Microendoscopic Discectomy for Far Lateral Lumbar Disk Herniation

To examine the clinical results of different minimally invasive techniques for the therapy of far lateral disc herniation in middle-aged and elderly patients. An endoscopic approach (percutaneous endoscopic lumbar discectomy; PELD), MIS-TLIF combined with contralateral translaminar screw (MIS-TLIF CTS), and MIS-TLIF combined with bilateral pedicle screws (MIS-TLIF BPS) were evaluated via a retrospective chart review. Data from 74 consecutive middle-aged and elderly patients with far lateral disc herniation were analyzed. All patients underwent surgery; 19 with PELD, 24 with MIS-TLIF CTS, and 31 with MIS-TLIF BPS. Clinical data included the length of the incision, duration of the operation, estimated blood loss, hospitalization time, operation cost, recurrence rate, and fusion rate. Preoperative and postoperative patient outcomes including the VAS, ODI scores and MacNab criteria were assessed and recorded. The mean follow-up time was 26.4 months (range from 14 to 46 months). Compared with the internal fixation groups, the length of the incision, duration of operation, estimated blood loss, and hospitalization time were obviously lower in the PELD group. The difference in operation cost among the three methods was statistically significant. The postoperative VAS scores for LBP and LP decreased significantly as compared with those recorded preoperatively. The postoperative ODI scores were lower than those recorded preoperatively. MacNab criteria rating excellent, good and fair results were in 27, 37 and 10 patients, respectively. Conclusion: PELD, MIS-TLIF CTS, and MIS-TLIF BPS are all effective minimally invasive techniques for the therapy of single segment far lateral lumbar disc herniation in middle-aged and elderly patients. PELD had a shorter operation time and less surgical trauma, being a less invasive and more economical method; however, there was no recurrence of disc herniation after fixation. Compared with MIS-TLIF BPS, MIS-TLIF CTS obtained a similar clinical effect and certain costs were saved.

To introduce the METRx microendoscopes diskectomy system in the treatment of far lateral lumbar disc herniation. Fourteen cases of far lateral lumbar disc herniation were operated with METRx from February 1999 to December 2002. Among them, the average age was 49 years old (range 41 - 55 years old), male in 10 cases, female in 4 cases. All cases were single disc herniation; L(4), 5 herniation in 6 discs, L(5)-S(1) herniation in 8 discs; foraminal disc herniation in 6 cases, extra-foraminal disc herniation in 8 cases. All the cases were followed up from 12 to 46 months (average 26.5 months) with the results of excellence in 10 cases, good in 3 cases, fair in 1 case and no failure case. There were no disc infection, dura laceration, nerve root injury and herniation recurrence. METRx is suitable for far lateral lumbar disc herniation with the advantages of minimal invasive, complete decompression of nerve root and rapid recovery. The correct approach and precise surgical technique are the key points for this operation.

This study aimed to evaluate the efficacy of condoliase injection therapy (CIT) for lateral lumbar disc herniation (LLDH). This retrospective study included 157 of 180 enrolled patients (70 males, 87 females; mean age: 52.6±16.9 years). These patients were divided into two groups (group L: LLDH, group M: medial LDH [subligamentous and transligamentous]). From baseline to 1 year after injection (final follow-up), leg pain was assessed using the visual analog scale (VAS) and the Japanese Orthopedic Association (JOA) scoring for CIT's clinical efficacy of CIT. Radiography and magnetic resonance imaging conducted before and 3 months after the injection were assessed. Patients with a VAS improvement of ≥50% at the final follow-up were defined as responders. The responder and nonresponder LLDH groups were also compared. Groups L and M showed comparable responder rates (75.0% and 77.4%, respectively) (P=0.80). VAS and JOA scores at 1 year showed no significant differences between the groups (P=0.82 and 0.80, respectively). VAS score at 1 month after injection reduced considerably in the responder group compared with that in the nonresponder group (19.7 vs. 66.0, P<0.01) and continued to decrease at the last follow-up (3.5 vs. 52.0, P<0.001). Nonresponders had significantly lower disc heights after 3 months. However, intervertebral instability, alignment, and disc degeneration did not differ between the responders and nonresponders. The response rate of CIT for LLDH was comparable to that for medial LDH. Therefore, CIT is an effective treatment for LLDH.

To compare the early clinical efficacy, perioperative parameters, and safety profiles of percutaneous transforaminal endoscopic discectomy (PTED) and unilateral biportal endoscopic (UBE) discectomy in treating single-level far lateral lumbar disc herniation (FLLDH). This retrospective cohort study analyzed 81 patients with FLLDH treated between January 2021 and June 2024. Patients were allocated to the PTED group (n = 38) or the UBE group (n = 43) based on the surgical technique received. Perioperative indicators (operative time, incision length, blood loss, hospital stay) and clinical outcomes-assessed by Visual Analogue Scale (VAS) for back/leg pain and the Oswestry Disability Index (ODI) preoperatively and at 1, 3, 6, and 12 months postoperatively-were compared. Statistical analyses included independent samples t-tests, chi-square tests, and repeated-measures ANOVA. All patients completed 12-month follow-up. The two groups were comparable at baseline (P > 0.05). The PTED group demonstrated significantly shorter operative time (62.4 ± 8.7 vs. 105.3 ± 14.1 min, P < 0.001), smaller incision length (7.8 ± 0.9 vs. 24.6 ± 4.2 mm, P < 0.001), less intraoperative blood loss (18.5 ± 4.3 vs. 68.2 ± 10.5 mL, P < 0.001), and shorter hospital stay (4.8 ± 1.1 vs. 5.9 ± 1.7 days, P = 0.002). Both groups showed significant and sustained improvement in VAS and ODI scores postoperatively (P < 0.05). At 1 month, PTED was associated with lower back pain VAS but slightly higher leg pain VAS and ODI compared to UBE (P < 0.05). From 3 months onward, no significant inter-group differences were observed in any clinical scores (P > 0.05). Repeated-measures ANOVA indicated a different improvement trajectory for back pain between the groups (interaction P = 0.024). Both PTED and UBE are effective minimally invasive techniques for FLLDH, offering comparable and excellent mid-term clinical outcomes. PTED offers advantages in reduced surgical trauma and faster early recovery, whereas UBE provides superior endoscopic visualization. The choice of technique can be individualized based on patient characteristics and surgical expertise.

<title>Abstract</title> Purpose To systematically compare the clinical outcomes and learning curves of unilateral biportal endoscopy (UBE) and percutaneous endoscopic lumbar discectomy (PELD) in the treatment of far lateral lumbar disc herniation (FLLDH). Methods A retrospective analysis was conducted on 122 patients with FLLDH who underwent spinal endoscopic surgery between January 2022 and July 2024, including 62 cases in the PELD group and 60 cases in the UBE group. All procedures were performed by the same minimally invasive spine surgery team. Perioperative parameters (operative time, intraoperative blood loss, foraminal area, postoperative hospital stay, total cost), visual analogue scale (VAS) scores, Oswestry Disability Index (ODI), and modified Macnab criteria were compared. Learning curves were analyzed using cumulative sum (CUSUM) with operative time as the core variable. All patients were followed for at least 12 months. Results Baseline characteristics were comparable between groups ( <italic>P</italic> &gt; 0.05). Both PELD and UBE significantly improved lumbar and leg pain ( <italic>P</italic> &lt; 0.05). No significant differences were found in VAS or ODI scores between the two groups preoperatively, at 3 months, or at 12 months postoperatively ( <italic>P</italic> &gt; 0.05). Only on postoperative day 1 did the PELD group show a lower VAS back pain score ( <italic>P</italic> &lt; 0.05). The excellent/good rate based on modified Macnab criteria did not differ significantly ( <italic>P</italic> &gt; 0.05). Perioperative indicators, including operative time, intraoperative and hidden blood loss, and total cost, were all significantly more favourable in the PELD group ( <italic>P</italic> &lt; 0.001). No differences were observed in intraoperative fluoroscopy frequency or foraminal cross-sectional area ( <italic>P</italic> &gt; 0.05). CUSUM analysis indicated that proficiency was achieved after 24 UBE cases and 38 PELD cases. All complications resolved with conservative treatment. Conclusion Both UBE and PELD are safe and effective for treating FLLDH. PELD offers advantages in perioperative minimally invasive characteristics and cost-efficacy, whereas UBE features a shorter learning curve, facilitating more rapid surgical mastery.

Lateral disc herniation (foraminal and extra foraminal) has clinical characteristics that are different from those of medial disc herniation (central and subarticular), including older age, more frequent radicular pain, and neurologic deficits. This is supposedly because lateral disc herniation mechanically irritates or compresses the exiting nerve root or dorsal root ganglion inside of a narrow canal more directly than medial disc herniation. The purpose of this study was to investigate clinical and radiological characteristics of lateral disc herniation in comparison with medial disc herniation. The 352 subjects diagnosed with localized lumbosacral disc herniation and followed up for at least 12 months after completion of treatment were included and divided into medial and lateral disc herniation groups, according to the anatomical location of the herniated disc in axial plain of magnetic resonance image. Clinical and radiological data were obtained and compared between the two groups. The lateral group included 74 (21%) patients and the medial group included 278 (79%). Mean age of the lateral group was significantly higher than that in the medial group. The lateral group showed a significantly larger proportion of patients with radiating leg pain and multiple levels of disc herniations than the medial group. No significant differences were found in terms of gender, duration of pain, pretreatment numeric rating scale, severity of disc herniation (protrusion and extrusion), and presence of weakness in leg muscles. The proportion of patients who underwent surgery was not significantly different between the 2 groups. However, the proportion of patients who accomplished successful pain reduction after treatment was significantly smaller in the lateral than in the medial group. In conclusion, patients with lateral disc herniation were older and had larger proportion of radiating leg pain than those with medial disc herniation. Lateral disc herniation was more associated with multiple disc herniations and worse clinical outcomes after treatment than medial disc herniation.

Background: Far lateral lumbar disc herniation (FLLDH) compresses the nerve root or dorsal ganglion outside the spinal canal at the same level as the herniation, producing severe pain on the anterolateral thigh. The pain is so severe that many patients cannot even walk. The severity of pain is attributed not only to compression, but also some chemical inflammation. Objective: To report a case of FLLDH whose nerve root was depicted during discography.Case report: A 55-year-old-man presented with severe pain from the left buttock to the left anterolateral thigh and leg. Abnormal shadowing suggested left FLLDH at the L5/S1 level on magnetic resonance imaging. During discography, a shadow suggestive of the left fifth lumbar nerve sheath was depicted. Comparing the computed tomography (CT) after discography and CT after rootgraphy, the root sheath-like shadow on discography was confirmed as the nerve root sheath. After nerve root block, pain decreased and the patient was discharged. Conclusions: The combination of mechanical compression and chemical inflammation by the herniated nucleus pulposus is considered responsible for severe pain in the disc herniation and also in FLLDH. Depiction of the nerve root during discography of FLLDH means that a connection exists between the herniated nucleus pulposus and affected nerve root sheath. Inflammation around the extruded nucleus pulposus penetrates the contacted nerve root sheath; this inflammation is thought to be one of the causes of severe pain in FLLDH. We recommend conservative therapies such as intradiscal or foraminal injection of local anesthetics with steroid for patients with radicular symptoms of FLLDH.

Extraforaminal disc herniations represent up to 11% of all lumbar herniated discs. Numerous surgical approaches have been described. Percutaneous endoscopic discectomy (PED) is one of the minimally invasive techniques; after mastering this procedure it is a practical method that is used for treatment of foraminal or extraforaminal disc herniation. The outcome of PED for treatment of foraminal or extraforaminal disc herniation has been studied. A total of 66 patients with foraminal or extraforaminal lumbar disc herniation was treated by applying the PED technique between January 1998 and June 2005. The positions of the herniated disc levels were L2-3 (n=5, 8%), L3-4 (n=19, 28%) and L4-5 (n=42; 64%). The selected patients had no previous surgery, appropriate conservative therapies were done before the operations, and MRI was the main diagnostic method with the clinical findings. Evaluation of the patients with clinical examinations, visual analogue pain scale (VAS) and Oswestry scale was performed preoperatively, on postoperative day 7 and in the postoperative 6-12 months period. In two patients (n=1, L4-5 and n=1, L3-4) disc material could not be removed with PED, so discectomy was performed with microscopic visualization during the same session. Three patients (n=3, L4-5) were reoperated on three to six months after primary surgery due to recurring disc problems with microscope visualization. In two patients (n=2, L4-5) root nerves were partially damaged, and in two patients (n=2, L4-5) root nerves were impinged by the working channel. These 4 patients had dysesthesias from just after surgery to a mean of 45 days after surgery. One of recurrent cases was among these patients. Neurological examinations showed minimal muscle weakness of the quadriceps femoris and diminished sensation of the L4 dermatomal area in patients with partial nerve root damage. This patient improved and the neurologic examination became normal with disappearance of the dysesthesia. There was no sign of reflex sympathetic dystrophy (RDS). With these two patients VAS and Oswestry scales scores decreased significantly early in the postoperative follow-up. The postoperative 6-month average scores are favourable in comparison with the average score at postoperative day 7. The postoperative 12-month scores showed no significant differences to those of postoperative month 1. Percutaneous endoscopic discectomy is a minimally invasive method and offers many benefits to the patient, but extensive surgical practice is needed to become a capable surgeon. Consequently this technique can only be a treatment option on appropriate patients. This study reconfirmed that the removal of fragmented disc material is achieved and offers a pain-free status.

Background Percutaneous endoscopic lumbar discectomy (PELD) is effective for far lateral lumbar disk herniation (FLLDH), requiring precise puncture. This study assessed 3D reconstruction combined with body-surface meshing for preoperative planning. Methods This prospective randomized controlled trial enrolled 53 FLLDH patients (L4-5/L5-S1) from 2023 to 2024, who were randomized to Group A (n = 29; CT-based 3D-planning with surface grids) or Group B (n = 24; conventional X-ray planning). Outcomes included puncture time, operative time, fluoroscopy frequency, and Oswestry Dysfunction Index (ODI). Results Baseline data were comparable (p > .05). Group A showed shorter puncture time (7.7 ± 2.1 min, 95% CI: 6.9–8.5 vs. 10.5 ± 3.8 min, 95% CI: 9.0–12.0), reduced operative time (48.7 ± 7.2 min, 95% CI: 46.2–51.2 vs. 55.2 ± 10.3 min, 95% CI: 51.0–59.4), and fewer fluoroscopy exposures (5.1 ± 1.9, 95% CI: 4.4–5.8 vs. 14.8 ± 3.9, 95% CI: 13.3–16.3; all p < .05). Both groups had improved ODI/VAS postoperatively (p < .05), with no intergroup clinical difference (p > .05). Conclusions 3D reconstruction enhances puncture precision and reduces intraoperative fluoroscopy reduction in FLLDH-PELD, with clinical outcomes comparable to those of conventional methods.

ObjectivesThis study aims to investigate the clinical efficacy of managing far lateral lumbar disc herniation (FLLDH) through two surgical approaches: unilateral biportal endoscopy (UBE) and percutaneous endoscopic lumbar discectomy (PELD).Patients and methodsBetween December 2019 and September 2024, a total of 45 patients (18 males, 27 females; mean age: 59.76±11.82 years; range, 31 to 89 years) who were diagnosed with FLLDH were retrospectively analyzed. Based on the surgical technique used, the patients were randomly divided into two groups: the PELD group (n=17) and the UBE group (n=28). Perioperative indicators, including operative time, postoperative hospital stay and mean fluoroscopy times, were recorded. Pre- and postoperative assessments were conducted at the time of admission and at one, three, and six months after surgery, using the Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI) scores. The modified MacNab criteria were used to assess patient satisfaction.ResultsBoth groups demonstrated a reduction in VAS and ODI scores after surgery (p<0.05). However, no statistically significant differences were observed between the groups at one, three, or six months postoperatively. Operative times were also comparable, with the UBE group mean 97.39±26.78 min and the PELD group 88.18±27.52 min. The postoperative length of hospital stay was similar, with the UBE group staying a mean of 3.93±1.81 days and the PELD group 3.06±1.21 days (p>0.05). The mean fluoroscopy times were significantly lower in the UBE group, with 6.25±1.30 times compared to 16.76±6.02 times in the PELD group (p<0.05).ConclusionOur study results suggest that UBE is a viable alternative to PELD for treating FLLDH, offering comparable clinical outcomes with reduced radiation exposure.

Operative techniques for the treatment of extreme lateral lumbar disc herniations (ELLDH) have ranged from an interlaminar approach with subtotal or total facetectomy to an enlarged midline approach and various paraspinal lateral, as well as endoscopic approaches. In contrast to purely endoscopic techniques, use of a working tube together with an operative microscope ("minimally invasive microscopically assisted percutaneous approach") combines the advantages of three-dimensional visual control with the minimal surgical trauma of an endoscopic approach. We present this technique and the clinical results in patients with extreme lateral lumbar disc herniation (ELLDH). In a retrospective case series we analyzed the data of 73 consecutive patients with a disc herniation within or lateral to the intervertebral foramen. All of them were operated on using the surgical microscope after blunt dilatation of the paraspinal muscles and insertion of a tubular retractor system (METRx, Medtronic Sofamor Danek). Fifty-nine patients were included in the follow-up study. Follow-up ranged from 10 to 47 months (mean 30.4) and was evaluated after telephone inquiry by the co-author using the modified MacNab criteria . The results with respect to improvement of preoperative symptoms were excellent in 23 patients (39%), good in 25 patients (42.4%), fair in 8 patients (13.5%) and poor in 3 patients (5.1%). Twenty-four patients had still been working prior to surgery, and 20 returned to work after 4-8 weeks. The paraspinal approach for extreme lateral lumbar disc herniations using the minimally invasive microscopically assisted percutaneous technique is reasonable and safe and thus a good alternative to open surgical procedures.

Endoscopic management of L4-5 rostrally migrated lumbar disc herniation (LDH) poses technical challenges. The aim of this study was to compare the clinical outcomes and safety profiles of percutaneous endoscopic transforaminal discectomy (PETD), percutaneous endoscopic interlaminar discectomy (PEID), and unilateral biportal endoscopic discectomy (UBED) for treating this condition. A retrospective analysis of 81 patients who underwent PETD (n = 19), PEID (n = 36), or UBED (n = 26) from April 2019 to October 2022 at a single center was conducted. Over a 24-month follow-up, clinical evaluations included the visual analog scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopaedic Association (JOA) scores, as well as the modified MacNab criteria. Surgical parameters, facet joint integrity, and paraspinal muscle loss were analyzed. All three groups demonstrated significant postoperative improvement in VAS (low back pain and leg pain), ODI, and JOA scores. The UBED group had higher VAS scores for incision pain compared with the other two groups. Within 1 week after the procedure, both the PEID and UBED groups had lower VAS scores for leg pain and higher JOA scores. Notably, the PEID group exhibited the lowest ODI at the 1-week follow-up. At the final follow-up, no significant differences were observed in VAS, ODI, and JOA scores among these groups. No significant differences were observed in modified MacNab evaluation, complication rates, recurrence rates, or the loss ratio of paraspinal muscles. However, PEID and PETD demonstrated advantages in operative time, total incision length, intraoperative blood loss, fluoroscopy injection time, duration of the postoperative hospital stay, total hospitalization expenditure, and serum C-reactive protein and creatine phosphokinase levels. PEID showed optimal performance in preserving the integrity of L4-5 facet joints. PETD, PEID, and UBED demonstrated comparable and satisfactory long-term efficacy in treating rostrally migrated L4-5 LDH over a 2-year follow-up period. PEID emerged as the preferred approach for early postoperative recovery, offering superior preservation of L4-5 facet joint integrity and reduced surgical invasiveness.

Objective To compare the clinical outcomes of minimally invasive transforaminal lumber interbody fusion(MIS-TLIF) and posterior lumbar interbody fusion(PLIF) in obese patients (BMI≥28 kg/m2) with lumbar disk herniation(LDH). Methods A retrospective study of 62 obese patients from January 2009 to March 2014 with LDH was performed at the Third Hospital of Hebei Medical University. According to the surgical approach they underwent, 62 patients were divided into two groups, 32 underwent PLIF, and 30 underwent MIS-TLIF. Before surgery, there were no differences between MIS-TLIF group and PLIF group in terms of the level of serum creatine kinase (CK), visual analogue scale (VAS) scores, Oswestry disability index (ODI) and Japanese Orthopaedic Association (JOA) scores (all P values>0.05). All enrolled patients were followed up for 6 months after operation. The operative time, intraoperative blood loss, postoperative drainage volume and postoperative bedtime were recorded and compared. Meanwhile, the back pain VAS, ODI, JOA scores and serum CK level were also recorded and compared to evaluate the clinical effects. Postoperative complications were also recorded and compared between two groups. Results Compared with PLIF group, the operative time was longer than that in MIS-TLIF group, [(154±54)min vs (103±31)min, t'=4.489, P 0.05). At the 3- and 6- month follow-up, the mean JOA score in MIS-TLIF group was significantly higher than that in PLIF group (all P values<0.01). Three patients with delayed union(one patient had wound infection) in PLIF group, and there were no other complications in both groups. Conclusions Obese patients can achieve good efficacy with MIS-TLIF or PLIF treatment, but MIS-TLIF treatment shows shorter operation time, less trauma and bleeding volume, less incidence of short-term pain, low complication rate and faster postoperative recovery. Key words: Intervertebral disc displacement; Obesity; Surgical procedures, minimally invasive; Spinal fusion; Surgical complication

Microendoscopic discectomy (MED) has been accepted as a minimally invasive procedure for lumbar discectomy because of the small skin incision and short hospital stay required for this surgery. However, there are few objective laboratory data to confirm the reduced systemic responses in the early phase after this procedure. In order to substantiate the reduced invasiveness of MED compared to microdiscectomy (MD) or procedures involved in one-level unilateral laminotomy, the invasiveness of each surgical procedure was evaluated by measuring serum levels of biochemical parameters reflective of a post-operative inflammatory reaction and damage to the paravertebral muscles. Thirty-three patients who underwent lumbar discectomy or one-level unilateral laminotomy (MED in 15 cases, MD in 11 cases and one-level unilateral laminotomy in 7 cases with lumbar spinal canal stenosis) were included in this study. The serum levels of C-reactive protein (CRP) and creatine phosphokinase (CPK) were measured at 24 h after operation. Interleukin-6 (IL-6) and Interleukin-10 (IL-10) were measured at 2, 4, 8 and -24 h following the surgery to monitor the inflammatory response to the respective surgery. The post-operative serum CRP levels from both the MD and MED groups were significantly lower than those from the open laminotomy group. However, there was no significant difference in these serum levels between the MED and MD groups. The levels of IL-6 and IL-10 in the MED group during the first post-operative day were also significantly lower than those in the laminotomy group. When the MED and MD groups were compared, the IL-6 levels in the MED group were lower than in MD group at 2, 4 and 8 h after surgery, but the differences were not statistically significant. However, the level was significantly lower in the MED group at 24 h after surgery. In terms of IL-10, no significant difference was noted between the MED and MD groups over the study period. The changes in serum levels of post-operative inflammatory: markers (CRP, IL-6 and IL-10) in the early phase indicated reduced inflammatory reactions in MED as well as in MD when compared with classical open unilateral laminotomy. These data draw a direct link between the lower level of the inflammatory response and reduced invasiveness of MED. However, an indicator for muscle damage (CPK) appeared not to be affected by the type of surgical procedure used to correct disc herniation.

The microendoscopic discectomy (MED) system for lumbar disc herniation has been developed in recent years. We applied the MED system to the treatment of extraforaminal lumbar disc herniation. The purpose of this Chapter is to present the clinical results of the MED system for cases of extraforaminal lumbar disc herniation. We performed operations using the MED system on eight patients suffering from extraforaminal lumbar disc herniation. The mean age was 57.4 years. Herniation affected discs at the L2-3 (one patient), L3-4 (one patient), L4-5 (two patients), and L5-S1 (four patients) levels. We recorded the operation time, blood loss, and time until the resumption of walking, and used the Japanese Orthopaedic Association (JOA) score for low back pain in evaluating the clinical results. The mean operation time was 90.1 min. The mean blood loss was 12.3g. All patients began to walk within 6 h postoperatively. The mean JOA score improved from a preoperative 8.2 to a postoperative 25.8. There were no complications. The MED system allows treatment of extraforaminal lumbar disc herniation with good visualization, less pain, and early return to daily activity. Our results showed that the MED system is beneficial in the treatment of extraforaminal lumbar disc herniation.