches (PLL-AF suture technique).

Protocol

The protocol adheres to the regulations stipulated by the ethical committee of Huazhong University of Science and Technology Union Shenzhen Hospital, which has granted approval for the protocol. The written informed consent from the patient was obtained. A 31-year-old female patient was enrolled, who had suffered from consistent left leg radiating pain with a visual analogue scale (VAS)7 equal to 8. Physical examination findings were as follows: (1) upper body side bending to the right; (2) restri…

Representative Results

After successful and sufficient decompression, the herniated disc at L4/5 (Figure 2A,A') was resected. Local AF tear (both medial and lateral tear edges) and PLL were identified under the endoscope. The first stitch ensured that the lateral tear edge was contained and sutured. The PLL and the medial AF tear edge were penetrated and stitched along with the first stitch. A third fastened stitch was tied with the second stitch at the cranial side of the first stitch. The ke…

Discussion

Achieving excellent AF suturing under the endoscope has significant benefits. It is expected to reduce the nerve mechanical stimulation caused by AF rupture or bulge, thereby decreasing postoperative residual discogenic low back pain and/or sciatica pain^4,12. Closing the annular tear portal can reduce nerve root irritation caused by the release of inflammatory mediators from the intervertebral disc⁵. Additionally, patients can feel more co…

Materials

0.5% lidocaine	Beijing Tide Pharmaceutical Co., Ltd	H37022768	For postoperative pain
Dilatation cannula	Beijing Tianqi Medical technology Co., Ltd., Beijing	ZJ289019	Cannulation
Disposable annular stapler	Medical Science & Technology Co., Ltd., Beijing	SMILE-L, 2020	Suture
Disposable stitches	Medical Science & Technology Co., Ltd., Beijing	SMILE-L, 2020-022	Stitch
Flurbiprofen axetil	Shandong Hualu Pharmaceutical Co., Ltd.	H20041508	For postoperative pain
Puncture needle	Beijing Tianqi Medical technology Co., Ltd., Beijing	ZJ289033	Puncture
Trephine saws	Beijing Tianqi Medical technology Co., Ltd., Beijing	ZJ289036	Foraminoplasty