Recurrent Disc Research Articles

Endoscopic lumbar discectomy vs microdiscectomy: Early results, complications and learning curve an Australian perspective

BackgroundEndoscopic spine surgery has been recently introduced in Australia. A comparison of endoscopic lumbar discectomy, open or microscopic approach with learning curve is presented. Patients and methodsA retrospective observational cohort study design of Uniportal endoscopic lumbar discectomy of a single surgeon series was conducted. All patients above 18 years of age with symptomatic disc herniation and who have failed non-surgical management were selected. This data is the initial 30 consecutive uniportal endoscopic lumbar discectomy patients (group E). These were compared to the immediately prior 30 lumbar microdiscectomy (Group M) cases of the same surgeon. Demography, operative data, complications and postoperative results were collected. Learning curve duration for endoscopic cases was also examined. ResultsThere were 39 males and 21 females with mean age of 53.6 yrs. In group E there were 23 Transforaminal cases and 7 interlaminar cases. Mean operative time was 125.5 min. The first 10 cases took 181 mins, next 111mins and last 10, 84 mins showing a vast improvement with learning curve. A significant difference in operative time between transforaminal endoscopic and interlaminar endoscopic discectomy (P < 0.001) was found. On comparison of endoscopic and microscopic cases a significant difference was found in blood loss (p < 0.001) and there was an expected non-significant difference in operation time. Complication rates at 6 weeks were comparable (dural tears – 1 E, 2 M) and recurrent discs (E = 1,M = 2). An additional recurrence occurred at 20 weeks postop in the endoscopic group that required a revision discectomy surgery. ConclusionWe present an Australian perspective of endoscopic vs microscopic lumbar discectomy. Early results reveal comparable outcomes of endoscopic lumbar discectomy compared to microscopic surgery with respect to operative time, blood loss and complications. In endoscopic cases, interlaminar approach had longer operative time and complications compared to transforaminal approach. With the learning curve the operative times improved. Further studies are required to evaluate long term outcomes and complications.

Overweight and smoking promote recurrent lumbar disk herniation after discectomy

PurposeRecurrent lumbar disk herniation (rLDH) following lumbar microdiscectomy is common. While several risk factors for primary LDH have been described, risk factors for rLDH have only sparsely been investigated. We evaluate the effect of Body mass index (BMI) and smoking on the incidence and timing of rLDH.MethodsFrom a prospective registry, we identified all patients undergoing primary tubular microdiscectomy (tMD), with complete BMI and smoking data, and a minimum 12-month follow-up. We defined rLDH as reherniation at the same level and side requiring surgery. Overweight was defined as BMI > 25, and obesity as BMI > 30. Intergroup comparisons and age- and gender-adjusted multivariable regression were carried out. We conducted a survival analysis to assess the influence of BMI and smoking on time to reoperation.ResultsOf 3012 patients, 166 (5.5%) underwent re-microdiscectomy for rLDH. Smokers were reoperated more frequently (6.4% vs. 4.0%, p = 0.007). Similarly, rLDH was more frequent in obese (7.5%) and overweight (5.9%) than in normal-weight patients (3.3%, p = 0.017). Overweight smokers had the highest rLDH rate (7.6%). This effect of smoking (Odds ratio: 1.63, 96% CI: 1.12–2.36, p = 0.010) and BMI (Odds ratio: 1.09, 95% CI: 1.02–1.17, p = 0.010) persisted after controlling for age and gender. Survival analysis demonstrated that rLDH did not occur earlier in overweight patients and/or smokers.ConclusionsBMI and smoking may directly contribute to a higher risk of rLDH, but do not accelerate rLDH development. Smoking cessation and weight loss in overweight or obese patients ought to be recommended with discectomy to reduce the risk for rLDH.

Short Term Clinical Outcome of Micro Lumbar Discectomy in Tertiary Care Center

Background: Minimal invasive open lumbar microdiscectomy has been associated with good success rate and low morbidity. The present study is aimed to evaluate the clinical outcome of patients who underwent open minimal invasive open lumbar microdiscectomy for herniated intervertebral disc.&#x0D; Materials and Methods: This is a prospective observational hospital based study of prolapsed lumbar intervertebral disc operated in the department of neurosurgery at Nobel Medical College Teaching Hospital, Biratnagar, Nepal from January 2018 to June 2021. All patients of lumbar herniated intervertebral disc subjected for surgery were included. Recurrent prolapsed intervertebral disc, Disc surgery requiring stabilization was excluded from the study. During surgery types of prolapsed intervertebral disc, level and operative time were noted. In the post-operative period Visual Analogue Scale was used to assess the change in severity of pain. Duration of hospital stay and the complications occurred were also noted.&#x0D; Results: The mean age of the study population was was 41.50 (±14.56) years ranging from 20 years to 79 years. The commonest lumbar prolapsed intervertebral disc was at L4-L5 level. The mean operative time was 42 minutes excluding the time for anaesthesia preparation. There was statistically significant difference (p&lt;0.001) in pre-operative and post-operative Visual Analogue Scale. Mean duration of hospital stay was 5.58 (1.87) days.&#x0D; Conclusion: A through workup and surgical planning is associated with better outcome avoiding complications in minimal invasive open micro lumbar discectomy.

Long-term outcomes of the repeated lumbar microdiscectomies using polyacrylamide hydrogel: clinico-radiological relevance

Background. Epidural fibrosis (EF) is one of the reasons of the failed back surgery syndrome manifesting in back pain and pain in extremities as well as other signs of the compression or irritation of the nerve structures. The numerous approaches to prevent EF have been elaborated. Nowadays, many years of experience in the usage of different barrier materials in microdiscectomy such as polyacrylamide hydrogel (PAH) have been accumulated. Nevertheless, the results of such treatment are rather controversial. The aim of the study was to assess the radiological data on the state of the backbone according to MRI findings and the clinical symptoms of the patients following the surgery as well as to determine the long-term strength of the interaction between the factors under study after the repeated lumbar microdiscectomies performed with intraoperative epidural PAH administration. Materials and methods. The results of the clinical and radiological assessment of 96 patients (mean age 45.7 years; 95 % CI [43.5; 47.9]; 59 males and 37 females) enrolled into the single-center prospective cohort study performed at the State Institution «Romodanov Neurosurgery Institute National Academy of Medical Sciences of Ukraine» have been presented. The patients were divided into two groups. The main group (MG) consisted of 35 (36.5 %) patients with recurrent intervertebtral disc (IVD) herniation to whom PAH was administered epidurally at the final step of the surgery comprising disc removal and decompression of the nervous structures with the aim of preventing cicatrical adhesive EF. In control group (61 patients, 63.5 %), barrier materials were not used. The primary end-points of the study were the long-term outcomes of the repeated lumbar microdiscectomies: EF rate at the postoperative site; the rate of the displacement of spinal root at the postoperative site; the rate of the repeated recurrent IVD herniation and de novo IVD herniation; the rate of the cases with the residual radicular pain localized in the area of the surgical intervention and the extent of the worsening of life quality in the treated patients. The secondary end-points of the study were the following: the analysis of the associations with delineation of the strength of such factorsaffecting the residual radicular pain as EF, the displacement of spinal root at the postoperative site, the repeated recurrent IVD herniation the repeated recurrent IVD herniation and de novo IVD herniation. Results. In 12 months following the surgical treatment, EF frequency was significantly lower in MG as compared with CG where PAH was not used (p = 0.02936). Nevertheless, the difference between groups was not significant when MRI findings of the displacement of spinal root at the postoperative site (р = 0.46759), the frequency of the repeated recurrent IVD herniation (p = 0.90904) and de novo IVD herniation (p = 0.60385) were compared. In study group, there were no association between MRI signs of postoperative EF, the displacement of spinal root or new recurrent IVD herniation on the one hand and the frequency of the radicular pain localized at the area of the surgical intervention on the other hand (p = 0.66482; p = 0.09515; p = 0.22857, respectively). In CG, the significant association between the displacement of spinal root at the postoperative site and the clinical symptoms above was revealed (p = 0.00222) with association coefficient φ = 0.41 indicating the moderate strength of this association. Conclusions. The data obtained generally suggest the reasonability of applying PAH manufactured in Ukraine as a barrier material at least for the treatment of the patients with recurrent IVD herniation representing the challenging category of spinal patients.

Foraminoplasty at the Base of the Superior Articular Process with Bone Drilling for Far-Downward Discs in Percutaneous Endoscopic Lumbar Discectomy: A Retrospective Study.

PurposePercutaneous endoscopic lumbar discectomy (PELD) is usually used to treat lumbar disc herniation (LDH). This study aims to describe PELD by foraminoplasty in the treatment of far-downward migrated LDH and to demonstrate the clinical efficacy by a retrospective evaluation.Patients and MethodsBetween January 2017 and July 2018, 41 patients with far-downward migrated LDH were treated with PELD by foraminoplasty at the base of the superior articular process (SAP). Clinical efficacy was evaluated with a visual analogue scale (VAS) score, the Oswestry disability index (ODI), and the modified Macnab criteria. Postoperative follow-up data (1 month, 6 months, 18 months) were recorded.ResultsThe surgical levels included L2/3 (1 patient), L3/4 (1 patient), L4/5 (17 patients), and L5/S1 (22 patients). The VAS and ODI scores indicated a significant improvement 18 months after surgery (mean ± standard deviation, VAS, 6.9±1.3 versus 0.5±0.8; ODI, 66.3±12.2 versus 14.0±8.2, respectively). Based on the modified Macnab criteria, 92.7% of patients had a good-to-excellent rate. There were three patients with a dural tear, and one patient had recurrent disc herniation.ConclusionPELD by foraminoplasty at the base of the superior articular process is a good method for treating far-downward migrated LDH.

Characteristics and Short-Term Surgical Outcomes of Patients with Recurrent Lumbar Disc Herniation after Percutaneous Laser Disc Decompression.

Background and Objectives: Although percutaneous laser disc decompression (PLDD) is one of the common treatment methods for patients with lumbar disc herniation (LDH), the recurrence of LDH after PLDD is estimated at 4–5%. This study compares the preoperative clinical data and clinical outcomes of patients who underwent primary microendoscopic discectomy (MED) or MED following PLDD. Materials and Methods: We retrospectively analyzed 2678 patients who underwent MED for LDH. The PLDD group included patients with previous PLDD history at the same level of LDH, and a matched control group was created using propensity score matching for age, sex, and body mass index. Preoperative data, preoperative radiographic findings, and surgical data of the groups were compared. To compare postoperative changes in clinical scores between the groups, a mixed-effect model was used. Results: As a result, 42 patients (1.6%) had previously undergone PLDD, and a control group with 42 patients were created. The disc degeneration severity was not significantly different between the groups. However, Modic changes were more frequent in the PLDD group than in the matched control group (p = 0.028). There were no significant differences in dural adhesion rate or surgery-related complications including dural injury, length of stay, and recurrence rate of LDH after surgery. In addition, the improvement of clinical scores did not significantly differ between the two groups (p = 0.112, 0.913, respectively). Conclusions: We concluded that patients with recurrent LDH after PLDD have advanced endplate degeneration, which may reflect endplate injury from a previous PLDD. However, a previous history of PLDD does not have a negative impact on the clinical result of MED.

843 Annular Closure Device for Disc Herniation: Meta-Analysis of Clinical Outcome and Complications

Abstract Aim To assist surgeons to determine a potential approach to reduce incidences of recurrent lumbar disc herniation and assess the current devices regarding their outcomes and complications. Method Four electronic full-text databases were systematically searched through September 2017. All results were pooled utilising meta-analysis with weighted mean difference and odds ratio as summary statistics. Results Four studies met inclusion criteria. Three studies reported the use of Barricaid (ACD) while one study reported the use of Anulex (AR). A total of 24 symptomatic reherniation were reported among 811 discectomies with ACD/AR as compared to 51 out of 645 in the control group (OR: 0.34; 95% CI: 0.20,0.56; I2 = 0%; P &amp;lt; 0.0001). Durotomies were lower among the ACD/AR patients with only 3 reported cases compared to 7 in the control group (OR: 0.54; 95% CI: 0.13, 2.23; I2 = 11%; P = 0.39). Similar outcomes for post-operative Oswestry Disability Index and visual analogue scale were obtained when both groups were compared. Conclusions Early results showed the use of Barricaid and Anulex devices are beneficial for short term outcomes demonstrating a reduction in symptomatic disc reherniation with low post-operative complication rates. Long-term studies are required to further investigate the efficacy of such devices.

Intraoperative anti-inflammatory drugs combined with no drainage after MIS-TLIF in the treatment of recurrent lumbar disc herniation: an RCT

BackgroundMinimally invasive-transforaminal lumbar interbody fusions (MIS-TLIF), in which the nerve root pain is caused by early postoperative edema reaction, is a common clinical complication. However, there is no effective method to solve this problem. We aimed to use gelatin sponge impregnated with mixed anti-inflammatory drugs combined with no drainage after MIS-TLIF to optimize postoperative effect in the treatment of recurrent lumbar disc herniation (LDH).MethodsFrom June 2018, the middle-aged patients (45–60 years old) with recurrent LDH were recruited. Included patients were treated with MIS-TLIF surgery, and no drainage tube was placed after surgery. All patients were randomly divided into intervention group (gelatin sponge impregnated with mixed anti-inflammatory drugs) and control group (saline was immersed in gelatin sponge as a control).ResultsThe intervention group included 63 cases, and the control group included 65 cases. The length of hospital stays and bedridden period in the intervention group were significantly lower than those in the control group (P < 0.05). The VAS score of low back pain in the intervention group was significantly lower than that of the control group at postoperative days 1–6 (P < 0.05, for all). The VAS scores of leg pain in the intervention group at postoperative days 1–9 were statistically lower than the control group (P < 0.05, for all).ConclusionsApplication of gelatin sponge impregnated with mixed anti-inflammatory drugs combined with no drainage after MIS-TLIF can significantly further optimize the surgical effect of recurrent LDH and shorten the bedridden period and hospital stays, to achieve the purpose of early rehabilitation.Trial registrationChina Clinical Trial Registration Center, ChiCTR1800016236. Registered on May 21, 2018, http://www.chictr.org.cn/listbycreater.aspx

Overweight and smoking are associated with reoperation for recurrent lumbar disc herniation

Overweight and smoking are associated with reoperation for recurrent lumbar disc herniation

Should Annular Closure Devices Be Utilized to Reduce the Risk of Recurrent Lumbar Disk Herniation?

Should Annular Closure Devices Be Utilized to Reduce the Risk of Recurrent Lumbar Disk Herniation?

Functional outcome of Destandau technique of endoscopic discectomy for symptomatic lumbar disc herniation

Functional outcome of Destandau technique of endoscopic discectomy for symptomatic lumbar disc herniation - IJOS- Print ISSN No: - 2395-1354 Online ISSN No:- 2395-1362 Article DOI No:- 10.18231/j.ijos.2020.044, Indian Journal of Orthopaedics Surgery-Indian J Orthop Surg

McKenzie-type Exercises Improve the Functional Abilities of a Patient with Recurrent Herniated Discs: A Case Report

This case is unique in which the patient had two previous lumbar spinal surgeries, recurrent herniated discs, and new bulged and herniated discs were developed. We aimed to investigate whether implementing the McKenzie method would reduce the symptoms of a long history of Low Back Pain (LBP) with multiple surgeries. A 2-months of McKenzie-type exercise program was performed at a rate of 5 days/week. Disability index, pain intensity, lumbar Range of Motion (ROM), and lower limb strength were tested before and after the exercise treatment intervention. Disability and pain were also measured at 3-months follow-up. The Oswestry disability index and pain visual analogue scale score reduced immediately after the treatment intervention and remained reduced at 3-months follow-up from 44% to 22%, and from 8 to 4, respectively. Lumbar ROM improved about 1.5 cm during standing flexion and 3 cm during extension. Unilateral leg extension of the affected leg and bilateral leg press increased by 16.5 kg and 70 kg, respectively. The current protocol has shown that Mckenzie-type exercise treatment can improve the physical functions and reduce pain in a patient with a history of lumbar spine surgeries and prolonged LBP. In addition, despite no additional exercise, McKenzie method increased the lower limb strength, possibly through nerve root decompression.

Canadian Spine SocietyPresentation CPSS1: Spinal insufficiency fracture in the geriatric pediatric spinePresentation CPSS2: The clinical significance of tether breakages in anterior vertebral body growth modulation: a 2-year postoperative analysisPresentation CPSS3: Anterior vertebral body growth modulation for idiopathic scoliosis: early, mid-term and late complicationsPresentation CPSS4: Ovine model of congenital chest wall and spine deformity with alterations of respiratory mechanics: follow-up from

Canadian Spine SocietyPresentation CPSS1: Spinal insufficiency fracture in the geriatric pediatric spinePresentation CPSS2: The clinical significance of tether breakages in anterior vertebral body growth modulation: a 2-year postoperative analysisPresentation CPSS3: Anterior vertebral body growth modulation for idiopathic scoliosis: early, mid-term and late complicationsPresentation CPSS4: Ovine model of congenital chest wall and spine deformity with alterations of respiratory mechanics: follow-up from

Is fusion the most suitable treatment option for recurrent lumbar disc herniation? A systematic review

ABSTRACT Objective Recurrent lumbar disc herniation (rLDH) is a common issue after primary discectomy and can cause severe pain, morbidity, and reoperation. The purpose of this systematic review was to evaluate the surgical management of recurrent lumbar disc herniation. Methods A systematic literature search was conducted using Pubmed and Embase databases on 18thAugust, 2019. The inclusion and exclusion criteria were applied according to study design, surgical approach, language, number of patients; and spinal level. Data extracted included patient demographics, and clinical outcomes (patients with excellent/good outcomes; VAS back and leg score improvement, complication and recurrence rates). Results Sixteen studies, (comprising of seven prospective and nine retrospective) met the inclusion criteria. Ten studies evaluated discectomy only; four analysed fusion, and two analysed both discectomy only and fusion approaches. Fusion approaches recorded a superior success rate (8.3 % higher, p>0.05); postoperative VAS back score improvement (5 % higher, p>0.05) than discectomy alone. However, discectomy alone approaches recorded a more favourable postoperative VAS leg score improvement (4.2 % higher p>0.05), and complication rate (3.2% lower, p>0.05) than fusion techniques. Conclusion There is significant heterogeneity in clinical outcomes reported for studies after surgical intervention in rLDH patients. Neither discectomy nor fusion’s superiority was statistically significant. Despite fusion yielding longer operative times, and length of stay (adding to the expense), it is superior in minimising mechanical instability and recurrence. Finally, we conclude that both approaches are equally efficacious in rLDH cases, and choice should be based on a case by case basis.

Clinical outcomes of spinal endoscopic surgery for tiny lumbar disc herniation with severe radiating pain of lower limb

To study the clinical characteristics of the patients with tiny lumbar disc herniation and severe symptoms(tLDHSS) and the therapeutic effects of percutaneous endoscopic lumbar discectomy(PELD). From January 2014 to February 2019, 34 patients with tLDHSS were reviewed retrospectively, including 20 males and 14 females, aged from 31 to 73 (48.8±10.1) years, with a follow up duration ranged from 8 to 48 (21.8±10.3) months. The clinical manifestations, imaging and surgical data were analyzed. The visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores were analyzed before operation, 1 month after operation and at the latest follow-up. The preoperative and postoperativescores were compared. At the latest follow up, the Macnab system was used to evaluate the effects of the operation. The main symptom of 34 cases was severe radiation pain on one side of lower limbs. The duration of preoperative symptoms ranged from 0.33 to 84 months. The disc herniation was found in 7 cases of L4, 5 and 27 cases of L5S1. According to the MSU division of lumbar disc herniation, 31 cases were located in area B. In all cases, it was confirmed that the protruding nucleus compressed the nerve root, and in 26 cases, the nerve root was obviously inflamed. The operation time ranged from 30 to 80 min, with a mean time of (43.5±9.5) min. The preoperative VAS score was 8.1±1.3 and ODI score was 31.8±6.7. And the VAS score was 1.1± 0.3, 0.7±0.4 on the first month after operation and the latest follow up, respectively. The ODI score was 5.3±2.1 and 0 to 10 (with a median score of 2) on the first month after operation and the latest follow-up respectively. The postoperative VAS and ODI scores were improved compared with preoperative scores.At the latest follow up, 28 cases got an excellent result and 6 cases good according to Macnab evaluation system. During the follow-up period, only one patient had recurrent disc herniation. The main symptom of patients with tLDHSS is severe radiation pain on one side of lower limb. It manifests as sudden onset and shorter course of disease. Severe local inflammation was induced by local compression of the protruding nucleus pulposus on the nerve root out of the dura. For this kind of patients, thin layer CT scan has an important diagnostic value. In the treatment of this kind of patients, the symptoms are relieved rapidly, the curative effect is definite and the recurrence rate is low.

Management of recurrent unilateral lumbar disc herniation in a single level: unilateral versus bilateral pedicle screws fixation with interbody fusion

BackgroundLumbar interbody fusion procedure is a recognized surgical technique in management of a variety of lumbar pathologies including recurrent lumbar disc prolapse. Interbody fusion augmented by pedicle screw fixation has been considered to improve fusion rates and clinical outcomes. Interbody fusion is commonly associated with better fusion potentials through applying the bone graft in the load bearing, vascular position of the anterior, and middle spinal columns. However, it still remains unknown whether interbody fusion with unilateral pedicle screw fixation (UPSF) is superior to that with bilateral pedicle screw fixation (BPSF).Aim of the workThe aim of this study is to evaluate the efficacy and safety of unilateral versus bilateral pedicle screw fixation associated with interbody fusion for the management of single level unilateral recurrent lumbar disc prolapse as regard the clinical and biomechanical results, operation time, intraoperative blood loss, and postoperative stay.Material and methodsThis observational prospective comparative study of the two groups who were operated either unilateral (group A /15 patients) or bilateral (group B/15 patients) pedicle screw fixation with interbody fusion was done. Patients were followed up for 1, 6, ad 12 months.ResultsSignificant improvement in functional outcome of the two groups was noted compared to preoperatively, except in early postoperative period where the back VAS and ODI in the unilateral group was better than bilateral group. However, on further follow up, no significant difference was noticed. There was no significant difference comparing fusion rate, complication rate, and duration of hospital stay between the two groups at postoperative follow-up. There was significantly less blood loss, and significantly shorter operation time in the unilateral PS fixation group as compared with the bilateral PS fixation group in our study.ConclusionOur study suggested that TLIF with unilateral PS fixation was as safe and effective as that with bilateral PS fixation for the management of recurrent single level lumbar disc prolapse; it showed better clinical outcome scores of ODI and back VAS, and a significant reduction of the intraoperative blood loss as well as the operation time, without significant differences considering fusion rate, complication rate, and duration of hospital stay between the two groups at postoperative follow-up. However, BPSF with TLIF likely causes more degeneration at the cranial adjacent segment compared with UPSF techniques. Nevertheless, the long-term follow up is required to demonstrate the impact of these findings.

P139. Clinically relevant percent reduction (CRPR): a new definition of clinically significant change for lumbar spine surgery

BACKGROUND CONTEXT Minimal clinically important difference (MCID) represents the smallest, clinically relevant change in a patient-reported outcome (PRO) score. However, the literature suggests that an absolute change from baseline may not be a reliable marker of response to treatment for patients with a low or high baseline PRO score. An alternative to MCID is a threshold of clinical relevance defined by percent reduction from baseline PRO score. PURPOSE The purpose of this study was to determine whether a clinically relevant percent reduction (CRPR) of 30% in disability and pain scores is a valid method for determining clinical improvement at 12 months after lumbar spine surgery. STUDY DESIGN/SETTING Retrospective evaluation of prospectively collected data from a national surgical spine registry, the Quality Outcomes Database (QOD). PATIENT SAMPLE A total of 23,280 participants undergoing elective surgery for a lumbar degenerative condition (primary stenosis, disc herniation, spondylolisthesis (Grade I) and symptomatic mechanical disc collapse or revision surgery for recurrent same-level disc herniation, pseudarthrosis and adjacent segment disease). OUTCOME MEASURES Outcomes were disability (ODI), back and leg pain (NRS-BP/LP), and satisfaction (NASS scale). METHODS Participants completed a preoperative assessment and follow-up assessment at 1-year. The change in ODI and NRS-BP/LP scores were categorized as met CRPR (percent change ≥30%) or not met CRPR (percent change RESULTS Results from the satisfaction prediction models found that the OR for 30% ODI CRPR was 11.1 (10.2 to 12.1) and for ODI MCID was 7.8 (7.2 to 8.4), while 30% NRS-BP and NRS-LP CRPR was 7.9 (7.3 to 8.5) and 6.7 (6.2 to 7.2) compared to MCID ORs of 5.5 (5.1 to 5.9) and 5.6 (5.2 to 6.0) (p CONCLUSIONS CRPR may be a more clinically relevant method for identifying response to treatment since it can be applied to broad spinal surgery populations and takes into account the baseline PRO score. Furthermore, a 30% CRPR appears to outperform established MCID thresholds for patients with either low or high preoperative disability and pain scores. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

185. Reoperation rates after single-level lumbar discectomy in the military health system

BACKGROUND CONTEXT Despite advances in surgical techniques, rates of recurrent lumbar disc herniation (LDH) range from 5-24%, representing the most common cause of surgical failure and subsequent reoperation. PURPOSE Our goal was to determine the reoperation rate, time to reoperation and type of revision procedures performed after single-level discectomy for LDH within the military health system. STUDY DESIGN/SETTING Restrospective. PATIENT SAMPLE Military health system. METHODS Using CPT codes to capture lumbar microdiscectomy procedures, 3,999 patients undergoing primary single-level microdiscectomy for lumbar disc herniation were identified between October 2012 and November 2017. Demographic data, as well as number and type of revision surgical intervention were investigated. Rates of subsequent procedures involving instrumented fusion and complications were recorded. RESULTS We identified 415 patients (10.3%) who required a revision surgery for a same-level reherniation. Of these patients requiring revision surgery at the same level of the index procedure, 9.3% required more than one revision surgery. The majority of first-time revision procedures consisted of revision microdiscectomy (290/415, 69.9%); however, 125 patients (30.1%) underwent single- or multi-level fusion for definitive treatment at time of first revision. Of the 40 patients requiring more than one revision, 21 (52.5%) eventually required a fusion procedure, which was significantly higher than patients having only one revision (p= CONCLUSIONS In our retrospective study of 3,999 patients undergoing single-level microdiscectomy for lumbar disc herniation, we identified 415 patients (10.4%) undergoing subsequent reoperation for a recurrent LDH at the same level. Within this group, 9.6% would require two or more reoperations, and 52.5% of these patients would ultimately undergo a lumbar arthrodesis at the same level as the initial disc herniation. Our findings characterize the lumbar disc reherniation population in the military, with major implications for the prognosis and treatment strategy of these commonly-treated injuries. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Examination of metal mobilization from a gunshot by scanning acoustic microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and inductively coupled plasma optical emission spectroscopy: a case report

BackgroundProjectile foreign bodies are known to cause chronic heavy metal toxicity due to the release of metal into the bloodstream. However, the local effect around the metallic object has not been investigated and the main goal of our study is to examine the influence of the object in close proximity of the object.Case presentationA 36-year-old Caucasian woman with one metallic pellet close to her sciatic nerve due to a previous shotgun injury at the gluteal area presented with a diagnosis of recurrent lumbar disk herniation at L4–5 level. A physical examination confirmed chronic neuropathy and she underwent a two-stage surgery. The surgery included removal of the foreign body, followed by discectomy and fusion at the involved level. During the removal of the metallic foreign body, a tissue sample around the pellet and another tissue sample from a remote area were obtained. The samples were analyzed by scanning acoustic microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Lead, chromium, copper, cadmium, iron, manganese, selenium, and zinc elements in tissue, blood, and serum specimens were detected by inductively coupled plasma optical emission spectroscopy.ConclusionsAn acoustic impedance map of the tissue closer to the metallic body showed higher values indicating further accumulation of elements. Energy-dispersive X-ray spectroscopy results confirmed scanning acoustic microscopy results by measuring a higher concentration of elements closer to the metallic body. Scanning electron microscopy images showed that original structure was not disturbed far away; however, deformation of the structure existed in the tissue closer to the foreign body. Element analysis showed that element levels within blood and serum were more or less within acceptable ranges; on the other hand, element levels within the tissues showed pronounced differences indicating primarily lead intoxication in the proximity of the metallic body. We can state that residues of metallic foreign bodies of gunshot injuries cause chronic metal infiltration to the surrounding tissue and induce significant damage to nearby neural elements; this is supported by the results of scanning acoustic microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and inductively coupled plasma optical emission spectroscopy.

Short-term effects of combined pedicle/facet screw fixation plus interbody fusion through the channel-assisted muscle-splitting approach for the treatment of degenerative lumbar spine diseases in the elderly

Objective To examine the feasibility and early effects of unilateral pedicle screw fixation in combination with contralateral translaminar facet screw fixation plus interbody fusion through the channel-assisted muscle-splitting approach for the treatment of degenerative lumbar spine diseases in elderly patients. Methods A total of 82 elderly patients with degenerative lumbar spine diseases received treatment between January 2015 and June 2016.Of these patients, 25 had lumbar spinal stenosis, 42 had degenerative lumbar instability, 13 had giant lumbar disc herniation, and two had recurrent lumbar disc herniation; There were 69 cases of single segment and 13 cases of double segment lesions.Perioperative evaluation, imaging evaluation, and clinical evaluation were performed, and surgical complications were analyzed. Results The average length of incision was (2.6±0.4) cm in cases of single segment lesions and (4.4±0.5) cm in cases of two segment lesions.The mean operation time was (98.3±19.6) minutes and peri-operation blood loss was (232.2±25.8) ml.The post-operation height of the intervertebral disc space significantly increased at the last follow-up(P<0.05); the height of the intervertebral disc space was restored and well maintained with internal fixation showing no loosening, breakage or Cage shift.The post-operation lumbar coronal Cobb angle decreased(P<0.05)while the sagittal Cobb angle increased(P<0.05)at the last follow-up.There was no significant difference in the area and grade of the multifidus muscle on MRI 12 months after operation.Seventy-two patients were followed up for 12-18 months(mean=16.8 months), and there were 67 cases of intervertebral fusion(93.1%). The last follow-up showed a Japanese Orthopaedic Association(JOA)score of (25.8±1.7), which was significantly higher than the pre-operation score(10.6±1.3), with an excellence rate of 88.9%.The Oswestry Disability Index score was significantly reduced, from (50.9±21.6) at pre-operation to (9.6±4.8) at the last follow-up.There were 78 patients with primary wound healing, three cases of superficial wound necrosis, one case of dural tear, and one case of nerve root injury.No cardiovascular or cerebrovascular incident was observed during or after operation. Conclusions Combined pedicle/facet screw fixation plus interbody fusion through the channel-assisted muscle-splitting approach shows satisfactory short-term effects when used for the treatment of degenerative lumbar spine diseases in the elderly and possesses advantages such as minimal invasiveness, limited bleeding, quick recovery, high fusion rates and significantly improved clinical outcomes.However, further clinical studies are required to assess its medium-and long-term efficacy. Key words: Spinal fusion; Surgical procedures minimally invasive; Arthritis, degenerative