Comparison of the clinical efficacy of percutaneous transforaminal endoscopic discectomy and traditional laminectomy in the treatment of recurrent lumbar disc herniation.

ABSTRACT: A few years ago, percutaneous transforaminal endoscopic discectomy (PTED) began to prevail in clinical treatment of recurrent lumbar disc herniation (RLDH), whereas traditional laminectomy (TL) was treated earlier in RLDH than PTED. This study aimed to compare the clinical efficacy of PTED and TL in the treatment of RLDH.Between November 2012 and October 2017, retrospective analysis of 48 patients with RLDH who were treated at the Cancer Hospital, Chinese Academy of Sciences, Hefei and Department of Orthopaedics, Second Affiliated Hospital of Anhui Medical University. Perioperative evaluation indicators included operation time, the intraoperative blood loss, length of incision and hospitalization time. Clinical outcomes were measured preoperatively, and at 1 days, 3 months, and 12 months postoperatively. The patients' lower limb pain was evaluated using Oswestry disability index (ODI) and visual analog scale (VAS) scores. The ODI is the most widely-used assessment method internationally for lumbar or leg pain at present. Every category comprises 6 options, with the highest score for each question being 5 points. higher scores represent more serious dysfunction. The VAS is the most commonly-used quantitative method for assessing the degree of pain in clinical practice. The measurement method is to draw a 10 cm horizontal line on a piece of paper, 1 end of which is 0, indicating no pain, which the other end is 10, which means severe pain, and the middle part indicates different degree of pain.Compared with the TL group, the operation time, postoperative bed-rest time, and hospitalization time of the PTED group were significantly shorter, and the intraoperative blood loss was also reduced. These differences were statistically significant (P < .01). There were no significant differences in VAS or ODI scores between the two groups before or after surgery (P > .05).PTED and TL have similar clinical efficacy in the treatment of RLDH, but PTED can shorten the operation time, postoperative bed-rest time and hospitalization time, and reduce intraoperative blood loss, so the PTED is a safe and effective surgical method for the treatment of RLDH than TL, but more randomized controlled trials are still required to further verify these conclusions.

Percutaneous Transforaminal Endoscopic Discectomy Versus Open Microdiscectomy for Lumbar Disc Herniation: A Systematic Review and Meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To give a systematic overview of effectiveness of percutaneous transforaminal endoscopic discectomy (PTED) compared with open microdiscectomy (OM) in the treatment of lumbar disk herniation (LDH). SUMMARY OF BACKGROUND DATA: The current standard procedure for the treatment of sciatica caused by LDH, is OM. PTED is an alternative surgical technique which is thought to be less invasive. It is unclear if PTED has comparable outcomes compared with OM. METHODS: Multiple online databases were systematically searched up to April 2020 for randomized controlled trials and prospective studies comparing PTED with OM for LDH. Primary outcomes were leg pain and functional status. Pooled effect estimates were calculated for the primary outcomes only and presented as standard mean differences (SMD) with their 95% confidence intervals (CI) at short (1-day postoperative), intermediate (3-6 months), and long-term (12 months). RESULTS: We identified 2276 citations, of which eventually 14 studies were included. There was substantial heterogeneity in effects on leg pain at short term. There is moderate quality evidence suggesting no difference in leg pain at intermediate (SMD 0.05, 95% CI -0.10-0.21) and long-term follow-up (SMD 0.11, 95% CI -0.30-0.53). Only one study measured functional status at short-term and reported no differences. There is moderate quality evidence suggesting no difference in functional status at intermediate (SMD -0.09, 95% CI -0.24-0.07) and long-term (SMD -0.11, 95% CI -0.45-0.24). CONCLUSION: There is moderate quality evidence suggesting no difference in leg pain or functional status at intermediate and long-term follow-up between PTED and OM in the treatment of LDH. High quality, robust studies reporting on clinical outcomes and cost-effectiveness on the long term are lacking.Level of Evidence: 2.

Treatment of cervical spondylotic radiculopathy with posterior percutaneous endoscopic cervical discectomy: Short-term outcomes of 24 cases.

To determine the short-term clinical outcomes of single-segment cervical spondylotic radiculopathy treated with posterior percutaneous endoscopic cervical discectomy (PPECD).Data of a total of 24 patients who underwent PPECD and local anesthesia for single-level segmental cervical spondylotic radiculopathy between March 2016 and December 2017 were reviewed. The Japanese Orthopaedic Association, visual analog scale (VAS), and neck disability index scores at preoperative 1 day, postoperative 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year were recorded. The modified MacNab criteria at the last follow-up were re-recorded for the evaluation of clinical effectiveness.All operations were successfully completed under endoscopic guidance. No patient showed spinal cord, nerve root, vascular injuries, dural tears or other complications. The postoperative VAS scores of the arm and neck were significantly reduced compared with the preoperative VAS scores (P < .05), while postoperative the Japanese Orthopaedic Association scores were significantly increased (P < .05). The postoperative neck disability index scores were significantly reduced compared with preoperative scores (P < .05). The modified MacNab criteria at the last follow-up showed 16 excellent cases, 8 good cases, 0 fine cases, and 0 poor cases. Postoperative magnetic resonance imaging and cervical 3-dimensional computed tomography reconstruction showed that the intervertebral disc was adequately resected and the nerve root was not under compression.PPECD is safe and effective for the treatment of single-segment cervical spondylotic radiculopathy.

Efficacy and safety of percutaneous transforaminal endoscopic discectomy in the treatment of lumbar spinal stenosis combined with osteoporosis.

OBJECTIVE: To investigate the efficacy and safety of percutaneous transforaminal endoscopic discectomy (PTED) in the treatment of lumbar spinal stenosis (LSS) combined with osteoporosis. METHODS: Eighty patients with LSS combined with osteoporosis were divided into a control and PTED group, which received conventional transforaminal lumbar interbody fusion and PTED, respectively. The surgical indications, incision visual analogue scale (VAS), lumbar and leg pain VAS, lumbar Japanese Orthopaedic Association (JOA) and Oswestry disability index (ODI) scores, bone mineral density (BMD), and adverse reactions were observed. RESULTS: Compared with the control group, in the PTED group, the operation time, bleeding loss and hospitalization duration, incision VAS scores at postoperative 12, 24 and 48 h and lumbar and leg pain VAS and lumbar ODI scores on postoperative 6 months were significantly decreased (P < 0.01), and the lumbar JOA score on postoperative 6 months was significantly increased (P < 0.05). There was no significant difference in BMD between two groups (P > 0.05). Compared with the control group, in the PTED group, the total effective rate was significantly higher (P < 0.05), and the incidence of adverse reactions was significantly lower (P < 0.05). CONCLUSIONS: PTED is safe and effective in the treatment of LSS combined with osteoporosis.

Efficacy and safety of percutaneous transforaminal endoscopic discectomy in the treatment of lumbar spinal stenosis combined with osteoporosis

SUMMARY OBJECTIVE: To investigate the efficacy and safety of percutaneous transforaminal endoscopic discectomy (PTED) in the treatment of lumbar spinal stenosis (LSS) combined with osteoporosis. METHODS: Eighty patients with LSS combined with osteoporosis were divided into a control and PTED group, which received conventional transforaminal lumbar interbody fusion and PTED, respectively. The surgical indications, incision visual analogue scale (VAS), lumbar and leg pain VAS, lumbar Japanese Orthopaedic Association (JOA) and Oswestry disability index (ODI) scores, bone mineral density (BMD), and adverse reactions were observed. RESULTS: Compared with the control group, in the PTED group, the operation time, bleeding loss and hospitalization duration, incision VAS scores at postoperative 12, 24 and 48 h and lumbar and leg pain VAS and lumbar ODI scores on postoperative 6 months were significantly decreased (P < 0.01), and the lumbar JOA score on postoperative 6 months was significantly increased (P < 0.05). There was no significant difference in BMD between two groups (P > 0.05). Compared with the control group, in the PTED group, the total effective rate was significantly higher (P < 0.05), and the incidence of adverse reactions was significantly lower (P < 0.05). CONCLUSIONS: PTED is safe and effective in the treatment of LSS combined with osteoporosis.

RESUMO: OBJETIVO: Investigar a eficácia e segurança da discectomia endoscópica percutânea transforaminal (DEPT) no tratamento da estenose lombar (EL) combinada à osteoporose. MÉTODOS: Oitenta pacientes com EL combinada à osteoporose foram divididos entre um grupo de controle e um grupo de DEPT, que receberam tratamento convencional com fusão intersomática lombar transforaminal e DEPT, respectivamente. As indicações cirúrgicas, a escala analógica visual (VAS) da incisão e de dor lombar e nas pernas, os escores lombares de acordo com a Associação Ortopédica Japonesa (JOA) e o Oswestry Disability Index (ODI), a densidade mineral óssea (DMO) e possíveis reações adversas foram observados. RESULTADOS: Em comparação com o grupo de controle, no grupo de DEPT o tempo de operação, a perda de sangue e duração de internação, os escores VAS da incisão no pós-operatório após 12, 24 e 48 h, o VAS para dor lombar e nas pernas e os escores ODI lombares após 6 meses de pós-operatório foram significativamente menores (P < 0,01); já o escore JOA lombar após 6 meses de pós-operatório foi significativamente maior (P < 0,05). Não houve diferença significativa na densidade mineral óssea entre os dois grupos (P > 0,05). Em comparação com o grupo de controle, o grupo de DEPT teve uma taxa efetiva total significativamente maior (P < 0,05), e a incidência de reações adversas foi significativamente menor (P < 0,05). CONCLUSÕES: A discectomia endoscópica percutânea transforaminal é segura e eficaz no tratamento de EL combinada à osteoporose.

Effectiveness of Percutaneous Intradiscal Decompression Therapy in Thoracic Disc Herniation

Aims: Although there have been many studies about lumbar and cervical ablation procedures, few studies have been performed in the thoracic region. To evaluate the clinical results of a percutaneous disc decompression device in patients with radicular symptoms and/or dorsal pain due to thoracic disc herniation. Methods: Eleven patients with thoracic disc herniation and/or degenerative discs (all in T10-T11, or T11-T12 levels) who did not respond to conservative treatments were undergoing ablation and compression procedures. Pain and radicular symptoms consistent with the thoracolumbar region were confirmed via abnormal magnetic resonance imaging findings after detailed anamnesis and physical examination. All patients were evaluated before and 1, 3, 6, and 12 months after treatment using the visual analog scale score. The patient satisfaction scale was used to evaluate the level of patient satisfaction at the end of the treatment at 12 months. Results: The median visual analog scale score was 7.00±0.45 points before treatment and 2.73±0.65 points at 12 months post-procedure and were statistically significant (p<0.001). The results of pairwise comparisons using the Bonferroni Corrected Wilcoxon Signed-Rank test showed that there were statistically significant differences. The mean visual analog scale score at the beginning (7.00±0.45) was significantly higher than the mean score of other months. Postoperative improvement was significant with a 99% confidence interval. No complications that may cause permanent damage occurred. Conclusion: Percutaneous disc decompression is an effective and safe procedure to treat pain caused by lower thoracic intervertebral disc disease, which did not respond to conservative treatments.

Lumbar herniated disc - endoscopic discectomy treatment.

The Guidelines Project, an initiative of the Brazilian Medical Association, aims to combine information from the medical field in order to standardize producers to assist the reasoning and decision-making of doctors. The information provided through this project must be assessed and criticized by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical status of each patient.

A Novel Targeted Foraminoplasty Device Improves the Efficacy and Safety of Foraminoplasty in Percutaneous Endoscopic Lumbar Discectomy: Preliminary Clinical Application of 70 Cases.

OBJECTIVE: Percutaneous endoscopic lumbar discectomy (PELD) has become a mature and mainstream surgical technique for treating lumbar disc herniation (LDH); however, there is a steep learning curve with PELD, especially for puncture and foraminoplasty. In this study, we assessed the outcome and safety of a novel quantificational and targeted foraminoplasty device named ZESSYS for LDH. METHODS: From September to December of 2016, 70 patients with symptomatic LDH were enrolled in the study. The patients were assigned randomly to either the ZESSYS group or the conventional TESSYS group. We recorded the cannula introduction time, decompression time, radiation exposure time, intraoperative pain feeling score, visual analog scale, Oswestry Disability Index, and Macnab criteria score of the 2 groups. The mean follow-up period was 14 months. RESULTS: The average cannula introduction time (16.50 ± 3.29 minutes) and the radiation exposure time (40.71 ± 6.23 seconds) in the ZESSYS group were significantly reduced compared with the TESSYS group (cannula introduction time, 20.06 ± 3.37 minutes, P = 0.000; radiation exposure time, 49.20 ± 7.84 seconds, P = 0.000). Intraoperative pain feeling score in the ZESSYS group was significantly improved compared with the TESSYS group (P = 0.021). There were no significant differences between the 2 groups for decompression time (P = 0.617), Macnab criteria (P = 0.769), or visual analog scale and Oswestry Disability Index scores at the same time point (P > 0.05). No serious complication was observed in any patients in either group. CONCLUSIONS: The novel targeted foraminoplasty technique with the specially designed double-cannulas is an effective and safe treatment for lumbar intervertebral disc herniation. It reduces the difficulty of PELD learning, minimizes radiation exposure, and decreases intraoperative pain associated with foraminoplasty.

Comparison of 7 Surgical Interventions for Lumbar Disc Herniation: A Network Meta-analysis.

BACKGROUND: The number of interventions on intervertebral discs rapidly increased and the treatment options for lumbar disc surgery quickly evolved. It is important that the safety and efficacy of all new innovative procedures be compared with currently accepted forms of treatment; however, the previous pairwise meta-analyses could not develop the hierarchy of these treatments. OBJECTIVES: The purpose of the study is to perform a network meta-analysis to evaluate the clinical results of 7 surgical interventions for the treatment of lumbar disc herniation. STUDY DESIGN: Network meta-analysis of randomized controlled trials (RCTs) for multiple treatment comparisons of lumbar disc herniation. METHODS: We performed a Bayesian-framework network meta-analysis of RCTs to compare 7 surgical interventions for people with lumbar disc herniation. The eligible RCTs were identified by searching Embase, Pubmed, the Cochrane Central Register of Controlled Trials (CENTRAL), and Google scholar. Data from 3 outcomes (success, complications, and reoperation rate) were independently extracted by 2 authors. RESULTS: A total of 29 RCTs including 3,146 participants were finally included into this article. Our meta-analysis provides hierarchies of these 7 interventions. For the success rate the rank probability (from best to worst): percutaneous endoscopic lumber discectomy (PELD) > standard open discectomy (SOD) > standard open microsurgical discectomy (SOMD) > chemonucleolysis (CN) > microendoscopic discectomy (MED) > percutaneous laser disc decompression (PLDD) > automated percutaneous lumber discectomy (APLD). For the complication rate the rank probability (from best to worst): PELD > SOMD > SOD > MED > PLDD > CN > APLD. For the reoperation rate the rank probability (from best to worst): SOMD > SOD > MED > PLDD > PELD > CN > APLD. LIMITATIONS: The limitations of this network meta-analysis include the range of study populations and inconformity of the follow-up times and outcome measurements. CONCLUSIONS: This meta-analysis provides evidence that PELD might be the best choice to increase the success rate and decrease the complication rate, moreover SOMD might be the best option to drop the reoperation rate. APLD might lead to the lowest success rate and the highest complication and reoperation rate. Higher quality RCTs and direct head to head trials are needed to confirm these results.Key words: Lumbar disc herniation, discectomy, minimally invasive surgery, network meta-analysis.

Relationship Between Percutaneous Procedures and Lumbar Infections Based on Data From The National Health Insurance Review & Assessment Service of Korea.

STUDY DESIGN: A study from the National health insurance database. OBJECTIVE: To investigate the relationship between percutaneous procedures or open surgeries and spinal infections using the 5-year large unit national dataset. SUMMARY OF BACKGROUND DATA: There is no nation-based research data on the relationship between percutaneous procedures and spinal infections in Korea. MATERIALS AND METHODS: This study used disease codes (ICD-10: International Classification of Disease) and operation fee codes (national medical insurance) registered in the National Health Insurance Review & Assessment Service for the 5 years from 2007 to 2011. Using the above disease codes, the number of each percutaneous procedure, open surgery, and the number of lumbar infections were investigated by the regional and national units, and the relationship between procedures or open surgeries and lumbar infection was compared statistically. RESULTS: Lumbar infection showed a gradual growing annual trend, with a 3-fold increase in 2011 compared with 2007. Percutaneous procedures (nerve blocks) increased by approximately 2.6 times over 4 years. Kyphoplasty tended to decrease each year. Open surgeries (posterior fusion, discectomy, and laminectomy) were at a similar level each year. Lumbar infection and percutaneous procedures were positively correlated, and a negative correlation was observed between kyphoplasty and open surgeries. The incidence of lumbar infection was higher in large cities than provinces and increased 2-3 times in 2011 compared with 2007 in all regions. CONCLUSIONS: There was no significant difference in the number of open surgeries for the 5-year study, but the number of percutaneous procedures (nerve blocks) increased each year, showing an approximate 4-fold increase in 4 years. Lumbar infection showed a positive correlation with percutaneous procedures, and kyphoplasty and open surgeries were negatively correlated. Therefore, as selective nerve block procedure is also considered an important factor affecting the growing trend of lumbar infections, unnecessary procedures should be avoided to reduce the absolute number of infections.

Standards of practice: quality assurance guidelines for percutaneous treatments of intervertebral discs.

Percutaneous treatments are used in the therapy of small- to medium-sized hernias of intervertebral discs to reduce the intradiscal pressure in the nucleus and theoretically create space for the herniated fragment to implode inward, thus reducing pain and improving mobility and quality of life. These techniques involve the percutaneous removal of the nucleus pulposus by using a variety of chemical, thermal, or mechanical techniques and consist of removal of all or part of nucleus pulposus to induce more rapid healing of the abnormal lumbar disc. These guidelines are written to be used in quality improvement programs for assessing fluoroscopy- and/or computed tomography-guided percutaneous intervertebral disc ablative techniques.

Comprehensive evidence-based guidelines for interventional techniques in the management of chronic spinal pain.

BACKGROUND: Comprehensive, evidence-based guidelines for interventional techniques in the management of chronic spinal pain are described here to provide recommendations for clinicians. OBJECTIVE: To develop evidence-based clinical practice guidelines for interventional techniques in the diagnosis and treatment of chronic spinal pain. DESIGN: Systematic assessment of the literature. METHODS: Strength of evidence was assessed by the U.S. Preventive Services Task Force (USPSTF) criteria utilizing 5 levels of evidence ranging from Level I to III with 3 subcategories in Level II. OUTCOMES: Short-term pain relief was defined as relief lasting at least 6 months and long-term relief was defined as longer than 6 months, except for intradiscal therapies, mechanical disc decompression, spinal cord stimulation and intrathecal infusion systems, wherein up to one year relief was considered as short-term. RESULTS: The indicated evidence for accuracy of diagnostic facet joint nerve blocks is Level I or II-1 in the diagnosis of lumbar, thoracic, and cervical facet joint pain. The evidence for lumbar and cervical provocation discography and sacroiliac joint injections is Level II-2, whereas it is Level II-3 for thoracic provocation discography. The indicated evidence for therapeutic interventions is Level I for caudal epidural steroid injections in managing disc herniation or radiculitis, and discogenic pain without disc herniation or radiculitis. The evidence is Level I or II-1 for percutaneous adhesiolysis in management of pain secondary to post-lumbar surgery syndrome. The evidence is Level II-1 or II-2 for therapeutic cervical, thoracic, and lumbar facet joint nerve blocks; for caudal epidural injections in managing pain of post-lumbar surgery syndrome, and lumbar spinal stenosis, for cervical interlaminar epidural injections in managing cervical pain (Level II-1); for lumbar transforaminal epidural injections; and spinal cord stimulation for post-lumbar surgery syndrome. The indicated evidence for intradiscal electrothermal therapy (IDET), mechanical disc decompression with automated percutaneous lumbar discectomy (APLD), and percutaneous lumbar laser discectomy (PLDD) is Level II-2. LIMITATIONS: The limitations of these guidelines include a continued paucity of the literature, lack of updates, and conflicts in preparation of systematic reviews and guidelines by various organizations. CONCLUSION: The indicated evidence for diagnostic and therapeutic interventions is variable from Level I to III. These guidelines include the evaluation of evidence for diagnostic and therapeutic procedures in managing chronic spinal pain and recommendations for managing spinal pain. However, these guidelines do not constitute inflexible treatment recommendations. Further, these guidelines also do not represent "standard of care."

Automated percutaneous lumbar discectomy for the contained herniated lumbar disc: a systematic assessment of evidence.

BACKGROUND: Lumbar disc prolapse, protrusion, and extrusion account for less than 5% of all low back problems, but are the most common causes of nerve root pain and surgical interventions. The typical rationale for traditional surgery is an effort to provide more rapid relief of pain and disability. It should be noted that the majority of patients will recover with conservative management. The primary rationale for any form of surgery for disc prolapse associated with radicular pain is to relieve nerve root irritation or compression due to herniated disc material. The primary modality of treatment continues to be either open or microdiscectomy, but several alternative techniques including automated percutaneous lumbar discectomy (APLD) have been described. However, there is a paucity of evidence for all decompression techniques, specifically alternative techniques including automated and laser discectomy. STUDY DESIGN: A systematic review of the literature. OBJECTIVE: To determine the effectiveness of APLD. METHODS: A comprehensive evaluation of the literature relating to automated lumbar disc decompression was performed. The literature was evaluated according to Cochrane review criteria for randomized controlled trials (RCTs), and Agency for Healthcare Research and Quality (AHRQ) criteria was utilized for observational studies. A literature search was conducted of English language literature through PubMed, EMBASE, the Cochrane library, systematic reviews, and cross references from reviews and systematic reviews. The level of evidence was classified as Level I, II, or III with 3 subcategories in Level II based on the quality of evidence developed by the United States Preventive Services Task Force (USPSTF). OUTCOME MEASURES: Pain relief was the primary outcome measure. Other outcome measures were functional improvement, improvement of psychological status, opioid intake, and return to work. Short-term effectiveness was defined as one year or less, whereas, long-term effectiveness was defined as greater than one year. RESULTS: Based on USPSTF criteria, the indicated evidence for APLD is Level II-2 for short- and long-term relief. LIMITATIONS: Paucity of RCTs in the literature. CONCLUSION: This systematic review indicated Level II-2 evidence for APLD. APLD may provide appropriate relief in properly selected patients with contained lumbar disc prolapse.

An evaluation of image-guided technologies in the placement of percutaneous iliosacral screws.

STUDY DESIGN: A surgical simulation study in human cadaver spine specimens was conducted to evaluate the accuracy of 3 different surgical navigation systems compared to standard fluoroscopy in the percutaneous placement of iliosacral screws. OBJECTIVES: To compare the accuracy of percutaneous iliosacral screw placement using standard fluoroscopy, computer-assisted fluoroscopic image guidance, Iso-C3D image guidance (Medtronic Surgical Navigation Technologies, Louisville, CO), and electromagnetic fluoroscopic image guidance. SUMMARY OF BACKGROUND DATA: Conventional percutaneous sacroiliac screw placement has a malposition rate as high as 15%, as reported in the English-speaking literature (Hinsche et al [Clin Orthop Relat Res 2002;395:135-44] and Templeman et al [Clin Orthop Relat Res 1996;329:194-8]). Iso-C3D and computer-assisted image guidance technologies have been proposed to increase this accuracy rate. METHODS: Two iliosacral screws were placed bilaterally (4 screws) in each of 4 cadavers using standard fluoroscopy, computer-assisted fluoroscopic image guidance, Iso-C3D image guidance, and electromagnetic fluoroscopic image guidance. Screw positions were analyzed by computerized tomography after instrumentation and assigned a score based on deviation from ideal screw position. RESULTS: The StealthStation with FluoroNav (Medtronic Surgical Navigation Technologies) appeared to provide the highest accuracy of all guidance techniques. This result was more accurate than standard fluoroscopy. CONCLUSIONS: Computer-assisted fluoroscopy based image navigation appears to be more accurate than standard fluoroscopy in placing these screws. However, errors may occur with all techniques. Further refinement in registration procedures may highly improve the accuracy of percutaneous screw placement in a variety of spinopelvic procedures.

Morphometric analysis of the working zone for endoscopic lumbar discectomy.

OBJECTIVE: Our study's purpose was to analyze the working zone for the current practice of endoscopic discectomy at the lateral exit zone of the intervertebral foramen (IVF) and to define a safe point for clinical practice. METHODS: One hundred eighty-six nerve roots of the lumbar IVFs of cadaveric spines were studied. Upon lateral inspection, we measured the distance from the nerve root to the most dorsolateral margin of the disc and to the lateral edge of the superior articular process of the vertebra below at the plane of the superior endplate of the vertebra below. The angle between the root and the plane of the disc was also measured. RESULTS: The results showed that the mean distance from the nerve root to the most dorsolateral margin of the disc was 3.4 +/- 2.7 mm (range 0.0-10.8 mm), the mean distance from the nerve root to the lateral edge of the superior articular process of the vertebra below was 11.6 +/- 4.6 mm (range 4.1-24.3 mm), and the mean angle between the nerve root and the plane of the disc was 79.1 degrees +/- 7.6 degrees (range 56.0-90.0 degrees ). CONCLUSIONS: The values of the base of the working zone have a wide distribution. Blind puncture of annulus by the working cannula or obturator may be dangerous. The safer procedure would be the direct viewing of the annulus by endoscopy before annulotomy; the working cannula should be inserted into the foramen as close as possible to the facet joint.

Endoscopic transforaminal lumbar discectomy and reconfiguration: a postero-lateral approach into the spinal canal.

BACKGROUND: In the past, minimally invasive procedures (chemonucleolysis, laser, automated percutaneous discectomy, percutaneous manual nucleotomy, arthroscopy) have been largely confined to intradiscal work. This study represents cases of working channel, transforaminal spinal endoscopy performed using an endoscope which, because of its small size and flexibility, can bend up to 90 degrees (depending on the guiding cannula), and pass completely through the foramen into the spinal canal (truly transforaminal, as opposed to just going through part of the foramen and into the disc), to directly remove free fragments and reconfigure disc, relieving root and dural displacement at all lumbar levels. METHODS: The records of 533 patients who had outpatient, minimally invasive operations performed over a 6-year period (ending in 1995) by this author were analyzed. Of these, 110 had small scope transforaminal procedures, forming the basis of this study. RESULTS: An independent observer followed the 110 patients who had endoscopic transforaminal procedures for 2 or more years. Using MacNab's criteria, the success rate (excellent or good) was 95% in the 75 patients with disc presenting lateral to the dura-"lateral presenting,"-and 83% in the 35 patients not presenting disc for direct removal-"non-lateral presenting" (i.e., dura in the pathway)-making an overall success rate of 91%. One patient who developed discitis was the only complication. CONCLUSION: Guideable endoscopes small enough to pass completely through the foramen allow percutaneous surgery to include non-contained disc herniations and even some migrated free fragments, depending on the location. The percutaneous transforaminal endoscopic technique can be an effective, safe approach for disc removal through the foramen, especially in cases where the disc presents itself for direct removal.

Long-term outcome of patients who underwent percutaneous nucleotomy for lumbar disc herniation: results after a mean follow-up of 5 years.

A total of 41 patients who had undergone percutaneous nucleotomy for a single level lumbar disc herniation were clinically examined after a mean postoperative follow-up of 5 years (range 4 to 7 years). There were 14 (34%) male and 27 (66%) female patients with a mean age of 49 years. By intra-operative discography, the herniation had been graded as a protrusion in 21 (51%) patients and as a prolapse in 20 (49%) patients. At the time of the investigation, sciatica had completely recovered or markedly diminished in 32 (78%) patients, and 29 (71%) patients had returned to work. Evaluated by a 100 mm visual analog pain scale (VAS), the postoperative pain relief was statistically significant (p < 0.0001). Clinical signs and symptoms of segmental instability of the lumbar spine were detected in 10 (24%) patients. Instability was significantly associated with an unsatisfactory long-term outcome in the patients with the occurrence of sciatica (p = 0.003) and low back pain (p = 0.001) as well as the VAS score (p = 0.005) and Oswestry index (p < 0.0001). Clinical investigation revealed sensory deficits in the leg in 12 (29%) patients, weakness of the extensor hallucis longus muscle in 5 (12%) patients and a total peroneal paresis in one (2%). The patellar and achilles tendon reflexes were depressed in 2 (5%) and 5 (12%) patients, respectively. During the follow-up period, recurrent disc herniation was detected in 3 (7%) patients who were all re-operated on. In addition, 3 (7%) patients were re-operated on for other back problems. Corroborating earlier findings, the results of this study indicate that percutaneous nucleotomy is an effective and safe alternative to open surgery in the treatment of patients with a small prolapse or a protrusion.