Intraoperative Dural Tear Research Articles

Influence of incidental dural tears and their primary microendoscopic repairs on surgical outcomes in patients undergoing microendoscopic lumbar surgery

BACKGROUND CONTEXTDural tear represents a common complication of microendoscopic spine surgery that may lead to postoperative sequelae including insufficient decompression, cerebrospinal fluid fistula, intracranial hypotension, and subdural/intraparenchymal bleeding. The gold standard to manage intraoperative dural tears is primary repair. However, the downside of conversion to open surgery can be detrimental. Therefore, understanding the most appropriate strategy for microendoscopic dural repair and its impact on postoperative outcomes is of importance. PURPOSEThe purpose of this study was to investigate the incidence of dural tears in patients undergoing microendoscopic lumbar surgery and to elucidate their influence on surgical outcomes whenever proper repair is accomplished microendoscopically without conversion to open surgery. STUDY DESIGN/SETTINGA retrospective multicenter cohort study of prospectively enrolled patients using a propensity-matched analysis. PATIENT SAMPLEA total of 922 consecutive patients underwent microendoscopic surgery of the lumbar spine between February and December 2012 in the three institutions belonging to our study group. OUTCOME MEASURESOutcome measures included the Numeric Rating Scale for back and leg pain, Oswestry Disability Index, Japanese Orthopaedic Association score, Short Form-36, and a patients’ satisfaction scale. METHODSAll incidental dural tears were repaired by microendoscopic suture of the dura mater from inside to outside using double-arm needles and/or by fibrin glue coverage without being converted to open surgery. Surgical outcomes were compared between patients with and without dural tears using a propensity-matched analysis. RESULTSMicroendoscopic discectomy for lumbar disc herniation was performed on 474 patients, whereas microendoscopic laminectomy and posterior lumbar interbody fusion for lumbar canal stenosis were performed on 271 and 177 patients, respectively. Dural tears occurred in 49 (5.3%) patients. Of these, 23 (2.5%) patients required suture repair, whereas the rest received a fibrin patch for a pinhole tear, all of which were successfully performed under microendoscopy. Six hundred (65.1%) patients responded pre- and postoperatively to the questionnaire. Of them, the responses of 38 patients with dural tears were compared with those of 38 matched patients. No significant differences in any outcome measures were observed between the two groups. CONCLUSIONSIn conclusion, all dural tears in our cases were managed without conversion to open surgery and did not influence surgical outcomes.

Post-Operative Spinal Epidural Hematoma after Thoracic and Lumbar Spinous Process-Splitting Laminectomy for Thoracic and Lumbar Spinal Stenosis.

Introduction To investigate the risk of epidural hematoma after spinous process-splitting laminectomy (SPSL). Methods A total of 137 cases (mean age, 72.4 years; 68 men) of SPSL were included. Of these, there were instances (3.7%; mean age, 70.5 years; all male) of postoperative development of new neurologic deficit due to epidural hematoma requiring reoperation. The 133 subjects (72.5 years; 64 men) with normal postoperative course were used as controls, and comparisons were made between both groups using chi-squared and Student's t-tests. Regarding our investigation of risk factors for epidural hematoma, logistic regression was conducted with presence or absence of hematoma as our primary outcome variable, and age, gender, disease duration, number of laminectomies, which levels were decompressed, blood loss, length of case, drain output, coagulopathy, and whether or not there was an intraoperative dural tear were our explanatory variables. Results All cases of hematoma were single-level laminectomies; there was one case of T9-10 and 3 cases of L2-3. In our direct comparison of both groups (hematoma versus control), the proportion of men was significantly higher in the hematoma group (100% versus 48%, p < 0.05); levels decompressed were also significantly higher (p < 0.05) in the hematoma group, and drain outputs were significantly lower (113 mL versus 234 mL, p < 0.05). From our logistic regression analysis, the levels were significantly higher (χ2 = 15, p = 0.0001) and the drain outputs were smaller (χ2 = 4.6, p = 0.03) in the hematoma group. Conclusions Single-level decompression higher than the L2-3 level and reduced drain output were risk factors for spinal epidural hematoma. With this method of spinous process suturing and reconstruction there is less decompression compared with more conventional methods; therefore, the effect of hematoma may be more pronounced at higher vertebral levels with reduced canal width, and drain failure may also occur with this limited space.

Orbital Expansion in Cranial Vault After Minimally Invasive Extradural Transorbital Decompression for Thyroid Orbitopathy

To test the hypothesis that the orbit expands in the cranial vault after wide dural exposure after minimally invasive extradural transorbital decompression for thyroid eye disease. A cross-sectional cohort study of 36 patients (60 orbits). Preoperative and postoperative (6 months) orbital CT following extradural transorbital decompression was analyzed. Primary outcome measure was the percentage area of the cranial vault occupied by orbital and brain tissue in a predefined window before and after surgery. Secondary outcome measures were displacement of the anteriormost aspect of the temporal lobe, reduction in clinical proptosis, change in clinical activity score, and change in diplopia. The mean percentage of the selected area of the cranial vault preoperatively was 0% orbital and 44% ± 15% brain tissue, compared with 70% ± 16% orbital and 28% ± 14% brain tissue postoperatively (p < 0.001). Posterior movement of the brain was demonstrated in 59 of 60 orbits, with a mean displacement of 2.0 mm ± 1.3 mm (p < 0.001). Mean proptosis reduction was 11.2 mm ± 3.6 mm (p < 0.001). The proportion of patients with clinical activity score <3 compared with clinical activity score ≥3 was not significantly different after surgery (p = 0.163). Improved diplopia was noted in 5 patients (14%), and worsening diplopia was noted in 3 patients (8%), although these changes were not significant (p = 0.772). Intraoperative dural tear with cerebrospinal fluid leak was reported in 2 orbits (3%), which was successfully managed with fibrin glue, with no sequelae. No other complications were noted, including infection, spontaneous orbital pulsations, postoperative hemorrhage (intracranial or intraorbital), or reactivation of disease. With wide exposure of the middle cranial fossa dura following extradural transorbital decompression, orbital tissue typically expands in the cranial vault.

Endoscopic Approach Technique for Recurrent Lumbar Prolapsed Disc

Introduction: Recurrent disc after lumbar discectomy is not uncommon, with most of the patients requiring a new surgery. A greater bone decompression and scar tissue dissection become necessary with the new procedure, resulting in a higher chance of postoperative complications. Recently, many surgeons have begun to treat recurrent disc with endoscopic approaches, in order to reach the prolapsed disc avoiding tissue dissection. We present our up-to-dated experience on the treatment of recurrent disc by endoscopic technique. Material and methods: We prospectively collected 30 patients treated for recurrent lumbar disc prolapse, from May 2016 to December 2017, with an endoscopic procedure. We collected data on age, sex, location, diagnosis, leg pain by VAS, and degree of disability via the Oswestry Disability Index (ODI), and if any adverse events occurred. All patients underwent an ODI (Oswestry Disability Index) and a VAS (Visual Analogue Scale) questionnaire before the operation and after 3, 6 and 15 months [3-6] at the follow-up visit. No patients were lost at follow-up. Patients characteristics: Age at presentation ranged between 23 and 78 years with a male to female ratio of 1.5 to 1. The level treated more was L4-L5. In all cases, we performed transforaminal route access, except for two, where an interlaminar approach was necessary because of the disc fragment location. Twenty-six cases had been operated previously by microsurgical access and the remaining by an endoscopic technique. In one case the disc had recurred for a second time, requiring open revision surgery. Results: Median operative time was 52 minutes (range 44 to 79 minutes). After a median follow up of 15 months (range 15-24 months) 93% of patients were pain-free. Pain by VAS ranged from a mean value of 6.3 at admission to 1.9 at 15 months of follow-up. ODI scores went from a mean preoperative value of 59.8% to 14.6% at the same follow-up. Four patients experienced transient paresthesia along the dermatomeric distribution of the involved nerve, while 3 had an intraoperative dural tear. One patient had to undergo new revision surgery for a disc recurrence. No late adverse events occurred. Conclusions: Endoscopic discectomy might be a valuable procedure for recurrent lumbar disk prolapse treatment. Our results showed good outcomes with only a few transient complications and less postoperative pain. Also, iatrogenic mechanical instability might be avoided with this technique.

Foramen magnum syndrome after iatrogenic cerebrospinal fluid leak during lumbar spine surgery: A series of two cases

Foramen magnum syndrome (FMS) is a rare complication from lumbar spine surgery. Cerebrospinal fluid (CSF) leaks can be difficult to treat. FMS is a dangerous complication due to excessive distal CSF drainage from a dural tear or secondary to a “controlled” lumbar drainage. We present two cases of FMS after iatrogenic CSF leaks. Both patients underwent decompressive laminectomy as a part of the index surgery. Intraoperative dural tear was not identified in either case. A postoperative computed tomography (CT) myelogram ordered in view of the positional headaches indicated a CSF leak. A lumbar drain was placed, but both the patients worsened symptomatically. CT head in Case 1 indicated tonsillar ectopia within the foramen magnum, while that in Case 2 revealed a posterior fossa hemorrhage with fullness of the foramen magnum and profound hydrocephalus. Both patients were treated surgically. Additional corrective measures were also initiated to reverse the pathology. Both patients made a good recovery with resolution of symptoms. Development of neurological changes in a patient with CSF leak may indicate an acute intracranial process. Treatment of foramen magnum syndrome requires prompt realization of the underlying pathology and measures to cease or modulate the CSF drainage. The dangers of excessive distal CSF drainage, whether it is from a dural tear or from “controlled” lumbar drainage, should be considered.

Thoracic myelopathy secondary to ossified ligamentum flavum and dural ossification – A series of 19 cases and review of literature

Objective: Thoracic myelopathy has gradually risen to be a prominent diagnosis in patients with persistent upper back pain, bladder symptoms and spastic paraparesis. Often encountered, these conditions pose a serious dilemma to neurosurgeons with respect to surgical planning, timing of surgery, prognosis and possible complications and outcome assessment. In view of these queries and to clarify the indications of when to intervene the following study has been undertaken. To analyze the clinical presentation, radiological features, clinical implications and surgical nuances and outcomes in patients with single and multiple level dorsal canal ossified ligamentum flavum (D-OLF) and associated dural ossification (DO). Patients and methods: Nineteen patients with the diagnosis of thoracic myelopathy (TM) were identified between January 2012 and March 2017. All patients were treated surgically, with decompressive laminectomies, in a single tertiary care center in Southern India. mJOA was calculated preoperatively and assessed postoperatively and a mean mJOA was calculated to assess the significance in neurological improvement. The data was collected from the medical records department and various factors were analyzed, using SPSS software, for correlation.Results: Mean age of our group was 50.84 years with a range of 29 to 71 years. It comprised of 11 males and 8 females. All patients had features of myelopathy. Surgery did have a positive effect on neurological improvement (p = 0.001) in all patients except one. Dural ossification had correlation with pre op and post op urinary disturbances with p value of 0.02. (Mann Whitney Test for 2 independent variables used). A total of ten patients had urinary symptoms pre operatively, out of which six patients showed postoperative improvement at the end of one year. Four of these patients continued to have symptoms, two patients were on Clean Intermittent Catheterisation (CIC), and one patient had features of hesitancy and frequency. Preoperative bladder dysfunction was a strong predictor for continued bladder dysfunction at the end of 1 year (p < 0.004). Conclusions: All patients with D-OLF and or DO presented with myelopathic features. MRI with concurrent CT spine helps to delineate dural ossification from D-OLF and helped to rule out other differentials. The classical “tram track” and “comma sign” is well noted in CT spine and helps to plan surgical approach and anticipate probable complications. Patients with concurrent D-OLF and DO and long segment pathology had increased risk of intraoperative dural tears and postoperative CSF leaks. These subset of patients had a peaked incidence of bladder involvement or non-improvement of existing bladder dysfunction, postoperatively. Patients with D-OLF and DO seemed to do better after surgical decompression. Surgery should be offered once diagnosis is confirmed on imaging, as all patients in out study, except one, showed postoperative neurological improvement.Our study concluded that patients with prolonged preoperative symptoms persisted to have them even after surgery. Patients with concurrent D-OLF and DO showed more significant improvement, postoperatively, in terms of mJOA – postop with a p = 0.002 as compared to patients with D-OLF alone.We recommend that each case be treated individually and treatment should be planned appropriately, based on the radiology and levels involved, keeping in mind the preoperative symptoms and their duration.

Role of closed drain after multi-level posterior spinal surgery in adults: a randomised open-label superiority trial.

To explore the role of closed suction drain in multi-level posterior spinal surgery. We performed prospective, open-label, randomised control, superiority trial with parallel design and 1:1 allocation. A total of 161 patients undergoing posterior spinal surgery involving more than one motion segment at a dedicated spine surgery department were randomly allocated into "drain" or "no-drain" groups, based on which surgical drain was employed at the end of surgery. After excluding six cases with intraoperative dural tear, the data of 80 patients in "drain" and 75 patients in "no-drain" group were analysed. Primary outcome was total perioperative blood loss (sum of intraoperative blood loss, volume of drain if present and volume aspirated if patient developed collection in relation to surgical wound). The secondary outcomes were transfusion requirements, wound healing and complications. Both groups were comparable with respect to baseline characteristics. Total perioperative blood loss was significantly higher in "drain" group (716 ± 312.97ml vs 377.9 ± 295.72ml, p < 0.0001). Number and volume of post-operative aspirations were significantly higher in "no-drain" group whereas transfusion requirements were significantly higher in "drain" group. Except for one case of superficial wound inflammation in either group, there were no complications. Subgroup analysis revealed that the results were applicable for surgeries involving "two/three" levels and "more than three" levels. The practice of not using closed surgical drains after multi-level posterior spinal surgery reduces post-operative blood loss and transfusion requirements. But this comes with the disadvantage of increased wound soakage and need for post-operative wound aspirations. The risks of benefits of "drain" and "no drain" must be carefully weighed and an informed choice be taken. These slides can be retrieved under Electronic Supplementary Material.

Posterior Vertebral Column Resection in Management of Severe Post-traumatic Thoracolumbar Kyphosis

ground Data: Thoracolumbar fractures nowadays are considered the commonest spinal fractures and its treatment remains one of the major controversies. Post-traumatic kyphosis (PTK) is considered the commonest serious complication of poorly managed thoracolumbar fractures which can affect the patient health quality of life. Different corrective osteotomy techniques are described to correct this deformity but with limited correction in sever angular kyphotic deformity. Our hypothesis was, among several osteotomies described to correct kyphosis, vertebral column resection (VCR) provides the highest angle of correction required to manage patients with severe PTK.Purpose: To evaluate the safety and efficacy of posterior VCR in the treatment of patients with severe degrees of post-traumatic thoracolumbar kyphosis and determine the degree of correction in sagittal imbalance and its relationship with functional outcome of the patients.Study Design: This prospective clinical case study.Patients and Methods: Twelve patients suffering from PTK and managed with posterior VCR were recruited for this study. The mean local kyphosis angle (LKA) was 64.1±6.3ᴼ. Outcome measures were Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) and radiological using local kyphosis angle (LKA), global kyphosis (GK), lumbar lordosis (LL) and sagittal vertical axis (SVA). The mean follow up time was 13.5±2 months.Results: The mean LKA and SVA score improved from 64.1± 6.3o and 52.6±8.3mm preoperatively to 8.8±3.4o and 13.1±4.8mm postoperatively, respectively. All were statistically significant. Functionally, the VAS score of back pain significantly reduced from 6.8±0.9 to 1.7±0.8 and the Oswestry Disability Index significantly improved from 59.8±7.5 to 11.6±3.4. No major complications were reported apart from intraoperative dural tear in 2 patients, superficial infection in one patient, deep infection in one patient and temporary paraparesis in one patient.Conclusion: Posterior VCR can provide satisfactory correction in severe PTK and improvement in functional outcome with appropriate application and fine surgical technique. (2018ESJ165)

Medical Malpractice Claims Following Incidental Durotomy Due to Spinal Surgery.

Retrospective cohort study. Analyze medical malpractice verdicts and settlements associated with incidental durotomy. Incidental durotomy is a common complication of spine surgery. Although most intraoperative dural tears are repaired without sequelae, persistent Cerebrospinal Fluid leak, infection, or neurological injury can yield adverse outcomes. The medicolegal implications of incidental durotomy are poorly understood. Three separate, large legal databases were queried for cases involving incidental durotomy. Case, plaintiff, procedure, and outcome characteristics were analyzed. In total, 48 dural tear-related medical malpractice cases were analyzed. Most cases (56.3%) resulted in a ruling in favor of the defendant physician. Most cases alleged neurological deficits (86.7%). A large majority of cases without neurological sequelae had an outcome in favor of the defendant (83.3%). For cases involving a payment, the average amount was $2,757,298 in 2016 adjusted dollars. Additional surgery was required in 56.3% of cases, a delay in diagnosis/treatment of durotomy was present in 43.8%, and alleged improper durotomy repair was present in 22.9%. A favorable outcome for the plaintiff was more likely in cases with versus without alleged delay in diagnosis/treatment (61.9% vs. 29.6%, P = 0.025) and improper durotomy repair technique (72.7% vs. 35.1%, P = 0.040). Repeat surgery was not associated with favorable outcome for the plaintiff (42.8% cases with reoperation vs. 38.1% without, P = 0.486). This analysis of durotomy-associated closed malpractice claims after spine surgery is the largest yet conducted. Durotomy cannot always be considered an entirely benign event, and these findings have several direct implications for clinicians: late-presenting or dehiscent durotomy may be associated with adverse outcomes and subsequent risk of litigation, timely reoperation in the event of durotomy-related complications may not increase surgeon liability, and spine surgeons should be prepared to defend their choice of durotomy repair technique, should dehiscence occur. 3.

Efficacy of Endoscopic Surgery in Management of Patients with Lumbar Canal Stenosis

Background Data: The treatment of lumbar stenosis has originally included extensive resections of posterior neural arch components. Moreover, wide muscular dissection and retraction is generally used to accomplish sufficient visualization. With the advancing noninvasive neuro-imaging modalities; the major component of neurological pressure typically occurs at the level of the interlaminar window. Microendoscopic decompressive laminotomies (MEDL) have now increased popularity among spine specialists for the treatment of lumbar canal stenosis. It has been developed from the unilateral hemilaminotomy technique.Purpose: To evaluate the efficacy of lumbar endoscopic decompression in patients of segmental lumbar canal stenosis from a unilateral skin incision.Study Design: A prospective clinical case study.Patients and Methods: A total of 30 patients 10 males and 20 females were operated in Alexandria Main University Hospital, during the period from January 2013 to June 2015. The degree of pain and disability were assessed pre-operatively using the Visual Analogue Scale (VAS), both for radicular pain and back pain (if present), and the Oswestry Disability Index (ODI). The length of the incision, the duration of surgery, the operative blood loss, and duration of hospital stay were calculated. Mean follow up period for patients was 38.5±18.2 months (Range, 36-48).Results: The mean age was 62.7±6.9 years. All patients had claudicating sciatica; 57% had bilateral sciatica, while 43 % had unilateral sciatica. 60% had low back pain. Only 3 patients (10%) had motor weakness preoperatively. 24 patients (80%) had single level affection, while 6 patients (20%) had double level affection. We operated totally on 36 segmental levels. There was a statistically significant reduction for the mean values of VAS both for radicular pain and back pain in the follow up period (P<0.001). Also, there was a statistically significant reduction for the ODI mean value in the follow up period (P<0.001). Operative blood loss was 109.5±63.2 ML. Mean operative time was 103.8±32.7 minutes. Mean duration of hospital stay was 1.5±0.6 days (Range, 1-3 days). We had two patients of intraoperative dural tears (7%) with no postoperative CSF leak occurred, two patients (7%) had superficial wound infection, no patients had deep wound infection or discitis, and no patients encountered of postoperative instability in the follow up period. Conclusion: Endoscopic surgery for bilateral decompression through a unilateral approach is a useful and effective procedure for treating patients with lumbar canal stenosis with encouraging results. (2018ESJ161)

P.013 Convulsive status epilepticus due to intracranial hypotension

Background: Intracranial hypotension (IH) is typically characterized by an orthostatic headache. There have been limited case reports describing iatrogenic IH presenting with seizures. Methods: Case report. Results: A 71-year-old woman with chronic back pain developed convulsive status epilepticus (SE), characterized by generalized clonic seizures, immediately following scoliosis surgery. She had no history of seizures or seizure risk factors. Despite treatment with Midazolam, Phenytoin and Lacosamide, seizures recurred five times over three hours. Thus, Propofol and Midazolam infusions were initiated. An electroencephalogram revealed burst suppression and bilateral hemispheric epileptiform discharges. MRI brain was consistent with IH without cortical vein thrombosis. Fluid from the surgical drains was positive for Beta-2 transferrin, indicating cerebral spinal fluid. Her intracranial hypotension was likely due to an -intraoperative dural tear causing SE. Over two weeks, she remained on bedrest, sedation was weaned, and Phenytoin and Lacosamide were tapered and discontinued. She had no further seizures. Conclusions: IH is an under recognized cause of seizure following spinal or cranial surgery, lumbar puncture, or spinal anaesthesia. Proposed mechanisms include traction on cortical structures, increased cerebral blood flow and cortical irritation secondary to subdural hygromas.

Evaluation of the Results of Unilateral Pedicular Fixation and Interbody Fusion in Treatment of Degenerative Lumbar Disc Disease

Background data: Chronic discogenic back pain caused by degenerative disc disease is a common problem in general population. In clinical practice, lateral recess stenosis and foraminal stenosis may induce nerve root compression which can cause unilateral symptoms. Less invasive spinal fusion is performed by a unilateral approach, which maysignificantly minimize or diminish the iatrogenic soft tissue injury, the intra-operative blood loss, the postoperative pain and the duration of hospital stays. Purpose: to evaluate the efficacy of PLIF and unilateral pedicle screw fixation indegenerative lumbar disc disease Study Design: A prospective clinical case study.Patient and Methods: This study was carried out on 30 patients (16 males and 14 females) with mean age of 40.35±9.82 years. All failed conservative treatment and had confirmed diagnosis radiologically. All underwent posterior lumbar decompression, interbody fusion with single oblique cage filled with local bone and unilateral pedicle screw fixation. Clinical assessment was done using Visual Analogue Scale (VAS) and ODI. Radiological assessment of fusion was done using BSF criteria. Patients were followed for 17.77±7.17 months postoperatively.Results: According to ODI; 12 patients (40%) had excellent clinical results, 15 (50%) had good results, 3 (10%) had fair results. The mean VAS of leg pain improved from 6.80±1.37 to 2.17±0.91, where the VAS of back pain improved from 5.33±1.18 to 2.13±0.90 postoperative. All sensory and motor deficits cleared apart from 3 patients with mild leg paresthesia. Radiologically, 28 patients (93%) showed successful fusion at the end of the follow up period. Reported complications include, one (3.3%) wound infection, one (3.3) intra-operative dural tear, and two partial (grade 3) foot drop. There were two patients with pseudoarthrosis, although there was no case of implant failure or screw breakage.Conclusion: Our data suggest that conducting PLIF using the diagonal insertion of a single cage with supplemental unilateral transpedicular screw instrumentation enables sufficient decompression and solid interbody fusion. (2017ESJ152)

S2 Alar Iliac Fixation in Long Segment Constructs, a Two- to Five-Year Follow-up

Study DesignRetrospective review of patients having undergone S2 alar-iliac (S2AI) fixation for long fusions with a minimum two-year follow-up. ObjectivesTo report on fusion rates, complications, technique-specific complications of patients having undergone S2AI fixation. Summary of background dataSacropelvic fixation continues to be a challenge when performing long fusions to the pelvis. S2AI screws have been found to provide solid biomechanical fixation and have been found to have good clinical results in short-term follow-up for pediatric and adult patients. MethodsCases were retrospectively reviewed in patients who had placement of S2AI screws for long fusions with at least a two-year follow-up. Demographic data, complications, and reoperations were reviewed. Complications were broken into minor and major categories similar to previous series on pelvic fixation. ResultsThere were 86 cases identified. Minor and major complications occurred in 29% and 24% of patients, respectively, with the majority of minor complications being intraoperative dural tears. Revision surgery for all causes was performed in 23% of the cohort. Fusion rate at L5–S1 for patients without preoperative pseudarthrosis was 95.3%. Preoperative L5–S1 pseudoarthrosis was identified in 20 patients, 17 (95%) of these went onto fusion after one surgery. There was evidence of S2AI screw lucency in 10.4% of cases. However, the majority of these were asymptomatic. ConclusionsSacropelvic fixation using the S2AI technique provides safe, durable fixation with low rates of technique-specific complications and limited need for hardware removal. Complication rates in this series were similar to other series on long fusions to the pelvis. Additionally, fusion rates were high at L5–S1 for both patients with and without preoperative L5–S1 pseudarthrosis. It appears that the S2AI technique is a powerful option for patients with previous L5–S1 pseudarthrosis. Level of EvidenceLevel III.

Clinical outcome and surgical strategies for late post-traumatic kyphosis after failed thoracolumbar fracture operation: Case report and literature review.

Rationale:Thoracic-lumbar vertebral fracture is very common in clinic, and late post-traumatic kyphosis is the main cause closely related to the patients’ life quality, which has evocated extensive concern for the surgical treatment of the disease. This study aimed to analyze the clinical outcomes and surgical strategies for late post-traumatic kyphosis after failed thoracolumbar fracture operation.Patient concerns:All patients presented back pain with kyphotic apex vertebrae between T12 and L3. According to Frankel classification grading system, among them, 3 patients were classified as grade D, with the ability to live independently.Diagnoses:A systematic review of 12 case series of post-traumatic kyphosis after failed thoracolumbar fracture operation was involved.Interventions:Wedge osteotomy was performed as indicated—posterior closing osteotomy correction in 5 patients and anterior open-posterior close correction in 7 patients.Postoperatively, thoracolumbar x-rays were obtained to evaluate the correction of kyphotic deformity, visual analog scales (VAS) and Frankel grading system were used for access the clinical outcomes.Outcomes:All the patients were followed up, with the average period of 38.5 months (range 24–56 months). The Kyphotic Cobb angle was improved from preoperative (28.65 ± 11.41) to postoperative (1.14 ± 2.79), with the correction rate of 96.02%. There was 1 case of intraoperative dural tear, without complications such as death, neurological injury, and wound infection. According to Frankel grading system, no patient suffered deteriorated neurological symptoms after surgery, and 2 patients (2/3) experienced significant relief after surgery. The main VAS score of back pain was improved from preoperative (4.41 ± 1.08) to postoperative (1.5 ± 0.91) at final follow-up, with an improvement rate of 65.89%.Lessons:Surgical treatment of late post-traumatic kyphosis after failed thoracolumbar fracture operation can obtain good radiologic and clinical outcomes by kyphosis correction, decompression, and posterior stability.

Incidental Durotomy in Open Versus Tubular Revision Microdiscectomy: A Retrospective Controlled Study on Incidence, Management, and Outcome.

Retrospective case-control study. To compare the incidence, management, and outcome of incidental durotomy in revision microdiscectomy with open and minimal-access surgery. Incidental durotomy occurs with a variable incidence of 3%-27% in spine surgery. The highest rate occurs in revision microdiscectomy. The intraoperative and postoperative management of dural tears varies in the literature and the definite impact on clinical outcome has to be clarified. This is a retrospective study of medical records of 135 patients who underwent revision microdiscectomy, divided into 2 subgroups: OPEN (n=82) versus minimal-access surgery (MINI, n=53). Occurrence of intraoperative dural tears, intraoperative and postoperative management of durotomy, and clinical outcomes, according to MacNab criteria, were retrospectively examined. Statistical comparisons for categorical values between groups were accomplished using the 2-tailed Fisher exact test. P-values <0.05 were considered to be statistically significant. The incidence of durotomy in group OPEN was 19.5% (n=16/82) and in group MINI 17.0% (n=9/53) (P=0.822). The majority of durotomies (23/25) were repaired with an absorbable fibrin sealant patch alone. Postoperative cerebrospinal fluid fistula occurred only in 1 case of the OPEN group and was treated with lumbar drainage without the need for a reoperation. Patients with durotomy of the MINI group tended to have better outcome compared with those of the OPEN group without being statistically significant. The incidence of durotomy and postoperative cerebrospinal fluid fistula in lumbar revision microdiscectomy does not significantly differ between minimal-access and standard open procedures. The application of a fibrin sealant patch alone is an effective strategy for dural repair in revision lumbar microdiscectomy.

Dural ectasia associated with Mounier-Kuhn syndrome: a novel association in the context of spinal stenosis

We present the case of a patient undergoing lumbar spine decompression for stenosis with a history of Mounier-Kuhn syndrome. The patient presented with axial lumbar spine pain over 6 months...

Full endoscopic treatment of dural tears in lumbar spine surgery.

An incidental durotomy is a common complication of spinal surgery. Its treatment remains challenging, especially in endoscopic procedures. The objective of this study is to describe a technique for endoscopic dural closure which is safe and effective. From a prospective database all endoscopic spinal procedures with incidental durotomy were identified. Retrospectively, video recordings were analysed with a special reference to the applied technique of dural closure. Additionally 1, 6 and 12week follow-up examinations were evaluated for clinical outcome and associated complications. Out of 212 consecutive patients, an intraoperative dural tear was observed in nine patients (4.2%). A dural tear occurred in 1.1% of cases of lumbar disc herniation, in 7.9% of cases with lumbar spinal stenosis, in 37.5% of cases with a synovial cyst. An autologous muscle sample was harvested within the operative field and grafted at the dural defect in several layers. Fixation of the transplantation and watertight closure were achieved by the application of fibrin sealant with gelfoam. The mean time for dural closure was 209s (range 47-420s). Postoperatively no CSF fistula, no new deficits nor worsening of a pre-existing neurological deficit occurred. None of the patients had problems with wound healing, or discomfort which could be related to the CSF leak. Dural closure with an autologous muscle graft in combination with fibrin sealant patch is a fast, safe and alternative technique for the management of dural tear in microendoscopic surgery.

Predictive factors for neurological deterioration after surgical decompression for thoracic ossified yellow ligament.

To investigate the rate and predictive factors of post-operative neurological deterioration in ossified yellow ligament (OYL) surgery. A retrospective review was conducted for all patients with thoracic OYL causing myelopathy requiring surgical decompression from January 1998 to December 2012. Clinical parameters under study included clinical presentation, distribution of OYL, pre-operative walking score, pre- and post-operative neurological status, status of intra-operative neurophysiological monitoring, and modified Japanese Orthopaedic Association (mJOA) score. Any complications were also recorded. All outcomes were measured at post-operative 1week and at 2years. A total of 26 patients were included in this study. Most patients (92.3%) had Frankel grade D pre-operatively. The rate of neurological deterioration was 15.4% and was correlated with thepresence of dural tear, extra-dural hematoma and spinal cord injury. Pre-operative walking score was prognostic of patients' walking ability in the post-operative period. Intra-operative monitoring of Somatosensory Evoked Potentials (SSEP) was found to be useful for monitoringspinal cord injury in OYL surgery, with a positive predictive value of 100% and anegative predictive value of 92.3%. The false negative rate of a SSEP signal drop was only 7.7% CONCLUSIONS: This is the first study exploring risk factors for post-operative neurological deterioration after surgery for thoracic OYL. The rate of neurological deficit is not small and prognostic factors for poor outcome include poor pre-operative walking score, presence of intra-operative dural tear, extra-dural hematoma and spinal cord injury, and intra-operative drop of SSEP signal.

Reversibility of nerve root sedimentation sign in lumbar spinal stenosis patients after decompression surgery.

The nerve root sedimentation sign (SedSign) is a magnetic resonance imaging (MRI) sign for the diagnosis of lumbar spinal stenosis (LSS). It is included in the assessment of LSS to help determine whether decompression surgery is indicated. Assessment of the reversibility of the SedSign after surgery may also have clinical implications for the decision about whether or not a secondary operation or revision is needed. This study investigated if lumbar decompression leads to a reversal of the SedSign in patients with LSS and a positive SedSign pre-operatively; and if a reversal is associated with more favourable clinical outcomes. If reversal of the SedSign is usual after sufficient decompression surgery, a new positive SedSign could be used as an indicator of new stenosis in previously operated patients. A prospective cohort study of 30 LSS patients with a positive pre-operative SedSign undergoing decompression surgery with or without instrumented fusion was undertaken to assess the presence of nerve root sedimentation (=negative SedSign) on MRI at 3months post-operation. Functional limitation (Oswestry Disability Index, ODI), back and leg pain (Visual Analogue Scale, VAS), and treadmill walking distance were also compared pre- and 3months post-operatively. The short follow-up period was chosen to exclude adjacent segment disease and the potential influence of surgical technique on clinical outcomes at longer follow-up times. 30 patients [median age 73years (interquartile range (IQR) 65-79), 16 males] showed a median pre-operative ODI of 66 (IQR 52-78), a median VAS of 8 (IQR 7-9), and a median walking distance of 0m (IQR 0-100). Three months post-operation 27 patients had a negative SedSign. In this group, we found improved clinical outcomes at follow-up: median post-operative ODI of 21 (IQR 12-26), median VAS of 2 (IQR 2-4), and median walking distance of 1000m (IQR 500-1000). These changes were all statistically significant (p<0.001). Three patients had a positive SedSign at 3-month follow-up due to epidural fat (n=2) or a dural cyst following an intra-operative dural tear (n=1), but also showed improvements in clinical outcomes for ODI, VAS and walking distance. The reversibility of a pre-operative positive SedSign was demonstrated after decompression of the affected segmental level and associated with an improved clinical outcome. A persisting positive SedSign could be the result of incomplete decompression or surgical complications. A new positive SedSign after sufficient decompression surgery could be used as an indicator of new stenosis in previously operated patients.

Thoracic Disc Herniation: 20 Years Experience in 82 Cases

Objective Thoracic disc herniation in uncommon though its surgical management remains challenging topic. Surgery of such disc herniation represents less than 1%to 2% of operation for all disc disease. However, there is no consensus on the best approach and reports are based on small series. Method:This study includes 82 patients with thoracic disc herniation operated in the past 20 years. 71 cases were operated via transthoracic or retopeitonral subdiphargmatic approach and nine through transfacet pedicle sparing route and Two with T1-T2 through low suprasternal notch corridor. In 12 instances two level discs were approached and in one three level, corpectomy was done in 3 cases. Autogenous graft was used in 18 cases, simple cages in 36, expandable cage in three and allograft in the remaining cases. Result Clinical outcome according to the thoracic JOA Score showed significant postoperative improvement. All transfacet pedicle sparing cases and two cases with isolated T1-T2 showed excellent result. six of the anterior group cases were complicated with unilateral paralysis of abdominal wall muscles. Intraoperative dural tear occurred in 4 cases which were sutured. All the patients in this group showed marked recovery except one who was temporarily deteriorated but gradually became better but not fully yet. In two other patients who were wrongly operated with laminectomy and screw fixation no recovery was seen in one but the other one has shown some recovery. In one case where the dura was covered with a thin layer of free fat graft for control of bleeding, overgrowth of fat was observed without any neurology till now. Conclusion Surgery of thoracic disc pose a challenge to the surgeon. The type of the surgery depends on the location of the disc. Centrally located ones and calcified hard ones are best achieved anteriorly But does located laterally via transfacet pedicle spring. Clinical outcome after surgery of a herniated thoracic disc proved successful, especially when the disc consistency, is evaluated before surgery and the affected level intraoperatively. Microscope, patience and the learning curve are important in achieving good result.