✓ The author describes a simple solution for retrieving a cervical polyaxial screw that could not otherwise be easily extracted.
Ronald H. M. A. Bartels
Ronald H. Bartels, T. Rob de Jong and J. André Grotenhuis
✓ Only 44 cases of spinal subdural abscess have been reported to date. The authors present another case and review the relevant literature. The findings of intraspinal gassification on computerized tomography scans and Escherichia coli as the causative organism have not previously been described in relation to spinal subdural abscess. Most frequently, Staphylococcus aureus is the responsible organism. Hematogenous spread of infection from a distant source often takes place. In a surprising number of incidences, iatrogenic causes are the primary foci of spinal subdural abscess.
Spinal subdural abscess is an unpredictable disease, with an unfavorable outcome if left untreated. If there is suspicion of a spinal subdural abscess, urgent radiological examination followed by immediate surgical drainage and appropriate antibiotic therapy is warranted.
Report of three cases
Ronald H. M. A. Bartels and Roland Donk
✓ Postinjury cervical spine instability typically requires surgical treatment in the acute or semiacute stage. The authors, however, report on three patients with older (> 8 weeks) untreated bilateral cervical facet dislocation. In two patients they attempted a classic anterior-posterior-anterior approach but failed. The misalignment in the second stage of the procedure could not be corrected, and they had to add a fourth, posterior, stage. To avoid the fourth stage, thereby reducing operating time and risk of neurological damage while turning the patient, they propose the following sequence: 1) a posterior approach to perform a complete facetectomy bilaterally with no attempt to reduce the dislocation; 2) an anterior microscopic discectomy with reduction of the dislocation and anterior fixation; and 3) posterior fixation. This sequence of procedures was successfully performed in the third patient. Based on this experience, they suggest that in cases of nonacute bilateral cervical facet dislocations the operating sequence should be posterior-anterior-posterior.
Ronald H. M. A. Bartels and Jacobus J. Van Overbeeke
✓ The vein of Labbé is a very important structure and every neurosurgeon is acquainted with its anatomy. Because of the recent increasing interest and experience in skull base surgery, the vein of Labbé has received a great deal of attention. Intraoperative damage to this vein should be avoided and several methods to prevent this have been described. Despite these developments, nothing is written in the neurosurgical literature about the man who described this vein for the first time: Charles Labbé. The authors therefore conducted an extensive search of the literature and uncovered several public records in France to learn more about Charles Labbé.
Ronald H. M. A. Bartels and Jan Goffin
Anterior cervical discectomy with fusion (ACDF) is a very well-known and often-performed procedure in the practice of spine surgeons. The earliest descriptions of the technique have always been attributed to Cloward, Smith, and Robinson. However, in the French literature, this procedure was also described by others during the exact same time period (in the 1950s).
At a meeting in Paris in 1955, Belgians Albert Dereymaeker and Joseph Cyriel Mulier, a neurosurgeon and an orthopedic surgeon, respectively, described the technique that involved an anterior cervical discectomy and the placement of an iliac crest graft in the intervertebral disc space. In 1956, a summary of their oral presentation was published, and a subsequent paper—an illustrated description of the technique and the details of a larger case series with a 3.5-year follow-up period—followed in 1958.
The list of authors who first described ACDF should be completed by adding Dereymaeker’s and Mulier’s names. They made an important contribution to the practice of spinal surgery that was not generally known because they published in French.
Ronald H. M. A. Bartels, Roland Donk and Roel van Dijk Azn
Object. The authors evaluate the effects of implantation of a carbon fiber cage after anterior cervical discectomy (ACD) on the height of the foramen and the angulation between endplates of the disc space.
Methods. Thirteen consecutive patients who were scheduled for standard microscopic ACD and interbody fusion underwent thin-slice (1.5 mm) spiral computerized tomography scanning 1 day preoperatively, 1 day postoperatively, and 1 year postoperatively. Oblique sagittal reconstructions were made through both foramina; the height of each foramen and the angle between the endplates were measured. Because 16 cages were implanted, 32 foramina were investigated. Preoperatively, the mean height of the foramina (± standard deviation) was 8.1 ± 1.5 mm (range 5.7–12 mm), and at 1 day postoperatively it was 9.7 ± 1.4 mm (range 7.5–12.8 mm). This difference reached statistical significance (p < 0.0005). The mean foraminal height after 1 year was 9.4 ± 1.4 mm (range 6.9–12.7 mm). In terms of the preoperative value, the 1-year measurement still reached statistical difference (p < 0.005) but not with the direct postoperative mean foraminal height. Preoperatively the mean value of the angle between the two adjacent endplates was 1.3 ± 2.4° (range 0–8°), and postoperatively it was 7.8 ± 2.9° (range 2–12°), which was statistically significant (p < 0.0005).
Conclusions. The cervical carbon fiber cage effectively increased the height of the foramen even after 1 year, which contributed to decompression of the nerve root. The wedge shape of the device may contribute to restoration of lordosis.
Amadeo C. Nacimiento, Matthias Bartels, Hans-Dietrich Herrmann and Friedrich Loew
✓ In cats in which the spinal cord was transected at C-1, the exposed L-7 spinal cord segment was compressed with an electromagnetically driven rod applied to the dorsal surface of the segment. With the magnitude of compression constant at 3 mm, the cord was compressed for durations of 50 msec, 0.5 sec, or 1.0 sec. Polysynaptic reflex discharges integrated in the injured segment and action potentials conducted in dorsal column axons traversing the same region were electrophysiologically measured before, during, and for 4½ hours after trauma. Structural changes were evaluated on frozen serial sections obtained both from compressed segments and from tissue adjacent to the injury. At a compression duration of 50 msec, the amplitude of evoked reflex activity decreased abruptly, and dorsal column axonal conduction was blocked for 1 minute following compression. This early-phase response was followed by partial recovery of both functions which persisted until the end of the experiment. Prolonging compression to 0.5 sec brought about a further decrease of polysynaptic reflex activity. Axonal conduction was also decreased, but not significantly. With compression lasting 1.0 sec, no significant changes in reflex discharges and axonal conduction occurred compared with those measured at 0.5 sec. Neither function was abolished, even after the longest compression time. Prolongation of compression significantly increased both the intensity and the spread of edema, whereas changes in hemorrhage were not significant. Thus, a plateau rather than a progressive increase in severity of functional and structural posttraumatic changes was reached by increasing the duration of compression. This injury model reduces the sources of variability found in other experimental compression trauma models and permits the quantitative assessment of basic spinal cord mechanisms and correlated histopathological changes in the same preparation following trauma.
Ronald H. M. A. Bartels, Johannes L. Merx and Jacobus J. van Overbeeke
Object. Occipital encephaloceles are relatively frequently encountered. Many investigators have addressed the embryogenesis of these formations, but the dural system has never before been studied. In this retrospective analysis the authors sought to gain a better understanding of the origins of these defects.
Methods. The charts and radiological examinations, especially the magnetic resonance venography studies, were reviewed in seven patients. In six patients the straight sinus was absent. Drainage of the galenic system took place through a sinus within the falx, also known as a falcine sinus. The tentorium was not seen in five patients.
Conclusions. The combination of an absent straight sinus and dysplastic tentorium is no coincidence: both develop within the same mesenchyme in the mesencephalic flexure. Distortion of the mesenchyme by a neural tube defect, causing an occipital encephalocele, will lead not only to disorders of the tentorium but also of the straight sinus.
Ronald H. M. A. Bartels, Thomas Menovsky, Jacobus J. Van Overbeeke and Wim I. M. Verhagen
Object. Surgical treatment for cubital ulnar nerve compresson includes medial epicondylectomy, simple decompression, or anterior transposition (subcutaneous, intramuscular, or submuscular). There is a dearth of prospective randomized studies on which to base guidelines for choosing one operative treatment over another. The authors review the literature on this subject and present their findings.
Methods. The authors reviewed the literature from January 1970 to July 1997. Two authors decided independently whether an article should be included for review based on previously formulated inclusion and exclusion criteria. In addition to demographic information, data concerning preoperative status and outcome were extracted. For statistical analyses chi-square and Kruskal—Wallis tests were performed.
Irrespective of their preoperative status, patients with simple decompression had the best outcome, whereas those with anterior subcutaneous and submuscular transposition had the worst. If outcome was related to the patient's preoperative status, a significant difference was not found among the various groups for those patients with a preoperative McGowan Grade 2. However, for those with McGowan Grade 3 (severe) symptoms, patients with anterior intramuscular transposition had the best outcome followed by those with simple decompression and anterior submuscular transposition. Statistical analysis was not possible for patients with McGowan Grade 1 because of the small numbers of patients in several treatment modality groups.
Conclusions. Formulating a uniform guideline for operative treatment is not possible based on the results of this study. However, the authors believe that support is given to their policy, which is primarily to perform a simple decompression. Its surgical simplicity with preservation of the anatomy, especially the vascularization, and the possibility of rapid postoperative rehabilitation are also taken into consideration. If subluxation is found intraoperatively, anterior transposition is proposed.