Manish K. Kasliwal

Rates and causes of mortality associated with spine surgery based on 108,419 procedures: A review of the scoliosis research society morbidity and mortality database

Study Design. A retrospective review of a prospectively collected database. Objective. To assess rates and causes of mortality associated with spine surgery. Summary of Background Data. Despite the best of care, all surgical procedures have inherent risks of complications, including mortality. Defining these risks is important for patient counseling and quality improvement. Methods. The Scoliosis Research Society Morbidity and Mortality database was queried for spinal surgery cases complicated by death from 2004 to 2007, including pediatric (younger than 21 yr) and adult (21 yr or older) patients. Deaths occurring within 60 days and complications within 60 days of surgery that resulted in death were assessed. Results. A total of 197 mortalities were reported among 108,419 patients (1.8 deaths per 1000 patients). Based on age, rates of death per 1000 patients for adult and pediatric patients were 2.0 and 1.3, respectively. Based on primary diagnosis (available for 107,996 patients), rates of death per 1000 patients were as follows: 0.9 for degenerative (n = 47,393), 1.8 for scoliosis (n = 26,421), 0.9 for spondylolisthesis (n = 11,421), 5.7 for fracture (n = 6706), 4.4 for kyphosis (n = 3600), and 3.3 for other (n = 12,455). The most common causes of mortality included: respiratory/pulmonary causes (n = 83), cardiac causes (n = 41), sepsis (n = 35), stroke (n = 15), and intraoperative blood loss (n = 8). Death occurred prior to hospital discharge for 109 (79%) of 138 deaths for which this information was reported. The specific postoperative day (POD) of death was reported for 94 (48%) patients and included POD 0 (n = 23), POD 1–3 (n = 17), POD 4–14 (n = 30), and POD >14 (n = 24). Increased mortality rates were associated with higher American Society of Anesthesiologists score, spinal fusion, and implants (P < 0.001). Mortality rates increased with age, ranging from 0.9 per 1000 to 34.3 per 1000 for patients aged 20 to 39 years and 90 years or older, respectively. Conclusion. This study provides rates and causes of mortality associated with spine surgery for a broad range of diagnoses and includes assessments for adult and pediatric patients. These findings may prove valuable for patient counseling and efforts to improve the safety of patient care.

Infection with spinal instrumentation: Review of pathogenesis, diagnosis, prevention, and management.

Background: Instrumentation has become an integral component in the management of various spinal pathologies. The rate of infection varies from 2% to 20% of all instrumented spinal procedures. Every occurrence produces patient morbidity, which may adversely affect long-term outcome and increases health care costs. Methods: A comprehensive review of the literature from 1990 to 2012 was performed utilizing PubMed and several key words: Infection, spine, instrumentation, implant, management, and biofilms. Articles that provided a current review of the pathogenesis, diagnosis, prevention, and management of instrumented spinal infections over the years were reviewed. Results: There are multiple risk factors for postoperative spinal infections. Infections in the setting of instrumentation are more difficult to diagnose and treat due to biofilm. Infections may be early or delayed. C Reactive Protein (CRP) and Magnetic Resonance Imaging (MRI) are important diagnostic tools. Optimal results are obtained with surgical debridement followed by parenteral antibiotics. Removal or replacement of hardware should be considered in delayed infections. Conclusions: An improved understanding of the role of biofilm and the development of newer spinal implants has provided insight in the pathogenesis and management of infected spinal implants. This literature review highlights the mechanism, pathogenesis, prevention, and management of infection after spinal instrumentation. It is important to accurately identify and treat postoperative spinal infections. The treatment is often multimodal and prolonged.

Short-term complications associated with surgery for high-grade spondylolisthesis in adults and pediatric patients: a report from the scoliosis research society morbidity and mortality database.

BACKGROUND Although it is generally agreed upon that surgery for high-grade spondylolisthesis (HGS) is associated with more complications than low-grade spondylolisthesis, its description is primarily based on case reports and relatively small case series. OBJECTIVE To assess short-term complication rates associated with the surgical treatment of HGS in pediatric and adult patients and to identify factors associated with increased complication rates. METHODS All cases of HGS from the Scoliosis Research Society Morbidity and Mortality database for the year 2007 were reviewed. Patients were classified as pediatric (≤18 years) or adult (>18 years). Complications were tabulated, and the rates were compared between the patient groups and based on clinical and surgical factors. RESULTS 165 cases of HGS were reported (88 pediatric, 77 adult). There were 49 complications (29.7%) in 41 patients (24.8%), with no difference in the proportions of pediatric vs adult patients with a complication (P = .86). Occurrence of new neurological deficit after surgery was the most common complication, seen in 19 (11.5%) patients. Performance of an osteotomy was associated with a higher incidence of new neurological deficits in both adult and pediatric groups (P = .02 and P = .012, respectively). Although most of the new neurological deficits improved over follow-up, 10% had no improvement. CONCLUSION This study provides short-term complication rates associated with surgical treatment for HGS in adult and pediatric patients and may prove valuable for patient counseling, surgical planning, and in efforts to improve the safety of patient care.

Minimally invasive retropleural approach for central thoracic disc herniation.

BACKGROUND The management of symptomatic thoracic disc herniation (TDH) has evolved tremendously ever since the first laminectomy was performed. The last decade has witnessed the evolution of minimally invasive approaches for TDH most of which have been posterior/posterolateral. Traditional anterior approaches involve a thoracotomy or more recently, thoracoscopic techniques. The authors describe a less invasive anterior retropleural surgical approach to address central thoracic disk herniations which is less extensive than a thoracotomy and allows better anterior access than posterior or posterolateral approaches. The retropleural approach allows the use of the operative microscope with a tubular retractor in the anterior thoracic spine. MATERIAL AND METHODS 7 patients with central disc herniation who were managed with the minimally invasive lateral retropleural approach from 2007-2010 at our institution were included in the study. Surgical technique consisted of a lateral position followed by retro-pleural exposure through tubular retractor system without the need of intraoperative lung collapse. Clinical details including age, sex, clinical presentation, surgical details, complications and outcome at last follow-up were analyzed. RESULTS Patients age ranged in age from 30 to 70 years (mean: 52 years). The duration of symptoms ranged from 4 days to 3 years. All patients presented with thoracic myleopathy on physical examination. The average length of stay in the hospital was 2.6 days (range: 1-4 days). Follow-up was available for all the patients. Myelopathy was assessed by the Nurick scale. On examination, 3 of 7 patients improved by one point on the Nurick scale. No patient deteriorated after surgery. There were no complications related to the approach. CONCLUSIONS A minimally invasive retropleural approach using tubular retractor system for central thoracic disc herniation is feasible and may be a less invasive anterior alternative to a thoracotomy.

Failure of porous tantalum cervical interbody fusion devices: Two-year results from a prospective, randomized, multicenter clinical study

Objective: The objective of this study was to assess the safety and efficacy of 2 novel cervical interbody fusion devices in the treatment of single-level degenerative cervical disk disease. Both devices were fabricated from a porous tantalum material. The high overall porosity of the devices was intended to facilitate anterior cervical interbody fusion. Methods: A prospective, randomized, 3-armed, clinical study was initiated with the following treatment groups: porous tantalum ring device packed with autograft, porous tantalum block device, and iliac crest autograft control. All the patients had single-level symptomatic cervical disk disease that had failed to respond to nonoperative therapy. Clinical and radiographic data were collected preoperatively, during surgery, before hospital discharge, and at 6 weeks, 3 months, 6 months, 12 months, and 24 months postoperatively. Results: Six investigators participated in the clinical study at 6 investigational centers in the United States. Enrollment into the study was terminated after 39 patients had been accrued because of concerns over delayed fusion in the porous tantalum treatment groups. Of the 39 patients enrolled into the clinical study, 11 patients received the control treatment of iliac autograft fusion, 13 patients received the porous tantalum ring device with the center cavity packed with cancellous iliac crest autograft, and 15 patients received the porous tantalum block device. These patients were evaluated for 24 months as per the study protocol. There were no significant differences in any of the patient demographic variables collected. The mean operative times for both the ring and block device groups were slightly lower than the control treatment. Two patients in the block treatment group were determined to be nonunion between the 6- and 12-month time points and underwent additional surgery. Five patients with porous tantalum devices showed radiographic evidence of device fragmentation, and one patient in addition had radiographic evidence of erosion of the involved vertebral bodies by the device. One patient in the ring treatment group died from a myocardial infarction and kidney failure subsequent to the 12-month follow-up visit, which was unrelated to the device or the spinal fusion procedure. Fusion rate at 2 years for the tantalum device was very low as compared with the control arm (44% vs. 100%). Patient Neck Disability Index scores, Short Form-36 scores, and neurological status scores were similar between the 3 treatment groups. Conclusions: This study demonstrates that stand-alone porous tantalum material is not ideal for a cervical spine interbody fusion because of the low rate of arthrodesis and the risk of device fragmentation in patients who fail to fuse.

Outcome following surgery for ophthalmic segment aneurysms

Ophthalmic segment aneurysms account for about 5% of all intracranial aneurysms. Anatomical complexity of the paraclinoid region makes surgical management of aneurysms arising from the ophthalmic segment challenging. This study was carried out to assess the presenting features, complications and outcomes after surgical treatment of ophthalmic segment aneurysms. The authors retrospectively analysed the clinical records of patients with ophthalmic aneurysms treated at our Institute from January 2001 to September 2008, which constituted about 9% (78/850) of all intracranial aneurysms. Of the 78 ophthalmic segment aneurysms, six patients (8%) had giant aneurysms and 19 (24%) patients had multiple aneurysms. Fifty-six patients underwent microsurgery, with direct clipping in most. The mean age was 42 years (range 12-75 years) and the mean follow-up was 8 months (range, 2-93 months). A good outcome was achieved in 46 (83%) patients (Glasgow Outcome Scale [GOS] score 4-5) and 17% had a poor outcome (GOS score 1-3) at last follow-up. The overall complication rate was 21% (12/56), most of which were transient complications, with 3.5% (2/56) mortality. Direct microsurgical clipping remains our preferred treatment approach, whenever possible, for ophthalmic segment aneurysms. This surgery has an acceptable complication rate and leads to a good outcome in more than 80% of patients with ophthalmic aneurysms. Use of modern microsurgical instrumentation and endovascular adjuncts can further reduce the surgical morbidity associated with these vascular lesions.

Clinical experience using polyetheretherketone (PEEK) intervertebral structural cage for anterior cervical corpectomy and fusion

Anterior cervical corpectomy and fusion (ACCF) is commonly performed for various pathologies involving the cervical spine. Although polyetheretherketone (PEEK) cages have been widely used following anterior cervical discectomy and fusion (ACDF), clinical literature demonstrating its efficacy following ACCF is sparse. A retrospective review of patients enrolled in a prospective database who underwent single/multi-level ACCF was performed. Fifty-nine patients were identified who underwent corpectomy reconstruction with PEEK cages for symptomatic degenerative, neoplastic, infectious, or traumatic pathologies of the cervical spine. Thirty-five patients having at least 6 months follow-up (FU) were included in the final analysis. The mean age of patients was 51 years (range, 18-81 years) with FU ranging from 6 to 33 months (mean, 6.6 months). None of the patients had dysphagia at last FU. There was no implant failure with fusion occurring in all patients. While 57% of patients (20/35) remained stable with no progression of myelopathy, 43% (15/35) improved one (11 patients) or two (four patients) Nurick grades after surgery. The use of PEEK cages packed with autograft or allograft is safe and effective following anterior cervical corpectomy, demonstrating high fusion rates and good clinical results. This synthetic material obviates the morbidity associated with autograft harvest and possible infectious risks of allograft. The wide array of cage dimensions facilitates ease of use in patients of all sizes and appears safe for use in the typical pathologic conditions encountered in the cervical spine.

Frequency, risk factors, and treatment of distal adjacent segment pathology after long thoracolumbar fusion: a systematic review.

Study Design. Systematic review. Objective. To systematically review the literature related to distal adjacent segment pathology (ASP) after long thoracolumbar fusions for deformity including frequency, risk factors, frequency differences between adolescents and adults, surgical approach for revision, and revision complications. Summary of Background Data. Spinal deformity surgery complications include ASP. Although ASP at the rostral end of instrumented fusions has been well described, substantially less has been documented about distal ASP. Methods. A systematic search was conducted in Medline and the Cochrane Collaboration Library for articles published between January 1, 1983, and March 15, 2012. We included all articles that described distal ASP after long thoracolumbar fusion for deformity. Radiographical ASP (RASP) was defined as evidence of ASP based on imaging, and clinical ASP (CASP) was defined as symptomatic ASP. Results. Seven retrospective cohort studies met inclusion criteria. Distal CASP developed in 17.7% at 2- 6-year follow-up and 19.8% at 9-year follow-up, whereas reoperation due to CASP was reported in 15.6% at 2 to 6 years and 14.4% at 9 years. Distal RASP was more frequent (44.7%–65.5%). Preoperative sagittal imbalance was associated with increased risk of distal ASP. There was increased risk of CASP in patients with higher postoperative fractional curve and increased risk of RASP in younger patients and those with preoperative disc degeneration, longer fusions, circumferential procedures, and postoperative L5–S1 disc space narrowing. No studies meeting inclusion criteria compared distal ASP in adults and adolescents or defined the best approach or complications for distal ASP revision. Conclusion. Low-quality evidence suggests a cumulative rate of 18% to 20% for CASP and 45% to 65% for RASP after long thoracolumbar fusion for spinal deformity during 9-year follow-up. Low-quality evidence suggests an association between preoperative sagittal imbalance and distal ASP, with greater risk of distal ASP in patients with sagittal imbalance. Low-quality evidence suggests increased risk of CASP in patients with higher postoperative fractional curve and increased risk of RASP in younger patients and those with preoperative disc degeneration, longer fusions, circumferential procedures, and postoperative L5–S1 disc space narrowing. Consensus StatementThe risk of developing new symptoms secondary to distal adjacent segment pathology following long thoracolumbar fusion for deformity is approximately 18–20% during a period of 9 years follow up, and most of these patients will require revision surgery.Strength of Statement: WeakThe risk of developing distal adjacent segment pathology may be higher in those with preoperative sagittal imbalance, preoperative disc degeneration, longer fusions, circumferential procedures, and postoperative L5–S1 disc space narrowing.Strength of Statement: Weak

Lateral extradural, supratentorial neurenteric cyst

Neurenteric cysts are rare congenital, benign, endodermal lesions of the central nervous system that occur mainly in the spinal canal. Intracranial neurenteric cysts are rare; the posterior fossa being the most common site. A laterally based supratentorial neurenteric cyst is exceptionally uncommon. The rarity of supratentorial neurenteric cysts and their variable imaging features preclude preoperative diagnosis. A search of the literature revealed no other extradural supratentorial neurenteric cyst. We present a patient with an extradural giant neurenteric cyst that occupied both the supratentorial and infratentorial compartments, further highlighting the heterogeneity of this rare intracranial lesion and emphasizing the need to consider this in the differential diagnosis of cystic intracranial brain lesions.

Spontaneous Thrombosis of Giant Cavernous Internal Carotid Artery Aneurysm in a Neonate

Neonatal intracranial aneurysms are rare, with only 20cases being reported in the literature. No case of spontaneous resolution of a giant intracranial cavernous segment aneurysm in a neonate is reported till date. The authors describe a 3-week-old male child who presented with a left-sided tonic seizure episode and was diagnosed as having a right-sided giant cavernous internal carotid artery aneurysm. The aneurysm was found to be totally thrombosed on angiography done before planning definitive treatment. The child is doing well at 2 years of follow-up. Spontaneous thrombosis, an exceptionally rare but fortunate outcome in a rare case of giant neonatal internal carotid artery aneurysm, has led the authors to report this case. The need of repeat imaging or angiography should be considered to rule out this rare outcome, more so if there is any delay between the ictus and treatment.