Use of the Telescopic Plate Spacer in Treatment of Cervical and Cervicothoracic Spine Tumors:

Vertebral Body Replacement With an Anchored Expandable Titanium Cage in the Cervical Spine: A Clinical and Radiological Evaluation

BACKGROUND

Expandable cervical cages have been used successfully to reconstruct the anterior spinal column.

OBJECTIVE

To perform clinical and radiological evaluation of vertebral body replacement with an anchored expandable titanium cage in the cervical spine after single-level and 2-level corpectomies.

METHODS

Between 2011 and 2017, 40 patients underwent a single-level (N = 32) or 2-level (N = 8) anterior corpectomy and fusion using an anchored expandable vertebral body replacement cage. Clinical and radiological data at admission, postoperatively, and at 3- and 12-mo follow-up were retrospectively analyzed. Clinical assessment was performed via standardized neurological evaluation, Odom score, and McCormick classification. Radiological assessment was performed via evaluation of sagittal profile, postoperative position, fusion, and subsidence rates.

RESULTS

Mean last follow-up was 14.8 ± 7 mo. Overall clinical and myelopathy-related improvements were shown directly after operation and at last follow-up. A stable centralized positioning of cages was achieved in 37 patients (93%). A mild ventral (>1.5 mm) malplacement was noted in 3 patients (7%) without clinical consequences. Sagittal alignment and preoperative cervical kyphosis improved significantly (7.8° gain of lordosis) and remained stable. Mean preoperative height of operated segments increased by 10 mm postoperatively and remained stable. Fusion rate in non-neoplastic patients and subsidence rate at last follow-up comprised 87.5% and 17.8%. With exception of 1 patient suffering from severe osteoporosis and cage subsidence, no patient needed additional secondary stabilization.

CONCLUSION

Anterior corpectomy and fusion by an expandable anchored titanium cage with anchor screws without additional instrumentation resulted in overall clinical improvement and radiological anterior column support, achieving significant and reliable restoration of the physiological sagittal cervical profile.

Posterior occiput-cervical fixation for metastasis to upper cervical spine

Background:

Metastasis to craniocervical area may result in instability manifesting as disabling pain, cranial nerve dysfunction, paralysis, or even death. Stabilization is required to prevent complications. Nonoperative treatment modalities are ineffective in providing stability and adequate pain relief. We present our experience of diagnosis, presentation, and surgical management for metastatic tumors to the upper cervical spine (UCS).

Methods:

Single-center single-surgeon database of consecutively operated posterior occiput-cervical fusion for metastasis to UCS was reviewed from 2007 to 2016. Demographics, clinical, and surgical data were collected through chart review. Pain scores based on Visual Analog Scale (VAS) and other radiological data were noted. Kaplan–Meier curve was used for survival analysis. Clinical outcomes and complications were recorded.

Results:

A total of 29 patients (17 females/12 males) had the mean age of 56.7 ± 13.5 (24–82). Predominant metastasis included from the breast in 9 (31.03%) cases, followed by renal in 5, melanoma in 4, and 3 each from lung and colon. Axis was involved in 24 cases (C2 body in 21, pedicle in 8 cases). Atlas was involved in 9 cases (lateral mass in 8 cases and arch in 3 cases) and occiput was involved in three cases. Average Spinal Instability Neoplastic Score was 10 ± 2.3 (7–14). Mild cord compression was seen in 7 cases. Fusion extended from occiput to C4 fusion (n = 23), C5 (n = 5), and C6 (n = 1). Average blood loss was 364.8 ± 252.1 ml and operative time was 235 ± 51.9 min. Average length of stay was 7 ± 2.8 days (3–15). VAS improved from 8.3 ± 1.5 to 1 ± 1.1 (P < 0.001). C2 angulation corrected from 2.1° ±5.3° (0°–17°) to 0.5° ±1.2° (P = 0.045). Three patients each developed cardiopulmonary complications and deep infection. The average survival was 14.5 ± 15.1 (0.15–50) months.

Conclusion:

C2 body is the most common site of metastasis. Occiput-cervical fusion for unstable upper cervical metastasis offers a good palliative treatment for pain relief and improved quality of life.

Bone graft options for spinal fusion following resection of spinal column tumors: systematic review and meta-analysis

OBJECTIVE With the advent of new adjunctive therapy, the overall survival of patients harboring spinal column tumors has improved. However, there is limited knowledge regarding the optimal bone graft options following resection of spinal column tumors, due to their relative rarity and because fusion outcomes in this cohort are affected by various factors, such as radiation therapy (RT) and chemotherapy. Furthermore, bone graft options are often limited following tumor resection because the use of local bone grafts and bone morphogenetic proteins (BMPs) are usually avoided in light of microscopic infiltration of tumors into local bone and potential carcinogenicity of BMP. The objective of this study was to review and meta-analyze the relevant clinical literature to provide further clinical insight regarding bone graft options. METHODS A web-based MEDLINE search was conducted in accordance with preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines, which yielded 27 articles with 383 patients. Information on baseline characteristics, tumor histology, adjunctive treatments, reconstruction methods, bone graft options, fusion rates, and time to fusion were collected. Pooled fusion rates (PFRs) and I² values were calculated in meta-analysis. Meta-regression analyses were also performed if each variable appeared to affect fusion outcomes. Furthermore, data on 272 individual patients were available, which were additionally reviewed and statistically analyzed. RESULTS Overall, fusion rates varied widely from 36.0% to 100.0% due to both inter- and intrastudy heterogeneity, with a PFR of 85.7% (I² = 36.4). The studies in which cages were filled with morselized iliac crest autogenic bone graft (ICABG) and/or other bone graft options were used for anterior fusion showed a significantly higher PFR of 92.8, compared with the other studies (83.3%, p = 0.04). In per-patient analysis, anterior plus posterior fusion resulted in a higher fusion rate than anterior fusion only (98.8% vs 86.4%, p < 0.001). Although unmodifiable, RT (90.3% vs 98.6%, p = 0.03) and lumbosacral tumors (74.6% vs 97.9%, p < 0.001) were associated with lower fusion rates in univariate analysis. The mean time to fusion was 5.4 ± 1.4 months (range 3-9 months), whereas 16 of 272 patients died before the confirmation of solid fusion with a mean survival of 3.1 ± 2.1 months (range 0.5-6 months). The average time to fusion of patients who received RT and chemotherapy were significantly longer than those who did not receive these adjunctive treatments (RT: 6.1 months vs 4.3 months, p < 0.001; chemotherapy: 6.0 months vs 4.3 months, p = 0.02). CONCLUSIONS Due to inter- and intrastudy heterogeneity in patient, disease, fusion criteria, and treatment characteristics, the optimal surgical techniques and factors predictive of fusion remain unclear. Clearly, future prospective, randomized studies will be necessary to better understand the issues surrounding bone graft selection following resection of spinal column tumors.

Reconstruction with expandable cages after single- and multilevel corpectomies for spinal metastases: a prospective case series of 60 patients

BACKGROUND CONTEXT

Expandable cages are widely used to reconstruct the spine after the removal of vertebral metastases. Long-term results, however, are lacking, and there is little information on reconstruction after multilevel corpectomies.

PURPOSE

To determine long-term outcome for reconstruction of the spine with expandable cages after single and multilevel corpectomies for spinal metastases.

STUDY DESIGN

A prospective cohort study of 60 consecutive patients with spinal metastases treated with expandable cages.

METHODS

All patients were prospectively followed with regular clinical and radiographic evaluation. Outcome measures were the Frankel score, patients' self-reported recovery, radiological alignment of the spine, and neurologic plus biomechanical complications.

RESULTS

Sixty patients were treated with expandable cages in our hospital in a 5-year period with a maximum follow-up of 6 years. Single-level reconstruction was performed in 48 cases, 2-level in 8, and 3-level in 4. Postoperatively, the Frankel score had improved significantly (p=.03), the segment height had increased (p=.02), and, in severe cases of kyphosis (>20°), the regional angulation had been corrected compared with preoperatively (p<.001). Complication rate, however, was high (36.7%), in particular after multilevel reconstruction, in which three cases had to be reoperated years after the initial surgery; reasons for this were hardware failure, progressive kyphosis, and bronchial perforation. Good recovery was reported in 70% of all patients.

CONCLUSIONS

Expandable cages can be used successfully in reconstruction of the spine after single and multilevel corpectomies for spinal metastases. However, long-term complication rate is high. Promotion of bony fusion, prevention of soft-tissue damage, adequate posterior stabilization, and careful patient selection may reduce these complications.

The use of expandable cages in patients undergoing multilevel corpectomies for metastatic tumors in the cervical spine

Expandable cages have been used successfully to reconstruct the anterior spinal column in the treatment of traumatic, neoplastic, infectious, and degenerative spine disease. To the best of our knowledge, no studies report the results of the use of expandable cages in patients undergoing multilevel corpectomies for cervical spine metastatic disease. We report our experience with the use of expandable cages in this subgroup of patients.From August 2006 to May 2008, 5 patients presenting with myelopathy, pain, and/or radiculopathy secondary to metastatic disease of the cervical spine underwent multilevel cervical corpectomies and placement of expandable cages in our institution. All procedures were supplemented with an anterior cervical plate and with posterior instrumentation to achieve a 360 degrees fusion. A visual analog scale (VAS), Nurick grade, Frankel grade, American Spinal Injuries Association (ASIA) grade, and Ranawat grade were used to evaluate patients pre- and postoperatively. The mean follow-up period was 13.2 months. Three patients underwent a 2-level corpectomy, 1 a 3-level corpectomy, and 1 a 4-level corpectomy. Postoperative imaging studies showed that all patients had correction of preoperative kyphosis. The mean VAS score was reduced from 6.4 to 1. All other indices of spinal cord injury measured improved postoperatively or were stabilized. Postoperative imaging studies showed stable constructs in 4 patients.The use of expandable cages in multilevel corpectomies for the treatment of metastatic cervical spine disease appears to be a safe and effective way to reconstruct the anterior column of the cervical spine, preventing further neurologic deterioration.

Treatment of spinal tumors using cyberknife fractionated stereotactic radiosurgery: pain and quality-of-life assessment after treatment in 200 patients

OBJECTIVE

Benign and malignant tumors of the spine significantly impair the function and quality of life of many patients. Standard treatment options, including conventional radiotherapy and surgery, are often limited by anatomic constraints and previous treatment. Image-guided stereotactic radiosurgery using the CyberKnife system (Accuray, Inc., Sunnyvale, CA) is a novel approach in the multidisciplinary management of spinal tumors. The aim of this study was to evaluate the effects of CyberKnife stereotactic radiosurgery on pain and quality-of-life outcomes of patients with spinal tumors.

METHODS

We conducted a prospective study of 200 patients with benign or malignant spinal tumors treated at Georgetown University Hospital between March 2002 and September 2006. Patients were treated by means of multisession stereotactic radiosurgery using the CyberKnife as initial treatment, postoperative treatment, or retreatment. Pain scores were assessed by the Visual Analog Scale, quality of life was assessed by the SF-12 survey, and neurological examinations were conducted after treatment.

RESULTS

Mean pain scores decreased significantly from 40.1 to 28.6 after treatment (P < 0.001) and continued to decrease over the entire 4-year follow-up period (P < 0.05). SF-12 Physical Component scores demonstrated no significant change throughout the follow-up period. Mental Component scores were significantly higher after treatment (P < 0.01), representing a quality-of-life improvement. Early side effects of radiosurgery were mild and self-limited, and no late radiation toxicity was observed.

CONCLUSION

CyberKnife stereotactic radiosurgery is a safe and effective modality in the treatment of patients with spinal tumors. CyberKnife offers durable pain relief and maintenance of quality of life with a very favorable side effect profile.

VERTEBRAL BODY REPLACEMENT SYSTEMS WITH EXPANDABLE CAGES IN THE TREATMENT OF VARIOUS SPINAL PATHOLOGIES

OBJECTIVE

Vertebral body reconstruction after corpectomy has become a common surgical procedure. The authors describe a prospectively followed case series of patients treated with expandable cages for various indications.

METHODS

Sixty patients underwent single or multilevel corpectomy for degenerative stenosis (13 patients), herniated disc (7 patients), deformity (14 patients), traumatic fracture (3 patients), infection (1 patient), or tumor (22 patients). Six different expandable vertebral body systems were used in the cervical spine (41 patients), thoracic spine (15 patients), and lumbar spine (4 patients). All patients were evaluated clinically and radiographically.

RESULTS

Thirty-nine patients underwent single-level corpectomy, 18 patients underwent two-level corpectomy, and 3 patients underwent three-level corpectomy. Anterior reconstruction alone was performed in 30 patients; circumferential reconstruction was performed in 30 patients, 9 of whom underwent reconstruction through a posterior approach only. At the time of the final follow-up examination (mean, 9 mo), the Nurick grade improved significantly. Ninety-five percent of the patients maintained or improved their Frankel score and 67% had good clinical results. The regional angulation was corrected significantly (4.0 ± 9.0 degrees, P = 0.002), and the segment height increased significantly (3.5 ± 8.0 mm, P = 0.002). Bony fusion was achieved in 93% of the cases. Subsidence was documented in nearly half of the patients (1.4 ± 2.0 mm) and was reduced after circumferential fusion (0.9 ± 1.9 mm, P = 0.08). Eighteen patients (30%) had complications and 12 patients (20%) underwent revision surgery.

CONCLUSION

Expandable vertebral body replacement systems can provide solid anterior column constructs with restoration of height and sagittal alignment. Favorable clinical outcome was shown in most patients, although the complication and reoperation rates are rather high.

Comparison of multisegment anterior cervical fixation using bone strut graft versus a titanium rod and buttress prosthesis: analysis of outcome with long-term follow-up and interview by independent physician

STUDY DESIGN

A retrospective study of 73 consecutive patients who underwent cervical corpectomy and anterior strut fixation over 3 or more disc levels between July 1989 and May 1999.

OBJECTIVE

To compare the efficacy of cervical spine fixation by autologous strut graft from iliac crest or fibula versus a titanium prosthesis without bone graft.

SUMMARY OF BACKGROUND DATA

Strut grafting after multilevel anterior cervical corpectomy remains a challenging procedure, with published dislocation rates from 0% to 71%, and nonunion from 0% to 54%. This paper describes a quicker and easier alternative to the use of a bone strut, imparting a very high degree of immediate spinal stability, and osseous integration equivalent to bone fusion.

METHODS

Thirty-eight bone-graft operations and 38 titanium prosthesis operations were performed on 73 patients between July 24, 1989 and May 20, 1999. Average follow-up was 53.2 months (range 19.8-134).

RESULTS

The group of patients who received the prosthesis was significantly older than the bone-grafted group and required significantly more segments excised, but operation times were significantly shorter than for the bone strut operation. The titanium prosthesis had a lower incidence of dislodgement in the early postoperative period (1/38 vs. 4/38 for bone struts) but a higher rate of late reoperation (4/38 vs. 1/38 for bone struts). The SF-36 scores in the domain of Physical Function (only) were significantly higher in the bone-grafted group (P = 0.016, Mann Whitney), consistent with the difference in mean ages of the 2 groups. The groups were indistinguishable by Odom criteria, patient verdict, pain scores, analgesic intake, length of hospital stay, radiologic fusion rate, and residual symptoms.

CONCLUSION

A titanium rod and buttress prosthesis may be a faster and easier alternative to conventional iliac crest/fibula autograft after multisegmental cervical vertebral corpectomy.

Implantation of a distractible titanium cage after cervical corpectomy: technical experience in 20 consecutive cases

BACKGROUND

This prospective observational study was undertaken to investigate the advantages, the safety, and the drawbacks of reconstructing a cervical corpectomy with a distractible corpectomy cage. According to the author's literature search, this is the second clinical report on a distractible cervical corpectomy cage.

METHOD

20 Consecutive patients underwent a single- or multi-level cervical corpectomy for spondylotic myelopathy, traumatic fracture, or tumor. The corpectomy defect was reconstructed by means of a distractible titanium cage, and local bone from the corpectomy was layed around the cage for fusion. An anterior cervical plate and/or a posterior lateral mass or pedicle screw fixation was added in all patients. The average follow-up was 14 months, and all patients had at least 12 months of follow-up.

FINDINGS

No hardware failure occurred in any of the patients. Construct stability was achieved in 19 out of 20 patients (95%) at 12 months postoperatively. The mean regional lordosis was 1 degrees preoperatively, 9 degrees postoperatively, and 7 degrees at the follow-up. Mean neck pain on a VAS was 3.9 preoperatively, and 2.6 at 12 months. There were three perioperative complications: transient neurological worsening in one patient, one transient vocal cord paralysis, and persistent dysphagia in one patient.

CONCLUSION

A single- or multi-level cervical corpectomy can be safely and effectively reconstructed by a distractible titanium cage and local bone graft in combination with anterior cervical plating and/or posterior lateral mass/pedicle screw fixation. Potential advantages of this technique are an unforced cage insertion in its non-distracted position, press-fitting the cage into the corpectomy defect through cage distraction, correction of kyphosis or preservation of local lordosis through cage distraction, and the absence of donor site morbidity. However, the stability rate in the current series did not exceed the fusion rates of auto- or allografts.

Cervical spinal metastasis: anterior reconstruction and stabilization techniques after tumor resection

Object

In a review of the literature, the authors provide an overview of various techniques that have evolved for reconstruction and stabilization after resection for metastatic disease in the subaxial cervical spine.

Methods

Reconstruction and stabilization of the cervical spine after vertebral body (VB) resection for metastatic tumor is an important goal in the surgical management of spinal metastasis. Generally, the VB defect is reconstructed with bone autograft or allograft, polymethylmethacrylate (PMMA), interbody spacers, and/or cages. In cases of PMMA-assisted reconstruction, internal devices are used to augment the fixation of PMMA. Stabilization is then achieved with anterior instrumentation, usually an anterior cervical locking plate. In some cases, posterior instrumentation may be necessary to supplement the anterior construct.

Conclusions

Anterior cervical corpectomy followed by reconstruction and stabilization is an effective strategy in the management of spinal metastases in patients.