Apolipoprotein E and myelopathy
Hong-liang Zhang, Ping Liu and Shuai Yan
Markus Bruder, Adriano Cattani, Florian Gessler, Christian Droste, Matthias Setzer, Volker Seifert and Gerhard Marquardt
Synovial cysts of the spine are rare lesions, predominantly arising in the lumbar region. Despite their generally benign behavior, they can cause severe symptoms due to compression of neural structures in the spinal canal. Treatment strategies are still a matter of discussion. The authors performed a single-center survey and literature search focusing on long-term results after minimally invasive surgery.
A total of 141 consecutive patients treated for synovial cysts of the lumbar spine between 1997 and 2014 in the authors’ department were analyzed. Medical reports with regard to signs and symptoms, operative findings, complications, and short-term outcome were reviewed. Assessment of long-term outcome was performed with a standardized telephone questionnaire based on the Oswestry Disability Index (ODI). Furthermore, patients were questioned about persisting pain, symptoms, and further operative procedures, if any. Subjective satisfaction was classified as excellent, good, fair, or poor based on the Macnab classification.
The approach most often used for synovial cyst treatment was partial hemilaminectomy in 70%; hemilaminectomy was necessary in 27%. At short-term follow-up, the presence of severe and moderate leg pain had decreased from 93% to 5%. The presence of low-back pain decreased from 90% to 5%. Rates of motor and sensory deficits were reduced from 40% to 14% and from 45% to 6%, respectively. The follow-up rate was 58%, and the mean follow-up period was 9.3 years. Both leg pain and low-back pain were still absent in 78%. Outcome based on the Macnab classification was excellent in 80%, good in 14%, fair in 1%, and poor in 5%. According to the ODI, 78% of patients had no or only minimal disability, 16% had moderate disability, and 6% had severe disability at the time of follow-up. In this cohort, 7% needed surgery due to cyst recurrence, and 9% required a delayed stabilization procedure after the initial operation.
Surgical treatment with resection of the cyst provides favorable results in outcome. Excellent or good outcome persisting for a long-term follow-up period can be achieved in the vast majority of cases. Complication rates are low despite an increased risk of dural injury. With facet-sparing techniques, the stability of the segment can be preserved, and resection of spinal synovial cysts does not necessarily require segmental fusion.
Surbhi Jain, Eric Sommers, Matthias Setzer and Frank Vrionis
The treatment of Pancoast (superior sulcus) tumors that extensively invade the vertebral column remains controversial. Different surgical approaches involving multistage resection techniques have been previously described for superior sulcus tumors that invade the chest wall and spinal column. Typically a posterior approach to stabilize the spine is followed by a second-stage thoracotomy (posterolateral or trap door) for definitive en bloc resection of stage T4 Pancoast tumors. The authors report and elaborate on a surgical technique successfully used for an en bloc resection as well as spinal stabilization through a single-stage posterior approach without any added morbidity.
Two patients with histologically proven Pancoast tumors were treated by single-stage resection and stabilization through a posterior approach at the H. Lee Moffitt Cancer Center. A wedge lung resection or lobectomy was performed by the chest surgeon utilizing the chest wall defect. Placement of an anterior cage (in one case) and posterior cervicothoracic spinal instrumentation (in both cases) was performed during the same operation. Average blood loss was 675 ml and surgical time was 7 hours. The median hospital stay was 9 days (range 7–11 days). Both patients did well postoperatively and were free of recurrence at the 2-year follow-up.
Radical resection of Pancoast tumors including lobectomy, chest wall resection, costotransversectomy, and partial or complete vertebrectomy with simultaneous instrumentation for spinal stabilization can be performed through a posterior single-stage approach.
Matthias Setzer, Hartmut Vatter, Gerhard Marquardt, Volker Seifert and Frank D. Vrionis
In this report, the authors describe their experience in the surgical management of spinal meningiomas at two neurosurgical centers. The results of a literature review are also presented.
Eighty consecutive patients (22 men and 58 women) with spinal meningiomas who had undergone an operation at two specific neurosurgical centers were included in this study. Functional outcomes were evaluated using univariate and multivariate analyses. A review of the literature yielded an additional 651 patients with spinal meningiomas from 9 large studies.
On multivariate analysis, the variable of a poor preoperative neurological state (p < 0.02, odds ratio [OR] 13.6, 95% confidence interval [CI] 2.6–71.4) and invasion of the arachnoid/pia mater (p < 0.03, OR 15.2, 95% CI 2.5–90.4) were independent predictors of a poor outcome, whereas invasion of the arachnoid/pia (p < 0.02, OR 8.9, 95% CI 2.2–35) and duration of symptoms (p < 0.001, OR 1.12/month, 95% CI 1.05–1.2) predicted no improvement (stable or deteriorated condition). The Cox proportional hazards regression analysis showed three significant predictor variables for recurrence: invasion of the arachnoid/pia (p < 0.05; hazard ratio [HR] 1.8, 95% CI 1.2–3.6), Simpson resection grade (p < 0.012, HR 6.8, 95% CI 1.5–3.0), and histological tumor grade (Grade I; p < 0.001, HR 0.001–0.17).
Because of the excellent outcome of surgery for benign spinal meningiomas and the association between duration of symptoms and neurological compromise with a poor functional outcome, early operation is the treatment of choice. In cases of malignant transformation, adjuvant therapies must be considered.
Gerhard Marquardt, Matthias Setzer, Alf Theisen, Edgar Dettmann and Volker Seifert
Object. The goal of this study was to develop a novel dynamic model for experimental spinal cord compression that closely approximates neoplastic epidural compression of the spinal cord in humans.
Methods. In 30 New Zealand white rabbits, the thoracic spine was exposed via a posterior approach. On each side of one vertebral lamina a small hole was drilled caudal to the articular process. A silicone band was passed through these holes, forming a loop. The spinal dura mater was exposed via an interlaminar approach. The loop was brought into contact with the dura mater and fixed in its position encircling 270° of the circumference of the spinal cord. Thereafter, the loop was gradually tightened at set times by pulling at the ends of the band and fixing them again in their new position. The spinal cord was thus increasingly compressed in a circular and dynamic manner.
Neurological deficits of various degrees were created in all animals in the compression group, and the compressive effect of the loop was reliably demonstrated on MR imaging. After decompression of the spinal cord, the neurological deficits were reversible in the majority of animals, and MR imaging revealed either no signal changes or only circumscribed ones within the cord. In contrast, MR images obtained in animals that did not recover revealed the occurrence of extensive chronic myelopathy.
Conclusions. This novel model features reproducibility of paresis and neurological recovery. It is a dynamic model simulating circular tumor growth and is characterized by its easy, straightforward, and cost-saving applicability.
Matthias Setzer, Frank D. Vrionis, Elvis J. Hermann, Volker Seifert and Gerhard Marquardt
The authors examined a possible association between apolipoprotein E (APOE) gene polymorphism and the outcome after anterior microsurgical decompression in patients with cervical spondylotic myelopathy (CSM).
The authors conducted a prospective study of 60 consecutive patients (40 men, 20 women) with CSM who underwent anterior microsurgical decompression. The patients ranged in age from 26 to 86 years (mean 61.5 ± 14.6 years). Neurological deficits were classified according to the modified Japanese Orthopaedic Association Scale. Mean follow-up was 18.8 ± 4.6 months and APOE genotyping was carried out by isolation of DNA from venous blood samples. The APOE genotypes were determined by polymerase chain reaction followed by restriction enzyme digestion and polyacrylamide gel electrophoresis of digested fragments. Categorical variables were analyzed with the chi-square test, continuous data with the Mann-Whitney U-test, and for multiple groups with the Kruskal-Wallis H-test. A backward stepwise binary logistic regression analysis was performed to determine the effect of APOE in a multivariate model.
Of the 60 patients with CSM, 35 (58.3%) improved and 25 (41.7%) did not improve or suffered deterioration (no-improvement group). In the improvement group 5 patients (8.3%) possessed the ε4 allele compared with 16 patients (26.7%) in the no-improvement group (p = 0.002, OR 3.3, 95% CI 1.7–6.1). In a multivariate model, the occurrence of the ε4 allele was a significant independent predictor for no improvement after anterior decompression and fusion (p = 0.004, OR 8.6, 95% CI 5.1–20.6).
The results of this study show that APOE gene polymorphism influences the short-term outcome of CSM patients after surgical decompressive and stabilizing therapy in the way that the presence of the APOE ε4 allele is an independent predictor for a no improvement. The presence of APOE may explain in part the different responses to operative therapies in patients with cervical myelopathy.
Florian Gessler, Haitham Mutlak, Karima Tizi, Christian Senft, Matthias Setzer, Volker Seifert and Lutz Weise
The value of postoperative epidural analgesia after major spinal surgery is well established. Thus far, the use of patient-controlled epidural analgesia (PCEA) has been denied to patients undergoing debridement and instrumentation in spondylodiscitis, with the risk of increased postoperative pain resulting in prolonged recovery. The value of PCEA with special regard to infectious complications remains to be clarified. The present study examined the value of postoperative PCEA in comparison with intravenous analgesia in patients with spondylodiscitis undergoing posterior spinal surgery.
Thirty-two patients treated surgically for spondylodiscitis of the thoracic and lumbar spine were prospectively included in a database and retrospectively reviewed for this study. Postoperative antibiotic treatment, functional capacity, pain levels, side effects, and complications were documented. Sixteen patients were given patient-demanded intravenous analgesia (PIA) followed by 16 patients assigned to PCEA. If PCEA was applied, the insertion of an epidural catheter was performed under the direct visual guidance of the surgeon at the end of the surgery.
Three patients intended for PCEA treatment were excluded due to predefined exclusion criteria. Postoperative pain was significantly lower in the PCEA group during the first 48 hours after surgery (p = 0.03). As determined by the trunk control test conducted at 8 (p < 0.001), 24 (p = 0.004), 48 (p = 0.015), 72 (p = 0.0031), and 96 hours (p < 0.001), patients in the PCEA treatment group displayed significantly increased mobilization capacity compared with those of the PIA group. Time until normal accomplishment of all mobilization maneuvers was reduced in the PCEA group compared with that in the PIA group (p = 0.04). No differences in complication rates were observed between the 2 groups (p = 0.52).
PCEA may reduce postoperative pain and lead to earlier achievement of functional capacity at a low complication rate in patients with surgically treated lumbar and thoracic spondylodiscitis.
Matthias Setzer, Mohamed Eleraky, Wesley M. Johnson, Kamran Aghayev, Nam D. Tran and Frank D. Vrionis
The objective of this study was to compare the stiffness and range of motion (ROM) of 4 cervical spine constructs and the intact condition. The 4 constructs consisted of 3-level anterior cervical discectomy with anterior plating, 1-level discectomy and 1-level corpectomy with anterior plating, 2-level corpectomy with anterior plating, and 2-level corpectomy with anterior plating and posterior fixation.
Eight human cadaveric fresh-frozen cervical spines from C2–T2 were used. Three-dimensional motion analysis with an optical tracking device was used to determine motion following various reconstruction methods. The specimens were tested in the following conditions: 1) intact; 2) segmental construct with discectomies at C4–5, C5–6, and C6–7, with polyetheretherketone (PEEK) interbody cage and anterior plate; 3) segmental construct with discectomy at C6–7 and corpectomy of C-5, with PEEK interbody graft at the discectomy level and a titanium cage at the corpectomy level; 4) corpectomy at C-5 and C-6, with titanium cage and an anterior cervical plate; and 5) corpectomy at C-5 and C-6, with titanium cage and an anterior cervical plate, and posterior lateral mass screw-rod system from C-4 to C-7. All specimens underwent a pure moment application of 2 Nm with regards to flexion-extension, lateral bending, and axial rotation.
In all tested motions the statistical comparison was significant between the intact condition and the 2-level corpectomy with anterior plating and posterior fixation construct. All other statistical comparisons between the instrumented constructs were not statistically significant except between the 3-level discectomy with anterior plating and the 2-level corpectomy with anterior plating in axial rotation. There were no statistically significant differences between the 1-level discectomy and 1-level corpectomy with anterior plating and the 2-level corpectomy with anterior plating in any tested motion. There was also no statistical significance between the 3-level discectomy with anterior plating and the 2-level corpectomy with anterior plating and posterior fixation.
This study demonstrates that segmental plate fixation (3-level discectomy) affords the same stiffness and ROM as circumferential fusion in 2-level cervical spine corpectomy in the immediate postoperative setting. This obviates the need for staged circumferential procedures for multilevel cervical spondylotic myelopathy. Given that the posterior segmental instrumentation confers significant stability to a multilevel cervical corpectomy, the surgeon should strongly consider the placement of segmental posterior instrumentation to significantly improve the overall stability of the fusion construct after a 2-level cervical corpectomy.
Bedjan Behmanesh, Matthias Setzer, Anika Noack, Marco Bartels, Johanna Quick-Weller, Volker Seifert and Thomas M. Freiman
Monitoring of intracranial pressure (ICP) may be indicated in children with traumatic brain injury, premature intraventricular hemorrhage, or hydrocephalus. The standard technique is either a direct measurement with invasive intracranial insertion of ICP probes or indirect noninvasive assessment using transfontanelle ultrasonography to measure blood flow. The authors have developed a new technique that allows noninvasive epicutaneous transfontanelle ICP measurement with standard ICP probes. They compared the ICP measurements obtained using the same type of standard probe used in 2 different ways in 5 infants (age < 1 year) undergoing surgery for craniosynostosis. The first ICP probe was implanted epidurally (providing control measurements) and the second probe was fixed epicutaneously on the skin over the reopened frontal fontanelle. ICP values were measured hourly for the first 24 hours after surgery and the values obtained with the 2 methods were compared using Bland-Altman 2-methods analysis.
A total of 110 pairs of measurements were assessed. There was no significant difference between the ICPs measured using the epicutaneous transfontanelle method (mean 13.10 mm Hg, SEM 6.68 mm Hg) and the epidural measurements (mean 12.46 mm Hg, SEM 6.45 mm Hg; p = 0.4643). The results of this analysis indicate that epicutaneous transfontanelle measurement of ICP is a reliable method that allows noninvasive ICP monitoring in children under the age of 1 year. Such noninvasive ICP monitoring could be implemented in the therapy of children with traumatic brain injury or intraventricular hemorrhage or for screening children with elevated ICP without invasive intracranial implantation of ICP probes.
Michael Kern, Matthias Setzer, Lutz Weise, Ali Mroe, Holger Frey, Katharina Frey, Volker Seifert and Stephan Duetzmann
The treatment of patients with spinal stenosis and concurrent degenerative spondylolisthesis is controversial. Two large randomized controlled clinical trials reported contradictory results. The authors hypothesized that a substantial number of patients will show evidence of micro-instability after a sole decompression procedure.
This study was a retrospective analysis of all cases of lumbar spinal stenosis treated at the Frankfurt University Clinic (Universitätsklinik Frankfurt) from 2010 through 2013. Patients who had associated spondylolisthesis underwent upright MRI studies in flexion and extension for identification of subtle signs of micro-instability. Clinical outcome was assessed by means of SF-36 bodily pain (BP) and physical functioning (PF) scales.
A total of 21 patients were recruited to undergo upright MRI studies. The mean duration of follow-up was 65 months (SD 16 months). Of these 21 patients, 10 (47%) showed signs of micro-instability as defined by movement of > 4 mm on flexion/extension MRI. Comparison of mean SF-36 BP and PF scores in the group of patients who showed micro-instability versus those who did not showed no statistically significant difference on either scale.
There seems to be a substantial subset of patients who develop morphological micro-instability after sole decompression procedures but do not experience any clinically significant effect of the instability.