Assessment of adjacent-segment mobility after cervical disc replacement versus fusion: RCT with 1 year's results.

Disc prostheses have been designed to restore and maintain cervical segmental motion and reduce the accelerated degeneration of the adjacent level. There is no knowledge about the reaction of the neighboured asymptomatic segments after implantation of prostheses or fusion. The effects of these procedures to segmental movement of the uninvolved vertebrae have not been subjected to studies so far. The objective of this study was to compare the segmental motion following cervical disc replacement versus fusion and the correlation to the clinical outcome. Another aim was to compare the segmental motion of the asymptomatic segments above the treated ones and to compare both with Roentgen stereometric analysis (RSA) including the asymptomatic segments. 20 patients with one-level cervical radiculopathy scheduled for surgery were randomized to arthroplasty (10 patients, study group) or anterior cervical discectomy and fusion (10 patients, control group). Clinical results were evaluated using Visual Analogue Scale and Neck Disability Index. RSA was performed immediately postoperative, after 6 and 12 months. The adjacent segment showed a significantly higher segmental motion in all three-dimensional axes in comparison to the segment treated with prostheses (P < 0.05). In the fusion group the segmental motion of the adjacent segment was significantly higher in all three-dimensional axes (P < 0.05) at each examination time. When the adjacent level of both groups is compared, the fusion group could show a higher segmental motion in all three-dimensional axes, but without significant difference (P > 0.05) 1 year after surgery. Regarding the clinical results, there was no significant difference in pain relief between both groups (P > 0.05). In conclusion, the adjacent segment could show a higher segmental motion, when compared with the segment either treated with prostheses or fusion. There was no significant difference in segmental motion adjacent to prosthesis or fusion. Clinical results did also show no significant difference in pain relief between both groups.

Increased intracranial pressure caused by non-space-occupying arachnoid cysts: report of two patients.

In this article we report on two patients with arachnoid cysts previously treated by shunt implantation presenting with clinical signs of an increased intracranial pressure i. e., papilledema, headache and nausea. Repeated MRI scans showed no alteration of the cerebrospinal fluid circulation and no space-occupying effect of the cysts. Although neuroimaging showed no signs of increased intracranial pressure, neurosurgical exploration was performed and revealed a distinctly increased pressure in both arachnoid cysts. After replacement of the shunt a prompt reduction of papilledema and relief of symptoms was observed.

Infection rate with application of an antibiotic-impregnated catheter for shunt implantation in children - a retrospective analysis.

BACKGROUND: The infection rate of hydrocephalus shunts in children amounts figures of up to 25% and the according mortality rate is alarming high nowadays yet. An antibiotic impregnated shunt-catheter (AIS) was designed to reduce the incidence of shunt infections. PATIENTS AND METHOD: In a non randomized trial 56 children were examined between January 2002 inclusive December 2007. The minimal follow-up was six months. Only children were included, who were shunted for the first time. In the study group (n=34) AIS (Bactiseal ) Codman, Johnson & Johnson, MA, Boston, USA) were used, while the control group (n=22) was provided with conventional, not-antibiotic impregnated catheters. To compare the risk profile for shunt infections, we defined, - according to the literature -, some risk factors. RESULTS: Despite the incidence of shunt infections has been supposed to be higher according to the higher risk profile of the AIS group compared with controls, the shunt infection rate of the AIS group was lower than the shunt infection rate in the control group. CONCLUSIONS: Apparently, AIS can reduce the incidence of shunt infections in children. Further prospective trials with a larger cohort are necessary for a statistically significant prove.

Combining gene expression signatures and autoantibody profiles in human meningioma.

Gene expression profiling has emerged as powerful technique for studying the mechanisms of tumor genesis and development. Seroreactivity profiling of tumor antigens is a more recent technique that further contributes to the understanding of tumors and that offers itself for noninvasive tumor diagnosis. We performed expression profiling of 55,000 transcripts and expressed-sequence-tags for 24 meningiomas and related these data to autoantibody profiles of more than 50 antigens immunogenic in the autologous patients. The expression values of antigens in WHO grade I meningioma were significantly higher if the patients' sera reacted with these antigens as confirmed by a two-tailed Wilcoxon-Mann-Whitney test. Specifically, KIAA1344 that was previously identified as frequent antigen marker in meningioma, showed increased expression if antigens against KIAA1344 were detected in autologous patients. Our study is the first to combine genome-wide expression signatures and comprehensive seroreactivity patterns toward a more complete view on tumor immunology, especially concerning the overall role of the level of gene expression on the immunogenicity of meningioma antigens.

Biomechanical effect of different lumbar interspinous implants on flexibility and intradiscal pressure.

Interspinous implants are used to treat lumbar spinal stenosis or facet joint arthritis. The aims of implanting interspinous devices are to unload the facet joints, restore foraminal height and provide stability especially in extension but still allow motion. The aim of this in vitro study was to compare four different interspinous implants--Colfex, Wallis, Diam and X-Stop--in terms of their three-dimensional flexibility and the intradiscal pressure. Twenty-four human lumbar spine specimens were divided into four equal groups and tested with pure moments in flexion/extension, lateral bending and axial rotation: (1) intact, (2) defect, (3) after implantation. Range of motion and the intradiscal pressure were determined. In each implant-group the defect caused an increase in range of motion by about 8% in lateral bending to 18% in axial rotation. Implantation had similar effects with all four implants. In extension, Coflex, Wallis, Diam, and X-Stop all overcompensated the instability caused by the defect and allowed about 50% of the range of motion of the intact state. In contrast, in flexion, lateral bending and axial rotation the values of the range of motion stayed about the values of the defect state. Similarly the intradiscal pressure after implantation was similar to that of the intact specimens in flexion, lateral bending and axial rotation but much smaller during extension. All tested interspinous implants had a similar effect on the flexibility: they strongly stabilized and reduced the intradiscal pressure in extension, but had almost no effect in flexion, lateral bending and axial rotation.

Cervical spondylolisthesis C6-C7 in a young wrestler: case report.

We present both the clinical and radiographic data of a 15-year-old boy, suffering from a lytic spondylolisthesis C6-C7 and treated by circumferential fusion.

Accuracy of ultrasound-guided puncture of the ventricular system.

OBJECTS: Puncture of the ventricular system as one of the most frequently performed operative procedures in neurosurgery is usually done in a freehand way without guiding devices. The objective of this study is to examine whether ultrasonic guidance is able to heighten the accuracy of ventricular tapping. METHODS: Real-time imaging via a single burr hole approach is achieved by aid of a bajonet-like shaped transducer with a footprint of 8x8 mm only (EUP-NS32, Hitachi Medical Systems). The needle is advanced towards the frontal horn along a displayed guideline. 51 punctures in 48 patients were performed with ultrasonic guidance and compared to 85 punctures in 67 patients without a guiding device. CONCLUSION: The presented ultrasound method was not able to heighten the access rate of ventricular tapping, but it improved correct positioning of the catheter tip inside the frontal horn of the ventricular system significantly.

The histochemical profile of the rat extensor digitorum longus muscle differentiates after birth and dedifferentiates in senescence.

Age dependent motor unit dedifferentiation is a key component of impaired muscle function in advanced age. Here, we tested the hypothesis that rat muscle histochemical profile during the lifespan of an individual has an age-specific pattern since comprehensive longitudinal studies of muscle differentiation after birth and dedifferentiation in advanced age are scarce. Our results show that extensor digitorum longus muscle (EDL) is comprised only of two fiber types after birth, type slow-oxidative (SO) and type SDH-intermediate (SDH-INT), the latter being indicative for the presence of polyneuronal innervation. In contrast to the constantly growing cross-sectional area of the muscle fibers, a dramatic decrease in SDH-INT proportion occurs between day 14 and 21 after birth resulting in a complete loss of fiber type SDH-INT at the age of 90 days (p<0.05). At the age of 270 days, the fiber type composition of rat EDL dedifferentiates as shown by the reappearance of the SDH-INT type with a further increase at the age of 540 days (p<0.05). These changes in histochemical fiber type spectra are brought about by fiber type conversion within the fast twich fibers. The findings of the present study provide further evidence that fiber type conversion is a basic mechanism leading to motor unit differentiation and dedifferentiation during ontogenesis. Fiber type conversion shows a distinct time specific pattern and is also characteristic for motor unit regeneration after peripheral nerve repair. Factors that influence fiber type conversion and thereby motor unit organization may provide a future therapeutic option to enhance the regenerative capacity of motor units.

Radiographic analysis of fusion progression following one-level cervical fusion with or without plate fixation.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) using bone graft or a cage with plate fixation is an accepted technique for the treatment of symptomatic degenerative disc disease. It is, however, debatable whether a plate is really necessary to increase the progress of fusion. Thus, the aim of this randomized and controlled prospective study was to evaluate whether ACDF with a cage and anterior plate fixation results in a greater progress of fusion compared with ACDF using a stand-alone cage. METHODS: 37 candidates for ACDF were treated either with a stand-alone cage (study group) or with a cage+plate fixation (control group). 19 patients were randomized to be stabilized with a stand-alone cage and 18 patients were treated with a cage and additional anterior plate fixation. The progress of cervical fusion over time was compared by radiostereometric analysis (RSA). Follow-up examinations pre- and postoperatively were done using the Visual Analogue Scale (VAS) for neck and arm pain. Radiographic assessment of fusion using an RSA-control was done after one, six and twelve weeks, as well as after six months, and one and two years postoperatively. Mann-Whitney test for unpaired values was used to determine the statistical differences in residual intervertebral motion. RESULTS: Three-dimensional analysis of segmental motion (left-right, cranio-caudal, and posterior-anterior) did not reveal any statistical differences between both groups at any examination time postoperatively ( P>0.05). The VAS score did not differ between the groups ( P>0.05). CONCLUSION: Anterior plate fixation did not demonstrate an improvement in the progress of fusion in one-level ACDF.

[Cubital tunnel syndrome--simple nerve decompression or decompression with subcutaneous anterior transposition?]. / Sulcus-ulnaris-Syndrom: Einfache Dekompression oder subkutane Vorverlagerung?

The purpose of this prospective, randomised and controlled study was to evaluate which kind of operative technique for treatment of cubital tunnel syndrome is favourable: subcutaneous anterior transposition or nerve decompression without transposition. This study included 66 patients suffering from pain and/either neurological deficits with clinically and electrographically proven cubital tunnel syndrome. 32 patients underwent nerve decompression without transposition, whereas 34 underwent subcutaneous transposition of the nerve. Follow-up examinations evaluating pain, motor and sensory deficits as well as motor nerve conduction velocities were performed three, nine and 24 months postoperatively. Irrespectively of operative procedures (simple decompression vs. subcutaneous anterior transposition) there were no significant differences between the outcomes of the two groups at either postoperative follow-up examination (p > 0.05).

Disc replacement using Pro-Disc C versus fusion: a prospective randomised and controlled radiographic and clinical study.

Anterior cervical discectomy and fusion (ACDF) may be considered to be the gold standard for treatment of symptomatic degenerative disc disease within the cervical spine. However, fusion of the segment may result in progressive degeneration of the adjacent segments. Therefore, dynamic stabilization procedures have been introduced. Among these, artificial disc replacement by disc prosthesis seems to be promising. However, to be so, segmental motion must be preserved. This, again, is very difficult to judge and has not yet been proven. The aim of the current study was to first analyse the segmental motion following artificial disc replacement using a disc prosthesis. A second aim was to compare both segmental motion as well as clinical result to the current gold standard (ACDF). This is a prospective controlled study. Twenty-five patients with cervical disc herniation were enrolled and assigned to either study group (receiving a disc prosthesis) or control group (receiving ACDF, using a cage with bone graft and an anterior plate.) Radiostereometric analysis was used to quantify intervertebral motion immediately as well as 3, 6, 12 and 24 weeks postoperatively. Further, clinical results were judged using visual analogue scale and neuro-examination. Cervical spine segmental motion decreased over time in the presence of disc prosthesis or ACDF. However, the loss of segmental motion is significantly higher in the ACDF group, when looked at 3, 6, 12 and 24 weeks after surgery. We observed significant pain reduction in neck and arm postoperatively, without significant difference between both groups (P > 0.05). Cervical spine disc prosthesis preserves cervical spine segmental motion within the first 6 months after surgery. The clinical results are the same when compared to the early results following ACDF.

Analysis of spinal kinematics following implantation of lumbar spine disc prostheses versus fusion: radiological study.

STUDY DESIGN: This is a prospective controlled study comparing lumbar spine disc replacement versus fusion for monosegmental degenerative disc disease (DDD). SUMMARY OF BACKGROUND DATA AND OBJECTIVE: Fusion has been reported to be the standard therapy by DDD of the lumbar spine. Due to unsatisfactory long-term results of fusion by progressive adjacent level degeneration, disc replacement was developed and thought to reduce pain while restoring disc height and motion at the affected level. The expected long-term advantage of disc replacement over fusion is the preservation of motion. This again is very difficult to judge; therefore the aim of the current study was to analyze segmental motion following disc replacement versus fusion. METHODS: Patients meeting inclusion criteria were consented for the study. This analysis includes data up to 12 months from the first included patients. There were 13 patients who underwent disc replacement, and 11 patients had fusion procedures. Radiostereometric analysis was done 1 and 6 weeks and 3, 6, and 12 months after surgery. RESULTS: The mobility provocation RSA showed a significant segmental motion in the disc replacement group in comparison to fusion. CONCLUSIONS: Disc replacement using Active L prostheses preserves segmental motion during the period examination time of 12 months.

Segmental kinematics and adjacent level degeneration following disc replacement versus fusion: RCT with three years of follow-up.

STUDY DESIGN: Prospective, randomized and controlled clinical and radiological study. OBJECTIVE: The aim of this study was to assess the segmental kinematics and clinical outcome of disc replacement with ProDisc C versus anterior cervical discectomy and fusion (ACDF) for monosegmental disease 3 years after surgery. SUMMARY OF BACKGROUND DATA: Anterior cervical discectomy and fusion (ACDF), including plate fixation, is an accepted technique for treatment of symptomatic degenerative disc disease (DDD). However, various studies could show that fusion of a relative mobile spinal segment leads to heightens of stresses on the discs below and above fusion, which is manifested as adjacent level degeneration. Intervertebral disc replacement has been attempted to restore intervertebral disc height and to maintain segmental motion, which may be thought to avoid the accelerated degeneration to the adjacent level. In earlier studies, we could show that ProDisc C could maintain segmental motion for 1 year after surgery. METHODS: 49 patients with cervical disc herniation underwent arthroplasty of a single level using ProDisc C disc prosthesis or received fusion using a cage and anterior titanium plate fixation. Clinical outcome was assessed using the visual analogue scale (VAS) and the neck disability index (NDI). Radiostereometry was performed immediately postoperative and then after 1, 2, and 3 years after surgery to quantify the segmental kinematics. RESULTS: The range of motion of the treated segment with prosthesis remained unchanged 3 years after surgery in comparison to the 1-year result. The prosthesis shows a significant segmental motion in contrast to the fusion group at each RSA examination time (p < 0.05). After both procedures, a significant pain reduction in neck and arm was observed, without significant differences between both groups. During the course of the 3 years follow-up, no patients of the prosthesis group required further surgical intervention.

Outcome predictors for normal-pressure hydrocephalus.

The objective of this prospective study was to find outcome predictors for better selection for treatment of normal-pressure hydrocephalus (NPH) patients. A total of 125 patients were evaluated and provided with a gravitational shunt. Cerebrospinal fluid hydrodynamics provided better predictive values if an algorithm to shunt all patients with a pressure/volume index of < 30 mL or resistance to outflow > 13 mmHg/mL x min was used. In general, outcome became worse with increasing anamnesis duration, worse preoperative clinical state, and increasing comorbidity. If one of these parameters was lower than a critical value, the shunt-responder rate was about 90% and the normally negative influence of older age was not seen. The well-known paradigm of a worse prognosis with NPH is not the result of the hydrocephalus etiology itself, but the consequence of a typical accumulation of negative outcome predictors as a consequence of the misinterpretation of normal aging and delayed adequate treatment.

Filling a cervical spine cage with local autograft: change of bone density and assessment of bony fusion.

To date, it remains debatable whether cervical spine fusion cages should be filled with any kind of bone or bone substitute. Using a bone substitute would produce additional costs, using an autologous bone graft from the iliac crest would make the use of the cage at least questionable. As an alternative, cortical and subcortical bone from the anterior osteophytes of the segment in which the disc has been removed could be used to fill the cage: higher costs and complications at the iliac crest could both be avoided and the cage could be filled. However, the fate of these bone chips made from the anterior osteophytes is unclear as well as whether fusion will occur using this technique. The objective of the current study was to investigate possible changes in the bone density of this local autograft in the cage within the first 12 months after surgery by means of computed tomography. A second objective was to assess segmental bony fusion using this technique. 21 patients, suffering from degenerative disc disease of the cervical spine, were included into this prospective study. They all underwent anterior decompression, cage insertion and plate stabilisation. The cage (Rabea, Signus Medizintechnik, Alzenau, Germany), was filled with bone chips made from the anterior osteophytes of the segment that underwent discectomy. On the third day after surgery as well as three, six and 12 months after surgery, an axial computed tomography scan through the cage was taken and density within the apertures of the cage was measured in a standardised manner. Flexion-extension lateral radiographs were taken to investigate segmental fusion. Statistical significance was assumed to be at a 95 % level of significance. 23 cages were implanted. The mean value of the bone density obtained by computed tomography was 505 (+/- 119) HU on day three, 635 (+/- 156) HU after three months, 769 (+/- 162) HU after six months, and 814 (+/- 198) after 12 months. There was a significant difference when the values after 12 months were compared to those obtained after three days (p < 0.001) and after three months (p = 0.004). Bony fusion was seen in 21 out of 23 segments (91.3 %) after 12 months. It may be concluded that this technique could be an alternative to the current treatment options.

Simple decompression or subcutaneous anterior transposition of the ulnar nerve for cubital tunnel syndrome.

The purpose of this prospective randomised study was to evaluate which operative technique for treatment of cubital tunnel syndrome is preferable: subcutaneous anterior transposition or nerve decompression without transposition. This study included 66 patients suffering from pain and/or neurological deficits with clinically and electromyographically proven cubital tunnel syndrome. Thirty-two patients underwent nerve decompression without transposition and 34 underwent subcutaneous transposition of the nerve. Follow-up examinations evaluating pain, motor and sensory deficits as well as motor nerve conduction velocities, were performed 3 and 9 months postoperatively. There were no significant differences between the outcomes of the two groups at either postoperative follow-up examination. We recommend simple decompression of the nerve in cases without deformity of the elbow, as this is the less invasive operative procedure.

Traumatic brain injury: cause or risk of Alzheimer's disease? A review of experimental studies.

Traumatic Brain Injury is the leading cause of death and disability among young individuals in our society. Moreover, according to some epidemiological studies, head trauma is one of the most potent environmental risk factors for subsequent development of Alzheimer's disease. Interestingly, pathological features that are present also in Alzheimer's disease (in particular deposition of beta-amyloid protein) were observed in traumatised brains already a few hours after the initial insult. The primary objective of this review is to present methodology and results of numerous recent human and animal studies dealing with this issue. Special emphasis was placed on head trauma experiments in transgenic mouse models of Alzheimer's disease. We further evaluate the connection between traumatic brain insults and subsequent development of dementia and try to differentiate between primary and secondary pathological mechanisms.

Epidemiology and prevention of fatal head injuries in Germany--trends and the impact of the reunification.

UNLABELLED: A review of the data published on the epidemiology of traumatic brain injuries (TBI) reveals that the data of almost all studies are drawn from local or regional series. Nationwide data are rarely available, or are extrapolated from regional data. In Germany, there has been a nationwide mortality register with ICD-9-coded diagnoses since 1968. In addition, it has been compulsory since 1994 that all hospitals in Germany provide ICD-9 data on all admissions and discharges. Based on data provided by the Federal Bureau of Statistics (Statistisches Bundesamt) in Wiesbaden, all head injuries between 1972 and 1998 were analyzed according to ICD-9 and after 1998 according to the updated ICD-10. The data of hospitalized cases and fatal cases were correlated with population data to calculate incidences and mortality rates. Age-group specific data were also available and analyzed. Head injuries in Germany accounted in 1998 for 19.59% of all injuries. The incidence is 337/100,000. The incidence rate of serious head injury is 33.5/100,000. Mortality decreased continuously from 27.2/100,000 in 1972 to 9.0/100,000 in 2000. The mortality is highest in the group older than 75 years. 68.4% of persons with head injury die before admission to a hospital. After the reunification in 1989/1990, the number of fatal head injuries showed a temporary increase. The number of patients treated in-hospital remained essentially unchanged (276/564 patients in 1998). The majority of hospitalized patients suffered minor head injury. CONCLUSION: Analysis of the admission/discharge data of all German hospitals reveals surprising inside views of age group-related incidence and mortality rates of head injuries in this country. Future research should be focused on patients with minor head injuries who account for nearly 200,000 cases of in-hospital treatment.

Gravitational shunt management of long-standing overt ventriculomegaly in adult (LOVA) hydrocephalus.

OBJECTIVES: Recently a new subtype of chronic hydrocephalus was described: long-standing overt ventriculomegaly in adults (LOVA). Experience to date has indicated that shunt therapy was contraindicated, due to over-drainage. Therefore we investigated whether this problem could be overcome using gravitational shunts. MATERIALS AND METHODS: Thirty macrocephalic adults (17-72 years of age), suffering from progressive hydrocephalus were managed with two different gravitational shunts. The post-operative observation period was 5-87 months. RESULTS: Only two patients developed hygromas, and only one of these required surgical shunt revision. Eighty-seven percent of patients had a long-lasting clinical improvement. Ventricular size was only slightly reduced in 29 patients. There was no correlation between reduction in ventricular size and clinical improvement. CONCLUSION: Contrary to clinical guidelines issued to date, we demonstrate that LOVA can be treated reliably with gravitational shunts, making them a genuine alternative to endoscopic third ventriculostomy (ETV).

[Function of the facial nerve after operative treatment of acoustic neurinomas. Influence of intraoperative monitoring]. / Funktion des N. facialis nach operativer Therapie des Akustikusneurinoms. Bedeutung des intraoperativen Monitorings.

The aim of this study was to evaluate the influence of intraoperative monitoring on the function of the facial nerve after surgical treatment of acoustic neurinomas, classified according to the grading system of Stennert. One hundred thirty patients were divided into two groups. The first group underwent surgery without intraoperative facial monitoring; the second group included intraoperative facial monitoring. Concerning degree of paresis, preoperatively there was no statistically significant difference between the two groups (group 1: 0.77+/-1.5; group 2: 0.4+/-1.2). Despite structural preservation of the facial nerve, postoperative deterioration of its function was observed which consecutively improved postoperatively. Postoperatively, the mean degree of paresis increased to 4.4+/-3.0 in group 1 and 2.4+/-2.3 in group 2. For better understanding of the role of intraoperative monitoring, we investigated the outcome of patients with acoustic neurinomas who underwent surgery over the following 6 months postoperatively. At that time, function improved by 4.1+/-3.2 (group 1) and 2.0+/-2.3 (group 2). We could show that intraoperative monitoring of the facial nerve was a significant factor for better postoperative function in patients undergoing microsurgical excision of neurinomas (P=0.001) .