Incidental Durotomy Research Articles

Cauda Equina Compression by Hydrogel Dural Sealant After a Laminotomy and Discectomy

The authors present a case of cauda equina compression after laminotomy and discectomy where incidental durotomy was managed with the application of hydrogel sealant. The patient reported return of radicular symptoms on the first postoperative day, and deterioration to early cauda equina syndrome after bending on the sixth day. To demonstrate that in addition to its recognized volume expansion properties, that the product has the ability to migrate and produce symptoms remote from where it was inserted. The physical properties of DuraSeal (Confluent Surgical, Waltham, MA), a hydrogel dural sealant, make it an effective adjunct to dural closure. Its volume expansion has been associated with neural compression after posterior fossa decompression. We have found no reported migration of this product. Sequential postoperative imaging shows swelling and migration of the hydrogel into spinal canal with resultant compression. Exploration on postoperative day 10 revealed sealant causing cauda equina compression proximal to the site of the durotomy. The authors recommend that in addition to caution regarding its potential mass effect, that cognizance be taken of the product's potential to migrate and result in symptoms at a distant site.

100 consecutive cases of degenerative lumbar conditions using a non-threaded locking screw system with a 90-degree locking cap.

BackgroundThis prospective study analyzes the perioperative outcomes and long-term fusion success of 100 consecutive lumbar degenerative cases. The cases were managed using a non-threaded locking screw system, in conjunction with polyetheretherketone (PEEK) cages, for posterior lumbar interbody fusion (PLIF) procedures. These 100 cases were compared to another prospective study treating patients with the same inclusion and exclusion criteria using conventional plate-based pedicle screw spinal instrumentation augmented with carbon fiber interbody cages.MethodsA total of 167 operative levels were treated in 100 patients (51 single-level, 39 two-level and 10 three-level cases). Eleven cases were revisions and 67 patients received interbody fusion cages. Patients had an average of 22.8 ± 4.0 months followup. Results: There was one instrumentation failure but no significant subsidence at the interbody fusion level. The disc space height was restored as part of the surgical procedure at the interbody cage levels: from 7.5 ± 2.3 mm preoperative to 9.0 ± 2.1 mm postoperative. There were 2 cases of pseudarthrosis (2 / 100 = 2%). The average operative time for 1-level cases was 111 ± 25 minutes; for 2-level cases it was 132.4 ± 21.8 minutes; and for 3-level cases it was 162.6 ± 33 minutes. Blood loss averaged 800 ± 473 cc for 1-level cases, 1055 ± 408 cc for 2 levels, and 1155 ± 714 cc for 3 levels. The length of stay was similar between the 3 groups (4.4 ± 1.2 days for single-level cases, 4.7 ± 1.1 for 2 levels, and 5.0 ± 1.1 for 3 levels; P > .05). There were 3 incidental durotomies, and 4 other patients developed infections postoperatively that required reoperation.ConclusionThe disc and foraminal heights can be restored and maintained with a unilateral cage and pedicle screw construct. Unilateral transforaminal lumbar interbody fusion using a PEEK cage combined with a non-threaded locking pedicle screw and rod system results in similar fusion rates to those achieved using the bilateral Brantigan interbody fusion cage or a single BAK Vista implant. When compared to the bilateral Brantigan cages, decreased operative time (P < .001), decreased blood loss (P < .001) and reduced incidence of dural tears (P < .001) are advantages of using a non-threaded locking screw system and single PEEK interbody cage for lumbar degenerative conditions without compromising subsequent fusion rates.

Leakage of cerebrospinal fluid and secondary intracranial infection induced by Cloward technique of cervical discectomy and fusion: presentation and treatment

Cloward technique of cervical discectomy and fusion is a long and complex surgical procedure and instrumentation, by which complicated infection is rare in an era of routine prophylactic antimicrobial agent, especially in procedures by anterior approach. A study in the journal of Spine suggested that the incidence of unintentional laceration of the dura mater during spinal surgery might be as high as 14%.1 A majority of them are repaired intraoperatively and/or present as a spontaneous process of healing. Therefore, leakage of cerebrospinal fluid (CSF) and secondary intracranial infection induced by incidental durotomy are rare. Levi et al.2 reviewed spinal instrumentation procedures in 452 cases at a single institution, finding that 17 patients got infections in the operative areas. Infection occurred after posterior spinal instrumentation procedures (7.2%) and no infection was found after anterior instrumentation procedures regardless of the vertebral levels. Likewise, Aydinli et al.3 reported that 8 patients were complicated by acute infection out of 174 patients undergoing instrumented spinal surgery, including no anterior procedures. To our knowledge, we are the first to report a complete clinical course concerning CSF leakage and secondary intracranial infection induced by Cloward technique of cervical discectomy and fusion.

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.

Delayed Symptoms of Cerebrospinal Fluid Leak Following Lumbar Decompression

Numerous reports in the literature describe cerebrospinal fluid (CSF) leaks resulting from dural tears; however, most of these reports document symptoms of incidental durotomy occurring ,48 hours postoperatively. This case report describes patients with symptoms of CSF leak occurring a few days to a few weeks after lumbar spine surgery who required additional surgery to repair the dura and alleviate their symptoms. Records for patients who had lumbar spine surgery performed by 2 spine surgeons at a single institution between 1990 and 2005 were reviewed. After additional surgery to repair what appeared to be late postoperative durotomies, 2 patients recovered fully from their orthostatic headaches and reported satisfactory relief of their preoperative neurological symptoms. They did not have symptoms of spinal fluid leakage following surgery, and no intraoperative dural tear was noted, suggesting these cases may have been secondary to late postoperative durotomy. The incidence of durotomy has been noted to be increased in patients undergoing revision spine surgery secondary to adhesions and scarring of the dura. As this was the first spine operation for both cases reported, we believe that residual bone spikes are responsible for puncturing the dural sac postoperatively. Spine surgeons should be exceedingly cautious in inspecting for bone spikes following an extensive dural exposure and recognize the significance of the new onset of an orthostatic headache, even days or weeks following spine surgery.

Intracranial Hemorrhage Following Incidental Durotomy During Spinal Surgery

Unintentional durotomy is a frequent complication of spinal surgical procedures, with a rate as high as 17%1-5. With appropriate management, the long-term outcomes for patients who had an unintended durotomy were no different from those for patients who underwent a similar surgery without complications6,7. A small percentage of patients with unintentional durotomy sustain intracranial hemorrhage, likely due to an alteration in intradural hydrostatic dynamics caused by cerebrospinal fluid hypovolemia3,4,8,9. Despite the gravity of this complication, to our knowledge, only six cases have been previously documented3,8-11. All neurosurgeons and orthopaedic surgeons at a large tertiary care center associated with a major university were solicited to identify cases of intracranial hemorrhage following incidental durotomy that occurred during the period of 1996 to 2006. The purpose of this report is to describe the four identified patients who sustained intracranial hemorrhage following an unintentional durotomy during posterior thora-columbar spinal surgery and to discuss the importance of our findings. The patients were informed that data concerning the case would be submitted for publication, and they consented. CASE 1. A seventy-seven-year-old man with a history of ankylosing spondylitis and a daily intake of 325 mg of aspirin presented with a thoracic kyphosis of 110° that impaired his ability to perform activities of daily living. He was brought to the operating room for posterior arthrodesis and instrumentation from T11 to S1 as well as L2 pedicle subtraction osteotomy. During posterior dissection, a dural tear was made, resulting in a substantial loss of cerebrospinal fluid. The dura was absent at the apex of the deformity and was friable elsewhere. After an intraoperative neurosurgical consultation was obtained, the dural rent was covered with DuraGen (Integra LifeSciences, Plainsboro, …

Intracranial Hemorrhage Following Incidental Durotomy During Spinal Surgery

Intracranial Hemorrhage Following Incidental Durotomy During Spinal Surgery

Incidental Durotomy in Cervical Spinal Surgery

Incidental durotomy complicating cervical spinal surgery is not an uncommon occurrence. While most often these unintentional breeches of the thecal sac do not lead to significant sequelae, there is evidence that they cannot be considered entirely benign events. Meticulous, watertight closure of the dural tear intraoperatively remains the best prevention of continued cerebrospinal fluid egress postoperatively. If complications of dural-cutaneous cerebrospinal fluid fistulas and/or pseudomeningoceles do develop postoperatively, several conservative maneuvers are available. However, a reoperation may still be required as the definitive treatment.

Symptomatic pneumorachis associated with incidental durotomy during microscopic lumbar disc surgery

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.

The Long-term Clinical Sequelae of Incidental Durotomy in Lumbar Disc Surgery

A retrospective, long-term follow-up study. To find out whether incidental durotomy in lumbar disc surgery is associated with long-term sequelae. Incidental durotomy is a frequent complication during spinal surgery. Little is known about the clinical long-term outcome. The study population comprised 1,280 patients who underwent standard discectomy of a lumbar disc herniation. A total of 41 patients with incidental durotomies (Group A) were compared with a control group (n = 41) (Group B) matched for age, sex, spinal level, and duration of follow-up. After a mean follow-up period of 10.2 years (Group A) or 10.3 years (Group B), the patients reported complaints, headache, and low back or leg pain. The patients' activity was assessed by means of a questionnaire concerning hindrance in daily activities, the Tegner score for general activities in daily life, and the Hannover Functional Ability Questionnaire for Measuring Back Pain-Related Functional Limitations (FFbH-R). The frequency of reoperation and the intake of analgesics were included. Furthermore, the patients' inability to work, change of profession, and retirement were registered. Patients with incidental durotomy had a poorer outcome after surgery. The Tegner score was significantly decreased for the group with dural tears. Furthermore, significant more patients with incidental durotomy complained about headaches after surgery. A strong tendency for worse outcome in Group A was shown in regard to reported complaints and daily activity. The patients with incidental durotomy had a tendency to more reoperations, a longer duration of inability to work, more back-pain, and functional limitations related to back-pain (FFbH-R). Our study revealed that incidental durotomy in lumbar disc surgery was associated with long-term clinical sequelae. We therefore conclude that dural tears bring about poor clinical outcome at the long-term follow-up.

The Indications for Interbody Fusion Cages in the Treatment of Spondylolisthesis

This study retrospectively examines outcomes of unilateral transforaminal lumbar interbody fusion (TLIF) with posterior fixation using anterior carbon fiber cages and 360 degrees fusion in spondylolisthesis. The goals were to examine the outcomes and perioperative complications of using anterior column support in the treatment of various types of spondylolisthesis. In 2000, Brantigan et al reported the Brantigan interbody fusion cage used as a posterior lumbar interbody fusion in the US IDE clinical trial. This is the largest series to date of TLIF cages specifically used in the treatment of spondylolisthesis. A comprehensive long-term follow-up study was conducted to evaluate the fusion success and morbidity following implantation with an anterior column support and posterior pedicle screw fixation. The 120 patients with spondylolisthesis were comprised by 11 cases, dysplastic; 58 cases, degenerative; and 51 cases, isthmic-acquired spondylolisthesis. Anterior column support was either a rectangular carbon fiber/PEEK device or a cylindrical carbon fiber/PEEK device. Twenty-eight cases (23%) were revisions. There were no pseudarthrosis, instrumentation failures, or significant subsidence at the TLIF level. The disc space height and foraminal height were restored as part of the surgical procedure. Disc height, as measured from the posterior edge of the superior vertebral body, increased from a mean of 5.6 mm before surgery to a mean of 9.3 mm after surgery. Although reduction of the slip was not the primary goal during the surgical procedure for the 120 cases with spondylolisthesis (isthmic-acquired = 51, degenerative = 58, and dysplastic = 11), the 23% slip reduction achieved at surgery was maintained at follow-up. Mean operative time was 143 +/- 33 minutes (range, 70-255 minutes) for all cases. Mean blood loss was 724 +/- 431 mL (range, 300-2,500 mL). There were seven incidental durotomies and three infections. One patient with Grade I degenerative spondylolisthesis required revision of the carbon fiber cage for posterior migration secondary to a traumatic event 3 months after surgery. Fusion success was 98% using the criteriaof Lenke for the posterior fusion and Brantigan and Steffee for the TLIF graft incorporation. Interbody cages in spondylolisthesis are useful to increase neuroforaminal height, to facilitate reduction, and to improve the chances of achieving a successful 360 degrees fusion.

Cerebral vasospasm following intracranial hypotension caused by cerebrospinal fluid leak from an incidental lumbar durotomy

The authors report on the unusual case of a patient with intracranial hypotension following an incidental durotomy complicated by an extensive but reversible cerebral vasospasm. Despite the dural tear repair and correction of the intracranial hypotension, the vasospasm ran its course. The precise mechanism of the cerebral vasospasm in this patient is unclear.

Collagen Matrix (DuraGen) in Dural Repair: Analysis of a New Modified Technique

Retrospective review of 110 patients undergoing spinal dural repair and regeneration using an onlay, suture-free, 3-dimensional-collagen matrix graft (DuraGen) over an 8-year period (1995-2003). Technique appraisal of collagen matrix to repair spinal dura following incidental durotomy, spinal tumor surgery, and trauma. Traditional methods of spinal dural repair following incidental durotomy involve tedious attempts at primary watertight suture with a 5% to 10% failure rate. Dural injury occurs after trauma, or dural excision may be required after tumor resection. Collagen matrix is a newer development in collagen sponge. The clinical and demographic data included diagnosis, type and site of surgery, infection risk, size of defect, use of lumbar drains, closed suction subfascial drains, and adverse events. The primary endpoints of graft failure were cerebrospinal fluid leak and pseudomeningocele formation. Neurosurgical wound infection rates were determined. Collagen matrix was used (n = 110) in the following conditions: degenerative (69), pseudomeningocele formation repair (4), tumors (14), trauma (13), and congenital (5). There were 15 cervical (10 anterior), 21 thoracic (3 anterior), and 71 lumbar (all posterior) surgeries. Fibrin glue was used in 7.3%, subfascial drains in 82%, and lumbar drainage in 2.7%. Overall, cerebrospinal fluid leaks occurred in 2.7%. The 2 pseudomeningocele formations (3.2%) resolved at 3 months. There were 2 wound infections. In the subgroup with incidental durotomy (n = 69), failure of cerebrospinal fluid containment occurred in 4.3% [1 cerebrospinal fluid leak (1.4%), 2 pseudomeningocele formations (2.9%)]. Collagen matrix was successful in cerebrospinal fluid containment in > 95% of patients requiring dural repair following anterior and posterior spinal surgery. Subfascial drains were safe. Routine lumbar drains are not required but are recommended for repair of established pseudomeningocele formations.

Epidural Abscess and Discitis Complicating Instrumented Posterior Lumbar Interbody Fusion: A Case Report

A case of epidural abscess and discitis following instrumented PLIF using a single carbon fiber interbody cage is presented. To describe a previously unreported complication of epidural abscess and discitis following posterior lumbar interbody fusion using a single carbon fiber cage. Various complications have been reported with PLIF. These include graft migration, pseudarthrosis, implant subsidence, epidural hemorrhage, incidental durotomy, arachnoiditis, transient or permanent neurologic deficits, persistence of pain, and wound infections. There are no reported cases of epidural abscess or refractory discitis associated with PLIF. A 35-year-old infantryman on active duty with chronic low back pain and single-level lumbar disc degeneration underwent instrumented PLIF after reporting no improvement with 3 years of extension-based physical therapy and nonsteroidal pain medications. His back pain was reported improved at 6 weeks after surgery. At 12 weeks after surgery, he presented to the emergency department with intense back pain and fevers. Laboratory data were remarkable for elevated erythrocyte sedimentation rate (118) and C-reactive protein (38). Initial imaging studies, including a lumbar MRI, did not demonstrate any abnormalities. The patient continued to spike fevers, and a repeat lumbar MRI 1 week later clearly demonstrated the presence of an epidural abscess at the level of the PLIF surgery. The patient was treated with surgical debridement and epidural abscess drainage. The interbody cage was left in place. Surgical cultures identified Staphylococcus aureus as the pathogen, and the patient was placed on intravenous vancomycin. During the ensuing 3 weeks, his clinical symptoms worsened and his radiographs demonstrated lucency in the region of his interbody cage. Repeat debridement was performed, and his interbody cage and pedicle screw instrumentation were removed 4 months after initial surgery. The disc space infection resolved following removal of the implants. Radiographs at 6 months after instrumentation removal demonstrated solid bilateral posterolateral arthrodesis. The patient returned to active duty 1 year after his initial surgery, reporting that his back pain was reduced compared with his preoperative level. There is a paucity of literature on epidural abscess and discitis as complications associated with PLIF. In this case, the infection persisted despite surgical debridement and intravenous antibiotics. The patient ultimately required removal of the interbody implant and posterior instrumentation. The patient developed solid posterolateral arthrodesis despite the presence of deep infection, which led to early implant removal 4 months after the initial surgery. This case underscores the potential importance of concomitant posterolateral fusion, particularly following wide laminectomy and facetectomy required for PLIF.

Incidental durotomy in lumbar spine surgery: incidence and management

There is increasing awareness of the need to inform patients of common complications that occur during surgical procedures. During lumbar spine surgery, incidental tear of the dural sac and subsequent cerebrospinal fluid leak is possibly the most frequently occurring complication. There is no consensus in the literature about the rate of dural tears in spine surgery. We have undertaken this study to evaluate the incidence of dural tears among spine surgeons in the United Kingdom for commonly performed spinal procedures. Prospective data was gathered for 1,549 cases across 14 institutions in the United Kingdom. The results give us a baseline rate for the incidence of dural tears. The rate was 3.5% for primary discectomy, 8.5% for spinal stenosis surgery and 13.2% for revision discectomy. There was a wide variation in the actual and estimated rates of dural tears among the spine surgeons. The results confirm that prospective data collection by spine surgeons is the most efficient and accurate way to assess complication rates for spinal surgery.

The related outcome and complication rate in primary lumbar microscopic disc surgery depending on the surgeon's experience: comparative studies

Background context Studies concerning intraoperative complications and their influence on the clinical outcome of microscopic disc surgery are quite rare. Complication rates vary between 1.5% and 15.8%. A correlation between the surgeon's experience and the complication rate may be expected. Purpose To determine the influence of the surgeon's experience on the intraoperative complication rate in lumbar microscopic disc surgery. Study design Three studies are included: 1) retrospective analysis of intraoperative complications in microscopic disc surgery (N = 1,872); 2) prospective follow-up study of microscopic disc surgery (N = 583); 3) prospective evaluation of complication rates in microscopic disc surgery (N = 90). Patient sample Patient data sets from 1,872 lumbar microscopic disc surgeries performed between January 7, 1981, and June 31, 2000, were examined in a retrospective study. A total of 463 patients, operated on between 1991 and 1996, were followed up by a questionnaire. Finally, a prospective controlled trial (N = 90) was performed. Outcome measures Such complications as incidental durotomy, wrong level exposure, or bleeding were analyzed based on the patient data sets by a blinded external evaluator. The rates of lower back pain and ischiatic pain were measured on a visual analogue scale at follow-up in Study 2 and Study 3. To measure the outcome of surgery in daily life activities and functional capacity, the Tegner activity level was calculated. In addition, a questionnaire with the Hannover score was used. The patient's social and economic status was also recorded. Methods A total of 1,872 lumbar microscopic disc surgeries, performed between January 7, 1981 and June 31, 2000, were examined in a retrospective study. Intra- and perioperative complications were evaluated and related to the surgeons' level of experience. Patients in the first group (XL) were operated on by the most experienced surgeon (more than 500 microscopic discectomies before the beginning of the study). The L-group surgeons performed between 50 and 100 microscopic disc surgeries before the study. This group included a total number of seven surgeons during the 1981–2000 time frame. None of this group reached the experience level of 500 surgeries during the course of the study. A total of 463 patients, operated on between 1991 and 1996, were followed up. Finally, a prospective controlled trial (N = 90) was performed. Injuries of the dura, nerve root, ventral structures and wrong level exposure, which had been detected and corrected during surgery, were analyzed. In the second and third study, the outcome was correlated to surgery and complications during surgery. Results The rate of intraoperative complications showed a statistically significant difference between the groups. The comparison of both groups (n = 1,872) with regard to the rate of intraoperative complications showed a statistically significant difference between 2.2% in the XL group and 10.7% in the L group (p≤.001). Regarding work-related and socioeconomic factors, no significant difference in the outcome was seen. Conclusions Microscopic disc surgery requires a course of instruction and a considerable number of surgeries under supervision by experienced surgeons. To shorten the learning curve, a number of standardized surgery steps to clearly identify anatomical landmarks are helpful. During training, these landmarks can be checked by an experienced surgeon to minimize the rate of intraoperative complications. Initial postoperative ischiatic pain was correlated to an incidental durotomy with p<.001. For long-term results after disc surgery, however, socioeconomic and work-related factors are of greater importance in spinal disc surgery than the incidence of intraoperative complications.

Spinal pseudomeningoceles and cerebrospinal fluid fistulas.

Spinal pseudomeningoceles and cerebrospinal fluid (CSF) fistulas are rare extradural collections of CSF that result following a breach in the dural-arachnoid layer. They may occur due to an incidental durotomy, during intradural surgery, or from trauma or congenital abnormality. The majority are iatrogenic and occur in the posterior lumbar region following surgery. Although they are often asymptomatic, they may cause low-back pain, headaches, and even nerve root entrapment. Leakage of CSF from the wound may cause a fistulous tract, which is a conduit for infection and should be repaired immediately. Diagnosis can be confirmed on clinical examination or imaging studies including magnetic resonance imaging, computerized tomography myelography, and radionuclide myelography. Treatment must be specific to each patient because the timing, size, symptoms, and location of the dural breach all affect the choice of therapy. Nonsurgical methods may be used, but more frequently operative repair is required. In this article, the authors review the diagnosis and treatment of spinal pseudomeningoceles and CSF fistulas.

Complications of revision spinal surgery.

Surgical treatment for symptomatic cervical and lumbar spondylosis has become prevalent in recent years. With this increased intervention, increasing numbers of patients experience persistent symptoms and require revision spinal surgery. Although many aspects of the workup and operation are similar for both primary and revision surgery, there are special considerations that must be examined when determining if a patient is a candidate for revision surgery. Preoperative workup should include evaluation for spinal instability. Intraoperatively, scar tissue may complicate the procedure, and care must be taken to avoid incidental durotomy. The prognosis for a revision surgery can be predicted best by the patient's outcome after the primary surgery. As with any surgical procedure, patient selection is imperative for successful outcome.

P63. Collagen matrix (Duragen) in spinal durotomy: technique appraisal and clinical results

HYPOTHESIS: Incidental durotomy occurs in 0.3–13% of spinal surgery & up to 18% in re-operation, often aggravated by epidural scarring, with a prevalence rate of 5% despite meticulous attention to surgical technique, Grafts may also be required to reconstitute the dura after resection of tumors e.g. meningiomas, following penetration by bony fragments of fractures, penetrating trauma or even to augment primary dural repair. Repair of torn dura is time consuming and often difficult to repair especially lateral and anterior tears. Traditional methods of spinal dural repair involve tedious attempts at primary watertight suturing augmented by synthetic or biological grafts.

Incidental Dural Tear during Posterior Surgery of Degenerative Lumbar Disease

‐ Abstract ‐ Study Design : A retrospective study. O b j e c t i v e : To analyze the clinical features and prognosis of intraoperative incidental durotomy during posterior surgery for degenerative lumbar disease. In addition, we tried to evaluate clinical outcome and safety of skillful neglect of pin point dural tear. Summary of literature review : Incidental durotomy is one of the most common complications during the operation of degenerative lumbar disease. It may cause signs and symptoms of cerebrospinal fluid leakage and complications such as meningitis, wound infection, pseudomeningocele and fistula. From the literature review, primary repair is mandatory even in the case of pin point dural tear. Materials and methods : Seven hundred fifty-five patients with degenerative lumbar disease, who were operated posteriorly from Jan. 1990 to Feb. 2002, were reviewed retrospectively. Primary operations were 378 cases of laminectomy without instrumentation and 377 cases of decompression and instrumented fusion. Of these patients, 44 (6 percent) sustained an incidental dural tear. We analyzed the mechanisms of dural tear, intraoperative treatment, postoperative management and clinical outcome. Results : Eight cases (2.1%) of dural tears occurred during discectomy, 36 (9.5%) during instrumentation and fusion, and 12 (20%) during revision surgery. Dural tears were treated intraoperatively by primary repair in 20 cases, by fascial graft in 2 and without repair (skillful neglect) in 22. There were no cases of persistent cerebrospinal fluid leakage or fistula formation, and the symptoms of cerebrospinal fluid leakage were transient. Of 36 patients followed for more than one year, 82% had good or excellent result. C o n c l u s i o n : Incidental durotomy occurred in 5.8 percent of lower back surgery patients, and more frequently in revision surgery. Very small dural tears did not have significant influence on the clinical outcome, whether they were repaired or not. Skillful neglect of pin point dural tear may be a reasonable treatment option.