Cranial fat dissemination following fat grafting for lumbar dural tear: First case report in the literature

Introduction and importanceDural tear and cerebrospinal fluid (CSF) leak is among the most common complications in lumbar spine surgery. Although primary dural suturing is the preferred method for repair, this is not always achievable specially with ventrolateral tears. Autologous fat grafting is one of the oldest and effective methods for dural repair which can also be used along with other methods of repair. This case report highlights a unique post spinal surgery complication with comment on how to avoid it. To our knowledge, this has not been previously reported in the literature.Case presentationThe authors report a sixty-seven-year-old male with lumbar pseudomeningocele and cranial fat dissemination following fat grafting for non suturable lumbar dural tear. This was demonstrated on magnetic resonance imaging (MRI) after her presented with low-pressure headache.Clinical discussionIntraoperative dural tear is one of the most common complications in spinal surgery. Methods for optimal dural repair including fat grafting have been described but the choice still heavily dependent on the surgeon’s preference and experience. Fat graft can migrate leading to potential undesirable further complications like hydrocephalus and aseptic meningitis.ConclusionCranial fat dissemination following fat grafting for lumbar dural tear should be recognized as a post-operative complication in lumbar spine surgery. It should be considered in case of hydrocephalus or aseptic meningitis post dural fat grafting. Surgeons should utilize adjunct methods to minimize its incidence.     

Symptomatic pneumorachis associated with incidental durotomy during microscopic lumbar disc surgery. Case report

Unintended incidental durotomy is not a rare complication of lumbar microsurgery and is usually recognized and treated immediately. The reconstruction process can be complicated further by unpredictable factors. To their knowledge, the authors report the first case of a symptomatic pneumorachis associated with the accidental awakening of a patient during reconstruction of an incidental durotomy following lumbar microdiscectomy. Incomplete cauda equina syndrome developed in the patient on awakening from surgery after reconstruction of an unintended incidental dural tear that occurred during lumbar microdiscectomy. Symptomatic pneumorachis was revealed on an emergency computed tomography scan, and the patient underwent immediate repeated operation to remove air and decompress the spinal canal. The increasing number and complexity of surgical procedures in the lumbar spine contribute to the growing incidence of unintended durotomy. The surgeon should be aware of rare complications that may arise. Development of a vacuum phenomenon in conjunction with a ball-valve mechanism may lead to pneumorachis during durotomy repair. If this rare complication is promptly recognized and confronted, the outcome will not be associated with long-term sequelae.     

Risk factors for unintended durotomy during spine surgery: a multivariate analysis

Background contextIncidental durotomy during spine surgery is a common occurrence, with a reported incidence ranging from 3% to 16%. Risk factors identified by prior studies include age, type of procedure, revision surgery, ossification of the posterior longitudinal ligament, gender, osteoporosis, and arthritis. However, these studies are largely univariate analyses using retrospectively recorded data.PurposeTo identify and quantify statistically significant risk factors for inadvertent durotomy during spine surgery.Study designMultivariate analysis of prospectively collected registry data. The University of Washington Spine End Results Registry 2003 and 2004 is a compilation of prospectively collected detailed data on 1,745 patients who underwent spine surgery during 2003 to 2004.Patient sampleOne thousand seven hundred forty-five patients underwent spine surgery from 2003 to 2004 at our two institutions.Outcome measuresCardiac, pulmonary, gastrointestinal, neurologic, renal, and urologic complications defined a priori data collection.MethodsUsing these data, univariate and multivariate statistical analyses were performed to identify and quantify risk factors for incidental durotomy during spine surgery. Relative risk (RR) values with valid confidence intervals and p values were determined using these data.ResultsOur multivariate analysis demonstrated that age, lumbar surgery, revision surgery, and elevated surgical invasiveness are significant risk factors for unintended durotomy. Of these, revision surgery was the strongest risk factor for dural tear (RR, 2.21). Diabetes was a significant risk factor in the univariate analysis but not in the multivariate analysis.ConclusionsRevision surgery, age, lumbar surgery, degenerative disease, and elevated surgical invasiveness are significant risk factors for unintended durotomy during spine surgery. These data can be useful to surgeons and patients when considering surgical treatment.     

Use of self-closing U-clips for dural repair in mini-invasive surgery for herniated disc

Object  The feasibility of a new technique of dural repair (self-closing U-clips) in mini-invasive surgery for herniated disk is demonstrated in this case report. Materials and methods  A 44-year-old male patient underwent lumbar microdiscectomy at out Institute, with subsequent dural leak as surgical complication; the dural leak re-appeared even after a second intervention in which we used muscle and dural graft and fibrin glue to repair the leak. We then decided to employ self-closing nitinol- U-clip to achieve primary dural closure. Results  After the intervention the patient no more presented signs or symptoms due to the unintended durotomy, and the postoperative course was uneventful. Conclusion  Self-closing nitinol U-clips (Medtronic, Inc., Minneapolis) can be used for closing a dural tear through a mini-invasive approach that could make a conventional microsuturing technique very difficult.     

Intradural Disc Herniation in the Setting of Congenital Lumbar Spinal Stenosis

IntroductionAccounting for an estimated 1.10-1.76% of all lumbar herniations, lumbar intradural disc herniation (IDH) occurs primarily in males during the fourth to fifth decades of life. While not validated, congenital lumbar spinal stenosis (CLSS) is implicated as one precipitating factor for IDH.Case reportWe report 28-year-old Hispanic female with CLSS, severe obesity, and degenerative disk disease, with a history of minimally invasive surgical (MIS) decompression for a large paracentral L4-5 disc herniation at 25. After three years, the patient developed sudden burning dysesthesias in the L4-5 dermatomes bilaterally and temporary leg weakness. Lumbar magnetic resonance imaging exhibited severe L4-5 spinal stenosis, and the patient underwent repeat MIS decompression, which again provided her with adequate symptom resolution. However, 20 days postoperatively she developed cauda equina syndrome with anal dysfunction, and bilateral leg and foot weakness. Upon open surgical exploration we discovered a tense L4-5 dural protrusion. After a dorsal durotomy, a large IDH with a ventral dural tear was identified. Subsequent to adequate debulking of the IDH, the ventral tear was repaired, and an expansile duraplasty was performed. Overall, the patient's bladder and bowel function, pain, hypoesthesia, and motor strength all improved. Two weeks after surgery she presented with a lumbar pseudomeningocele that was managed conservatively.ConclusionThis report not only highlights an atypical presentation of IDH and is the first case of CLSS linked with IDH, lending support to the hypothesis that CLSS can lead to IDH, but also provides a comprehensive review of IDHs.     

Incidental durotomy during spine surgery: Incidence,management and complications. A retrospective review

Study designRetrospective review of a series of patients who underwent spinal surgery at a single spine unit during a 1 year period.ObjectivesTo assess the incidence, treatment, clinical consequence, complications of incidental durotomy during spine surgery and results of 37 months clinical follow-up.Summary of background dataIncidental durotomy is an underestimated and relatively adverse event during spinal surgery. Several consequences of inadequately treated dural tears have been reported.MethodsA retrospective review was conducted on 1326 consecutive patients who underwent spinal surgery performed in one French spine unit from January 2005 to December 2005. We excluded from this study patients treated for emergency spine cases.ResultsFifty-one dural tears were identified (3.84%). Incidental durotomies were associated with anterior cervical approach in 1 case, with posterior cervical approach in 1 case, with anterior retroperitoneal approach in 1 case and with posterior thoracolumbar approach in 48 cases. In addition, any clinically significant durotomy unrecognised during surgical procedure were included. Thirteen patients presented postoperative complications including 7 cerebrospinal fluid leaks, 2 wound infections, 2 postoperative haematomas, and 2 pseudomeningoceles. Nine of these 13 patients required a revision procedure. A mean follow-up of 37 months showed good long-term clinical results.ConclusionsIncidental durotomy is a common complication of spine surgery. All incidental durotomies must be repaired primarily. Dural tears that were immediately recognised and treated accordingly did not lead to any significant sequelae at a mean follow-up of 37 months. However, long-term follow-up studies will be needed to confirm this finding. The risks associated with dural tears and cerebrospinal fluid leaks are serious and should be discussed with any patients undergoing spine surgery.     

Open epidural blood patch to augment durotomy repair in lumbar spine surgery: surgical technique and cohort study

BACKGROUND CONTEXTIncidental durotomy during elective spine surgery is relatively common. While usually benign and self-limited, it can be associated with morbidity, increased cost, and medicolegal ramifications. Dural repair typically involves performing a primary closure using a suture or dural staple; repairs are then frequently augmented with a sealant, patch, or fat/fascial graft. Although primary repair of an incidental durotomy is standard practice, the ideal secondary sealant or augment choice remains unclear. A wide variety of commercially available dural sealant options exist, and while none have demonstrated consistent superiority, all are associated with single-use costs in the hundreds to thousands of dollars and have concerns regarding swelling, local inflammation, or short-lived dural adherence.PURPOSEThe goal of this study is to compare the results of dural repair augmentation using an open intraoperative epidural blood patch to a hydrogel technique.STUDY DESIGN/SETTINGRetrospective comparative cohort study at an academic referral centerPATIENT SAMPLEAdult patients undergoing lumbar spine surgery from March 2017 to January 2021 who sustained an incidental durotomy. Patients undergoing surgery for infection were excluded.OUTCOME MEASURESThe primary outcome was failure of the repair as determined by a return to the operating room for re-exploration of a persistent cerebrospinal fluid (CSF) leak within 30 days of the index procedure. A secondary outcome was the incidence of a postoperative positional headache, and if present, the method used to obtain resolution. The primary predictor was use of a suture and hydrogel technique (“hydrogel” group), or the use of an epidural blood patch (“EBP” group).METHODSThe method for applying an open epidural blood patch is presented in detail and involves primarily repairing the durotomy followed by allowing whole blood to pool and clot in the operative field until the durotomy is completely covered. This was compared with a group of patients undergoing secondary augmentation with commercially available hydrogel. In both groups, mechanical resistance to CSF leakage was confirmed with direct visualization and a Valsalva maneuver, respectively. Patients were instructed to remain flat until the morning after surgery. Chart review was used for data abstraction on preoperative, demographic, perioperative, and postoperative clinical factors. To compare between the hydrogel and EBP group, Wilcoxon rank-sum testing was used to test for non-parametric comparisons of means, and chi-square testing between binomial data.RESULTSOf 732 patients during the study period, forty-eight patients met study criteria. Twenty-five patients were in the hydrogel group and 23 in the EBP group. Mean age was 69.3 years (standard error 1.3 years). Patients were predominantly female (n = 31, 64.6%) with a mean BMI of 29.5 (SE 0.8), with no significant baseline differences between the hydrogel and EBP groups. Two patients in the hydrogel group (8.0%) and two in the EBP group (8.7%) had mild positional headaches postoperatively that resolved without intervention within 24 hours. One (4.3%) patient in the EBP group had positional headaches following an initial headache-free period; this patient was returned to the operating room and no evidence of a persistent CSF leak was found despite meticulous exploration.CONCLUSIONSAn open, intraoperatively placed epidural blood patch may be an efficacious and cost-effective way to manage an incidental durotomy. This method merits further study as an allergy-free, no swell, cost-neutral method of dural repair augmentation.     

Lag screw fixation of remote bilateral pedicle fractures of the fourth and fifth lumbar vertebrae after a single gunshot wound: a case report and technical pearl

Background contextOf the injuries involving the lumbar spine, pedicle fractures are among the least common; those involving bilateral pedicles are rare.PurposeThe aims of the study were to provide the first documentation of bilateral pedicle fractures at two consecutive levels after a gunshot, to review the mechanism of injury, and to evaluate a nonfusion treatment option for pedicle fractures.Study designThis is a technical note and case report.Outcome measureThe outcome measures were lumbar range of motion, return of motor and sensory functions, and return to normal activities.MethodsA 20-year-old male sustained bilateral pedicle fractures at L4 and L5 with a massive dural tear, progressive neurologic deficits, and urinary incontinence. He underwent repair of the dural tear and lag screw fixation of the pedicle fractures without fusion.ResultsThe patient had full range of motion of his lumbar spine, full strength in his lower extremities, and bladder control.ConclusionsThis is the first report of bilateral multilevel lumbar pedicle fractures after a single penetrating gunshot wound. The case documents this injury pattern after a gunshot, reviews the mechanism of injury, and presents the successful application of a nonfusion treatment option.     

Postoperative management of incidental durotomy in minimally invasive lumbar spinal surgery

Unintended durotomy is a relatively common complication in spine surgery, with a reported incidence up to 14%. Traditional management has been mandatory bed rest for at least 48 h following repair, with or without placement of a drain. With the muscle-splitting approach and decreased potential (dead) space created during minimally invasive spinal surgery (MISS), there is less potential likelihood of symptoms such as spinal headaches or cerebrospinal fluid fistulas. We reviewed the cases of 5 patients undergoing lumbar MISS complicated by an incidental dural tear. Surgical treatment consisted of primary repair and/or use of DuraGen followed by application of either DuraSeal or Tisseel. Although the duration of bed rest varied, postoperative management involved early mobilization less than 48 h after surgery without the use of a drain. One patient was mobilized early on the second postoperative day, 2 patients were mobilized the morning after surgery, and 2 patients were mobilized immediately upon recovery from anesthesia. None of the patients developed symptoms related to durotomy. Although this represents a small series, early postoperative mobilization appears to be a reasonable option and results in shorter hospitalization.     

Evaluation and treatment of dural tears in lumbar spine surgery: a review

Incidental durotomy is a frequent complication of lumbar spinal surgery. The number and complexity of spinal procedures is increasing, leading to a greater prevalence of dural tears; therefore, it is imperative that spine surgeons be familiar with safe and effective closure techniques. Occasionally, a tear may not be recognized during the procedure, so that one must recognize the signs and symptoms of a cerebrospinal fluid leak postoperatively. Several newer treatment concepts show promise. The current study represents an extensive review of the recent literature on the prevalence, mechanism, diagnosis, treatment, and outcomes of dural tears. The authors provide an overview of the problem, an update on current treatment strategies, and describe the senior author's technique of repair, which is easy to do and is effective in stopping additional leakage of cerebrospinal fluid.     

Dural injury following elective spine surgery – A prospective analysis of risk factors,management and complications

Incidental dural tears being a familiar complication in spine surgery could result in dreaded postoperative outcomes. Though the literature pertaining to their incidence and management is vast, it is limited by the retrospective study designs and smaller case series. Hence, we performed a prospective study in our institute to determine the incidence, surgical risk factors, complications and surgical outcomes in patients with unintended durotomy during spine surgery over a period of one year. The overall incidence in our study was 2.3% (44/1912). Revision spine surgeries in particular had a higher incidence of 16.6%. The average age of the study population was 51.6 years. The most common intraoperative surgical step associated with dural tear was removal of the lamina, and 50% of the injuries were during usage of kerrison rongeur. The most common location of the tear was paramedian location (20 patients) and the most common size of the tear was about 1 mm-5mm (31 patients). We observed that the dural repair techniques, placement of drain and prolonged post-operative bed rest didnot significantly affect the post-operative outcomes. One patient in our study developed persistent CSF leak, which was treated by subarachnoid lumbar drain placement. No patients developed pseudomeningocele or post-operative neurological worsening or re-exploration for dural repair. Wound complications were noted in 4 patients and treated by debridement and antibiotics. Based on our study, we have proposed a treatment algorithm for the management of dural tears in spine surgery.     

Natural language processing for automated detection of incidental durotomy

BACKGROUNDIncidental durotomy is a common intraoperative complication during spine surgery with potential implications for postoperative recovery, patient-reported outcomes, length of stay, and costs. To our knowledge, there are no processes available for automated surveillance of incidental durotomy.PURPOSEThe purpose of this study was to develop natural language processing (NLP) algorithms for automated detection of incidental durotomies in free-text operative notes of patients undergoing lumbar spine surgery.PATIENT SAMPLEAdult patients 18 years or older undergoing lumbar spine surgery between January 1, 2000 and June 31, 2018 at two academic and three community medical centers.OUTCOME MEASURESThe primary outcome was defined as intraoperative durotomy recorded in free-text operative notes.METHODSAn 80:20 stratified split was undertaken to create training and testing populations. An extreme gradient-boosting NLP algorithm was developed to detect incidental durotomy. Discrimination was assessed via area under receiver-operating curve (AUC-ROC), precision-recall curve, and Brier score. Performance of this algorithm was compared with current procedural terminology (CPT) and international classification of diseases (ICD) codes for durotomy.RESULTSOverall, 1,000 patients were included in the study and 93 (9.3%) had a recorded incidental durotomy in the free-text operative report. In the independent testing set (n=200) not used for model development, the NLP algorithm achieved AUC-ROC of 0.99 for detection of durotomy. In comparison, the CPT/ICD codes had AUC-ROC of 0.64. In the testing set, the NLP algorithm detected 16 of 18 patients with incidental durotomy (sensitivity 0.89) whereas the CPT and ICD codes detected 5 of 18 (sensitivity 0.28). At a threshold of 0.05, the NLP algorithm had specificity of 0.99, positive predictive value of 0.89, and negative predictive value of 0.99.CONCLUSIONSInternal validation of the NLP algorithm developed in this study indicates promising results for future NLP applications in spine surgery. Pending external validation, the NLP algorithm developed in this study may be used by entities including national spine registries or hospital quality and safety departments to automate tracking of incidental durotomies.     

Practical answers to frequently asked questions in minimally invasive lumbar spine surgery

BACKGROUND CONTEXTSurgical counseling enables shared decision-making (SDM) by improving patients’ understanding.PURPOSETo provide answers to frequently asked questions (FAQs) in minimally invasive lumbar spine surgery.STUDY DESIGNRetrospective review of prospectively collected data.PATIENT SAMPLEPatients who underwent primary tubular minimally invasive lumbar spine surgery in form of transforaminal lumbar interbody fusion (MI-TLIF), decompression alone, or microdiscectomy and had a minimum of 1-year follow-up.OUTCOME MEASURES(1) Surgical (radiation exposure and intraoperative complications) (2)Immediate postoperative (length of stay [LOS] and complications) (3) Clinical outcomes (Visual Analog Scale- back and leg, VAS; Oswestry Disability Index, ODI; 12-Item Short Form Survey Physical Component Score, SF-12 PCS; Patient-Reported Outcomes Measurement Information System Physical Function, PROMIS PF; Global Rating Change, GRC; return to activities; complications/reoperations)METHODSThe outcome measures were analyzed to provide answers to ten FAQs that were compiled based on the authors’ experience and a review of literature. Changes in VAS back, VAS leg, ODI, and SF-12 PCS from preoperative values to the early (<6 months) and late (>6 months) postoperative time points were analyzed with Wilcoxon Signed Rank Tests. % of patients achieving minimal clinically important difference (MCID) for these patient-reported outcome measures (PROMs) at the two time points was evaluated. Changes in PROs from preoperative values too early (<6 months) and late (≥6 months) postoperative time points were analyzed within each of the three groups. Percentage of patients achieving MCID was also evaluated.RESULTSThree hundred sixty-six patients (104 TLIF, 147 decompression, 115 microdiscectomy) were included. The following FAQs were answered: (1) Will my back pain improve? Most patients report improvement by >50%. About 60% of TLIF, decompression, and microdiscectomy patients achieved MCID at ≥6 months. (2) Will my leg pain improve? Most patients report improvement by >50%. 56% of TLIF, 67% of decompression, and 70% of microdiscectomy patients achieved MCID at ≥6 months. (3) Will my activity level improve? Most patients report significant improvement. Sixty-six percent of TLIF, 55% of decompression, and 75% of microdiscectomy patients achieved MCID for SF-12 PCS. (4) Is there a chance I will get worse? Six percent after TLIF, 14% after decompression, and 5% after microdiscectomy. (5) Will I receive a significant amount of radiation? The radiation exposure is likely to be acceptable and nearly insignificant in terms of radiation-related risks. (6) What is the likelihood that I will have a complication? 17.3% (15.4% minor, 1.9% major) for TLIF, 10% (9.3% minor and 0.7% major) for decompression, and 1.7% (all minor) for microdiscectomy (7) Will I need another surgery? Six percent after TLIF, 16.3% after decompression, 13% after microdiscectomy. (8) How long will I stay in the hospital? Most patients get discharged on postoperative day one after TLIF and on the same day after decompression and microdiscectomy. (9) When will I be able to return to work? >80% of patients return to work (average: 25 days after TLIF, 14 days after decompression, 11 days after microdiscectomy). (10) Will I be able to drive again? >90% of patients return to driving (average: 22 days after TLIF, 11 days after decompression, 14 days after microdiscectomy).CONCLUSIONSThese concise answers to the FAQs in minimally invasive lumbar spine surgery can be used by physicians as a reference to enable patient education.     

Case report: Delayed presentation of postural headache in an adolescent girl after microscopic lumbar discectomy

PURPOSE: To discuss the diagnostic and therapeutic challenges presented by an adolescent girl with delayed postural headaches and photophobia that occurred three months after an apparently uncomplicated microscopic lumbar discectomy. CLINICAL FEATURES: A previously healthy girl was admitted to our hospital with a one-week history of an unremitting, frontal-retroorbital postural headache and photophobia. Three months before admission, the patient had undergone a L5-S1 left hemilaminotomy and foraminotomy with microdiscectomy for excision of a herniated intervertebral disc. Conservative treatment failed to provide symptomatic relief. Cranial magnetic resonance imaging showed enhancement of the pachymeninges, consistent with intracranial hypotension. A chronic cerebrospinal leak was identified by high-resolution computed tomography (CT) myelography. Epidural blood patches were performed, with and without CT guidance, that provided temporary relief of the patient's symptoms; however, direct suture plication of the dural tear was eventually required for definitive treatment. CONCLUSION: This case emphasizes that delayed presentation of dural injury may occur after lumbar surgery and describes the potential therapeutic implications for this unusual complication.     

Effect of fibrin glue on the prevention of persistent cerebral spinal fluid leakage after incidental durotomy during lumbar spinal surgery

Approximately one million spinal surgeries are performed in the United States each year. The risk of an incidental durotomy (ID) and resultant persistent cerebrospinal fluid (CSF) leakage is a significant concern for surgeons, as this complication has been associated with increased length of hospitalization, worse neurological outcome, and the development of CSF fistulae. Augmentation of standard dural suture repair with the application of fibrin glue has been suggested to reduce the frequency of these complications. This study examined unintended durotomies during lumbar spine surgery in a large surgical patient cohort and the impact of fibrin glue usage as part of the ID repair on the incidence of persistent CSF leakage. A retrospective analysis of 4,835 surgical procedures of the lumbar spine from a single institution over a 10-year period was performed to determine the rate of ID. The 90-day clinical course of these patients was evaluated. Clinical examination, B-2 transferrin assay, and radiographic imaging were utilized to determine the number of persistent CSF leaks after repair with or without fibrin glue. Five hundred forty-seven patients (11.3%) experienced a durotomy during surgery. Of this cohort, fibrin glue was used in the dural repair in 278 patients (50.8%). Logistic models evaluating age, sex, redo surgery, and the use of fibrin glue revealed that prior lumbar spinal surgery was the only univariate predictor of persistent CSF leak, conferring a 2.8-fold increase in risk. A persistent CSF leak, defined as continued drainage of CSF from the operative incision within 90 days of the surgery that required an intervention greater than simple bed rest or over-sewing of the wound, was noted in a total of 64 patients (11.7%). This persistent CSF leak rate was significantly higher (P < 0.001) in patients with prior lumbar surgery (21%) versus those undergoing their first spine surgery (9%). There was no statistical difference in persistent CSF leak between those cases in which fibrin glue was used at the time of surgery and those in which fibrin glue was not used. There were no complications associated with the use of fibrin glue. A history of prior surgery significantly increases the incidence of durotomy during elective lumbar spine surgery. In patients who experienced a durotomy during lumbar spine surgery, the use of fibrin glue for dural repair did not significantly decrease the incidence of a persistent CSF leak.     

Obesity and recurrent intervertebral disc prolapse after lumbar microdiscectomy

Introduction

The primary aim of this study was to investigate the relationship between obesity and recurrent intervertebral disc prolapse (IDP) following lumbar microdiscectomy.

Methods

A retrospective review of case notes from 2008 to 2012 was conducted for all patients who underwent single level lumbar microdiscectomy performed by a single surgeon. All patients were followed up at two weeks and six weeks following surgery, and given an open appointment for a further six months.

Results

A total of 283 patients were available for analysis: 190 (67%) were in the non-obese group and 93 (32.9%) in the obese group. There was no statistical difference in postoperative infection, dural tear or length of stay between the non-obese and obese groups. Recurrent symptomatic IDP was seen in 27 patients (9.5%) confirmed by magnetic resonance imaging. Nineteen (10.0%) were in the non-obese group and eight (8.6%) in the obese group (p>0.8).

Conclusions

In our study, obesity was not a predictor of recurrent IDP following lumbar microdiscectomy. Our literature review confirmed that this study reports the largest series to date analysing the relationship between obesity and recurrent IDP following lumbar microdiscectomy in the British population.     

Iatrogenic dural tears

A dural tear, or durotomy, is a well-known complication of spine surgery and is among the most common reported complications in spinal surgery with an incidence of 0.5-5%. This text will provide a general review of the relevant anatomy, diagnosis, treatment, and outcomes.     

Combined thrombin and autologous blood for repair of lumbar durotomy

Lumbar durotomy can be intended or unintended and can result in persistent cerebrospinal fluid (CSF) leak. Several methods are used to manage this complication including bed rest and CSF diversion. In this study, we theorize that the use of thrombin-soaked gel foam together with autologous blood laid on the sutured dural tear can prevent persistent CSF leak. A retrospective review of the records of patients who underwent lumbar surgery and had an unintended dural tear with CSF leak, comparing the outcome of patients who were submitted to thrombin-soaked gel foam together with autologous blood (group A) to patients treated by subfacial drain, tight bandage, and bed rest (group B). A total of 1371 patients had lumbar surgery, of whom 131 had dural tear. Group A included 62 patients, while group B included 69 patients. 8.1 % of group A patients had CSF leak as compared to 17.4 % of group B patients at postoperative day 14. The incidence of postoperative CSF leak and duration of postoperative hospital stay were statistically lower in group A than in group B (p?<?0.05). Combining thrombin and autologous blood for repair of lumbar durotomy is an effective and a relatively cheap way to decrease CSF leak in the early postoperative period as well as decreasing postoperative hospital stay. It also resulted in decreased complications rate in the late postoperative period.     

Unrecognized durotomy after lumbar discectomy: a report of four cases associated with the use of ADCON-L

STUDY DESIGN: This report describes four cases of symptomatic cerebral spinal fluid leak after lumbar microdiscectomy where ADCON-L was used. OBJECTIVES: To report that ADCON-L may exacerbate cerebral spinal fluid leak from unrecognized, small dural tears after lumbar discectomy. SUMMARY OF BACKGROUND DATA: ADCON-L is a porcine-derived polyglycan that is used with increasing frequency in spinal surgery. It is advocated to reduce postoperative peridural fibrosis and adhesions. METHODS: Four cases of symptomatic cerebral spinal fluid leak after lumbar microdiscectomy were identified. Information on these patients was obtained by chart review. RESULTS: Three patients had small, inadvertent durotomies that were not appreciated at surgery even with the aid of a microscope. The dural violation in the fourth patient occurred at the previous epidural steroid injection site located on the contralateral side of the laminotomy. CONCLUSION: ADCON-L may inhibit dural healing and exacerbate cerebral spinal fluid leak from microscopic durotomies not recognized at the time of surgery.     

Incidence,prognosis, and risk factors for bladder and bowel dysfunction due to incidental dural tears in lumbar microendoscopic surgery

BACKGROUND CONTEXTDespite the common occurrence of incidental dural tears, the incidence and prognosis of bladder and bowel dysfunction (BBD) due to incidental dural tears in lumbar spinal surgery are not well known because of the lack of reported cases.PURPOSETo analyze the incidence, prognosis, and risk factors for BBD after lumbar microendoscopic surgery with or without incidental dural tears.STUDY DESIGN/SETTINGA retrospective cohort study.PATIENT SAMPLEWe analyzed 2,421 patients who underwent lumbar microendoscopic surgery and investigated patients with BBD after an incidental durotomy during surgery.OUTCOME MEASURESPatients were divided into three groups on the basis of dysuria and defecation disorders: severe BBD, mild BBD, and no BBD. The post void residual volumes before and after surgery were compared using an ultrasound bladder scanner or bladder catheterization after confirmation of urination. Bowel dysfunction was evaluated by subjective symptomatic deterioration and the increase in the frequency and duration of postoperative medical care.METHODSRisk factors for BBD were analyzed using surgical video documentation to determine the dural tear site and cauda equina exposure from the dural sac. Patients with BBD were prospectively followed up for prognosis determination. The chi-square test was used to compare the incidence of BBD between patients with dural tears and those without. Propensity score-adjusted logistic regression analysis was performed to evaluate the effects of various factors on the incidence of postoperative BBD.RESULTSThe incidence of dural tears was 6.9% (168/2,421). The overall incidence of BBD was 3.0% (73/2,421), while the incidences of BBD (mild+severe BBD) and severe BBD due to incidental dural tears were 1.2% (30/2,421) and 0.8% (20/2,421), respectively. The incidence of BBD in patients with dural tears and those without tears was 17.9% [30/168] and 1.9% [43/2,253; p<.001]), respectively. BBD rates at 1 week, 1 month, 3 months, 6 months, and 1 year after surgery were 64.0%, 44.0%, 40.0%, 28.0%, and 13.6%, respectively. Logistic regression analysis revealed that the male sex (odds ratio [OR], 4.20), dural tears in the central area (OR, 10.15), and exposure of the cauda equina (OR, 51.04) were significant risk factors.CONCLUSIONSThe incidence of dural tears in lumbar microendoscopic surgeries are associated with an increased incidence of BBD. The recovery rate for BBD due to incidental dural tears is generally good; however, some patients experience long-term symptoms. Clinicians should be aware that incidental dural tears with cauda equina exposure can increase the risk of BBD.