Extraforaminal Lumbar Disc Herniation Research Articles

Features of Clinical and Magnetic Resonance Imaging of Lumbar Disc Herniation

A study of 55 patients with lumbar disc herniation who were taken MRI and surgery at hospital E from January 2019 to December 2019. Results: The mean age was 58.96 ± 16.4, the female/male ratio was 1.12/1. People doing heavy work had a higher risk of disc herniation than those doing light work (63.7%). Common symptoms: lumbar pain (100%), sciatica pain, pain with mechanical properties (85.45%), limited spinal movement (90.91%), Lasègue sign (+) (74.55%), bell sign (+) (54.55%); signs of nerve root damage: sensory disturbances 72.73%, movement disorders 50.91%. Clinical lesions were common in L5 (65.45%) and S1 (45.45%) roots. Hernias were common at L4/5 (81.8%) and L5/S1 (70.9%). The degree of hernia was mainly bulge and hernia, accounting for 60% and 52.73%, respectively. 98.18% herniated to the back, central hernia accounted for the highest rate (41.82%). The rate of nerve root compression detected on MR is 90.91%. Evaluation of nerve root damage in clinical and magnetic resonance had high concordance in L5 and S1 roots (98.17% and 100%, respectively). Conclusion: MRI helps in early, accurate diagnosis and treatment orientation of lumbar disc herniation.
 Keywords: Disc herniation, MRI lumbar spine, lumbar pain. 
 References
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 (in Vietnamese).[6] J. D. Lurie, T. D. Tosteson, A. N. Tostenson et al., Surgical Versus Non-operative Treatment for Lumbar Disc Herniation: Eight-year Results for the Spine Patient Outcomes Research Trial, Spine, Vol. 39, No. 1, 2014, pp. 3-16, https://dx.doi.org/10.1097%2FBRS.0000000000000088.[7] M. R. Konieczny, R. Jeremia, M. Post et al., Signal Intensity of Lumbar Disc Herniations: Correlation With Age of Herniation for Extrusion, Protrusion, and Sequestration, Int J Spine Surg. Vol. 14, No. 1, 2020, pp. 102–107, https://doi.org/10.14444/7014.[8] M. H. Daghighi, M. Pouriesa, M. Maleki et al., Migration Patterns of Herniated Disc Fragments: a Study on 1,020 Patients with Extruded Lumbar Disc Herniation, Spine Journal, Vol. 14, No. 9, 2014, pp. 1970-1977, https://doi.org/10.1016/j.spinee.2013.11.056.[9] M. Karademir, O. Eser, E. Karavelioglu, Adolescent Lumbar Disc Herniation: Impact, Diagnosis, and Treatment, J. Back Musculoskelet Rehabil, Vol 30, No. 2, 2017, pp. 347-352, https://doi.org/10.3233/bmr-160572.[10] R. G. Menon, M. V. W. Zibetti, M. Pendola et al., Measurement of Three-Dimensional Internal Dynamic Strains in the Intervertebral Disc of the Lumbar Spine with Mechanical Loading and Golden-Angle Radial Sparse Parallel-Magnetic Resonance Imaging, J Magn Reson Imaging, Vol. 54, No. 2, 2021, pp. 486–496, https://doi.org/10.1002/jmri.27591.
 
 

Far lateral lumbar disc herniation part 1: Imaging, neurophysiology and clinical features.

Far lateral lumbar disc herniations (FLLDH) represent a separate category of disc pathology which includes both intraforaminal and extraforaminal lumbar disc herniations, that are characterized by a peculiar clinical presentation, diagnostic and treatment modalities as compared to the more frequent median and paramedian disc hernias. Surgical treatment often represents the only effective weapon for the cure of this disease and over the years different approaches have been developed that can reach the region of the foramen or external to it, with different degrees of invasiveness. The diagnosis is more demanding and still underestimated as it requires a more detailed knowledge in the spine anatomy and dedicated radiological studies. Computerized tomography and in particular magnetic resonance imaging are the appropriate tools for the diagnosis of FLLDH. Despite the widespread use of these diagnostic tests, many cases of FLLDH are overlooked due to insufficiently detailed radiological examinations or due to the execution of exams not focused to the foraminal or the extraforaminal region. Neurophysiological studies represent a valid aid in the diagnostic classification of this pathology and in some cases they can facilitate the differential diagnosis with other types of radiculopathies. In the present study, a comprehensive review of the clinical presentation, epidemiology, radiological study and the neurophysiological aspects is presented.

Prognostic Value of Michigan State University (MSU) Classification for Lumbar Disc Herniation: Is It Suitable for Surgical Selection?

Lumbar disc herniation (LDH) is the most common cause of radiculopathy; patients with severe pain refractory to conservative management or neurological deficits are candidates to surgical procedures. Michigan State University (MSU) classification is a radiological codification considering both the size of the LDH and its medial to lateral location on the axial plane. The purpose of this retrospective study is to identify which kind of LDH, according to the MSU scheme, is more likely to cause a motor deficit. We performed a retrospective analysis on data obtained from 114 patients treated with 117 lumbar microdiscectomies after failure of non-operative care. All patients underwent neurological and functional evaluation before and after surgery according to the following: Oswestry Disability Index, visual analog scale, and Japanese Orthopaedic Association back pain evaluation questionnaire. Magnetic resonance imaging proved that disc herniation was classified according to the MSU scheme and was correlated with motor disturbances expressed according to Medical Research Council grade. Statistical analysis showed a significant correlation between the lateral location of disc herniation (preforaminal and extraforaminal LDH, respectively MSU B and MSU C) and the grade of muscle weakness, given that the LDH in these locations poorly responded to medical therapy and was at higher risk for motor deficit onset; no significant correlation with the size was observed. Beyond standardization of radiologic description, MSU classification proved to be useful in definition of prognosis and possibly in selection of surgical candidates. However, these data should be confirmed by prospective studies on a larger sample of patients, also including those under way for conservative treatment.

Surgery for extraforaminal lumbar disc herniation: a single center comparative observational study

BackgroundSurgery on extraforaminal lumbar disc herniation (ELDH) is a commonly performed procedure. Operating on this type of herniation is known to come with more difficulties than on the frequently seen paramedian lumbar disc herniation (PLDH). However, no comparative data are available on the effectiveness and safety of this operation. We sought out to compare clinical outcomes at 1 year following surgery for ELDH and PLDH.MethodsData were collected through the Norwegian Registry for Spine Surgery (NORspine). The primary outcome measure was change at 1 year in the Oswestry Disability Index (ODI). Secondary outcome measures were quality of life measured with EuroQol 5 dimensions (EQ-5D); and numeric rating scales (NRSs).ResultsData of a total of 1750 patients were evaluated in this study, including 72 ELDH patients (4.1%). One year after surgery, there were no differences in any of the patient reported outcome measurements (PROMs) between the two groups. PLDH and ELDH patients experienced similar changes in ODI (− 30.92 vs. − 34.00, P = 0.325); EQ-5D (0.50 vs. 0.51, P = 0.859); NRS back (− 3.69 vs. − 3.83, P = 0.745); and NRS leg (− 4.69 vs. − 4.46, P = 0.607) after 1 year. The proportion of patients achieving a clinical success (defined as an ODI score of less than 20 points) at 1 year was similar in both groups (61.5% vs. 52.7%, P = 0.204).ConclusionsPatients operated for ELDH reported similar improvement after 1 year compared with patients operated for PLDH.

Navigation-assisted extraforaminal lumbar disc microdiscectomy: Technical note.

Background:Extraforaminal lumbar disc herniation (ELDH) amounts of 7%–12% of all lumbar disc herniations. Although they have already been widely described, an optimal treatment is still under discussion in the literature.Objective:We describe a novel application of navigation using 2D/3D imaging system to plan an adequate surgical trajectory and performing a neuronavigated microdiscectomy in ELDH that has not been previously described.Methods:This is a retrospective study in a single institution. Between February 2017 and July 2020, a total of 12 patients (7 males and 5 females), with a mean age of 56 years (range 49–71 years), have been treated because of ELDH through a far lateral microdiscectomy using 2D/3D imaging system-assisted neuronavigation (O-arm).Results:No intraoperative and/or postoperative complications were recorded. Patients presented a mean preoperative Visual Analog Scale (VAS) score of 7.83 ± 0.83 (range 7–9). At the day of discharge, leg pain VAS score effectively improved, decreasing to a mean value of 1.83 ± 0.83 (range 1–3). Further, low back and radicular pain improvement was recorded at 1-, 6-, and 12-month follow-up, respectively.Conclusion:We described a novel use of 2D/3D imaging system navigation in the microsurgical treatment of ELDH that has not previously reported. This technique is safe and effective and provides more intraoperative details compared to fluoroscopy, which can be crucial for the success of the procedure and to reduce complications and particularly indicated in complex cases with altered anatomy.

Coronal magnetic resonance imaging of three-dimensional fast-field echo with water-selective excitation improves the sensitivity and reliability of identification of extraforaminal lumbar disc herniation

ObjectiveThe complete view of the nerve root, including the extraforaminal zone, can be displayed by coronal magnetic resonance imaging (MRI) of three-dimensional (3D) fast-field echo with water-selective excitation (CMRI). However, its sensitivity, specificity, and reliability for the diagnosis of extraforaminal lumbar disc herniation are unclear. We compared the sensitivity, specificity, and reliability of conventional MRI, CMRI, and 3D MRI for the identification of extraforaminal lumbar disc herniation.MethodsThis study involved 140 patients (68 with extraforaminal lumbar disc herniation and 72 with paramedian disc herniation). Their mean age was 44.57 ± 14.59 years. Conventional MRI, CMRI, and 3D MRI of all patients were evaluated by five experts. The reliability, sensitivity, and specificity of the three imaging techniques for identification of extraforaminal lumbar disc herniation were compared using kappa statistics and the chi-squared test.ResultsCMRI showed higher agreement (0.843) than conventional MRI (0.671) and 3D MRI (0.771) for the identification of extraforaminal lumbar disc herniation. CMRI demonstrated higher sensitivity (95.6% vs. 91.2%) than conventional MRI (85.3% vs. 70.6%) and 3D MRI (92.6% vs. 86.7%) regardless of whether performed by junior or senior surgeons.ConclusionsCMRI is helpful for identification of extraforaminal disc herniation by junior and senior orthopedic surgeons.

Endoscopic Transforaminal Discectomy Vs. Far Lateral Discectomy for Extraforaminal Disc Protrusions: Our Experience

Background: Extraforaminal disc herniations are challenging occurrences, requiring a more disruptive approach in terms of bony removal and muscles dissection. We compared outcomes and intraoperative findings between endoscopic transforaminal and far lateral discectomy in the treatment of extraforaminal disc protrusions Methods: We prospectively collected 38 patients who underwent surgery for lumbar extraforaminal disc prolapse, from January 2014 to December 2018. Twenty patients underwent far lateral microsurgical discectomy, whereas eighteen a percutaneous transforaminal endoscopic discectomy. Patients were randomly assigned to a treatment group and were followed-up at intervals of 3, 6, and 16 months. No patients were lost at follow-up. Data were collected on leg pain and disability degree, preoperatively and at follow-up visits, along with demographic data, operative time, amount of intraoperative blood loss, and any postoperative surgical adverse events. Eventually, data analyzed and compared between the two groups. Results: Mean operative time was significantly shorter for endoscopically treated patients compared to patients who underwent microdiscectomy (59.4 vs. 98 minutes, p-value < 0.001). Also, intraoperative blood loss was almost negligible (< 50 ml) for all endoscopically treated patients. There were no differences in terms of postoperative outcomes between patients treated with standard microsurgical techniques and patient who underwent endoscopic transforaminal discectomy at 3, 6, and 16 months of follow-up. Conclusions: transforaminal endoscopic discectomy is a feasible and safe procedure for the treatment of extraforaminal lumbar disc herniation. Our series highlighted the utility and feasibility of the technique, showing similar results to far lateral microsurgical technique.

Percutaneous Endoscopic Transforaminal Outside-In Outside Technique for Foraminal and Extraforaminal Lumbar Disc Herniations—Operative Technique

Different transforaminal endoscopic approaches have been developed for the surgical treatment of lumbar disc herniation: Kambin (intradiscal), Yeung (intraforaminal intradiscal), Ruetten (extreme lateral), transforaminal endoscopic surgical system (intraforaminal extradiscal) approach, and modifications. The operative technique for the treatment of foraminal and extraforaminal lumbar disc herniation through these surgical approaches has not been well described in reported studies. Moreover, each of these surgical approaches has limitations in the removal of migrated intra- or extraforaminal disc herniation. We have described, step by step, the operative technique of a modified percutaneous endoscopic transforaminal approach we have termed the "percutaneous endoscopic intra- and extraforaminal extradiscal approach or transforaminal outside-in outside [TOIO] approach" for the treatment of foraminal and extraforaminal lumbar disc herniation. From 2012 to 2018, 48 patients had undergone the percutaneous endoscopic TOIO approach for symptomatic foraminal and extraforaminal lumbar disc herniation. The inclusion criteria were the same as the microdiscectomy criteria. The exclusion criteria included patients with severe foraminal stenosis and disc degeneration, listhesis, and scoliosis. The pre- and postoperative clinical data, radiographic findings, and surgical technique were investigated. No intraoperative complications developed. All the patients showed progressive improvement of initial neurological deficits with complete recovery of motor weakness and L4, L5 hypoesthesia at 1 month postoperatively. One patient experienced persistent postoperative dysesthesia on the affected leg for ∼1 month. The percutaneous endoscopic TOIO approach is a minimally invasive, safe, and efficacious surgical procedure for the treatment of lumbar foraminal and extraforaminal disc herniation. Proper patient selection is mandatory to ensure a satisfactory outcome.

The modified transforaminal endoscopic technique in treating intracanalicular combining foraminal and/or extraforaminal lumbar disc herniations.

To develop a modified transforaminal endoscopic spine system (TESSYS®) technique for treating intracanalicular combining foraminal and/or extraforaminal lumbar disc herniation (ICFE-LDH), and evaluate the technical efficacy and safety. Twenty-three patients with ICFE-LDH underwent the modified TESSYS technique were enrolled. Magnetic resonance imaging (MRI) was used to verify the reduction of herniated disc. Pre- and post-operative neurological functions were compared by visual analogue scale (VAS) score, Oswestry disability index (ODI) and the modified MacNab criteria. The technical safety was evaluated by surgical complications. MRI demonstrated reductions of disc herniations in 22 patients (95.7%) after surgeries. The VAS scores were significantly improved at 1 year follow-up (low back: P=0.001, lower limbs: P<0.001), as well as ODI scores (P<0.001). 22 patients had achieved excellent and good recovery postoperatively according to the modified MacNab criteria. One patient (4.3%) underwent a reoperation due to postoperative recurrence of disc herniation. Another patient complained postoperative causalgia in 8 weeks, the symptom alleviated after conservative treatment at 1 year follow-up (VAS: back, 3, lower limbs, 0; ODI: 20%). The incidence rate of surgical complication was 8.7%. The modified TESSYS technique is a minimally-invasive, effective and safe surgery for treating ICFE-LDHs in selected patients.

Recurrent upper lumbar disc herniation treated via the transforaminal approach using microendoscopy-assisted lumbar discectomy: a case report

BackgroundAlthough microendoscopy-assisted lumbar discectomy for lateral or extraforaminal lumbar disc herniations via the lateral approach has previously been reported, microendoscopy-assisted lumbar discectomy for central or paramedian disc herniations via the lateral approach has not been reported.We report the first case of recurrent upper lumbar disc herniation (L2–L3) treated with microendoscopy-assisted lumbar discectomy via the transforaminal approach. No microendoscopy-assisted lumbar discectomy for recurrent upper lumbar disc herniation via the transforaminal approach has previously been reported. Percutaneous endoscopic lumbar discectomy via the transforaminal approach is very useful as a minimally invasive surgery for disc herniations. We applied percutaneous endoscopic lumbar discectomy via the transforaminal approach, and invented a new microendoscopy-assisted lumbar discectomy via the transforaminal approach.Case presentationA 79-year-old Japanese man was operatively managed for recurrent L2–L3 herniation. An 18 mm skin incision was made approximately 70 mm from the midline to the lateral side to allow a sufficiently angled trajectory to the extraforaminal space. The transforaminal approach was used. The exiting nerve root was identified along its course inferior to the pedicle. The lateral portion of the pars interarticularis and the facet joint was removed using a high-speed drill under the guidance of an endoscope. The tip of the endoscope was set at the lateral side of the dura mater. The dura mater was retracted medially and gently, and the herniated disc fragments were removed safely. All symptoms were relieved postoperatively. Postoperative magnetic resonance imaging demonstrated disappearance of all herniated disc fragments. A postoperative three-dimensional computed tomographic scan demonstrated the complete preservation of the facet joint.ConclusionsThis is the first report of a case of recurrent upper lumbar disc herniation treated with microendoscopy-assisted lumbar discectomy via the transforaminal approach. This procedure allows for the use of a nerve retractor and other instruments to detach adhesions from the dura mater. This procedure has the advantages of clear visualization of the dura mater, exiting nerve root, and traversing nerve root, and diminished risk of nerve injury, and complete preservation of the articular surface of the facet joint.

Extraforaminal microscopic assisted percutaneous nucleotomy for foraminal and extraforaminal lumbar disc herniations

BackgroundForaminal and extraforaminal lumbar disc herniations are uncommon. The main presentation is radicular pain related to the exiting nerve root at the affected level. Different approaches for surgical intervention have been described. PurposeThis study aimed to evaluate the clinical outcome, complications recurrence, and reoperation rate of extraforaminal microscopic-assisted percutaneous nucleotomy, with literature review focusing on complications and recurrence rate. Study DesignThis is a prospective cohort study done in a high-flow spine center in Germany. Patient SampleBetween October 2012 and October 2015, 76 patients (35 women and 41 men) with foraminal or extraforaminal lumbar disc prolapse were operated on. Outcome MeasuresThe following were the outcome measures: (1) self-report measures: Visual Analogue Scale (VAS) for leg pain and back pain; (2) physiological measures: standing plain X-rays (anterioposterior, lateral, and dynamic views); and (3) functional measures: Oswestry Disability Index (ODI) (validated German version) and Odom's criteria. MethodsAll patients were operated upon with trans-tubular extraforaminal microscopic-assisted percutaneous nucleotomy (EF-MAPN) technique. Preoperative clinical and neurologic evaluations were done. The mean follow-up period was 38 months (range 12–54). The study has not received funding for research from any organization. All authors do not have any conflict of interest. ResultsThe mean age was 54 years. The most commonly affected level was L4/L5 (34 patients). The mean preoperative VAS for leg pain was 7.6 (3–10), which improved to 1.4 (0–4) postoperatively. The average operative time was 57.5 minutes. There were no intraoperative complications. One patient had temporary postoperative quadriceps weakness (L4 radiculopathy) that was completely improved at 3 months' follow-up. Another patient had deep venous thrombosis after discharge. Two patients had recurrences that necessitated another operation within the first 6 months postoperatively. Both were followed up for 1 year without a second recurrence. ConclusionTrans-tubular percutaneous extraforaminal microscopic-assisted nucleotomy is effective for foraminal and extraforaminal disc herniations. It is a muscle-splitting minimally invasive approach with minimal morbidity. Complications, recurrence, and reoperation rate are not different compared with microsurgical open or endoscopic techniques.

Advantages and disadvantages of posterolateral approach for percutaneous endoscopic lumbar discectomy.

Percutaneous endoscopic lumbar discectomy (PELD) is one of the less invasive treatments for lumbar disc herniation (LDH), and has 3 different operative approaches. This study focused on the posterolateral approach (PLA) and investigated the appropriate operative indication. PLA was performed in 29 patients with foraminal and extraforaminal LDH. The height and width of the foramen, LDH type, and positional relationship between LDH and the foramen were radiologically evaluated. Foraminoplasty was also performed in 12 cases including those combined with intra-canal LDH or osseous foraminal stenosis. Pre- and postoperative status was evaluated using Numerical Rating Scale (NRS) scores. Patient mean age was 56.8 years; there was single-level involvement at L3/4 (13 cases) and at L4/5 (13 cases). The mean pre- and postoperative NRS scores were 6.1 and 1.8, respectively. Early recurrence developed in a patient who was found to have local scoliosis at the corresponding vertebral level. PLA can be safely used to treat foraminal and extraforaminal LDH with foraminal height ≥13 mm and foraminal width ≥7 mm. The procedure is effective for preserving the facet joint; however, we should carefully consider the indications when local scoliosis and/or instability are present.

Advantages and disadvantages of posterolateral approach for percutaneous endoscopic lumbar discectomy

Background: Percutaneous endoscopic lumbar discectomy (PELD) is one of the less invasive treatments for lumbar disc herniation (LDH), and has 3 different operative approaches. This study focused on the posterolateral approach (PLA) and investigated the appropriate operative indication. Methods: PLA was performed in 29 patients with foraminal and extraforaminal LDH. The height and width of the foramen, LDH type, and positional relationship between LDH and the foramen were radiologically evaluated. Foraminoplasty was also performed in 12 cases including those combined with intra-canal LDH or osseous foraminal stenosis. Pre- and postoperative status was evaluated using Numerical Rating Scale (NRS) scores. Results: Patient mean age was 56.8 years; there was single-level involvement at L3/4 (13 cases) and at L4/5 (13 cases). The mean pre- and postoperative NRS scores were 6.1 and 1.8, respectively. Early recurrence developed in a patient who was found to have local scoliosis at the corresponding vertebral level. Conclusions: PLA can be safely used to treat foraminal and extraforaminal LDH with foraminal height ≥13 mm and foraminal width ≥7 mm. The procedure is effective for preserving the facet joint; however, we should carefully consider the indications when local scoliosis and/or instability are present.

Complications and Re-operation Rate after Extra-foraminal Microscopic-Assisted Percutaneous Nucleotomy

IntroductionForaminal and extra-foraminal lumbar disc herniations are uncommon. Main presentation is radicular pain related to the exiting nerve root in the affected level. Different approaches for surgical intervention include median or para-median open microscopic-assisted techniques, endoscopic approach or trans-tubular microscopic-assisted percutaneous technique. Patients and MethodsBetween October 2012 and March 2014, 40 patients (18 females and 22 males) with foraminal or extra-foraminal lumbar disc prolapse were operated on in our center. Extra-foraminal percutaneous trans-tubular microscopic-assisted approach was used. Preoperative investigations included plain radiographs and MRI. Preoperative clinical evaluation included Visual Analogue Scale (VAS) for radicular pain and neurological state. The mean follow up period was 18 months (range 12 - 30). ResultsThe mean age was 56 years. The most commonly affected level was L4/5 (22 patients = 55%). The mean preoperative VAS for leg pain was 82 mm, improved to 15 postoperatively. The average operative time was 69 minutes. There were no intraoperative complications. One patient had temporary postoperative quadriceps weakness (L4 radiculopathy) that was completely improved at 3 months follow up. Another patient had deep venous thrombosis after discharge and he was readmitted. Two patients had recurrence within the first 6 months postoperatively. They were re-operated using the same technique without complications. Both were followed up for one year without a second recurrence. Two patients with primarily severe degenerative changes and neuroforaminal stenosis had recurrence of symptoms with back pain and leg pain, re-operation as Transforaminal Lumbar Interbody Fusion (TLIF) was done ConclusionTrans-tubular percutaneous extra-foraminal microscopic-assisted nucleotomy is advantageous for foraminal and extra-foraminal disc herniations. It is a muscle splitting minimal-invasive approach with minimal morbidity. Re-operation rate is not different compared with microsurgical open or endoscopic techniques. Results seems to be better in cases with sequestrated disc lesion rather than degenerative neuroforaminal stenosis.

Spontaneous Resolution of an Extraforaminal Lumbar Disc Herniation; Report of a Case and Review of the Literature

Extraforaminal lumbar disc herniations (ELDHs) are a relatively uncommon cause of lumbar radiculopathy. In the patients suffering this kind of disc herniation, severe intractable radiculopathy due to dorsal root ganglion compression usually leads to surgery. However, although the value of conservative strategy for spontaneous resolution of intracanal lumbar sequestrated disc herniation is a well-known scenario, but it is not verified in extraforaminal disc herniation. Herein, a 53-year-old man with severe left -sided femoral radiculopathy at the vicinity of L3 which was associated with decreased knee jerk is presented. MRI revealed a huge extraforaminal disc herniation at L3-L4 level on the right side. Surgery was recommended, but since the patient was reluctant to undergo surgery, a period of conservative treatment, with transforaminal block, combined with NSAID’s prescription result in dramatic pain amelioration. Control MRI after 3 months showed relative hyperintensity of the corresponding disc. However, MRI at 9- months follow -up where the patient was completely pain free, revealed disappearance of the offending disc. To our knowledge, the scenario of spontaneous resolution of extraforaminal disc herniation has not been reported previously in the literature.

Postoperative Clinical Outcome and Risk Factors for Poor Outcome of Foraminal and Extraforaminal Lumbar Disc Herniation.

ObjectiveWe evaluated postoperative outcomes in patients who have lumbar foraminal or extraforaminal disc herniation (FELDH) and suggested the risk factors for poor outcomes.MethodsA total of 234 patients were selected for this study. Pre- and post-operative Visual Analogue Scale (VAS) and Korean version Oswestry Disability Index (KODI) were evaluated and the changes of both score were calculated. Outcome was defined as excellent, good, fair, and poor based on Mcnab classification. The percentage of superior facetectomy was calculated by using the Maro-view 5.4 Picture Archiving Communication System (PACS).ResultsParamedian lumbar discectomy was performed in 180 patients and combined lumbar discectomy was performed in 54 patients. Paramedian lumbar discectomy group showed better outcome compared with combined discectomy group. p value of VAS change was 0.009 and KODI was 0.013. The average percentage of superior facetectomy was 33% (range, 0–79%) and it showed negative correlation with VAS and KODI changes (Pearson coefficient : -0.446 and -0.498, respectively). Excellent or good outcome cases (Group I) were 136 (58.1%) and fair or poor outcome cases (Group II) were 98 (41.9%). The percentage of superior facetectomy was 26.5% at Group I and 42.5% at Group II. There was significant difference in superior facetectomy percentage between Group I and II (p=0.000).ConclusionThis study demonstrated that paramedian lumbar discectomy with preservation of facet joints is an effective and good procedure for FELDH. At least 60% of facet should be preserved for excellent or good outcomes.

Disc Fragment Herniectomy Through a Facet Joint Quadrantectomy for Extraforaminal Lumbar Herniation: Technique and Results

Extraforaminal lumbar disc herniation (EFLDH) accounts for 7%-12% of all lumbar disc herniations. We report on a surgical technique for EFLDH, which requires only minimal resection of the facet joint and also allows access to the preforaminal space, if necessary. The medical records of 61 consecutive patients treated with disc fragment herniectomy through a facet joint quadrantectomy for EFLDH at the Universitair Ziekenhuis Brussel were critically evaluated with respect to preoperative clinical signs and symptoms, surgery-related complications and outcome at 6 weeks after intervention. Patient satisfaction after the surgery was evaluated using the MacNab classification. The prevalence of leg pain decreased from 100% before the intervention to 19.7% at follow-up. Only 9 patients (14.8%) suffered from residual motor deficit at follow-up, compared with 37 patients (60.7%) in the preoperative situation. The postoperative improvement was highly significant for all parameters (P < 0.0001) and this evolution is also reflected in the MacNab classification showing 62.3% excellent, 23.0% good, 13.1% fair, and only 1.6% poor satisfaction. Using logistic regression analysis, only the presence of a preoperative sensory deficit was found to be an independent predictor for excellent patient satisfaction on the MacNab classification. Disc fragment herniectomy through a facet joint quadrantectomy for EFLDH is a safe and minimal invasive technique resulting in very satisfactory results. Preservation of facet joint stability and the possibility to convert to a classic approach to reach for preforaminal components, if necessary, are major advantages of this technique.

Percutaneous endoscopic lumbar discectomy in the treatment of severe extraforaminal lumbar disc herniation

Objective To evaluate the feasibility and effectiveness of percutaneous endoscopic lumbar discectomy in the treatment of severe extraforaminal lumbar disc herniation. Methods From February 2012 to February 2015,72 cases of severe extraforaminal lumbar disc herniation were treated by percutaneous endoscopic lumbar discectomy and nerve decompression in our department.The clinical data(44 males and 28 females) were collected for analysis. The age ranged from 20 to 79 years, with an average age of(45. 4±3. 6) years.Before and 3 months, 6 months and last followup after operation, visual analog pain score(VAS) and functional disturbance index(ODI) score, and the modified Macnab criteria were performed to evaluate the clinical curative effect. Results Operation time ranged from 65 to 150 min, with an average of 65 min.Average intraoperative blood loss was from 25 to 150 ml, with an average of 65 ml.The average postoperative hospital stay was 5. 6 days.Before and 3 months, 6 months and last follow-up after operation, the VAS lumbago scores were 7. 92±2. 35,2. 75±1. 80,2. 32±1. 27 and 1. 88±1. 15 separately(P< 0. 01),and ODI scores were 68. 25±18. 50, 23. 54±17. 45, 20. 23±14. 10 and 15. 52±5. 80 respectively(P< 0. 01). According to the modified Macnab criteria, the excellent and good rate was 91. 7%. Conclusion Satisfacdtory short-term effectiveness can be obtained by percutaneous endoscopic lumbar discectomy for the treatment of severe extraforaminal lumbar disc herniation and it turned out to be safe and minimally invasive. Key words: Percutaneous endoscopic lumbar discectomy; Lumbar disc herniation; Curative effect analysis

Introduction: Minimally invasive spine surgery: the greatest advance in medicine?

In the past century, significant advances have been made in spine surgery, and in this issue of Neurosurgical Focus, we will review the myriad of treatment options currently available to treat spinal disorders. These minimally disruptive techniques and approaches to the spine have dramatically altered the natural history of previously difficult lesions and spinal conditions. Harvey Cushing would be proud of the work done in the fields of neurosurgery, radiology, engineering, physics, and orthopedics for the advancement of spine surgery. In modern medicine, there are few advances that have had a more meaningful impact on patient outcomes than minimally invasive spine procedures. Patients presenting with painful radiculopathies and neural compression can be treated successfully with minimal access procedures and sent home the same day. Sven Eicker and colleagues discuss their experience with extraforaminal lumbar disc herniations. Their minimal access microsurgical approach with the endoscopic technique seemed to produce less tissue trauma and instability, while providing significant improvement of functional outcomes. Surgical management of tumors, fractures, and spinal deformities has significantly improved with these emerging technologies and techniques. Percutaneous ped icle screw fixation for spine fractures can be done with minimal blood loss, and patients can be mobilized immediately, resulting in a decrease in postsurgical complications. Flexion-distraction spine injuries, which are extremely unstable, classically consisting of a fracture line through all 3 columns, require surgical fixation to avoid neurological deterioration, help stabilize the spine, and restore spinal balance. Historically, these injuries were all treated by means of the standard posterior open approach with instrumented fusion. Percutaneous pedicle screw fixation for these unstable spine injuries has been recently reported in the literature. Andrew Grossbach and colleagues report on their institutional experience of treating these fractures with both surgical techniques and review the current literature. Although it was a small prospective study, there was improvement in kyphotic angulation, and the authors found no significant difference in ASIA scores or the degree of kyphotic angulation between the percutaneous and open surgical groups. Percutaneous pedicle screw fixation appeared to have similar efficacy in the treatment of flexion-distraction injuries, and it allowed for reduced blood loss and tissue damage compared to open surgical techniques. Instrumentation systems have improved significantly in the past 10 years, and today’s hardware allows surgeons to realign the spine and contour the rod to the spine. How about treating spinal stenosis and spondylolisthesis with a minimally invasive interspinous fixation device? Nai-Feng Tian and colleagues found that there was a high incidence of heterotopic ossification after interspinous fixation. Lateral approaches have been applied to treat spinal conditions, such as scoliosis, in recent years. The prior treatment deformity paradigms of shortening the spine by performing osteotomies posteriorly are utilized less. Scoliosis procedures can now be staged with multilevel lateral cages that lengthen the spine, correct the deformity, increase spinal balance, provide a more natural curve, and indirectly decompress neural elements. Armen Deukmedjian and coauthors reviewed their lateral approach for adult degenerative scoliosis. They provided useful data about patient selection for the application of lateral approaches for adult scoliosis surgery. Isolated lateral interbody fusions were deemed suitable for patients with preserved spinal pelvic harmony. Sagittal imbalance may be addressed with advanced lateral approaches, such as releasing the anterior longitudinal ligament. Is there a role for minimally disruptive procedures in the treatment of intradural pathology? The article by Gandhi et al. eloquently describes utilizing a paramedian minimally invasive tubular retractor to access the spine and microscopic instruments to remove intradural pathology. Historically, intradural spinal lesions have been treated from a midline posterior approach using standard microsurgical techniques. The authors retrospectively reviewed their operative blood loss, length of stay, imaging characteristics, and outcomes. Introduction

Transtubular microsurgical approach to treating extraforaminal lumbar disc herniations

Approaches to treating extraforaminal lumbar disc herniations can be challenging due to the unique anatomy and the need to prevent spinal instability. Numerous approaches, including conventional midline, paramedian, minimally invasive, and full endoscopic approaches, have been described. The purposes of this study were to point out the outcome and clinical advantages of a transtubular microsurgical approach and to describe and illustrate this technique. Between 2009 and 2012, a series of 51 patients underwent a minimally invasive dilative transtubular microsurgical approach for the treatment of extraforaminal lumbar disc herniations. All patients were clinically evaluated using the visual analog scale (VAS) and Oswestry Disability Index preoperatively and 6 months postoperatively. Both pain scores and functional status showed significant improvement after surgery (p < 0.001): radicular pain decreased from VAS score of 7.9 to one of 1.3, lower back pain from VAS score of 2.4 to 1.4, and the Oswestry Disability Index from 42.0 to 12.3. Subgroup analyses revealed no differences in outcome regarding obesity or timing of surgery (early vs late intervention). Highly significant was the correlation between preoperative radicular pain activity and timing of surgical intervention (p < 0.001). The dilative transtubular microsurgical approach combines the advantages of the conventional open muscle-splitting approach and the endoscopic approach. The technique is easy to use with a steep learning curve. Less muscle trauma and the absence of bony resection prevent facet pain and instability, thereby contributing to a rapid recovery. Patients in this series improved excellently in the short-term follow-up.