The Comparisons of Surgical Outcomes and Clinical Characteristics between the Far Lateral Lumbar Disc Herniations and the Paramedian Lumbar Disc Herniations

Percutaneous endoscopic lumbar discectomy for extreme lateral lumbar disc herniation

Background

Far lateral disc herniation (FLDH) constitutes a minor portion of the total discectomy workload for spine surgeons. So far, there is still a debate about the term "extreme lateral," and in general, it describes the intra - and extraforaminal position of the disc herniation. We present a surgical treated case series in which the disc herniation on the lumbar spine was still ventral of the exiting nerve root far outside of the foramen.

Methods

Study Design and Patient Characteristics: retrospective analysis of 14 surgical treated patients. Surgical Technique: In all patients, the so-called foraminal retreat maneuver (percutaneous endoscopic lumbar discectomy) was performed. A foraminoscope with a 15° optic orientation and a nonbeveled working sleeve were used in all cases. The aforementioned technique represents a modification of the "inside-out" endoscopic surgery on the lumbar spine.

Results

We treated 11 male and 3 female patients with an average age of 67 years and 66 years, respectively. Except for one, 13 patients presented with clear monoradicular symptoms accompanied by mild-to-moderate neurological deficits. In 11 cases, the disc herniation exhibited cranial migration; two were at the disc level, and in another case, caudal migration was observed. Immediate pain relief and significant improvement of neurological symptoms occurred in all patients. Two patients developed neuropathic pain, which improved after conservative treatment within 6 weeks following the procedure. No recurrence was observed in this case series.

Conclusion

Patients suffering from extreme lateral lumbar disc herniation were found to be significantly older. Furthermore, there is a higher tendency toward male patients and cranial migration of the herniation. The described and modified inside-out technique, along with a 15° optic, allows for clear identification of the exiting nerve root and safe removal of the displaced disc herniation far outside of the spinal canal and foramen. No complications occurred in this small series, and the development of neuropathic pain appears to be relatively common.

Comparing Patient-Reported Outcomes of Lateral to Paramedian Lumbar Disc Herniation: A Propensity Score-Matched Observational Study

OBJECTIVE

To investigate patient-reported outcomes following lumbar discectomy in patients with lateral lumbar disc herniation (LDH) compared with patients with paramedian LDH.

METHODS

Data on patients with lateral and paramedian LDH operated on between 2017 and 2020 at a single public spine unit were extracted from the National Danish Spine Registry, DaneSpine. A propensity score-matched, case-control analysis was conducted to compare the 2 groups. Subgroup analysis was done by further dividing the lateral LDH group into foraminal and extraforaminal groups. Patient demographics, Oswestry Disability Index visual analog scale (VAS) leg and back pain (0-100), EuroQol-5D questionnaire, and measures of patient improvement and satisfaction were collected at baseline and 1 year postoperatively.

RESULTS

Of 887 eligible patients, baseline and 1-year follow-up data were available for 525 patients with paramedian LDH and 68 patients with lateral LDH. Following propensity score matching, the 2 groups were similar in terms of all baseline characteristics (P > 0.05). There were no significant differences between groups in Oswestry Disability Index, VAS leg pain, VAS back pain, and EuroQol-5D 1 year postoperatively. Both groups improved in all outcomes from inclusion to follow-up (P < 0.001). Subgroup analysis showed that patients with foraminal LDH compared with extraforaminal LDH had a significantly greater improvement in VAS leg pain (P = 0.016) with a larger number of patients with clinically significant leg pain improvement (P = 0.03).

CONCLUSIONS

Patients with lateral and paramedian LDH reported similar postsurgical outcomes. Spine surgeons should be less hesitant to operate on patients with lateral LDH. Patients with extraforaminal LDH experienced the least relief of leg pain.

Transforaminal Epidural Injection for Far Lateral Lumbar Disc Herniations: An Alternative to Surgery or Just a Delay?

OBJECTIVE

 Far lateral lumbar disc herniations (FLLDH) are known for causing severe and persistent radicular pain due to direct nerve root and dorsal root ganglion compression. This study evaluates the effectiveness of transforaminal epidural steroid injection (TFSI) in patients with FLLDH, assessing its role as a potential alternative to surgery.

METHODS

 The study retrospectively analyzed 42 patients with radicular pain caused by FLDH, confirmed via lumbar magnetic resonance imaging, who had not benefited from conservative treatment. All patients underwent TFSI, and their pre-treatment Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) scores were compared with scores at one, two, and three months post-procedure.

RESULTS

 The study group comprised 19 males (45.23%) and 23 females (54.77%), with a mean age of 51.9 ± 11.63 years (range 29-76 years). The most common herniation levels were L4-L5 (22 patients), followed by L5-S1 (15 patients) and L3-L4 (five patients). The mean VAS score decreased significantly from 8.58 ± 0.63 to 2.89 ± 1.87 over three months (p = 0.001). Similarly, the mean ODI score significantly reduced from 61.29 ± 6.72 to 16.88 ± 11.25 (p = 0.001). However, eight of the 42 patients (19.04%) underwent surgery within three months due to lack of benefit from TFSI.

CONCLUSION

Our study sheds light on the significant potential of TFSI as a treatment option for FLLDH. The marked improvement in pain and functional capacity, as evidenced by the substantial decrease in VAS and ODI scores, suggests that TFSI can be an effective non-surgical intervention for a majority of patients suffering from FLLDH. However, a notable proportion of patients may still require surgery, indicating that TFSI might not be a definitive alternative but can be an effective interim treatment in managing FLLDH.

Efficacy of epidural steroid injections and evaluation of surgical and anesthetic approaches in far-lateral disc herniations

Aim: To observe the long-term effect of epidural steroid injections (ESI) and describe surgical outcomes in patients with far-lateral lumbar disc herniations. Materials & methods: The medical records of 30 patients who underwent surgery for far-lateral lumbar disc herniations were reviewed. Results: ESI outcomes: pain scores decreased significantly after ESI (p = 0.004). The surgery was delayed for 13.78 ± 8.59 months in patients who received ESI. Surgical outcomes: the improvement in the leg pain was considerably more significant than the back pain (p < 0.001). While motor deficit improved substantially (p < 0.001), there was persistent sensory dysesthesia. Conclusion: ESI does not prevent but may delay the surgery up to 28 months. Although postoperative pain scores were significantly decreased, there was persistent back pain and sensory paresthesia.

Long-term follow-up results of surgically treated patients with foraminal and far lateral disc herniations

PURPOSE

Foraminal and far lateral disc herniations are rarer cause of nerve root compression. There are reports regarding the outcome, however long-term follow-up results of surgically treated patients are few. The purpose of this retrospective study is to analyze the clinical characteristics and long-term surgical outcomes of the foraminal and far lateral disc herniations.

MATERIALS AND METHODS

The 114 patients who underwent an operation for foraminal and far lateral disc herniaitions were reviewed. Visual analogue scale of back and leg pain, the ocurrence of motor deficit and sensory dysesthesia before and after operations were used to compare the results of early and long-term outcome.

RESULTS

A total of 114 telephone interviews were conducted. The mean follow up was 134 months. Complete relief of symptoms were reported by 77 patients (67.1%). The average VAS of radicular leg pain was 7.5 Post-operatively the average VAS of radicular pain decreased to 2.2. Preoperatively, 9 patients (7.6%) had motor deficit and 17 (14.4%) patients had sensory dysesthesia. Post-operatively 9 (100%) of the patients showed motor, and 12 (70.6%) of the patients showed sensory improvement. In 17 patients with hypoesthesia the complaints continued during 2 weeks to 6 months. They were given gabapentin as medical treatment, however 5 of these patients still have sensory dysesthesia. The outcome was: 67.1% excellent (77 patients), 26.3% good (30 patients), 6.1% fair (7 patients).

CONCLUSION

The far lateral approach is a minimally invasive and safe procedure with low complication rates.

Percutaneous Endoscopic Discectomy Via a Transforaminal Approach for L5/S1 Far-Lateral Disc Herniation Assisted by Intraoperative Computed Tomography

OBJECTIVE

To examine the clinical outcomes of a percutaneous lumbar transforaminal endoscopic discectomy (PTED) with intraoperative computed tomography (iCT) navigation for the treatment of L5-S1 far-lateral lumbar disc herniation (LDH).

METHODS

A total of 30 patients with L5-S1 far-lateral LDH who underwent PTED with iCT navigation from September 2016 to October 2020 were enrolled in this study. Outcomes were assessed using the visual analog scale pain score, the Oswestry Disability Index, the Japanese Orthopedic Association score, the EQ-5D-5 L and the modified Macnab criteria. Preoperative and postoperative complications were recorded.

RESULTS

The mean visual analog scale score for leg pain improved from 8.1 at baseline to 2.3, 0.9, 0.7 and 0.9 at 1 day, 1 week, 6 months, and 12 months postoperatively, respectively (P < 0.01). The mean Oswestry Disability Index improved from 78.1% at baseline to 45.5%, 21.9%, 12.6%, and 11.7% at 1 week, 1 month, 6 months, and 12 months postoperatively, respectively (P < 0.01); and the mean Japanese Orthopedic Association score improved from 8.6 at baseline to 14.2, 20.2, 24.4, and 25.6 at 1 day, 1 week, 6 months, and 12 months postoperatively, respectively (P < 0.01). At 12 months postoperatively, the EQ-5D-5 L value significantly increased, from -0.061 ± 0.138 to 0.903 ± 0.064. The rate of a good or excellent modified Macnab result was 93% (26/28) at 12 months postoperatively. In the present study, combined L5-S1 foraminal stenosis tended to lead poor outcomes, which required more postsurgical treatments.

CONCLUSIONS

With iCT navigation, PTED is a feasible and effective minimally invasive surgery for L5-S1 far-lateral LDH.

Clinical experience on intertransverse extraforaminal approach for far lateral disc herniations: 132 cases

Background

Far lateral disc herniations attract many spine surgeons for their type of onset, degree of pain, risk of neurological deficit, and increasing incidence. Today, a direct approach to the region by miminally invasive techniques is preferred.

Aims

We aimed to present the results of the cases that were operated via intertransverse extraforaminal approach through a midline incision.

Patients and Methods

One hundred thirty-two patients who were operated for far lateral disc herniation by extraforaminal approach between January 2010 and December 2017 were retrospectively evaluated. The demographical data, level of disc herniations, examination findings, preoperative and postoperative VAS scores, and postoperative long-term MacNab satisfaction rates were recorded.

Results

Sixty-nine of the patients were male. The mean age was 58.1 years. Acute onset pain was a dominant complaint in 75% of the cases. The mean preoperative VAS score of 8.24 decreased to 2.08 at one month postoperatively. Based on a mean follow-up of 34.4 months, the long-term satisfaction rates according to Macnab criteria were 74% excellent-good, 20% moderate, and 6% poor.

Conclusion

Intertransverse extraforaminal approach is an effective and safe technique for far lateral disc herniations. However, considering the anatomical restrictions and the unfamiliarity of the surgeons with the region, it is important that the surgeons perform the surgery with the technique they know best to increase the success of the surgery.

A Modified Approach for Minimally Invasive Tubular Microdiscectomy for Far Lateral Disc Herniations: Docking at the Caudal Level Transverse Process

Background and Objectives: The use of minimally invasive retractor systems has significantly decreased the amount of tissue dissection and blood loss, and the duration of post-operative recovery after far-lateral disc herniations (FLDH). In this technical note, the technique of docking the tubular retractor on the caudal transverse process is described for an efficient approach with a decreased need for manipulation of the exiting nerve root. Materials and Methods: The case reported is that of a woman affected by a right-sided FLDH at the L4–5 level causing an L4 radiculopathy with weakness and numbness. A review of the literature for FLDH regarding the key anatomy used during a far lateral approach was also performed. Results: The patient showed a significant improvement of her dorsiflexion weakness and radiating leg pain at her 2-week and 5-week post-operative visits, and at a 6-month follow-up she had near-complete relief of her symptoms, including resolution of foot numbness. Prior techniques for tubular microdiscectomy for FLDH report docking on the facet joint, pars interarticularis, and the cranial transverse process. Conclusions: This technical note details that the utility of docking a tubular retractor at the caudal transverse process improves upon already established techniques for minimally invasive tubular discectomy for FLDH.

The irony of the transforaminal approach: A comparative cohort study of transforaminal endoscopic lumbar discectomy for foraminal versus paramedian lumbar disc herniation

Transforaminal endoscopic lumbar discectomy (TELD) is useful for soft lumbar disc herniation (LDH). Although the transforaminal approach can reach the foraminal disc zone, the risk of exiting nerve root irritation along the path is considerable. Few studies have assessed the difficulties of TELD for foraminal LDH. The objective of this study is to compare the clinical results of TELD between foraminal or far-lateral LDH and paramedian LDH.Between June 2016 and July 2017, 135 consecutive patients with single-level LDH were treated with TELD for 2 years. Among them, 25 patients had foraminal or far-lateral LDH (foraminal group), and the remaining 110 patients had central or subarticular LDH (paramedian group). Perioperative data and clinical outcomes were evaluated using the visual analog pain scale, Oswestry Disability Index, and modified Macnab criteria.The foraminal group showed a higher rate of significant access pain (24.00% vs 8.19%, P < .05). The foraminal group also had a longer duration of surgery, length of hospital stay, and return to work (all P < .05). Pain scores and functional status were significantly improved in both groups. Although there were no differences in the outcomes at 2 years postoperatively, early pain and disability at 6 weeks were higher in the foraminal group.Ironically, the early clinical results of TELD for foraminal LDH may be less favorable than those for paramedian LDH. Therefore, great care should be taken during TELD for foraminal or far-lateral LDH.

Five-year outcomes and predictive factors of transforaminal full-endoscopic lumbar discectomy

Although several studies have reported the effectiveness of transforaminal full-endoscopic lumbar discectomy (TELD), no cohort study on the long-term outcomes of TELD has been conducted. Thus, this study aimed to evaluate the long-term clinical outcomes of TELD and to determine the factors predicting favorable outcome.Five-year longitudinal data of 204 consecutive patients who underwent TELD were collected. Outcomes were assessed using the visual analog scale (VAS) pain score, Oswestry disability index (ODI), patient satisfaction rating, and the modified Macnab criteria.The mean VAS score for leg pain improved from 7.64 at the baseline to 1.71, 0.81, 0.90, and 0.99 at postoperative 6 weeks, 1 year, 2 years, and 5 years, respectively (P <.001). The mean ODI improved from 67.2% at the baseline to 15.7%, 8.5%, 9.4%, and 10.1% at postoperative 6 weeks, 1 year, 2 years, and 5 years, respectively (P <.001). The overall patient satisfaction rate was 94.1%. Based on the modified Macnab criteria, 83.8% of patients had excellent or good results. In this study, younger patients with intracanal disc herniation tended to have better outcomes than elderly patients with foraminal/far-lateral disc herniation (P <.05).Transforaminal endoscopic lumbar discectomy offers favorable long-term outcomes with minimal tissue damage. Postoperative pain and functional status may change over time. Proper patient selection remains essential for the success of this minimally invasive procedure.

Clinical and Radiological Characteristics of Lumbosacral Lateral Disc Herniation in Comparison With Those of Medial Disc Herniation

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.

A Modified Approach of Percutaneous Endoscopic Lumbar Discectomy (PELD) for Far Lateral Disc Herniation at L5-S1 with Foot Drop

Foraminal or extraforaminal Far Lateral Disc Herniations (FLDH) extending into or beyond the foraminal zone have been recognized as between 7-12% of all lumbosacral disc herniations. Conventional posterior laminectomy may not provide good access to a herniation that lies far lateral to the lateral margin of the pedicle. Use of the endoscopic technique through a percutaneous approach to treat such FLDH patients can decrease the surgical morbidity while achieving better outcomes. We made an effort to utilize the advantages of percutaneous endoscopic lumbar discectomy (PELD) and to determine the appropriate approach for FLDH at the level between the 5th Lumbar and first Sacral vertebrae(L5-S1). The authors present a case of an endoscopically resected lumbar extruded disc of the left extraforaminal zone with superior foraminal migration at the level of L5-S1, which had led to foot drop, while placing the endoscope in the anterior epidural space without facetectomy.