Abhaya V. Kulkarni
Babatunde J. Akinpelu, Scott L. Zuckerman, Stephen R. Gannon, Ashly Westrick, Chevis Shannon and Robert P. Naftel
Isolated transverse and spinous process fractures (TPFx and SPFx) in the thoracic and/or lumbar region have been deemed clinically insignificant in the adult population. This same rule is often applied to the pediatric population; however, little evidence exists in this younger group. The goal of this study was to describe the clinical, radiographic, and long-term data on isolated TPFx and SPFx in an exclusively pediatric population.
A retrospective chart review at Monroe Carell Jr. Children's Hospital at Vanderbilt University identified 82 pediatric patients with isolated TPFx and/or SPFx following a traumatic event between January 2000 and December 2013. Patient demographic information, presenting symptoms, radiographic characteristics, and follow-up data were collected. Follow-up was used to determine the outcome (presence of neurological deficits) of such injuries via complete physical examination and, when available, radiographic evidence.
In the 82 identified patients, the mean age was 15.5 ± 3.1 years (mean is expressed ± SD throughout), with 72 injuries (87.8%) resulting from a motor vehicle, motorcycle, or all-terrain vehicle accident. There was a mean of 1.7 ± 1.0 fractured vertebral levels involved and a mean of 1.8 ± 1.1 fractures was identified per patient. Seventy-one patients (86.6%) needed bedside pain control, 7 (8.5%) were prescribed a brace, and 4 patients (4.9%) received a collar. Physical therapy was recommended for 12 patients (14.6%). A total of 84.1% had follow-up, and the mean length of follow-up was 19 ± 37 months. No patients had true neurological deficits at presentation or follow-up as a result of their isolated fractures, whereas 95.1% had other associated system injuries.
These data shows that there is no appreciable long-term complication associated with isolated thoracic and/or lumbar TPFx and/or SPFx in an exclusively pediatric population. Because these fractures are, however, associated with high-energy blunt trauma, they often result in associated soft-tissue or other skeletal injury. All pediatric patients in the cohort benefited from conservative management and aggressive treatment of their comorbidities.
Paul M. Foreman, Robert P. Naftel, Thomas A. Moore II and Mark N. Hadley
Since its introduction in 1976, the lateral extracavitary approach (LECA) has been used to access ventral and ventrolateral pathology affecting the thoracolumbar spine. Reporting of outcomes and complications has been inconsistent. A case series and systematic review are presented to summarize the available data.
A retrospective review of medical records was performed, which identified 65 consecutive patients who underwent LECA for the treatment of thoracolumbar spine and spinal cord pathology. Cases were divided according to the presenting pathology. Neurological outcomes and complications were detailed. In addition, a systematic review of outcomes and complications in patients treated with the LECA as reported in the literature was completed.
Sixty-five patients underwent the LECA to the spine for the treatment of thoracic spine and spinal cord pathology. The most common indication for surgery was thoracic disc herniation (23/65, 35.4%). Neurological outcomes were excellent: 69.2% improved, 29.2% experienced no change, and 1.5% were worse. Two patients (3.1%) experienced a complication. The systematic review revealed comparable neurological outcomes (74.9% improved) but a notably higher complication rate (32.2%).
The LECA provides dorsal and unilateral ventrolateral access to and exposure of the thoracolumbar spine and spinal cord while allowing for posterior instrumentation through the same incision. Although excellent neurological results can be expected, the risk of pulmonary complications should be considered.
Lucy He, Stephen Gannon, Chevis N. Shannon, Brandon G. Rocque, Jay Riva-Cambrin and Robert P. Naftel
The success of endoscopic third ventriculostomy with choroid plexus cauterization may have associations with age, etiology of hydrocephalus, previous shunting, cisternal scarring, and possibly aqueduct patency. This study aimed to measure interrater reliability among surgeons in identifying cisternal scarring and aqueduct patency.
Using published definitions of cistern scarring and aqueduct patency, 7 neuroendoscopists with training from Dr. Warf in Uganda and 7 neuroendoscopists who were not trained by Dr. Warf rated cistern status from 30 operative videos and aqueduct patency from 26 operative videos. Interrater agreement was calculated using Fleiss' kappa coefficient (κ). Fisher's 2-tailed exact test was used to identify differences in the rates of agreement between the Warf-trained and nontrained groups compared with Dr. Warf's reference answer.
Aqueduct status, among all raters, showed substantial agreement with κ = 0.663 (confidence interval [CI] 0.626–0.701); within the trained group and nontrained groups, there was substantial agreement with κ = 0.677 (CI 0.593–0.761) and κ = 0.631 (CI 0.547–0.715), respectively. The identification of cistern scarring was less reliable, with moderate agreement among all raters with κ = 0.536 (CI 0.501–0.571); within the trained group and nontrained groups, there was moderate agreement with κ = 0.555 (CI 0.477–0.633) and κ = 0.542 (CI 0.464–0.620), respectively. There was no statistically significant difference in the amount of agreement between groups compared with Dr. Warf's reference.
Regardless of training with Dr. Warf, all neuroendoscopists could identify scarred cisterns and aqueduct patency with similar reliability, emphasizing the strength of the published definitions. This makes the identification of this risk factor for failure generalizable for surgical decision making and research studies.
Robert P. Naftel, R. Shane Tubbs, Gavin T. Reed and John C. Wellons III
The authors describe a new technique that may be used in conjunction with neuronavigation or freehand techniques for obtaining small ventricular access. Using this modification, the introducer sheath and trocar can be guided down a ventriculostomy tract with endoscopic visual control. With increasing focus on endoscopic therapies in patients without hydrocephalus, this adjunct, based on the authors' experience, may provide an additional technique for safely treating patients.
R. Shane Tubbs, Robert P. Naftel, William C. Rice, Peter Liechty, Michael Conklin and W. Jerry Oakes
The angulation of the sacrum is easily measured. The authors have previously reported on patients who were symptomatic with a diagnosis of myelomeningocele who were found to have changes in their lumbosacral angle (LSA) corresponding to the onset of symptoms indicative of a tethered spinal cord. The aim of this study was to verify this same finding in a group of patients with occult spinal dysraphism (that is, closed neural tube defect).
A retrospective analysis of 50 consecutive lipomyelomeningocele repair procedures was performed. Data pertaining to 30 age-matched control patients were also analyzed. Measurements were made of the LSA over time in all studied patients harboring lipomyelomeningoceles.
Appropriate imaging was available for 25 cases of lipomyelomeningocele (that is, radiographs of the lumbosacral junction were available from the patient’s perinatal period and at presentation of symptoms of a tethered spinal cord). Roughly one third of these patients suffered symptoms from a tethered spinal cord at the most recent follow-up examination. Nine patients (36%) were found to have corresponding LSA measurements greater than 70°, and seven (28%) of these patients presented with signs and symptoms of a tethered spinal cord, such as decreased lower-extremity function (two patients), urinary bladder incontinence (three patients), back pain (one patient), and lower-extremity paresthesias (one patient). The LSA measurements were statistically greater (p < 0.05) in the symptomatic patient population than in age-matched control patients and asymptomatic patients. Changes in the LSA in these symptomatic patients ranged from 5 to 24° (mean 13°). Changes in the LSA were noted in only two asymptomatic patients. No single sign or symptom of a tethered spinal cord appeared to correlate to any degree of increase in the LSA. Of the 25 patients excluded from this study because perinatal radiographic images were not available, none was symptomatic at the most recent follow-up examination and none had a grossly exaggerated LSA.
Signs and symptoms indicative of a tethered spinal cord appear to correspond to increases in the LSA. Although the authors do not advocate the use of LSA measurement as the sole indicator of a tethered spinal cord, this imaging finding may prove useful to the clinician as an indication of the tethered spinal cord or as an adjunct in verifying symptomatology in patients harboring a lipomyelomeningocele.
Robert P. Naftel, Gavin T. Reed, Abhaya V. Kulkarni and John C. Wellons III
Endoscopic third ventriculostomy (ETV) success is dependent on patient characteristics including age, origin of hydrocephalus, and history of shunt therapy. Using these factors, an Endoscopic Third Ventriculostomy Success Score (ETVSS) model was constructed to predict success of therapy. This study reports a single-institution experience with ETV and explores the ETVSS model validity.
A retrospective chart review identified 151 consecutive patients who underwent ETV at a pediatric hospital between August 1995 and December 2009. Of these 151, 136 patients had at least 6 months of clinical follow-up. Data concerning patient characteristics, operative characteristics, radiological findings, complications, and success of ETV were collected. The actual success rates were compared with those predicted by the ETVSS model.
The actual success rate of ETV at 6 months was 68.4% (93 of 136 patients), which compared well to the predicted ETVSS of 76.5% ± 12.5% (± SD). The C-statistic was 0.74 (95% CI 0.65–0.83), suggesting that the ability of the ETVSS to discriminate failures from successes was good. Secondary ETV was found to have a hazard ratio for failure of 4.2 (95% CI 2.4–7.2) compared with primary ETV (p < 0.001). The complication rate was 9.3% with no deaths. At the first radiological follow-up, the increased size of ventricles had a hazard ratio for failure of 3.0 (95% CI 1.5–6.0) compared with patients in whom ventricle size either remained stable or decreased (p = 0.002).
The ETVSS closely predicts the actual success of ETV, fitting the statistical model well. Shortcomings of the model were identified in overestimating success in patients with ETVSS ≤ 70, which may be attributable to the poor success of secondary ETVs in the authors' patient population.
Robert P. Naftel, Nicole A. Safiano, Michael Falola, Jeffrey P. Blount, W. Jerry Oakes and John C. Wellons III
Children experiencing frequent shunt failure consume medical resources and represent a disproportionate level of morbidity in hydrocephalus care. While biological causes of frequent shunt failure may exist, this study analyzed demographic and socioeconomic patient characteristics associated with frequent shunt failure.
A survey of 294 caregivers of children with shunt-treated hydrocephalus provided demographic and socioeconomic characteristics. Children experiencing at least 10 shunt failures were considered frequent shunt-failure patients. Multivariate regression models were used to control for variables.
Frequent shunt failure was experienced by 9.5% of the patients (28 of 294). By univariate analysis, white race (p = 0.006), etiology of hydrocephalus (p = 0.022), years-with-shunt (p < 0.0001), and surgeon (p = 0.02) were associated with frequent shunt failure. Upon multivariate analysis, white race remained the key independent factor associated with frequent shunt failure (OR 5.8, 95% CI 1.2–27.8, p = 0.027). Race acted independently from socioeconomic factors, including income, level of education, and geographic location, and clinical factors, such as etiology of hydrocephalus, surgeon, and years-with-shunt. Additionally, after multivariate analysis surgeon and years-with-shunt remained associated with frequent shunt failure (p = 0.043 and p = 0.0098, respectively), although etiology of hydrocephalus was no longer associated (p = 0.1).
White race was the primary independent factor associated with frequent shunt failure. Because races use health care differently and the diagnosis of shunt failure is often subjective, a disparity in diagnosis and treatment has arisen. These findings call for objective criteria for the preoperative and intraoperative diagnosis of shunt failure.
Report of 4 cases
Joshua J. Chern, Amber S. Gordon, Robert P. Naftel, R. Shane Tubbs, W. Jerry Oakes and John C. Wellons III
Intracranial endoscopy in the treatment of hydrocephalus, arachnoid cysts, or brain tumors has gained wide acceptance, but the use of endoscopy for intradural navigation in the pediatric spine has received much less attention. The aim of the authors' present study was to analyze their experience in using spinal endoscopy to treat various pathologies of the spinal canal.
The authors performed a retrospective review of intradural spinal endoscopic cases at their institution. They describe 4 representative cases, including an arachnoid cyst, intrinsic spinal cord tumor, holocord syrinx, and split cord malformation.
Intradural spinal endoscopy was useful in treating the aforementioned lesions. It resulted in a more limited laminectomy and myelotomy, and it assisted in identifying a residual spinal cord tumor. It was also useful in the fenestration of a multilevel arachnoid cyst and in confirming communication of fluid spaces in the setting of a complex holocord syrinx. Endoscopy aided in the visualization of the spinal cord to ensure the absence of tethering in the case of a long-length Type II split spinal cord malformation.
Based on their experience, the authors found intradural endoscopy to be a useful surgical adjunct and one that helped to decrease morbidity through reduced laminectomy and myelotomy. With advances in technology, the authors believe that intradural endoscopy will begin to be used by more neurosurgeons for treating diseases of this anatomical region.