Risk factors and clinical significance of posterior slip of the proximal vertebral body after lower lumbar fusion

BACKGROUND Adjacent segment disease(ASD)after fusion surgery is frequently manifests as a cranial segment instability,disc herniation,spinal canal stenosis,spondylolisthesis or retrolisthesis.The risk factors and mechanisms of ASD have been widely discussed but never clearly defined.AIM To investigate the risk factors and clinical significance of retrograde movement of the proximal vertebral body after lower lumbar fusion.METHODS This was a retrospective analysis of the clinical data of patients who underwent transforaminal lumbar interbody fusion surgery between September 2015 and July 2021 and who were followed up for more than 2 years.Ninety-one patients with degenerative lumbar diseases were included(22 males and 69 females),with an average age of 52.3 years(40-73 years).According to whether there was retrograde movement of the adjacent vertebral body on postoperative X-rays,the patients were divided into retrograde and nonretrograde groups.The sagittal parameters of the spine and pelvis were evaluated before surgery,after surgery,and at the final follow-up.At the same time,the Oswestry Disability Index(ODI)and Visual Analogue Scale(VAS)were used to evaluate the patients’quality of life.RESULTS Nineteen patients(20.9%)who experienced retrograde movement of proximal adjacent segments were included in this study.The pelvic incidence(PI)of the patients in the retrograde group were significantly higher than those of the patients in the nonretrograde group before surgery,after surgery and at the final follow-up(P<0.05).There was no significant difference in lumbar lordosis(LL)between the two groups before the operation,but LL in the retrograde group was significantly greater than that in the nonretrograde group postoperatively and at the final follow-up.No significant differences were detected in terms of the|PI–LL|,and there was no significant difference in the preoperative lordosis distribution index(LDI)between the two groups.The LDIs of the retrograde group were 68.1%±11.5%and 67.2%±11.9%,respectively,which were significantly lower than those of the nonretrograde group(75.7%±10.4%and 74.3%±9.4%,respectively)(P<0.05).Moreover,the patients in the retrograde group had a greater incidence of a LDI<50%than those in the nonretrograde group(P<0.05).There were no significant differences in the ODI or VAS scores between the two groups before the operation,but the ODI and VAS scores in the retrograde group were significantly worse than those in the nonretrograde group after the operation and at the last follow-up,(P<0.05).CONCLUSION The incidence of posterior slippage after lower lumbar fusion was approximately 20.9%.The risk factors are related to a higher PI and distribution of lumbar lordosis.When a patient has a high PI and insufficient reconstruction of the lower lumbar spine,adjacent segment compensation via posterior vertebral body slippage is one of the factors that significantly affects surgical outcomes.

Full-endoscopic spine surgery treatment of lumbar foraminal stenosis after osteoporotic vertebral compression fractures:A case report

BACKGROUND Few reports have described lumbar foraminal stenosis-induced radiculopathy after treatment by full-endoscopic spine surgery(FESS)combined with percutaneous vertebroplasty(PVP)in patients with vertebral compression fractures.We herein report such a case,including the patient’s treatment process and doctor’s surgical experience.CASE SUMMARY A 79-year-old man presented with symptoms of radiculopathy after sustaining L4 vertebral compression fractures.Imaging and physical examination revealed L4 vertebral compression fractures combined with L3/4 Lumbar foraminal stenosis(LFS).The patient’s symptoms were low back pain with pain in the lateral left leg.Although many reports have described radiculopathy induced by osteoporotic vertebral compression fractures,the use of FESS combined with PVP has rarely been reported.This case report indicates that the combination of FESS and PVP is a safe and effective approach for the treatment of LFS-induced radiculopathy after vertebral compression fractures.This minimally invasive technique has great potential to replace traditional lumbar fixation and decompression surgery.Thus,we suggest the continued accumulation of similar cases to discuss the wider application of FESS.CONCLUSION For patients with osteoporotic vertebral compression fracture(OVCF)and LFS,PVP and FESS can be used to restore the vertebral height and reduce the pressure around the intervertebral foramen.Additionally,the combination of FESS and PVP can treat the pain or numbness of the low back and lower limbs and allow for recovery in a short time with excellent postoperative effects.In general,FESS is a good treatment for radiculopathy caused by foraminal stenosis after OVCF.

Methods of predicting vertebral body fractures of the lumbar spine

Lumbar vertebral body(VB) fractures are increasingly common in an ageing population that is at greater risk of osteoporosis and metastasis. This review aims to identify different models, as alternatives to bone mineral density(BMD), which may be applied in order to predict VB failure load and fracture risk. The most representative models are those that take account of normal spinal kinetics and assess the contribution of the cortical shell to vertebral strength. Overall, predictive models for VB fracture risk should encompass a range of important parameters including BMD, geometric measures and patient-specific factors. As interventions like vertebroplasty increase in popularity for VB fracture treatment and prevention, such models are likely to play a significant role in the clinical decision-making process. More biomechanical research is required, however, to reduce the risks of post-operative adjacent VB fractures.

Clinical Study of Applying Enhanced Recovery after Surgery Concept in Single-Segment Lumbar Spinal Stenosis Surgery

Objective: With the aging population and changes in lifestyle, lumbar spinal stenosis has become a common spinal disorder. Treatment modalities have been advancing, and the application of Enhanced Recovery After Surgery (ERAS) principles provides a new approach to postoperative recovery in patients. This study aims to investigate the clinical application effects of ERAS principles in single-level lumbar spinal stenosis surgery. Methods: This study included 64 patients who underwent lumbar fusion surgery in the Spinal Surgery Department of Baise People’s Hospital from July 2022 to July 2024. These patients were divided into an experimental group (ERAS group, 33 cases) and a control group (conventional group, 31 cases) based on perioperative care, receiving ERAS principles and traditional treatment, respectively. A comparison was made between the two groups in terms of gender, age, BMI, intraoperative blood loss, postoperative length of hospital stay, postoperative complications, hospital costs, VAS scores (preoperative/postoperative day 3), and ODI scores (preoperative/postoperative day 3). Results: There were no significant differences in gender, age, and BMI between the ERAS group and the conventional group (gender: χ2 = 0.5008, P = 0.4792;age: 54.55 ± 8.51 years vs. 57.39 ± 8.16 years, P = 0.0892;BMI: 25.11 ± 2.70 vs. 24.77 ± 2.75, P = 0.3098). However, during surgery, patients in the ERAS group had significantly less blood loss than those in the conventional group (197.58 ± 195.51ml vs. 438.71 ± 349.22 ml, P = 0.0006), and the postoperative length of hospital stay was significantly shorter (7.00 ± 2.24 days vs. 11.55 ± 5.23 days, P = 0.0000). On postoperative day 3, VAS scores were significantly better in the ERAS group compared to the conventional group (3.70 ± 0.88 vs. 4.32 ± 0.87, P = 0.0031), and the ODI scores showed significant improvement as well (46.00 ± 3.04 vs. 48.00 ± 3.39, P = 0.0078). Although there were no significant differences in postoperative complications and hospital costs (complications: 3 cases vs. 0 cases, P = 0.2154;hospital costs: 63524.29 ± 17891.80 RMB vs. 58733.84 ± 13280.82 RMB, P = 0.1154), ERAS demonstrated better postoperative recovery outcomes in single-level lumbar spinal stenosis surgery. Conclusion: The study results support the implementation of ERAS principles in single-level lumbar spinal stenosis surgery to promote rapid recovery, reduce healthcare resource consumption, and improve overall patient satisfaction.

CLINICAL OBSERVATION ON THE THERAPEUTIC EFFECT OF ACUPUNCTURE PLUS MANUAL REPOSITION FOR TREATMENT OF ACUTE LUMBAR VERTEBRAL ARTICULAR DYSKINESIA

Objective: To observe the therapeutic effect of acupuncture plus manual reposition for treatment of acute lumbar vertebral articular dyskinesia for choosing a better remedy. Methods: 66 cases of acute lumbar vertebral articular dyskinesia were randomly divided into acupuncture plus manual reposition group (treatment group, n=33) and routine manual reposition group (control group, n=33). Yaotong point was punctured, when, the patient was asked to move his or her waist simultaneously. Results: After one session of treatment, of the two 33 cases in treatment and control groups, 28 (84.85%) and 20 (60.61%) were cured, 4 (12.12%) and 9 (27.27%) were improved, and 1 (3.03%) and 4 (12.12%) failed in the treatment. The therapeutic effect of treatment group was significantly superior to that of control group (P<0.05). Conclusion: Acupuncture combined with manual reposition is apparently superior to simple routine manual reposition in relieving acute lumbar vertebral articular dyskinesia.

Influence of different operation methods on vertebral body parameters and GH-IGF axis of patients with thoracolumbar bursts fractures

Objective:To observe the influence situation of different operation methods on the vertebral body parameters and GH-IGF axis of patients with thoracolumbar bursts fractures.Methods:A total of 50 surgical patients with thoracolumbar bursts fractures from February 2014 to January 2016 were selected as the research object, and 50 patients with fractures were divided into two groups by the principle of random allocation, then the group A were treated with surgical treatment by anterior approach, the group B were treated with surgical treatment by posterior approach, then the vertebral body parameters and the serum expression levels of GH-IGF axis indexes of two groups before the surgery and at different time after the surgery were compared.Results: The vertebral body parameters and the serum expression levels of GH-IGF axis indexes of two groups before the surgery were compared (allP>0.05), while the vertebral body parameters and the serum expression levels of GH-IGF axis indexes of two groups at different time after the surgery were all significantly better than those before the surgery, and the results of group B were all better than those of group A (allP<0.05).Conclusions:The influence of surgical treatment by posterior approach for the vertebral body parameters and GH-IGF axis of patients with thoracolumbar bursts fractures are obviously better than those of surgical treatment by anterior approach, so the application value of surgical treatment by posterior approach in the patients with fractures is higher.

Efficacy and Safety of Low Molecular Weight Heparin Prophylaxis for Venous Thromboembolism Following Lumbar Decompression Surgery

Objective To evaluate the efficacy and safety of low molecular weight heparin (LMWH) prophylaxis for venous thromboembolism (VTE) after lumbar decompression surgery. Methods Patients at high or the highest risk of VTE who underwent lumbar spine surgery in Peking Union Medical College Hospital from January 2004 to April 2011 were included in the present study. All the patients received a half dose of LMWH 6 hours after surgery followed by a full dose LMWH once per day until discharge. We recorded incidences of deep venous thrombosis (DVT), pulmonary embolism (PE), bleeding complications, and medication side effects. Results Seventy-eight consecutive patients were eligible and enrolled in this study. The mean hospital stat was 8.5±4.5 days. No symptomatic DVT, PE, or major bleeding events were observed. One patient developed wound ecchymosis, another developed wound bleeding, four had mild hepatic aminotransferase level elevation, and one developed a suspicious allergic reaction. Conclusion LMWH may be applied as an effective and safe prophylaxis for VTE in high-risk patients undergoing lumbar decompression surgery.

Percutaneous Endoscopic Lumbar Spine Surgery for Lumbar Disc Herniation and Lumbar Spine Stenosis: Emphasizing on Clinical Outcomes of Transforaminal Technique

Lumbar Disc Herniation and Lumbar Spine Stenosis are the most common spine diseases which are mainly due to age related Spine degeneration. Diagnosis of both Lumbar Disc Herniation and Lumbar Spine Stenosis depends on clinical findings as well as radiological investigations. Treatment of choice of these conditions is on the basis of the patient conditions. Surgical treatment is the option only when the conservative treatment does not improve the patient’s clinical condition. Advancement and improvement of the technology have resulted in the traditional open surgical treatment into minimal invasive surgery. Intervention of the different surgical instruments with expert spinal surgeons had made percutaneous endoscopic lumbar Spine surgery as one of the preferred choices of surgery for treating Lumbar Disc Herniation and Lumbar Spine Stenosis. The concept of percutaneous endoscopic surgery for lumbar region is to provide surgical options without producing iatrogenic morbidity associated with the open surgical procedures. Conventionally, there are different approaches/techniques for Percutaneous Endoscopic Lumbar Spine Surgery, but in this review we are mainly focusing on the Transforaminal Technique. Regarding the Lumbar Disc Herniation treatment with transforaminal approach, a number of articles have been published due to which we mainly focused on those articles which were published after 2009 onwards. While fewer articles related to Lumbar Spine Stenosis treatment with Transforaminal approach were found, we tried to brief out all those articles. On the basis of comparative study of different surgeries done for Lumbar Disc Herniation and Lumbar Spine Stenosis, Percutaneous Transforaminal endoscopic Lumbar Surgery provides a substantial benefit. Transforaminal approach for treating Lumbar Disc Herniation and Lumbar Spine Stenosis is safe and effective. The Percutaneous Transforaminal Endoscopic Lumbar Surgery has advantage as it is performed under local anesthesia with shorter length of hospitalization and early return to normal life. The clinical outcome of the patient that underwent Percutaneous Transforaminal Endoscopic Lumbar Surgery for Lumbar Disc Herniation and Lumbar Spine Stenosis is quite good in regard of its fewer complication and more benefits.

Massively prolapsed intervertebral disc herniation with interlaminar endoscopic spine system Delta endoscope: A case series

BACKGROUND Surgery is often indicated for patients with massively prolapsed intervertebral disc herniation.The interlaminar endoscopic spine system(iLESSYS)Delta 6-mm working channel endoscope has advantages over other systems.The aim of this study was to explore the benefits and complications of using the iLESSYS Delta for the treatment of massively prolapsed intervertebral disc herniation.AIM To explore the clinical benefits of treating massively prolapsed lumbar intervertebral disc herniation with the iLESSYS Delta endoscope.METHODS In this study,the data of 37 patients who underwent surgery with the iLESSYS Delta endoscope at The Affiliated Hospital of Qingdao University were retrospectively analyzed.Intraoperative blood loss,operation time,and complications were collected.The visual analog scale(VAS),oswestry disability index(ODI),and modified MacNab criteria were determined before and at 1 d,3 mo,and 6 mo after surgery.RESULTS The mean intraoperative blood loss was 20.4±1.2 mL.The mean operation time was 97.3±12.4 min.The VAS scores for leg and back pain decreased from 68.0±7.3,34.4±8.5 before operation to 2.5±1.7,5.5±1.9 at 6 mo after surgery,respectively.The ODI also decreased from 60.2±7.3 to 17.9±3.4 at 6 mo after surgery.The improvement rate of the MacNab score was 86.4%,which was considered excellent.No spinal dural injury,nerve root injury,secondary protrusion of intervertebral disc,or myeloid hypertension was found during follow-up.CONCLUSION The iLESSYS Delta 6-mm working channel endoscope has several advantages in terms of clinical and functional benefits,complications,and low risk of residual vertebral pulp in treating patients with massively prolapsed intervertebral disc herniation.

Clinical Outcome of Percutaneous Endoscopic Lumbar Surgery (PELS) in Treatment of Lumbar Disc Herniation

Lumbar disc herniation is a spinal problem seen in both young and old people causing pain in the back with pain and numbness in lower extremity leading to disability limiting daily activities. When conservative treatments are ineffective, then it is treated by surgeries, more recently with minimal invasive percutaneous endoscopic lumbar surgery (PELS). One of the mostly accepted PELS by spinal surgeons is percutaneous transforaminal endoscopic lumbar discectomy, which can be performed for any age. The main aim of this review was to evaluate clinical outcome and safety based on the Oswestry Disable Index (ODI), Visual Analog Scale (VAS) and MacNab criteria and complications of PELS surgery and its advantages in clinical basis.

Perioperative outcomes in minimally invasive lumbar spine surgery: A systematic review

AIM: To compare minimally invasive(MIS) and open techniques for MIS lumbar laminectomy, direct lateral and transforaminal lumbar interbody fusion(TLIF) surgeries with respect to length of surgery, estimated blood loss(EBL), neurologic complications, perioperative transfusion, postoperative pain, postoperative narcotic use, and length of stay(LOS).METHODS: A systematic review of previously published studies accessible through Pub Med was performed. Only articles in English journals or published with English language translations were included. Level of evidence of the selected articles was assessed. Statistical data was calculated with analysis of variance with P < 0.05 considered statistically significant.RESULTS: A total of 11 pertinent laminectomy studies, 20 direct lateral studies, and 27 TLIF studies were found. For laminectomy, MIS techniques resulted in a significantly longer length of surgery(177.5 min vs 129.0 min, P = 0.04), shorter LOS(4.3 d vs 5.3 d, P = 0.01) and less perioperative pain(visual analog scale: 16 ± 17 vs 34 ± 31, P = 0.04). There is evidence of decreased narcotic use for MIS patients(postoperative intravenous morphine use: 9.3 mg vs 42.8 mg), however this difference is of unknown significance. Direct lateral approaches have insufficient comparative data to establish relative perioperative outcomes. MIS TLIF had superior EBL(352 mL vs 580 mL, P < 0.0001) and LOS(7.7 d vs 10.4 d, P < 0.0001) and limited data to suggest lower perioperative pain.CONCLUSION: Based on perioperative outcomes data, MIS approach is superior to open approach for TLIF. For laminectomy, MIS and open approaches can be chosen based on surgeon preference. For lateral approaches, there is insufficient evidence to find noninferior perioperative outcomes at this time.

Erector spinae plane block at lower thoracic level for analgesia in lumbar spine surgery: A randomized controlled trial

BACKGROUND Patients undergoing lumbar spine surgery usually suffer severe pain in the postoperative period.The erector spinae plane block(ESPB),first published in 2016,can anesthetize the ventral and dorsal rami of thoracic nerves and produce an extensive multi-dermatomal sensory block.AIM To assess whether bilateral ultrasound-guided ESPB at a lower thoracic level could improve pain control and quality of recovery in patients undergoing lumbar spine surgery.METHODS A total of 60 patients aged 18-80 years scheduled to undergo lumbar spine surgery with general anesthesia were randomly assigned to two groups:ESPB group(preoperative bilateral ultrasound-guided ESPB at T10 vertebral level)and control group(no preoperative ESPB).Both groups received standard general anesthesia.The main indicator was the duration to the first patient controlled intravenous analgesia(PCIA)bolus.RESULTS In the ESPB group,the duration to the first PCIA bolus was significantly longer than that in the control group(h)[8.0(4.5,17.0)vs 1.0(0.5,6),P<0.01],and resting and coughing numerical rating scale(NRS)scores at 48 h post operation were significantly lower than those in the control group(P<0.05).There was no significant difference between the two groups regarding resting and coughing NRS scores at 24 h post operation.Sufentanil consumption during the operation was significantly lower in the ESPB group than in the control group(P<0.01),while there was no significant difference between the two groups regarding morphine consumption at 24 or 48 h post operation.In the ESPB group,Modified Observer’s Assessment of Alertness/Sedation score within 20 min after extubation was higher and duration in the post-anesthesia care unit was shorter than those in the control group(P<0.01).CONCLUSION In patients undergoing lumbar spine surgery,ultrasound-guided ESPB at a lower thoracic level improves the analgesic effect,reduces opioid consumption,and improves postoperative recovery.

Minimally Invasive Open Reduction and Internal Fixation for Osteoporotic Vertebral Compression Fractures: Technical Report and Mid-Term Outcomes

Background: Traditional open instrumentation may cause surgical complications due to fragile bones and induce medical comorbidities in senile patients. Vertebroplasty and kyphoplasty are palliative augmentation procedures that have been associated with increased risks of cement leakage, adjacent fractures and non-union. Objective: The aim of this study was to describe a novel approach for the union of osteoporotic vertebral compression fractures with minimally invasive open reduction and internal fixation. Patients and Methods: Seven consecutive patients with intractable back pain without neurological deficits due to osteoporotic vertebral compression fractures were treated using minimally invasive fixation with intra-vertebral expandable pillars and artificial bone substitute. The clinical symptoms and image findings were recorded. Results: All of the patients reported relief of back pain, and the height of the vertebral bodies was well restored. X-ray findings obtained 2 to 4 years after the procedures showed fracture healing and favorable formation of the callus confirmed in the anterior longitudinal ligament. Conclusion: This mini-open procedure with intravertebral devices is an effective and reliable technique for osteoporotic vertebral compression fractures and may avoid complications related to traditional open spinal instrumentation procedures and augmentation with bone cement.

Transient Symptomatic Bilateral Optic Disc Oedema Following Lumbar Spinal Surgery— An Unusual Presentation

Background: Optic disc oedema has various underlying pathologies, however, unless visually disabling does not usually bring a patient to the physician. The more common symptoms of headache, nausea and vomiting lead to the incidental detection of bilateral disc oedema [1]. Optic disc oedema seen following spinal surgery is usually associated with visual acuity changes and often goes by the acronym POVL (Peri/ postoperative visual loss) wherein, as the name goes, visual acuity changes are profound [2] [3] [4]. Purpose: We would like to highlight a case of transient Bilateral Optic Disc oedema following Lumbar spinal surgery maintaining normal visual acuity and attaining spontaneous resolution. Case Report: A 42-year-old female presented with transient obscuration of vision and flashes of light post an uneventful lumbar spinal surgery. Ophthalmic evaluation revealed normal visual acuity and pupils but marked disc edema right more significant than left. There was no colour vision deficit, neither any field changes. By a process of exclusion, it was likely the patient had developed bilateral disc oedema secondary to the spinal surgery. On follow-up 6 weeks and 3 months later, the oedema had completely settled and visual acuity remained at 6/6. Conclusion: Optic disc oedema can be unilateral or bilateral with some of the uncommon conditions mentioned secondary to spinal surgery, however, in those situations, visual loss has been severe and permanent. Our case is unusual in its combination of disc edema with normal acuity along with its transient nature and resolution and to our knowledge, has not been published before.

Techniques of Surgery for Lumbar Spinal Stenosis: A Comparative Study

Aim: To compare between classic open surgeries and minimally invasive surgeries in Lumbar Spinal Stenosis. Methods: A comparative descriptive study, involved 117 patients suffering from lumbar canal stenosis, aged between 40 - 70 years;admitted to department of Neurosurgery from March 2011 till august 2016 in King Fahad Hospital in Saudi Arabia. Study groups are consisted of group A as patients managed with classical laminectomy, group B as patients managed with endoscopic spinal procedures and group C as patients managed with microscopic decompression facilitated by the Metrex Tubular System. SPSS was used in data entry and analysis, and ethical considerations taken into consideration and participants filled the required inform consents. Results: Age of particaoncet ranged from 45 - 63 years, Mean +/&#8210;50. The degenerative canal stenosis with acute disc single level (cauda equina syndrome) was the most common type of lumbar canal stenosis encountered in group A;the unilateral foraminal and lateral recess stenosis without disc prolapse was the most common type of lumbar canal stenosis encountered in group B;while the unilateral foraminal and lateral recess stenosis without disc prolapse was the most common type of lumbar canal stenosis encountered in group C. Classic laminectomy and disectomy used mostly in group A;endoscopic unilateral decompression lamino-foraminotomy without discectomy used mostly in group B and bilateral microscopic laminectomy without discectomy followed by unilateral microscopic laminoforaminotomy without discectomy used mostly in group C. Mean of operation duration was the highest in both gender of group A, followed by group B, then group C. Unintended durotomy was the most common intra operative complications occurred in the whole study especially in group A. Mean of blood lost was the highest in both gender of group A, followed by group B, then group C. Postop complications in the patients of study groups were the highest in group A (33.3%), followed by group B (8.5%) and then group C (2%). Conclusion: Microscopic decompression facilitated by the Metrex Tubular System is the most effective technique of Surgery for Lumbar Spinal Stenosis and the least intra-operative and post-operative complications.

Safety control strategy for vertebral lamina milling task

Vertebral lamina milling task is one of the high-risk operations in spinal surgeries. The operation is to remove part of vertebral lamina and release the pressure on the spinal nerve. Because many important vessels and nerves are under the vertebral lamina, any incorrect operation may cause irreparable damage to patients. To improve the safety of lamina milling task, a fuzzy force control strategy is proposed in this paper. Primary experiments have been conducted on bone samples from different animals. The results show that, with the fuzzy force control strategy, the bone milling system can recognize all surgery states and halt the tool at the proper location, achieving satisfactory surgery performance.

A rare case report:tubercular spondylodiscitis following lumbar disc surgery

Postoperative spondylodiscitis is a rare but serious complication after lumbar disc surgery.Most cases are due to more virulent organisms such as Staphylococcus aureus and Streptococcus.No case of post operative tubercular spondylodiscitis has been reported till date to our knowledge. We are reporting a case of tubercular spondylodiscitis followed by lumbar disc surgery of L2-3 level.

Evaluation of current surgeon practice for patients undergoing lumbar spinal fusion surgery in the United Kingdom

AIM: To ascertain current surgeon practice in the United Kingdom National Health Service for the management of patients undergoing lumbar spinal fusion surgery. METHODS: Descriptive survey methodology utilised an online questionnaire administered through SurveyMonkey. Eligible participants were all surgeons currently carrying out lumbar spinal fusion surgery in the National Health Service. Two previous surveys and a recent systematic review informed questions. Statistical analyses included responder characteristics and pre-planned descriptive analyses. Open question data were interpreted using thematic analysis.RESULTS: The response rate was 73.8%. Most surgeons(84%) were orthopaedic surgeons. Range of surgeon experience(1-15 years), number of operations performed in the previous 12 mo(4-250), and range of information used to predict outcome was broad. There was some consistency of practice: most patients were seen preoperatively; all surgeons ensured patients are mobile within 3 d of surgery; and there was agreement for the value of post-operative physiotherapy. However, there was considerable variability of practice: variability of protocols, duration of hospital stay, use of discharge criteria, frequency and timing of outpatient follow up, use of written patient information and outcome measures. Much variability was explained through patient-centred care, for example, 62% surgeons tailored functional advice to individual patients. CONCLUSION: Current United Kingdom surgeon practice for lumbar spinal fusion is described. The surgical procedure and patient population is diverse, and it is therefore understandable that management varies. It is evident that care should be patient-centred. However with high costs and documented patient dissatisfactionit is important that further research evaluates optimal management.

56 CASES OF DISTURBANCE IN SMALL ARTICULATIONS OF THE LUMBAR VERTEBRAE TREATED BY PUNCTURING THE EFFECTIVE POINTS -A New System of Acupuncture

In this series,he patients with disturb-ance of small articulations of the lumbarvertebrae were treated by puncturing the ef-fective points and reduction by manual trac-tion with satisfactory results,the cure ratebeing 39.3％,the markedly effective rate28.6％,with a total effective rate 98.3％.This method is simple and easy to master,and highly effective.Therefore it is very ac-ceptable to the patients.It is a very excellenttherapeutic method for disturbance of smallarticulations of the lumbar vertebrae,some-times complicated by acute lumbar sprainand chronic lumbar strain.

Application of Particle Filter for Vertebral body Extraction: A Simulation Study

Lumbar vertebra motion analysis provides objective measurement of lumbar disorder. The automatic tracking algorithm has been applied to Digitalized Video Fluoroscopy (DVF) sequence. This paper proposes a new Auto-Tracking System (ATS) with a guide device and a motion analysis to automatically measure human lumbar motion. Digitalized Video Fluoroscopy (DVF) sequence was obtained during flexion-extension lumbar movement under guide device. An extraction of human vertebral body and its motion tracking were developed by particle filter. The results showed a good repeatability, reliability and robustness. In model test, the maximum fiducial error is 3.7% and the repeatability error is 1.2% in translation and the maximal repeatability error is 2.6% in rotation angle. In this simulation study, we employed a lumbar model to simulate the motion of lumber flexion- extension with the stepping translation of 1.3 mm and rotation angle of 1&deg;. Results showed that the fiducial error was measured as 1.0%, while the repeatability error was 0.7%. The sequence can be detected even noise contamination as more as 0.5 of the density. The result demonstrates that the data from the auto-tracking algorithm shows a strong correlation with the actual measurement and that the Vertebral Auto-Tracking System (VATS) is highly repetitive. In the human lumbar spine evaluation, the study not only shows the reliability of Auto-Tracking Analysis System (ATAS), but also reveals that it is robust and variable in vivo. The VATS is evaluated by the model, the simulated sequence and the human subject. It could be concluded that the developed system could provide a reliable and robust system to detect spinal motion in future medical application.