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Michael C. Boyd and Paul Steinbok

✓ Choroid plexus tumors are uncommon neoplasms of the central nervous system. A series of 11 cases from the Vancouver General and British Columbia Children's Hospitals, treated during the last 12 years, are reviewed. Some of the management problems commonly encountered with these tumors are discussed. Many of these tumors are associated with severe hydrocephalus at the time of diagnosis, and the perioperative management of this hydrocephalus remains a matter of some debate. The timing of and the necessity for shunting are major considerations. Large subdural fluid collections are often discovered in the postoperative period, and these occasionally cause symptoms of increased intracranial pressure. Reasons for this problem are suggested and possible steps for its prevention are proposed.

The similarity between papillary ependymomas and choroid plexus papillomas has sometimes caused difficulty in pathological diagnosis. Choroid plexus carcinomas, of which there were two in this series, also present a diagnostic challenge. Differential diagnosis affects the further treatment and prognosis for the patient.

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Familial arteriovenous malformations

Report of four cases in one family

Michael C. Boyd, Paul Steinbok and Donald W. Paty

✓ Familial arteriovenous malformations (AVM's) are uncommon entities, with only seven reported cases in the English literature. Some have been associated with hereditary telangiectasia. A family in which AVM's were found in four male members of two generations is reported. In addition, one patient had a large cyst associated with his AVM without previous evidence of acute hemorrhage, which is an uncommon presentation. The family is discussed and a brief review of the literature is presented.

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Christopher S. Bailey, Charles G. Fisher, Michael C. Boyd and Marcel F. S. Dvorak

✓ The purpose of this case report is to demonstrate that an en bloc resection with negative surgical margins can be successfully achieved in a case of a seemingly unresectable C-2 chordoma if appropriate preoperative staging and planning are performed. The management of chordomas is controversial and challenging because of their location and often large size at presentation. Because chordomas are malignant and will aggressively recur locally if intralesional resection is conducted, wide or true en bloc resection is generally recommended. The literature indicates, however, that surgeons are reluctant to perform wide or even marginal resections because of the lesion’s complex surrounding anatomy and the risk of significant neurological compromise when a tumor abuts the dura mater or neural tissues. In this report the authors outline the successful en bloc resection of a large C1–3 chordoma and discuss the importance of preoperative staging and planning.

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Charles Fisher, Vanessa Noonan, Paul Bishop, Michael Boyd, David Fairholm, Peter Wing and Marcel Dvorak

Object. The authors conducted a study to assess health-related quality of life (HRQOL) and the appropriateness of surgery in patients who have undergone elective lumbar discectomy.

Methods. The study involved a prospective cohort of 82 surgically treated patients with lumbar disc herniation causing lower-extremity radiculopathy. An independent study coordinator recorded demographic data and administered the North American Spine Society (NASS) lumbar spine instrument and the Short Form—36 (SF-36) before treatment, and at 6 months and 1 year after surgery. The HRQOL results were also compared with normative data for the NASS and SF-36. The influence of baseline variables on HRQOL was determined using regression modeling. The InterQual Indicators for Surgery and Procedures (ISP) were used to compare surgeon practice patterns with standardized indications for surgery.

The NASS neurogenic symptom (NSS) and pain/disability scores (PDSs) showed very significant improvement at 6 months and little change between 6 months and 1 year. The SF-36 physical function and bodily pain scale scores were associated with the greatest improvement. Interestingly, the 1-year NASS (NSS and PDS) and SF-36 (only PCS) scores remained lower than those of age-matched normative data. Other than preoperative HRQOL scores, the only other variable that inversely influenced HRQOL was the duration of time between symptom onset and surgery. Ninety-five percent of ISP forms were completed, and 97% of the indications recorded by the surgeon matched the criteria.

Conclusions. The reporting of standardized outcomes in association with indications for surgery is feasible and may help elucidate the ideal rate for discectomy.

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Christopher C. Gillis, John T. Street, Michael C. Boyd and Charles G. Fisher

A novel method of spinopelvic ring reconstruction after partial sacrectomy for a chondrosarcoma is described. Chondrosarcoma is one of the most common primary malignant bone tumors, and en bloc resection is the mainstay of treatment. Involvement of the pelvis as well as the sacrum and lumbar spine can result in a technically difficult challenge for en bloc resection and for achievement of appropriate load-bearing reconstruction.

After en bloc resection in their patient, the authors achieved reconstruction with a rod and screw construct including vascularized fibula graft as the main strut from the lumbar spine to the pelvis. Additionally, a cadaveric allograft strut was used as an adjunct for the pelvic ring. This is similar to a modified Galveston technique with vascularized fibula in place of the Galveston rods. The vascularized fibula provided appropriate biomechanical support, allowing the patient to return to independent ambulation. There was no tumor recurrence; neurological status remained stable; and the allograft construct integrated well and even increased in size on CT scans and radiographs in the course of a follow-up longer than 7 years.

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Brian K. Kwon, Charles G. Fisher, Michael C. Boyd, John Cobb, Hilary Jebson, Vanessa Noonan, Peter Wing and Marcel F. Dvorak

Object

Unilateral facet injuries can be treated with either anterior or posterior fixation techniques with reportedly good outcomes. The two approaches have not been directly compared, however, and consensus is lacking as to which is the optimal method. The primary objective of this study was to determine whether acute postoperative morbidity differed between anteriorly and posteriorly treated patients with unilateral facet injuries.

Methods

Forty-two patients were prospectively randomized to undergo either anterior cervical discectomy and fusion or posterior fixation. The primary outcome measure was the postoperative time required to achieve a predefined set of discharge criteria. Secondary outcome measures included postoperative pain, wound infections, radiographically demonstrated fusion and alignment, and patient-reported outcome measures.

Results

The median time to achieve the discharge criteria was 2.75 and 3.5 days for anterior and posterior groups, respectively, a difference that did not reach statistical significance (p = 0.096). Compared with those treated using posterior fixation, anteriorly treated patients exhibited somewhat less postoperative pain, a lower rate of wound infection, a higher rate of radiographically demonstrated union, and better radiographically proven alignment. Nonetheless, the anterior approach was accompanied by a risk of swallowing difficulty in the early postoperative period. Patient-reported outcome measures did not reveal a difference between anterior and posterior fixation procedures.

Conclusions

This prospective randomized controlled trial provided level 1 evidence that both the anterior and posterior fixation approaches appear to be valid treatment options. Although statistical significance was not reached in the primary outcome measure, some secondary outcome measures favored anterior fixation and others favored posterior treatment for unilateral facet injuries.

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Charles Fisher, Sandeep Singh, Michael Boyd, Stephen Kingwell, Brian Kwon, Meng Jun Li and Marcel Dvorak

Object

The use of pedicle screws (PSs) for stabilization of unstable thoracolumbar fractures has become the standard of care, but PS efficacy has not been reported in the upper thoracic spine. The primary outcome of this study was to determine the efficacy of PS fixation to achieve and maintain reduction of unstable upper thoracic spine fractures (T1–5). Secondary outcomes included scores on a 1-year postoperative generic health-related quality of life (QOL) questionnaire and postoperative complications.

Methods

This study was a retrospective analysis and cross-sectional outcome assessment of cases prospectively entered into a spine database from 1997 to 2004. All patients with a traumatic, unstable upper thoracic spine (T1–5) fracture who underwent PS fixation were included. Preoperative CT scans with sagittal plane reformatted images were used to determine kyphotic deformity and compared with immediate postoperative and latest follow-up radiographs or CT scans. Patient charts, operative notes, and the results of postoperative follow-up examinations were reviewed. Patients were mailed the Short Form-36v2 (SF-36 version 2) by an independent study coordinator.

Results

Cases involving 27 patients (23 male, 4 female) were evaluated. The patients' mean age was 39.9 years (range 16–73 years). In all, 251 PSs were passed between T-1 and T-8. The mean true kyphotic deformity was 18.2° preoperatively, 8.7° (p < 0.0005) initially postoperatively, and 10.1° at final follow-up (mean 2.3 years postoperatively). The mean SF-36 physical component summary score was 35.89 while the mental component summary score was 56.43 at a minimum of 1-year postoperatively (mean 3.2 years). There were no intraoperative vascular or neural complications.

Conclusions

In the hands of fellowship-trained spinal surgeons, PS fixation for reduction and stabilization of upper thoracic spine fractures is a safe and efficacious technique. Health-related QOL outcome data are deficient for spine trauma patients and should be an essential component of quantifying treatment outcomes.

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Christopher S. Bailey, Marcel F. Dvorak, Kenneth C. Thomas, Michael C. Boyd, Scott Paquett, Brian K. Kwon, John France, Kevin R. Gurr, Stewart I. Bailey and Charles G. Fisher

Object

The authors compared the outcome of patients with thoracolumbar burst fractures treated with and without a thoracolumbosacral orthosis (TLSO).

Methods

As of June 2002, all consecutive patients satisfying the following inclusion criteria were considered eligible for this study: 1) the presence of an AO Classification Type A3 burst fractures between T-11 and L-3, 2) skeletal maturity and age < 60 years, 3) admission within 72 hours of injury, 4) initial kyphotic deformity < 35°, and 5) no neurological deficit. The study was designed as a multicenter prospective randomized clinical equivalence trial. The primary outcome measure was the score based on the Roland-Morris Disability Questionnaire assessed at 3 months postinjury. Secondary outcomes are assessed until 2 years of follow-up have been reached, and these domains included pain, functional outcome and generic health-related quality of life, sagittal alignment, length of hospital stay, and complications. Patients in whom no orthotic was used were encouraged to ambulate immediately following randomization, maintaining “neutral spinal alignment” for 8 weeks. The patients in the TLSO group began being weaned from the brace at 8 weeks over a 2-week period.

Results

Sixty-nine patients were followed to the primary outcome time point, and 47 were followed for up to 1 year. No significant difference was found between treatment groups for any outcome measure at any stage in the follow-up period. There were 4 failures requiring surgical intervention, 3 in the TLSO group and 1 in the non-TLSO group.

Conclusions

This interim analysis found equivalence between treatment with a TLSO and no orthosis for thoracolumbar AO Type A3 burst fractures. The influence of a brace on early pain control and function and on long-term 1- and 2-year outcomes remains to be determined. However, the authors contend that a thoracolumbar burst fracture, in exclusion of an associated posterior ligamentous complex injury, is inherently a very stable injury and may not require a brace.

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Brian K. Kwon, Armin Curt, Lise M. Belanger, Arlene Bernardo, Donna Chan, John A. Markez, Stephen Gorelik, Gerard P. Slobogean, Hamed Umedaly, Mitch Giffin, Michael A. Nikolakis, John Street, Michael C. Boyd, Scott Paquette, Charles G. Fisher and Marcel F. Dvorak

Object

Ischemia is an important factor in the pathophysiology of secondary damage after traumatic spinal cord injury (SCI) and, in the setting of thoracoabdominal aortic aneurysm repair, can be the primary cause of paralysis. Lowering the intrathecal pressure (ITP) by draining CSF is routinely done in thoracoabdominal aortic aneurysm surgery but has not been evaluated in the setting of acute traumatic SCI. Additionally, while much attention is directed toward maintaining an adequate mean arterial blood pressure (MABP) in the acute postinjury phase, little is known about what is happening to the ITP during this period when spinal cord perfusion pressure (MABP − ITP) is important. The objectives of this study were to: 1) evaluate the safety and feasibility of draining CSF to lower ITP after acute traumatic SCI; 2) evaluate changes in ITP before and after surgical decompression; and 3) measure neurological recovery in relation to the drainage of CSF.

Methods

Twenty-two patients seen within 48 hours of injury were prospectively randomized to a drainage or no-drainage treatment group. In all cases a lumbar intrathecal catheter was inserted for 72 hours. Acute complications of headache/nausea/vomiting, meningitis, or neurological deterioration were carefully monitored. Acute Spinal Cord Injury motor scores were documented at baseline and at 6 months postinjury.

Results

On insertion of the catheter, mean ITP was 13.8 ± 1.3 mm Hg (± SD), and it increased to a mean peak of 21.7 ± 1.5 mm Hg intraoperatively. The difference between the starting ITP on catheter insertion and the observed peak intrathecal pressure after decompression was, on average, an increase of 7.9 ± 1.6 mm Hg (p < 0.0001, paired t-test). During the postoperative period, the peak recorded ITP in the patients randomized to the no-drainage group was 30.6 ± 2.3 mm Hg, which was significantly higher than the peak intraoperative ITP (p = 0.0098). During the same period, the peak recorded ITP in patients randomized to receive drainage was 28.1 ± 2.8 mm Hg, which was not statistically higher than the peak intraoperative ITP (p = 0.15).

Conclusions

The insertion of lumbar intrathecal catheters and the drainage of CSF were not associated with significant adverse events, although the cohort was small and only a limited amount of CSF was drained. Intraoperative decompression of the spinal cord results in an increase in the ITP measured caudal to the injury site. Increases in intrathecal pressure are additionally observed in the postoperative period. These increases in intrathecal pressure result in reduced spinal cord perfusion that will otherwise go undetected when measuring only the MABP. Characteristic changes in the observed intrathecal pressure waveform occur after surgical decompression, reflecting the restoration of CSF flow across the SCI site. As such, the waveform pattern may be used intraoperatively to determine if adequate decompression of the thecal sac has been accomplished.