Efficacy Comparison of Arthroscopic-assisted Uniportal Spinal Surgery and Percutaneous Endoscopic Discectomy for Adjacent Segment Lumbar Disc Herniation After Fusion Surgery

Consent for publication Not Applicable

Conflict of interest statement

Running title: Surgery for LDH after LF

The authors declare that the study was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Ethical Review Committee Statement

Funding

Declarations

of data availability

The datasets generated during the current study are not publicly available due the rules and regulations and respect the privacy rights of patients, but are available from the corresponding author on reasonable request.

Abstract

Background

Adjacent segment lumbar disc herniation (ASLDH), a recognized complication following lumbar fusion (LF) surgeries, can be managed with various techniques; however, evidence supporting the arthroscopic-assisted uniportal spinal surgery (AUSS) technique for adjacent segment LDH is currently lacking.

Objective

To explore the application and validate the safety and efficacy of Arthroscopic-assisted Uniportal Spinal Surgery (AUSS) in the treatment of adjacent segment LDH.

Methods

One hundred and twelve patients diagnosed with ASLDH were enrolled from 2018 to 2024. Fifty-five patients underwent the AUSS technique, comprising the AUSS group, and fifty-seven patients received percutaneous endoscopic lumbar discectomy (PELD), comprising the PELD group. Perioperative indicators, including 6-month postoperative efficacy rate, postoperative complications, Visual Analogue Scale (VAS), Japanese Orthopaedic Association (JOA) scores, Oswestry Disability Index (ODI), and Short Form-36 Survey Scale (SF-36), were recorded and compared between the two groups at each follow-up time point.

Results

Compared with PELD, AUSS demonstrated a shorter operation time and hospital stay, as well as less blood loss (P < 0.001). The overall efficacy rate in the AUSS group (98.2%) was higher than that in the PELD group (86.0%, P < 0.05) at 6 months postoperatively, and the total incidence of postoperative complications in the AUSS group (3.6%) was lower than that in the PELD group (28.1%, P < 0.001). At each follow-up time point, indicators of serum pain mediators, VAS-Back Pain (VAS-BP), VAS-Leg Pain (VAS-LP), JOA and ODI scores, and each dimension of SF-36 in the AUSS group were superior to those in the PELD group (P < 0.001).

Conclusion

Both the AUSS technique and PELD represent viable surgical options for ASLDH following LF. However, AUSS demonstrates significantly superior functional recovery rates and a lower incidence of procedure-related complications, supporting its broader clinical application.

Key words:

Fusion

lumbar disc herniation

arthroscopic-assisted uniportal spinal surgery

percutaneous endoscopic lumbar discectomy

Introduction

Adjacent segment lumbar disc herniation (ASLDH)[1], a progressively radiographical and symptomatic lumbar disc degeneration adjacent to the previously operated spinal segment, represents a well-documented complication of lumbar fusion (LF) surgery, with a reported incidence ranging from 5.2% to 18.5%[2]. While previous studies have identified numerous risk factors associated with the development and progression of adjacent segment disc degeneration, a clear consensus on its pathogenesis remains elusive[3,4,5]. In addition to causing significant neurofunctional impairments, symptomatic ASLDH detrimentally impacts mental and psychological health and substantially reduces patients' quality of life[6,7]. Therefore, it is imperative to highlight this concern and explore effective preventive and therapeutic measures for ASLDH.

Surgical intervention becomes necessary for ASLDH when conservative management fails[8], and both repeated open fusion (FIGURE 1) procedures and minimally invasive spine surgery (MISS) techniques can achieve adequate neural decompression[9–12]. Established and conventional open spinal fusion techniques, including posterior lumbar interbody fusion (PLIF), posterior laminectomy with fusion (PLF), oblique lumbar interbody fusion (OLIF), and anterior lumbar interbody fusion (ALIF), are employed in the treatment of ASLDH. However, it cannot be denied that open fusion techniques induce a second painful experience and substantial trauma to the muscle tissue, and revision surgeries do not consistently yield satisfactory clinical outcomes, potentially diminishing patient satisfaction. In contrast, MISS has emerged and gained preference as a preferred method for ASLDH due to its minimal incision, which mitigates damage to facet joints and posterior ligaments, and results in less muscle tissue injury[13]. Furthermore, MISS techniques have been widely used for their lower incidences of perioperative complications, such as nerve root injury and dural tear, which is particularly advantageous in the setting of pre-existing surgical scars and instrumentation[11,12]. Thus, MISS techniques appear to have more advantages compared with open repeated operations in treating ASLDH.

Further developments in endoscopic spinal surgeries provide various options for lumbar disc herniation (LDH). As an alternative solution and a key component of MISS techniques, percutaneous endoscopic lumbar discectomy (PELD) has been widely recognized for encouraging results and is accepted for various presentations of LDH, including ASLDH. In addition, as a uniportal, non-coaxial spinal endoscopic surgery (UNSES), arthroscopic-assisted uniportal spinal surgery (AUSS) aligns with the principles of open surgery and offers outstanding advantages in instrument channel design, enhancing endoscopic visualization and operational flexibility[14,15]. Crucially, the integration of a 30° arthroscope provides a wider field of view and compatibility with various spinal surgical techniques and instruments. Therefore, the superior maneuverability suggests broader applicability for degenerative disc conditions compared to coaxial systems like PELD for ASLDH. Thus, this study aimed to compare the safety and efficacy of these two prominent MISS techniques—PELD and AUSS—in the treatment of ASLDH following LF. We retrospectively analyzed clinical data from 112 consecutive ASLDH patients who underwent either PELD or AUSS.

Materials and Methods

Participants

The study was approved by the authors’ institutional review board.

All surgeries described in this study were approved by the ethics committee of our institution. In addition, the study has been reported in line with the STROCSS criteria.

ASLDH was predominantly diagnosed via symptoms, signs, and imaging findings in the department of spine surgery from 2018 to 2024. The inclusion criteria for the study were as follows: (I) patients who had undergone LF surgery and had a diagnosis of ASLDH confirmed by X-rays, CT, and MRI; (II) patients who underwent the AUSS technique or PELD surgery; (III) patients with a follow-up period longer than 12 months and complete clinical and follow-up data. The exclusion criteria were: (I) patients with other causes (e.g., osteoporosis, lumbar instability, fractures, spinal tumors, or inflammatory spinal conditions) leading to low back pain and leg pain; (II) patients with severe comorbidities (such as pneumopathy or cardiovascular or cerebrovascular disease) who could not tolerate general anesthesia; (III) patients with mental and psychological disorders who could not comply with regular follow-up.

Methods

All surgical interventions were carried out by a single senior spinal surgeon with extensive experience.

AUSS Group

The AUSS procedures were conducted under general anesthesia. Patients were placed in a prone position on a carbon fiber radiolucent operating table. Abdominal suspension was employed to decrease intra-abdominal pressure and limit surgical blood loss. The target spinal level was initially approximated using superficial anatomical landmarks and subsequently confirmed precisely under real-time C-arm fluoroscopic guidance by inserting a Kirschner wire into the intended intervertebral space. A longitudinal skin incision, measuring about 1.5–1.8 cm, was created adjacent to the pedicles at the midline, carefully dissecting through the skin, subcutaneous tissue, and lumbar dorsal fascia. The arthroscope, coupled with the working sheath, was introduced alongside connections for the light source, motorized drill, radiofrequency ablator, and continuous saline irrigation, thereby exposing the facet joint's articular capsule. Radiofrequency ablation ensured local hemostasis, and a rongeur was utilized to clear and expose the articular capsule. Bony decompression was performed with a high-speed drill, following a predetermined circular trajectory (FIGURE 2) that involved: 1) the spinous process base and inferior lamina of the cranial vertebra; 2) the facet joint process; and 3) the spinous process base and superior lamina of the caudal vertebra. The decompression zone provided visualization of the superior articular process, ligamentum flavum, nerve root, and intervertebral disc. The nerve root was gently retracted and shielded, after which the annulus fibrosus was opened using a miniature blade. Herniated nucleus pulposus material was meticulously extracted with specialized forceps. Successful decompression was indicated by a relaxed, non-tensioned nerve root. Finally, radiofrequency ablation was applied to thermally coagulate the annulus fibrosus, aiming to minimize recurrence risk. Endoscopic inspection reaffirmed nerve root relaxation. The endoscope was then withdrawn, a negative-pressure drainage bulb was positioned, the wound was sutured, and a sterile dressing was applied.

PELD Group

Patients in the PELD group were administered general anesthesia and positioned prone. The affected spinal segment was localized and marked under C-arm fluoroscopy. An initial puncture was made roughly 10 cm from the midline, directed through the intervertebral foramen towards the pathological site. C-arm imaging confirmed accurate needle placement. A minor skin incision allowed insertion of a guidewire, followed by sequential dilators to accomplish foraminoplasty. An endoscopic system designed for the intervertebral foramen was then introduced. Under direct endoscopic vision, hemostasis was secured via electrocoagulation, and the pathological nucleus pulposus tissue was identified and removed. Confirmation of complete nerve root decompression was obtained. The procedure concluded after verifying restored nerve root pulsation and absence of active bleeding; the endoscope was removed and the incision closed.

Clinical Data and Evaluation

Clinical Indicators

The following parameters were documented and analyzed preoperatively and at 3, 6, and 12 months post-surgery: (1) Pain intensity, evaluated via the Visual Analogue Scale (VAS) for both lower back pain (VAS-BP) and lower limb pain (VAS-LP). (2) Neurological function, gauged using the Japanese Orthopaedic Association (JOA) scoring system. (3) Functional disability, measured by the Oswestry Disability Index (ODI). (4) Quality of life, assessed with the Short Form-36 (SF-36) health survey. (5) Postoperative complications, including nerve root injury, dysesthesia in the affected limb, epidural hematoma, incidental dural tear, hip pain, delayed wound healing, and surgical site infection. (6) Serum pain mediator levels. Fasting venous blood samples (5 mL) were obtained preoperatively and at 3, 6, and 12 months postoperatively. After centrifugation (2500 rpm for 10 minutes, 6 cm radius), serum concentrations of 5-hydroxytryptamine (5-HT), substance P (SP), and norepinephrine (NE) were quantified using enzyme-linked immunosorbent assay (ELISA).

Therapeutic Efficacy Rate

Clinical success at the six-month postoperative mark was determined according to modified MacNab criteria, classifying outcomes as: (1) Excellent: Absence of symptoms, unrestricted return to pre-disease activity levels; (2) Good: Minimal residual symptoms not interfering with daily function; (3) Fair: Moderate symptom improvement but with significant activity limitations; (4) Poor: Little to no improvement or worsening condition. The overall success rate was defined as the proportion of patients with Excellent or Good outcomes relative to the total cohort, serving as the primary measure of surgical efficacy.

Statistical Analysis

Statistical analysis was performed using SPSS version 26.0 (IBM, Armonk, New York, USA), with P < 0.05 considered statistically significant. Continuous data are summarized as mean ± standard deviation. Intergroup comparisons of continuous variables were performed using independent samples t-tests, while intragroup comparisons employed paired samples t-tests. Categorical data, expressed as percentages, were analyzed via the Chi-square test.

Results

Demographics

Patient demographic and baseline characteristics are detailed in Table 1. The two groups were statistically comparable regarding gender distribution, age, and duration of follow-up (P > 0.05). However, the AUSS group exhibited significantly reduced intraoperative blood loss, shorter operative duration, and decreased length of hospital stay compared to the PELD group (P < 0.001).

Table 1

Comparison of demographic data (mean ± SD) between the two groups before surgery.
Group	n	Gender(M/F)	Age(years)	Number of X-ray exposure	Operation time(min)	Blood loss(ml)	Hospital study(day)	Follow-up period(m)
AUSS	55	19/34	66.9 ± 6.3	5.6 ± 0.9	67.3 ± 11.3	72.8 ± 9.8	5.7 ± 1.5	13.8 ± 1.1
PELD	57	25/32	65.9 ± 7.6	2.0 ± 0.6	77.3 ± 15.1	108.8 ± 13.9	6.9 ± 1.0	13.6 ± 0.9
χ²/t		0.734	-0.807	26.732	3.923	15.841	5.073	-1.191
P		0.391	0.421	0.000	0.000	0.000	0.000	0.236

Functional Indicators

The clinical indicators of VAS, JOA, and ODI are compared and exhibited in FIGURES 3–6. At each follow-up time point, the JOA score was higher in the AUSS group than in the PELD group (P < 0.001), while VAS-BP, VAS-LP, and ODI scores were lower in the AUSS group than in the PELD group (P < 0.001).

Quality of Life

The scores of the eight dimensions of the SF-36 at 3, 6, and 12 months postoperatively increased in both groups compared with the preoperative values (P < 0.001). The dimension scores for physical functioning (PF), role limitations due to physical health problems (RP), bodily pain (BP), general health perceptions (GH), vitality (VT), social functioning (SF), role limitations due to emotional problems (RE), and mental health (MH) in the AUSS group were higher than those in the PELD group at each follow-up time point (P < 0.001) (Table 2 − 1,2–2,2–3).

Table 2

− 1 Comparison of life quality between two groups at the same timepoint (mean ± SD)
Group	PF				RP				BP
	Preop	3m postop	6m postop	12m postop	Preop	3m postop	6m postop	12m postop	Preop	3m postop	6m postop	12m postop
AUSS	55.8 ± 5.2	65.1 ± 3.7^***๟๟๟	70.6 ± 3.0^***๟๟๟	75.1 ± 3.4^***๟๟๟	57.3 ± 4.8	67.4 ± 3.6^***๟๟๟	72.1 ± 3.4^***๟๟๟	77.0 ± 3.2^***๟๟๟	42.8 ± 3.7	55.1 ± 3.3^***๟๟๟	60.1 ± 3.5^***๟๟๟	65.1 ± 3.5^***๟๟๟
PELD	55.5 ± 5.6	60.3 ± 3.6^***	65.4 ± 3.0^***	70.3 ± 3.5^***	56.9 ± 4.6	61.8 ± 3.3^***	67.3 ± 3.4^***	71.8 ± 3.3^***	42.2 ± 3.9	48.2 ± 3.2^**	55.3 ± 3.2^***	60.1 ± 3.2^***

Table 2

2 Comparison of life quality between two groups at the same timepoint (mean ± SD)
Group	SF				VT				RE
	Preop	3m postop	6m postop	12m postop	Preop	3m postop	6m postop	12m postop	Preop	3m postop	6m postop	12m postop
AUSS	50.0 ± 3.1	60.2 ± 3.2^***๟๟๟	65.3 ± 3.2^***๟๟๟	70.2 ± 3.1^***๟๟๟	52.3 ± 2.9	62.1 ± 3.3^***๟๟๟	66.7 ± 3.2^***๟๟๟	72.6 ± 3.6^***๟๟๟	46.4 ± 3.6	56.7 ± 3.3^***๟๟๟	60.1 ± 3.3^***๟๟๟	64.2 ± 3.2^***๟๟๟
PELD	50.7 ± 3.3	55.0 ± 3.3^***	60.1 ± 3.3^***	64.8 ± 3.4^***	52.6 ± 3.0	57.1 ± 3.4^***	62.6 ± 3.6^***	67.3 ± 3.4^***	46.1 ± 3.8	51.1 ± 3.5^**	56.0 ± 3.4^***	60.4 ± 3.5^***

Table 2

2 Comparison of life quality between two groups at the same timepoint (mean ± SD)
Group	SF				VT				RE
	Preop	3m postop	6m postop	12m postop	Preop	3m postop	6m postop	12m postop	Preop	3m postop	6m postop	12m postop
AUSS	50.0 ± 3.1	60.2 ± 3.2^***๟๟๟	65.3 ± 3.2^***๟๟๟	70.2 ± 3.1^***๟๟๟	52.3 ± 2.9	62.1 ± 3.3^***๟๟๟	66.7 ± 3.2^***๟๟๟	72.6 ± 3.6^***๟๟๟	46.4 ± 3.6	56.7 ± 3.3^***๟๟๟	60.1 ± 3.3^***๟๟๟	64.2 ± 3.2^***๟๟๟
PELD	50.7 ± 3.3	55.0 ± 3.3^***	60.1 ± 3.3^***	64.8 ± 3.4^***	52.6 ± 3.0	57.1 ± 3.4^***	62.6 ± 3.6^***	67.3 ± 3.4^***	46.1 ± 3.8	51.1 ± 3.5^**	56.0 ± 3.4^***	60.4 ± 3.5^***

Serum Pain Mediators

Significant reductions in serum levels of 5-HT, SP, and NE were observed postoperatively in both groups (P < 0.001). Notably, the AUSS group displayed consistently lower concentrations of all three pain mediators compared to the PELD group at the 3-, 6-, and 12-month time points (P < 0.001), detailed in Table 3.

Table 3

Comparison of perioperative serum pain mediators between the two groups (mean ± SD)
Group	5-HT (µmol/ml)				SP (ng/ml)				NE (pg/ml)
	Preop	3m postop	6m postop	12m postop	Preop	3m postop	6m postop	12m postop	Preop	3m postop	6m postop	12m postop
AUSS	0.93 ± 0.18	0.54 ± 0.15^***๟๟๟	0.31 ± 0.9^***๟๟๟	0.18 ± 0.06^***๟๟๟	223.25 ± 28.67	137.66 ± 25.38^***๟๟๟	76.38 ± 13.35^***๟๟๟	33.26 ± 4.75^***๟๟๟	7.33 ± 0.85	3.98 ± 0.63^***๟๟๟	2.78 ± 0.35^***๟๟๟	1.76 ± 0.33^***๟๟๟
PELD	0.91 ± 0.19	0.63 ± 0.12^***	0.39 ± 0.11^***	0.25 ± 0.08^***	221.53 ± 27.55	166.25 ± 28.59^***	102.32 ± 21.56^***	58.48 ± 10.36^***	7.17 ± 0.91	4.75 ± 0.53^***	3.64 ± 0.41^***	2.69 ± 0.51^***
Note: compared with the preoperative period in the same group, ^***P < 0.001; compared with the PELD group in the same period,^๟๟๟P < 0.001.

Operative Success Rate

Based on the modified MacNab criteria, the overall clinical success rate at 6 months was significantly higher in the AUSS group (98.2%) than in the PELD group (86.0%) (P < 0.05), as shown in Table 4.

Table 4

Comparison of surgical efficacy rate at 6 months postoperatively between the two groups n (%)
Group	n	Excellent	good	Fair	Poor	Overall efficacy
AUSS	55	44(80)	10(18.2)	1(1.8)	0(0)	54(98.2)
PELD	57	39(68.4)	10(17.5)	8(14.0)	0(0)	49(86.0)
χ²						5.653
P						0.017

Complications

The incidence of postoperative complications was significantly lower in the AUSS group (3.6%) compared to the PELD group (28.1%) (P < 0.001). Specific complications are itemized in Table 5.

Table 5

Comparison of incidence of postoperative complications between the two groups n (%)
Group	n	Nerve root injury	Dysesthesia in the affected lower limb	Epidural hematoma	Incidental dural tear	Hip pain	Delayed wound healing	Infection	Total incidence
AUSS	55	0(0)	2(3.6)	0(0)	0(0)	0(0)	0(0)	0(0)	2(3.6)
PELD	57	2(3.5)	6(10.5)	0(0)	0(0)	4(7.0)	4(7.0)	0(0)	16(28.1)
χ²									12.389
P									0.000

Discussion

As an increasingly recognized long-term complication following instrumented lumbar fusion surgery, adjacent segment lumbar disc herniation (ASLDH) presents with distinct clinical and imaging features[1,16]. While fundamentally rooted in disc degeneration, ASLDH pathogenesis is multifactorial, involving physiological aging, biomechanical alterations secondary to fusion, iatrogenic factors during the index surgery, and patient-specific variables[9,17]. Numerous investigations have illustrated that the incidence of ASLDH progressively increases over time following lumbar fusion surgeries[17,18]. Multiple factors related to the characteristics of the first operation, including surgical approach, length of fusion, sacral fusion, disrupted integrity of the posterior complex, rigid instrumentation, and pre-existing disc degeneration, contribute to the unique nature of ASLDH[19]. Management of symptomatic ASLDH initially aligns with the principles for lumbar disc herniation. However, controversy arises when conservative measures fail, necessitating surgical intervention, and the therapeutic crossroads stems directly from the inherent complexity of ASLDH[11,20]. Therefore, the interplay of diverse causative factors, encompassing etiology and pathological characteristics, collectively contributes to the ongoing debate regarding the optimal surgical strategy for revision ASLDH surgery.

Various surgical methods contribute their advantages to promote neurofunctional recovery for ASLDH[21–23]. Conventional open operative management with instrumentation can provide direct and complete decompression of the nerve root, reconstruct spinal alignment and stability, and potentially achieve favorable clinical outcomes. However, repeated open surgeries carry significant risks of perioperative complications and impose a profound physical and psychological burden. Consequently, to avoid or mitigate repeat operation-related trauma, secondary musculoskeletal injury, and potential nerve root or dural injury, spinal endoscopic techniques have rapidly emerged as predominant minimally invasive solutions.

Chen HC et al[24]reported that the PELD method provided complete decompression and had overwhelming superiority over repeated open lumbar surgery in the surgical treatment of ASLDH. Similarly, the AUSS technique can effectively achieve nucleus pulposus removal for nerve root decompression, avoid secondary damage to the posterior and paraspinal structures, preserve the facet joints, and relieve the patient's impaired neurological function, as does PELD surgery. Accordingly, the two techniques are unquestionably applicable to the surgical treatment of ASLDH.

Compared with open revision, both the AUSS technique and the PELD approach align with the primary principles of minimally invasive surgery. AUSS offers specific technical advantages, minimizing instrument interference through its single-portal design and stable intraoperative approach[13]. Furthermore, the 30° arthroscope provides a 360° ultra-wide-angle surgical field of view[13,14], and pre-existing internal fixation facilitates more convenient intraoperative localization and less radiation exposure. These features may contribute to a relatively gentler learning curve for less experienced surgeons. In contrast, PELD surgery requires exceptional proficiency in foraminal anatomy and demands experienced imaging navigation skills. Moreover, the PELD procedure carries inherent risks of inaccurate puncture and nerve root injury, which are amplified in the setting of post-surgical epidural adhesions and scar tissue, resulting in a steeper and potentially longer learning curve[14]. Therefore, although the two minimally invasive techniques demonstrate advantages in treating ASLDH, the AUSS technique may be more likely to be adopted and promoted for its safety and maneuverability.

The significant changes in functional indicators demonstrated the efficacy and safety of AUSS and PELD. Patients with ASLDH differ from those with first-time simple lumbar disc degeneration; although they may have similar nerve lesions and functional impairments, ASLDH patients have a greater mental and psychological burden[1]. Consequently, in addition to the indications and contraindications for the operation, factors such as patient preference, acceptance of reoperation, pathological situation, and characteristics of ASLDH must be fully considered before the final surgical decision-making.

Although PELD achieves encouraging results in clinical practice, concerns persist regarding muscle trauma, decompression accuracy and extent, risks of incidental durotomy and cerebrospinal fluid leakage, significant radiation exposure, and reports suggesting relatively higher recurrence rates[25,26]. Comparing PELD surgery for ASLDH, AUSS demonstrates potential superiority across several domains: surgical strategy flexibility, neurofunctional recovery, perioperative complication profile, and quality of life improvement. The enhanced outcomes observed with AUSS may stem from its precise surgical planning, superior visualization via the 30° arthroscope, and greater operational flexibility. Utilizing a single incision for both working and viewing channels, the AUSS technique facilitates wider decompression and higher operability, potentially enabling bilateral decompression through a unilateral approach[27]. This technique maximizes the preservation of lumbar bony structures, thereby enhancing spinal stability and biomechanical properties while simultaneously accelerating functional recovery. Crucially, patient satisfaction is intrinsically linked to neurological recovery and is significantly impacted directly by perioperative complications, particularly symptom recurrence. Hence, the AUSS technique is theoretically superior to that of PELD surgery.

In this investigation, the AUSS group demonstrated better performance in terms of less blood loss and shorter operation time and hospital stay. Improvements in functional outcome measures, including JOA, ODI, and SF-36 scores, were significantly better in both groups. Evidence of high rates of overall clinical efficacy and lower total complication incidences further supports this finding. General serum pain mediators, including 5-HT, SP, and NE, are associated with nociceptive pain effects, and the variation trends of these indicators were parallel to those of the VAS scores in the study. As is known, with the transformation from tension to relaxation of the nerve, pain mediators rise and fall accordingly. This phenomenon indicates that the more sufficient the nerve decompression, the lower the content of pain factors and the pain score will be. However, from horizontal comparisons at identical postoperative time points between the two groups, the PELD group exhibited significantly lower JOA and SF-36 scores, alongside higher ODI and VAS scores, and relatively elevated levels of serum pain mediators. Therefore, a comprehensive cross-comparative analysis and rigorous validation of substantial datasets consistently demonstrate a significant trend towards superior outcomes with the AUSS technique relative to PELD surgery in treating ASLDH.

Nonetheless, there are still some limitations to this study that should be acknowledged. First, the retrospective design and relatively small sample size (n = 112) inherently constrain the generalizability of the findings and introduce potential biases. Consequently, future prospective studies with larger cohorts are essential to validate these results. Second, inherent selection bias exists, as patients were assigned to AUSS or PELD based on pathological characteristics and surgeon assessment, meaning not all patients were candidates for both techniques. Finally, both procedures demand significant technical expertise. AUSS, in particular, requires mastery of incision planning, endoscopic manipulation, and arthroscopic assistance, necessitating a substantial learning curve typically achieved only by experienced spinal surgeons.

Conclusion

Both the AUSS technique and PELD surgery represent effective minimally invasive options for managing ASLDH following lumbar fusion surgery. However, AUSS demonstrates superior outcomes, including significantly improved functional recovery rates, a lower incidence of procedure-related complications, and enhanced patient-reported quality of life. These advantages support the broader clinical application of AUSS for suitable indications. While AUSS demonstrates outstanding advantages in specific situations, prudent surgical decision-making necessitates viewing it as an integrative component within the therapeutic armamentarium, complementing rather than displacing established techniques.

Abbreviations

ASD

adjacent segment disease

LDH

lumbar discs degeneration

lumbar fusion

AUSS

arthroscopic-assisted uni-portal spinal surgery

UNSES

uni-portal non-coaxial spinal endoscopic surgery

PELD

percutaneous endoscopic lumbar discectomy

PLIF

posterior lumbar interbody fusion

PLF

posterior laminectomy with fusion

OLIF

oblique lumbar interbody fusion

ALIF

anterior lumbar interbody fusion

MISS

minimally invasive spine surgeries

JOA

Japanese Orthopedic Association

VAS

Visual Analog Scale

ODI

Oswestry Disability Index

SF-36

Short Form-36 Survey Scale

Fig. 3.6

Indicators comparison of preoperative, 3 month, 6 month and12 month postoperatively (

$\:\stackrel{-}{X}\pm\:s$

). Note: Compared with the preoperative period in the same group, ^***P<0.001; compared with the PELD group in the same period, ^###P < 0.001.

Electronic Supplementary Material

Below is the link to the electronic supplementary material

Supplementary Material 1

Author Contribution

Conceptualization：Tao Liu, Zhimin He, Desheng Wu. Data curation: Tao Liu, Zhongzheng Zhi，Jian Kang. Formal analysis: Tao Liu, Zhongzheng Zhi. Funding acquisition: Zhimin He, Jinhao Miao. Investigation: Tao Liu, Zhongzheng Zhi. Methodology: Tao Liu, Zhimin He. Project administration: Jinhao Miao, Desheng Wu. Resources: Tao Liu, Zhimin He. Software: Tao Liu. Supervision: Zhimin He, Jinhao Miao. Validation: Jinhao Miao, Zhimin He, Shuqiang Wang. Visualization: Zhimin He, Jinhao Miao. Writing-original draft: Tao Liu. Writing- review & editing: Tao Liu, Zhimin He.

Data Availability

References

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