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Ronald H. M. A. Bartels

✓ The author describes a simple solution for retrieving a cervical polyaxial screw that could not otherwise be easily extracted.

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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.

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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.

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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.

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Ronald H. M. A. Bartels

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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.

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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.

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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.

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Ronald P. Benitez, Rocco A. Armonda, James Harrop, Jeffrey E. Thomas and Robert H. Rosenwasser

Carotid endarterectomy for atherosclerotic occlusive disease has become the standard of care for the treatment of symptomatic and asymptomatic occlusive disease of the carotid bifurcation, based on the results of the North American Symptomatic Carotid Endarterectomy Trial, as well as the Asymptomatic Carotid Atherosclerosis Study. For surgical treatment to be of benefit, the perioperative complication rate for neurological events should be 6% or less in the symptomatic population and 3% or less in the asymptomatic group. The performance of carotid endarterectomy for recurrent stenosis and radiation-induced stenosis has reported neurological events ranging from 4 to 10%. It is in this particular population that carotid angioplasty and stent placement may play a role.

The authors performed a retrospective analysis of 11 patients who underwent carotid angioplasty and stent placement for recurrent or radiation-induced stenosis. One patient in whom endarterectomy was performed by the vascular surgery service had a critical stenosis distal to the endarterectomy site and awoke with a neurological deficit. This patient underwent reexploration and placement of a stent in the artery distal to the arteriotomy site.

The follow-up period ranged from 7 to 12 months. Patient age ranged from 65 to 77 years (mean 75 years). Five of eight patients underwent angioplasty and stent placement for recurrent atherosclerotic disease. Two patients had radiation-induced stenosis, and one patient had a stent placed intraoperatively. All patients, with the exception of the one who underwent intraoperative stent placement, had posttreatment stenoses of less than 15%. The surgical patient had a 30% residual stenosis distally. There were no intra- or postoperative transient ischemic attacks, major or minor strokes, or deaths.

Patients who have recurrent or radiation-induced stenosis are potential candidates for angioplasty and stent placement. Before this can be recommended as an alternative to surgical correction, a longer follow-up period is required.

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Mark G. Burnett, Sherman C. Stein and Ronald H. M. A. Bartels


Standard treatment options for patients with lumbar spinal stenosis include nonoperative therapies as well as decompressive laminectomy. The introduction of interspinous decompression devices such as the X-STOP has broadened treatment options, but data comparing these treatment strategies are lacking. The object of this study was to provide a cost-effectiveness analysis of laminectomy, interspinous decompression, and nonoperative treatment for patients with lumbar stenosis.


The authors performed a structured literature review of lumbar stenosis and constructed a cost-effectiveness model. Using conservative treatment, decompressive laminectomy, and placement of X-STOP as the treatment arms, their primary analysis evaluated the optimal treatment strategy for a patient with lumbar stenosis at a 2-year time horizon. Secondary analyses were done to compare cases in which patients required single-level procedures with those in which multilevel procedures were required as well as to examine the outcomes for a 4-year time horizon. Outcomes were calculated using quality-adjusted life years and costs were considered from the perspective of society.


Laminectomy was found to be the most effective treatment strategy, followed by X-STOP and then conservative treatment at a 2-year time horizon. Both surgical procedures were more costly than conservative treatment. Because laminectomy was both more effective and less costly than X-STOP, it is said to dominate overall. When single level procedures were considered alone, laminectomy was more effective but also more costly than X-STOP.


Lumbar laminectomy appears to be the most cost-effective treatment strategy for patients with symptomatic lumbar spinal stenosis.