Anterior Corpectomy and Plating with Carbon-PEEK Instrumentation for Cervical Spinal Metastases: Clinical and Radiological Outcomes

Background: Anterior cervical corpectomy and plating has been recognized as a valuable approach for the surgical treatment of cervical spinal metastases. This study aimed to report the surgical, clinical and radiological outcomes of anterior carbon-PEEK instrumentations for cervical spinal metastases. Methods: Demographical, clinical, surgical and radiological data were collected from 2017 to 2020. The Neck Disability Index (NDI) questionnaire for neck pain, EORTC QLQ-C30 questionnaire for quality of life, Nurick scale for myelopathy and radiological parameters (segmental Cobb angle and cervical lordosis) were collected before surgery, at 6 weeks postoperatively and follow-up. Results: Seventeen patients met inclusion criteria. Mean age was 60.9 ± 7.6 years and mean follow-up was 12.9 ± 4.0 months. The NDI (55.4 ± 11.7 to 25.1 ± 5.4, p < 0.001) scores and the EORTC QLQ-C30 global health/QoL significantly improved postoperatively and at the last follow-up. The segmental Cobb angle (10.7° ± 5.6 to 3.1° ± 2.2, p < 0.001) and cervical lordosis (0.9° ± 6.7 to −6.2 ± 7.8, p = 0.002) significantly improved postoperatively. Only one minor complication (5.9%) was recorded. Conclusions: Carbon/PEEK implants represent a safe alternative to commonly used titanium ones and should be considered in cervical spinal metastases management due to their lower artifacts in postoperative imaging and radiation planning. Further larger comparative and cost-effectiveness studies are needed to confirm these results.

Primary osseous chondrosarcoma in the lumbar spine: case report and literature review with analysis

Primary spinal chondrosarcoma (CS) is rare. Only a few previous case reports have included a detailed description of the surgical process used to treat the CS. In addition, a paucity of documentation exists comparing differences in the outcomes between the approaches in en bloc resection. Here, we present a case of CS in the lumbar (L) spine treated with two-stage (anterior and posterior approach) en bloc surgery and analyze the differences between one-stage and two-stage approaches in the treatment of primary lumbar CS. A 30-year-old male patient with an L3 vertebral body CS presented with back pain and lower limb weakness. Lumbar spine magnetic resonance imaging (MRI) showed an L3 vertebral body tumor with cord and root compression. Two-stage surgery comprising posterior total laminectomy and transpedicular screw fixation over L2–L4 in the first stage, with subsequent anterior corpectomy, cage implantation, and anterior lumbar interbody fusion was performed to achieve total tumor removal and stabilization. The patient’s symptoms improved postoperatively, with no recurrence as of the 2-year follow-up. The analysis of previous similar cases showed that two-stage surgery, compared with one-stage surgery, appears to be beneficial in lumbar spine multisegment disease, providing a lower recurrence rate.

The influence of accessory rods and connectors on the dynamic response of spine fixation

Purpose This study presents a nondestructive technique to assess the influence of accessory rods and connectors on the dynamic response of spine fixation.Methods Eighteen spine specimens were divided into three construct groups such as group I (2 rods [2R]), II (2 primary rods + 2 accessory rods with 2 transverse connectors [4R+2TC]) and III (2 primary rods + 2 accessory rods with 4 transverse connectors [4R+4TC]). Anterior corpectomy was performed for all specimens. A custom test setup was built to assess the dynamic responses of constructs in flexion-extension (FE) and left-right lateral bending (LRLB) motions. This setup can slide in lateral direction, and it is excited with an electrodynamic shaker vibrated at band limited random frequencies. Accelerometer and reusable dynamic strain sensors were installed on constructs to monitor the dynamic responses. Quasi-static eccentric loading tests were performed to determine the range of motion (RoM).Results The results demonstrated that accessory rods significantly increase the resonance frequency (RF) and decrease the strain over standard 2R construction. Although 4R+4TC provided greatest reduction in rod strain over 4R+2TC and 2R, additional 2 connectors have no significant influence on dynamic response in FE motion.Conclusions An increase in the number of rods has a significant role on the improvement of the fixation's integrity in FE and LRLB motions. However, the additional transverse connectors have significant involvements only in LRLB motion. RF obtained from dynamic tests correlated with the RoM which indicates that the technique could be used as an addendum to the quasi-static test.

A novel anatomic titanium mesh cage for reducing the subsidence rate after anterior cervical corpectomy: a finite element study

Fusion with a titanium mesh cage (TMC) has become popular as a conventional method after cervical anterior corpectomy, but postoperative TMC subsidence has often been reported in the literature. We designed a novel anatomic cervical TMC to reduce the postoperative subsidence rate. According to the test process specified in the American Society of Testing Materials (ASTM) F2267 standard, three-dimensional finite element analysis was used to compare the anti-subsidence characteristics of a traditional TMC (TTMC) and novel TMC (NTMC). Through analysis, the relative propensity values of a device to subside (Kp) of the TTMC and NTMC were 665.5 N/mm and 1007.2 N/mm, respectively. A higher Kp measurement is generally expected to indicate that the device is more resistant to subsidence into a vertebral body. The results showed that the novel anatomic titanium mesh cage (NTMC) significantly improved the anti-subsidence performance after anterior cervical corpectomy and fusion (ACCF), which was approximately 51.3% higher than that of the traditional titanium mesh cage.

Surgical management of spinal metastases involving the cervicothoracic junction: results of a multicenter, European observational study

OBJECTIVE Surgical management of spinal metastases at the cervicothoracic junction (CTJ) is highly complex and relies on case-based decision-making. The aim of this multicentric study was to describe surgical procedures for metastases at the CTJ and provide guidance for clinical and surgical management. METHODS Patients eligible for this study were those with metastases at the CTJ (C7–T2) who had been consecutively treated in 2005–2019 at 7 academic institutions across Europe. The Spine Instability Neoplastic Score, neurological function, clinical status, medical history, and surgical data for each patient were retrospectively assessed. Patients were divided into four surgical groups: 1) posterior decompression only, 2) posterior decompression and fusion, 3) anterior corpectomy and fusion, and 4) anterior corpectomy and 360° fusion. Endpoints were complications, surgical revision rate, and survival. RESULTS Among the 238 patients eligible for inclusion this study, 37 were included in group 1 (15%), 127 in group 2 (53%), 18 in group 3 (8%), and 56 in group 4 (24%). Mechanical pain was the predominant symptom (79%, 189 patients). Surgical complications occurred in 16% (group 1), 20% (group 2), 11% (group 3), and 18% (group 4). Of these, hardware failure (HwF) occurred in 18% and led to surgical revision in 7 of 8 cases. The overall complication rate was 34%. In-hospital mortality was 5%. CONCLUSIONS Posterior fusion and decompression was the most frequently used technique. Care should be taken to choose instrumentation techniques that offer the highest possible biomechanical load-bearing capacity to avoid HwF. Since the overall complication rate is high, the prevention of in-hospital complications seems crucial to reduce in-hospital mortality.

Primary Osseous Chondrosarcoma in the Lumbar Spine: Case Report and Literature Review With Analysis

Background Primary spinal chondrosarcoma (CS) is relatively rare, with a reported prevalence rate of less than 10% of all CS. En bloc surgery and resection without entering the tumor capsule typically provides a better prognosis. However, the approaches to such tumor lesions vary. Here, we present a case of CS in the lumbar spine treated with two-stage (anterior and posterior approach) en bloc surgery, along with an analysis and comparison of the characteristics and prognosis of one-stage versus two-stage surgery patients in previous studies. Case description A 30-year-old male with an L3 vertebral body CS presented with back pain and lower limb weakness. Lumbar spine MRI showed an L3 vertebral body tumor with cord and root compression. A two-stage surgery including posterior total laminectomy, transpedicular screw fixation over L2-L4 first with subsequent anterior corpectomy, cage implantation, and anterior lumbar interbody fusion was performed to achieve total tumor removal and stabilization. Pathology revealed a low grade CS with free resection margin. The patient’s symptoms improved after the operation, and no recurrence had occurred as of the two-year follow-up. Furthermore, we also analyzed the post-operative outcomes of 24 cases from previous publications and our current case. Conclusions Two-stage en bloc surgery concomitantly achieves total resection of the tumor, the preservation of neurological function, and a gain in stabilization. The analysis of cases showed that two-stage surgery, in comparison with one-stage surgery, seems to be beneficial in treating L-spine multiple segment disease, providing a lower rate of recurrence.

A novel anatomic titanium mesh cage for reducing the subsidence rate after anterior cervical corpectomy: a finite element study

Fusion with a titanium mesh cage (TMC) has become popular as a conventional method after cervical anterior corpectomy, but postoperative TMC subsidence has often been reported in the literature. We designed a novel anatomic cervical TMC to reduce the postoperative subsidence rate. According to the test process specified in the American Society of Testing Materials (ASTM) F2267 standard, three-dimensional finite element analysis was used to compare the anti-subsidence characteristics of a traditional TMC (TTMC) and novel TMC (NTMC). Through analysis, The relative propensity values of a device to subside (Kp) of the TTMC and NTMC were be 665.5 N/mm and 1007.2 N/mm, respectively. A higher Kp measurement is generally expected to indicate that the device is more resistant to subsidence into a vertebral body. The results showed that the novel anatomic titanium mesh cage (NTMC) significantly improved the anti-subsidence performance after anterior cervical corpectomy and fusion (ACCF), which was approximately 51.3% higher than that of the traditional titanium mesh cage.