Comparison of microendoscopic discectomy and open discectomy for single-segment lumbar disc herniation

BACKGROUND Lumbar disc herniation is a common disease.Endoscopic treatment may have more advantages than traditional surgery.AIM To compare the clinical efficacy and safety of microendoscopic discectomy(MED)and open discectomy with lamina nucleus enucleation in the treatment of singlesegment lumbar intervertebral disc herniation.METHODS Ninety-six patients who were operated at our hospital were selected for this study.Patients with single-segment lumbar disc herniation were admitted to the hospital from March 2018 to March 2019 and were randomly divided into the observation group and the control group with 48 cases in each group.The former group underwent lumbar discectomy and the latter underwent laparotomy and nucleus pulpectomy.Surgical effects were compared between the two groups.RESULTS In terms of surgical indicators,the observation group had a longer operation time,shorter postoperative bedtime and hospital stay,less intraoperative blood loss,and smaller incision length than the control group(P<0.05).The excellent recovery rate did not differ significantly between the observation group(93.75%)and the control group(91.67%).Visual analogue scale pain scores were significantly lower in the observation group than in the control group at 1 d,3 d,1 mo,and 6 mo after surgery(P<0.05).The incidence of complications was significantly lower in the observation group than in the control group(6.25%vs 22.92%,P<0.05).CONCLUSION Both MED and open discectomy can effectively improve single-segment lumbar disc herniation,but MED is associated with less trauma,less bleeding,and a lower incidence of complications.

Transforaminal Percutaneous Endoscopic Discectomy using Transforaminal Endoscopic Spine System technique: Pitfalls that a beginner should avoid

Transforaminal Percutaneous Endoscopic Discectomy(TPED) is a minimally invasive technique mainly used for the treatment of lumbar disc herniation from a lateral approach. Performed under local anesthesia, TPED has been proven to be a safe and effective technique which has been also associated with shorter rehabilitation period, reduced blood loss, trauma, and scar tissue compared to conventional procedures. However, the procedure should be performed by a spine surgeon experienced in the specific technique and capable of recognizing or avoiding various challenging conditions. In this review, pitfalls that a novice surgeon has to be mindful of, are reported and analyzed.

Ultrasound guidance for transforaminal percutaneous endoscopic lumbar discectomy may prevent radiation exposure: A case report

BACKGROUND Percutaneous endoscopic lumbar discectomy(PELD)has become a mature and mainstream minimally invasive surgical technique for treating lumbar disc herniation(LDH).Repeated fluoroscopy,with more than 30 shots on average,is inevitable to ensure its accuracy and safety.However,exposure to X-rays may pose a threat to human health.We herein report a case of ultrasound(US)-assisted PELD in two levels of LDH to explore a new possibility that can reduce the radiation dose during puncture and cannulation in PELD.CASE SUMMARY A 38-year-old man with low back pain and left leg pain for more than 7 years came to our clinic,his symptoms had aggravated for 1 month,and he was diagnosed with L3-4 and L4-5 disc herniations.He received US-guided PELD with good results:His straight leg elevation increased from 40 to 90 degrees after PELD,and his visual analog scale(VAS)and Oswestry Disability Index scores both significantly decreased immediately and 6 mo after PELD.With the guidance of US,he received only two shots of fluoroscopy(fluoroscopic time:4.4 s;radiation dose:3.98 mGy).To our knowledge,this is the first case of US-guided puncture and cannulation of PELD for LDH at two levels.CONCLUSION US could be used to guide PELD and has the potential to largely reduce radiation than traditional X-ray guidance.

Technique of Percutaneous Transforaminal Endoscopic Discectomy for the Treatment of Lumbar Disc Herniation

Percutaneous Transforaminal Endoscopic Discectomy is a minimally invasive surgery with little pain, less blood loss, less hospital stay and the surgery can be done in local anesthesia, which was started during late 20th century. Kambin and Gellmann in 1973 in the United States and Hijikata in Japanin 1977 individually preformed posterolateral percutaneous nucleotomy for the resection of the nucleus pulposus and release of compressed exiting nerve root, which is now spreading through the world and many surgeons are developing their skill but it needs experience and patience for successful outcomes. Along with advanced instruments now the surgery can be performed only giving a small skin incision of 8 - 10 mm and is as effective as the conventional method of surgery and open microdiscectomy surgery for the treatment of symptomatic lumbar disc herniation. In this review, we are explaining the technique of minimally invasive Percutaneous Transforaminal Endoscopic Discectomy surgery along its advantages and complications which can be encountered while performing this technique.

Two-level percutaneous endoscopic lumbar discectomy for highly migrated upper lumbar disc herniation: A case report

BACKGROUND The technique of percutaneous endoscopic lumbar discectomy(PELD)as a transforaminal approach has been used to treat highly migrated lower lumbar disc herniations.However,due to the different anatomic characteristics of the upper lumbar spine,conventional transforaminal PELD may fail to remove the highly migrated upper lumbar disc nucleus pulposus.Therefore,the purpose of this study was to describe a novel surgical technique,two-level PELD,for the treatment of highly migrated upper lumbar disc herniations and to report its related clinical outcomes.CASE SUMMARY A 60-year-old male presented with a complaint of pain at his lower back and right lower limb.The patient received 3 mo of conservative treatments but the symptoms were not alleviated.Physical examination revealed a positive femoral nerve stretch test and a negative straight leg raise test for the right leg,and preoperative visual analog scale(VAS)score for the lower back was 6 points and for the right leg was 8 points.Magnetic resonance imaging(MRI)demonstrated L2-L3 disc herniation on the right side and the herniated nucleus pulposus migrated to the upper margin of L2 vertebral body.According to physical examination and imaging findings,surgery was the primary consideration.Therefore,the patient underwent surgical treatment with two-level PELD.The pain symptom was relieved and the VAS score for back and thigh pain was one point postoperatively.The patient was asymptomatic and follow-up MRI scan 1 year after operation revealed no residual nucleus pulposus.CONCLUSION Two-level PELD as a transforaminal approach can be a safe and effective procedure for highly migrated upper lumbar disc herniation.

Outcomes of cervical degenerative disc disease treated by anterior cervical discectomy and fusion with self-locking fusion cage

BACKGROUND Cervical degenerative disc(CDD)disease is a common type of spondylosis.Although anterior cervical discectomy and fusion(ACDF)is the preferred treatment for CDD disease,internal fixation with a titanium plate may cause various complications.The invention of the ACDF with a self-locking fusion cage(ROI-C)has effectively decreased the incidence of postoperative complications.AIM To observe the outcomes of CDD disease treated by ACDF with a ROI-C.METHODS Ninety patients with CDD disease treated at our hospital from March 2019 to March 2021 were included.They were divided into two groups(control group and observation group,n=45 in each)using a random number table.Patients in the control group received ACDF plus internal fixation with a titanium plate.Those in the observation group received ACDF+ROI-C placement.The two groups of patients were compared in terms of surgical parameters,pain,cervical spine function,range of motion,and complications.RESULTS The two groups of patients showed no significant differences in surgical time,blood loss,drainage volume,and length of hospital stay(P>0.05).No significant differences in the visual analogue scale(VAS),Japanese Orthopedic Association(JOA),and neck disability index(NDI)scores were observed between the two groups before surgery(P>0.05).The VAS and NDI scores in the observation group were considerably lower than those in the control group after surgery;however,the JOA scores in the observation group were significantly higher than those in the control group(P<0.05).No significant differences were observed in cervical disc height and the range of motion of the superior or inferior adjacent vertebrae between the two groups before surgery(P>0.05).The disc height in the observation group was larger than that in the control group after surgery.The range of motion of both the superior and inferior adjacent vertebrae was significantly smaller in the observation group than in the control group(P<0.05).The incidence of complications was only 2.22% in the observation group compared to 15.56% in the control group,and the difference was statistically significant(P<0.05).CONCLUSION Cervical spine function restoration was better with ROI-C with internal fixation in ACDF than with conventional titanium plates in ACDF for CDD disease.

The Clinical Effect of Percutaneous Transforaminal Endoscopic Discectomy in the Treatment of Low Lumbar Single Segment Disc Herniation

Objective: To observe the clinical effect percutaneous transforaminal endoscopic discectomy (PTED) in the treatment of single lumbar disc herniation. Methods: From August 2017 to June 2019, 42 patients with low lumbar single segment lumbar disc herniation were treated with percutaneous transforaminal endoscopic discectomy surgery in our hospital. The operation time, incision size, bleeding volume and hospitalization time were recorded respectively. The patients were evaluated before operation, 1 month and 6 months after operation. Visual analogue scale (VAS) and assessment were used to evaluate the lumbocrural pain. The JOA score and the Oswestry disability index (ODI) were used to evaluate the lumbar function, and the modified macnab score was used to evaluate the clinical effect in the last follow-up. Results: All the 42 patients successfully completed the operation without any other operation. There were no severe complications such as dural injury and nerve root injury. The operation time was (76.98 ± 8.58) min, the incision size was (8.45 ± 1.2) mm, the bleeding volume was (20.14 ± 2.93) ml, and the hospitalization time was (4.55 ± 1.13) d. One month and six months after the operation, the visual analogue scale (VAS), the evaluation of lumbar function (Oswestry) and the disability index (ODI) were significantly improved compared with those before the operation (P Conclusion: The treatment of low lumbar but segmental lumbar disc herniation with percutaneous intervertebral foramen, with small incision, less bleeding and quick recovery, can improve the pain and dysfunction of patients.

Optimal approach for total endoscopic discectomy and its effect on lumbar and leg function in patients with disc herniation

BACKGROUND Disc herniation(DH)is a fragment of the disc nucleus that is pushed out of the annulus into the spinal canal due to a tear or rupture in the annulus.It is a common cause of lumbar and leg pains.Substantial advancements have been made to determine the cause of DH and to ensure accurate diagnosis,imaging,and treatment of this condition.Total endoscopic discectomy is an alternative surgical technique that is less invasive.AIM To study the optimal approach for a total endoscopic discectomy and its influence on lumbar and leg function in DH patients.METHODS This prospective study enrolled 120 patients with lumbar DH who were treated in our hospital from February 2018 to January 2021.All patients were randomly divided into the following two groups:The observation group,comprising 62 patients who underwent surgery using the interlaminar approach,and the control group,comprising 58 patients who were operated through the foramina approach.The treatment effects,perioperative indicators,functional recovery,pain,and quality of life were compared between the two groups.RESULTS The treatment effect in the observation group(93.55%)was significantly better than that in the control group(77.59%).There was no difference in the operative time and intraoperative blood loss amount between the two groups(P>0.05).The hospitalization time of the observation group(4.34±1.33 d)was significantly shorter than that of the control group(5.38±1.57 days)(P<0.05).The Japanese Orthopaedic Association and Oswestry Disability Index scores decreased significantly in both groups after treatment,but the scores were lower in the observation group than in the control group.The visual analog scale scores of the lower back and legs of the two groups were significantly reduced after treatment,but scores were lower in the observation group(2.18±0.88 in the lower back and 1.42±0.50 in the leg)than in the control group(3.53±0.50 in the lower back and 2.21±0.52 in the leg).A short form of the Arthritis Impact Measurement Scales 2 measurement scale(AIMS2-SF)score and Barthel index of the lower back of the two groups increased significantly after treatment,with the observation group having a significantly higher AIMS2-SF score(95.16±1.74)and Barthel index(97.29±1.75)than the control group(84.95±2.14 and 89.16±2.71,respectively)(P<0.05).CONCLUSION Through total endoscopic discectomy with the interlaminar approach,the degree of pain in the waist and leg was reduced,and the lumbar function considerably recovered.

Segmental artery injury during transforaminal percutaneous endoscopic lumbar discectomy:Two case reports

BACKGROUND Since Kambin experimentally induced arthroscopy to treat herniated nucleus pulposus,percutaneous endoscopic lumbar discectomy(PELD)has been developed.The branch of the segmental artery around the neural foramen may be damaged during PELD using the transforaminal approach.We report 2 rare cases in which segmental artery injury that occurred during PELD was treated with emergency embolization.CASE SUMMARY In case 1,a 31-year-old man was transferred to our emergency department with left lower quadrant abdominal pain after PELD at a local hospital.Lumbar spine magnetic resonance imaging after the surgery showed a hematoma of the left retroperitoneal area and the psoas muscle area.Under suspicion of vascular injury,arteriography was performed.Pseudoaneurysm and blood leakage from the left 4th lumbar segmental artery into the abdominal cavity were identified.Emergency transarterial embolization was performed using fibered microcoils for bleeding of the segmental artery.In case 2,a 75-year-old woman was transferred to our emergency department with low blood pressure,right flank pain,and drowsy mental status after PELD at a local hospital.When the patient arrived at the emergency room,the blood pressure decreased from 107/55 mmHg to 72/47 mmHg.Low blood pressure persisted.Under suspicion of vessel injury,arteriography was performed,and the right 4th lumbar segmental artery rupture was confirmed.Emergency transarterial embolization was performed for bleeding of segmental artery.CONCLUSION We were able to find the bleeding focus by angiography and treat the injury of the segmental artery successfully through emergency transarterial embolization.

Anterior Discectomy and Fusion versus Posterior Foraminotomy in Treatment of Cervical Radiculopathy: A Comparative Prospective Study

Introduction: Cervical radiculopathy is caused by either cervical disc herniation or bone spurs due to cervical spine degeneration. It is common in middle aged and elderly patients. Those patients who are refractory to conservative treatment are candidates for surgical management. The surgical approaches for cervical radiculopathy are either anterior cervical discectomy and fusion (ACDF) or posterior cervical foraminotomy (PCF). In spite of many reports on ACDF and PCF, only a few studies directly compare the outcomes of both techniques. Purpose: To compare anterior cervical discectomy and fusion (ACDF) with posterior cervical foraminotomy (PCF) for the treatment of cervical radiculopathy, regarding the surgical, clinical and radiological outcomes. Patient and methods: This is a prospective randomized controlled clinical study carried on 44 patients with unilateral cervical radiculopathy. They are divided into 2 groups;group (A) included 23 patients who underwent ACDF and group (B) included 21 patients who underwent PCF, with 1 year follow up. The patient age, sex, clinical manifestations, surgical outcomes as number of cervical level, operative time, blood loss, complications and length of hospital stay were recorded. Visual analogus scale (VAS) and neck disability index (NDI) were used for evaluation of clinical outcomes. Postoperative imaging was done after 1 year to detect instability or adjacent level degeneration. Chi-square and unpaired T-test were used to compare the mean values of both groups. Results: The mean age was nearly 45 years for both groups. C5-6 ACDF was the most common level in group (A), while C6-7 PCF was the most frequent operated level in group (B). PCF group had less operative time, blood loss and length of hospital stay than ACDF group. Clinical improvement of the mean values of VAS and NDI were more pronounced in PCF group as compared to ACDF group with statistically significant difference. No cases of cervical instability were recorded during the period of follow up. Conclusion: Posterior cervical foraminotomy is a safe and effective technique for the treatment of cervical radiculopathy as compared to anterior cervical discectomy and fusion. PCF has a shorter operative time, less hospital stay and better clinical outcome.

Comparison of pain media and inflammatory factors after percutaneous transforaminal endoscopic discectomy and traditional fenestration operation treatment of protrusion of lumbar intervertebral disc

Objective:To compare the differences in pain mediators and inflammatory factors after percutaneous transforaminal endoscopic discectomy and traditional fenestration operation treatment of protrusion of lumbar intervertebral disc. Methods:80 patients with protrusion of lumbar intervertebral disc treated in our hospital between March 2013 and December 2015 were collected and divided into observation group and control group (n=40) according to randomized parallel contrast. Control group received traditional fenestration operation and observation group received percutaneous transforaminal endoscopic discectomy. Before operation and 1 week after operation, fluorescence spectrophotometry was used to determine serum pain medium levels;ELISA was used to determine pro-inflammatory factor and anti-inflammatory factor levels. Results:Before operation, differences in serum pain medium and inflammatory factor levels were not statistically significant between two groups (P>0.05). 1 week after operation, serum pain media norepinephrine (NE), dopamine (DA), 5-hydroxytryptamine (5-HT), prostaglandin E2 (PGE2) and substance P (SP) levels as well as pro-inflammatory factors interleukin-1β(IL-1β), interleukin-6 (IL-6), interleukin-18 (IL-18) and tumor necrosis factor alpha (TNF-α) levels of observation group were lower than those of control group (P<0.05) while serum anti-inflammatory factors interleukin-4 (IL-4), interleukin 10 (IL-10), soluble tumor necrosis factor receptor I (sTNF-RI) levels were higher than those of control group (P<0.05). Conclusions:Percutaneous transforaminal endoscopic discectomy can effectively treat protrusion of lumbar intervertebral disc and is more advantageous in alleviating patients’ perception of pain and reducing inflammation.

CLINICAL STUDY OF ACUPUNCTURE-DRUG COMBINED ANESTHESIA FOR ANTERIOR APPROACH CERVICAL DISCECTOMY

The study compared the anesthetic effects between acupuncture-drug combined anes-thesia and local anesthetic-drug combined anesthesia for anterior approach cervical discectomy. Theresults demostrated that the analgesic effects have no difference between these two groups. Theacupuncture-drug combined anesthesia group had less postoperative complication, sooner recovery andbetter social and economic benefits. The method is worth using widely in clinical practice.

Microendoscopic discectomy for treatment of lumbar disc herniation

A lumbar microendoscopic discectomy(MED)is a minimally invasive surgical technique performed through a tubular device which is designed for the pain relieve caused by herniated discs pressing the nerve roots.In 1997,a new minimally invasive surgical approach for the management of symptomatic lumbar disc herniation,MED was introduced.This technique uses a tubular retractor system and a microendoscope for visualization rather than the operating microscope.However,recent literature suggests that MED is an effective microendoscopic system which has a fine long-term outcome in treating lumbar disc herniation.This article describes the operative techniques and outcomes reported in the literature for MED.

Delayed massive cerebral infarction after perioperative period of anterior cervical discectomy and fusion:A case report

BACKGROUND Cerebral infarction is an extremely rare postoperative complication of anterior cervical discectomy and fusion(ACDF),particularly in the delayed setting.We present a case who had a sudden stroke on day 18 after surgery.By sharing our experience with this case,we hope to provide new information about stroke after anterior cervical surgery.CASE SUMMARY We present the case of a 61-year-old man with more than 20 years of hypertension and 14 years of coronary heart disease who had suffered a stroke 11 years ago.The patient was admitted for a multiple ACDF due to symptoms of cervical spondylotic myelopathy and had a sudden stroke on day 18 after surgery.Imaging findings showed a large-area infarct of his left cerebral hemisphere and thrombosis in his left common carotid artery.With the consent of his family,the thrombus was removed and a vascular stent was implanted through an interventional operation.Forty days later,the patient was transferred to a rehabilitation hospital for further treatment.He had normal consciousness but slurred speech at the 1-year follow-up evaluation.The motor and sensory functions of his hemiplegic limbs partially recovered.CONCLUSION This case illustrated that a postoperative stroke related to anterior cervical surgery may be attributed to prolonged carotid retraction and might have a long silent period.Preventive measures include careful preoperative and postoperative examination for high-risk patients as well as gentle and intermittent retraction of carotid artery sheath during operation.

The Endplate Morphology Changes with Change in Biomechanical Environment Following Discectomy

Bone is a dynamic structure and is known to respond to changes in the load over time, in accordance with Wolff’s law. It states that the bone changes its shape and internal architecture in response to stresses acting on it [1]. Therefore, any structural changes in the spine may lead to bone remodeling due to changes in the optimal stress pattern. The changes in apparent density and thickness of the endplates following discectomy of varying amounts were analyzed. The study design coupled a bone remodeling algorithm based on strain energy density theory of adaptive remodeling with an experimentally validated 3D ligamentous finite element model of the spine. The apparent density and thickness of the index level endplates decreased above and below the region of discectomy. On the other hand, these parameters showed increases at the remaining regions of the endplate. There were no correlations between the amount of nucleus removed and the average percentage changes in apparent density and thickness of endplate above and below the discectomy region. However, the average percentage changes in apparent density and thickness at endplate in the other region increased with increase in amount of nucleus removed. These predictions are in agreement with the clinical observations [2-6].

Conventional versus minimally-invasive cervical discectomy for treatment of severe degenerative disease at C5-C6: a biomechanical comparison using a model of the full cervical spine and finite element analysis

The purpose of this study was to determine the dif-ferences in biomechanical responses of tissues in the cervical spine when pain and other problems secon-dary to severe disc degeneration disease are surgi-cally treated by conventional discectomy (CONDIS) compared to minimally-invasive discectomy (MIVDIS). A validated three-dimensional model of an intact, healthy, adult full cervical spine (C1-C7) (INT) was constructed. This model was then modified to create two models, one simulating each of the above-men-tioned two techniques for discectomy of the severely degenerated C5-C6 disc. For each of these three models, we used the finite element analysis method to obtain three biomechanical parameters at various tissues in the model, under seven different physio-logically relevant loadings. For each of the biome-chanical parameters, the results were expressed as relative change in its value when a specified combi-nation of simulated discectomy model and applied loading was used, with respect to the corresponding value in the intact model. We then computed the value of a composite biomechanical performance in-dex (CBPI) for CONDIS and MIVDIS models, with this value incorporating all of the aforementioned relative changes. We found that CBPI was marginally lower for MIVDIS model. This trend is the same as that reported for the relative complications rate and outcome measures following conventional and mini-mally-invasive discectomies in the lumbar spine. From a healthcare perspective, one implication of our finding is that minimally-invasive cervical discectomy should be considered an attractive option provided that detailed patient selection criteria are clearly de-fined and strictly followed.

Comparison of the pain and inflammatory stress after percutaneous transforaminal endoscope discectomy and open fenestration discectomy

Objective:To study the differences in pain and inflammatory stress after percutaneous transforaminal endoscope discectomy and open fenestration discectomy.Methods: Patients with lumbar intervertebral disc herniation who underwent surgical treatment in our hospital between January 2013 and January 2017 were selected and randomly divided into two groups: Percutaneous transforaminal endoscope discectomy (PTED) group and control group. Patients in PTED group received percutaneous transforaminal endoscope discectomy, while control group received open fenestration discectomy. Serum levels of pain substances SP, NPY, PGE2 and NGF, inflammatory mediators IFN-γ, TNF-α, IL-17 and MMP3 as well as stress response substances Cor, NE, OH-, O2- and MDA of two groups of patients were determined the same day after surgery and 3 days after surgery.Results: The same day after surgery and 3 d after surgery, serum SP, NPY, PGE2, NGF, IFN-γ, TNF-α, IL-17, MMP3, Cor, NE, OH-, O2- and MDA levels of PTED group were significantly lower than those of control group. Conclusion: Percutaneous transforaminal endoscope discectomy for lumbar intervertebral disc herniation causes less postoperative pain and inflammatory stress than open fenestration discectomy.

Percutaneous Endoscopic Lumbar Discectomy versus Conventional Open Discectomy: A Prospective Randomized Comparative Trial

Introduction: The majority of series considered the conventional open discectomy as the gold standard for the treatment of lumbar disc prolapse. Despite of the popularity of the lumbar endoscopic discectomy nowadays, many neurosurgeons still prefer conventional open discectomy. Purpose: Our study has been designed to compare between percutaneous endoscopic lumbar discectomy and conventional open discectomy;regarding surgical results, complications, clinical and functional outcomes. Patients and Methods: This study is a clinical prospective randomized controlled trial conducted upon 30 patients suffering from prolapsed lumbar disc, from December 2016 to May 2018. Those patients were divided randomly into 2 groups, 15 patients each. One group treated by percutaneous endoscopic interlaminar lumbar discectomy (PELD) and the other group treated by conventional open discectomy (COD). Operative time, wound size, Intraoperative blood loss, Intraoperative complications, postoperative hospital stay, Postoperative complication and the results of visual analogue score (VAS) and modified MacNab’s criteria were assessed. Results: This study included 30 patients (18 males and 12 females). The mean age was about 35 years. Although, there was postoperative improvement of the VAS and MacNab’s criteria in the two groups, there was no statistically significant difference between the preoperative and postoperative VAS of low back pain and radicular pain for the two groups in the follow up period. Conclusion: Both techniques give good results for patients;each technique has some advantages over the other.

Comparison of nerve conduction and injury degree in patients with lumbar disc herniation after microendoscopic discectomy and fenestration discectomy

Objective: To study the difference of nerve conduction and injury degree in patients with lumbar disc herniation after microendoscopic discectomy and fenestration discectomy. Methods: Patients with single-segment lumbar disc herniation who were treated in Dazhou Central Hospital between May 2014 and February 2017 were selected as the research subjects, the history data were reviewed and the operation methods were referred to divide them into FD group and MED group who received fenestration discectomy and microendoscopic discectomy respectively. The conduction velocity of common peroneal nerve and tibial nerve were detected before operation and 4 weeks after operation;serum levels of nerve and muscle injury-related molecules as well as inflammation and stress-related molecules were detected before operation and 3 days after operation. Results: MNCV levels of common peroneal nerve and tibial nerve 4 weeks after operation as well as serum CRP, TNF-α, MDA and AOPP contents 3 d after operation of both groups of patients were significantly higher than those before operation, and the MNCV levels of common peroneal nerve and tibial nerve of MED group 4 weeks after operation were significantly higher than those of FD group while serum CRP, TNF-α, MDA and AOPP contents of MED group 3 d after operation were not significantly different from those of FD group;serum NSE, S100B, Tau, pNF-H, CPK, Myo and LDH contents of FD patients 3 d after operation were significantly higher than those before operation while serum NSE, S100B, Tau, pNF-H, CPK, Myo and LDH contents of MED group were not significantly different from those before operation. Conclusion: Microendoscopic discectomy for lumbar disc herniation can relieve the nerve and muscle injury, and is equivalent to fenestration discectomy in activating the systemic stress and inflammatory response.

LONG-TERM OUTCOMES OF FENESTRATED DISCECTOMY FOR LUMBAR DISC

Objective To evaluate the long-term outcomes of fenestrated discectomy for lumbar disc herniation and analyze the correlative influence factors. Methods Eighty-two cases of lumbar disc herniation, from February 1996 to May 1999, were retrospectively studied. All patients were treated with simple fenestrated discectomy. The average follow-up time was 8 years and 7 months （from 7 years tolO years and 3months）. There were 13, 38 and 31 cases at 13 - L4, L4 - L5 and L5 - S1 level, respectively. Results The average scales before operation were as following ： Japanes Orthopaedics Association （ JOA ） scale 6. 5 （ 5 - 9 ） , visual analysis scale （ VAS） of low back pain4.8 （0-8）. and VAS of sciatica 7.2 （4-10）. At the final follow-up, the above parameters were 13.2 （ 10 - 14 ）, 1.8 （0 - 10） and 1.2 （0 - 7）, respectively. The average increase ratio of JOA scale was 78. 8%. The average disc-vertebra height ratio （ Mochida method） was 80.2%. At the final follow-up, 7 cases reoccurred disc herniation. The final clinical satisfaction rate was 80% （ modified Macnab method ）. Conclusion With appropriate surgical indications, the successfid long-term outcomes could be expected with fenestrated discectomy. Discectomy improves sciatica to a greater extent than low back pain. The occurrence of low back pain is related to intervertebral disc height, segment stability, disc degeneration, and lumbar muscle disability.