Cervical Cage Research Articles

Correlation between the ease of cage plates implantation and endplate Hounsfield unit value during ACDF: a retrospective study

ObjectiveTo investigate the correlation between the implantation status of the ROI-C cervical cage plates and the Hounsfield unit(HU) value of the target vertebral endplate during anterior cervical decompression and fusion (ACDF)surgery.MethodsReview of patient data undergoing ACDF from January 2018 to December 2021. Data on gender, age, body mass index, history of hypertension, diabetes, hyperlipidemia, smoking, alcohol consumption, cervical cage plates status, and HU values of the cervical vertebral endplate. Logistic regression analysis was used to evaluate the relationship between the HU values and the plates status.ResultsA total of 17 cases (12.1%) had misplaced implants during surgery. There were statistical differences in gender, long-term smoking history, drinking history, and cervical vertebral endplate HU values between the abnormal implantation group and the normal implantation group (P < 0.05). The cervical vertebral endplate HU values in the abnormal implantation group were significantly higher than those in the normal implantation group (729.3 ± 36.2 HU vs. 484.4 ± 59.2 HU, P < 0.001). In the logistic regression analysis, cervical endplate HU value (OR 1.081; 95% CI 1.016–1.375) was an independent factor influencing improper plate implantation. The area under the ROC curve (AUC) for the cervical endplate HU value in predicting implantation difficulty was 0.836 (P < 0.05), with an optimal threshold of 724 HU (sensitivity 83.2%; specificity 90.4%).ConclusionsThe cervical vertebral segment endplate HU value can independently predict whether the implantation of the plates is misplaced during ACDF surgery.

Cervical ossification of the posterior longitudinal ligament revealed by cervical trauma: A case report with literature review

Background: Ossification of the posterior longitudinal ligament (OPLL) refers to bone formation within the posterior longitudinal ligament of the spinal column. This disease of the cervical spine results in a reduced volume of the spinal canal and can cause spinal cord damage. The onset of cervical OPLL is insidious. OPLL may increase the risk of spinal cord injury with various neurological deficits after minor trauma. An acute event can reveal a previously unknown or paucysymptomatic cervical OLLP. The aim: To present a case of unknown cervical OLLP revealed by cervical trauma after a traffic road accident. Case report: A 47-year-old female presented intractable cervicobrachial neuralgia in the posttraumatic aftermath of a traffic road accident. Computed Tomography (CT) and Magnetic resonance imaging (MRI) demonstrated an isolated OPLL from C5 to C6, causing significant nerve compression operated via anterior approach with discectomy and intervertebral cervical cage. Conclusion: Acute cervical trauma must be considered a mode of revelation of previously unknown or paucisymptomatic cervical OLLP and must be considered in the emergency room.

ACDF Using Stand-Alone PEEK Cervical Cages in Management of Multilevel Cervical Sondylotic Myelopathy

ACDF Using Stand-Alone PEEK Cervical Cages in Management of Multilevel Cervical Sondylotic Myelopathy

Comparison of Three Grafting Options for Anterior Cervical Corpectomy and Fusion: A Retrospective 3-Arms Case Control Study

Anterior cervical corpectomy and fusion achieves foraminal radicular and central medullary decompression and spinal stabilization in staged lesions. Many bone graft materials have been developed for the reconstruction of cervical lordosis and the restoration of intervertebral height after corpectomy. The PolyEtherKetoneEtherKetoneKetone (PEKEKK) is a semicrystalline thermoplastic polymer that can be reinforced with carbon fibers to create long and highly fenestrated rectangular cervical cages for corpectomy. This study aimed to evaluate the radiological outcomes of an innovative PEKEEKK cage compared with others grafting options. Forty-five consecutive patients who underwent surgery with PEKEKK cages between 2017 and 2019 at a spine institution, were matched with 15 patients with a titanium mesh cylindrical cage (TMC) and 15 patients with a tricortical structural iliac bone graft. The restoration of vertebral height and cervical lordosis postoperatively, and subsidence of the construct were evaluated. Complications were reported. The minimal follow-up was 5.1±2years. A better, but nonsignificant, postoperative gain in height was observed for PEKEKK (+8.1 ± 20%) and TMC cages (+8.2 ± 16%) than for iliac crest autograft reconstruction (+2.3 ± 15%, P= 0.119). The mean subsidence at the last follow-up was greater for TMC cages (-10.2 ± 13%), but was not significant, with -6.1 ± 10% for PEKEKK cages and -4.1 ± 7% for iliac crest autografts (P= 0.223). The gain in segmental cervical lordosis was significant (P < 0.001) and remained stable in all the groups. Although an improvement in radiologic anatomical parameters can be achieved with all cage groups, the PEKEKK cage can be considered as a safe alternative for reducing subsidence.

Factors Affecting the Risk of Developing Cervical Cage Malposition in Patients with Cervical Discectomy

Aim: Cervical discectomy followed by cage placement for fusion is nowadays a commonly used method for the treatment of degenerative cervical spine diseases. One of the complications that can be observed during postoperative follow-up is cervical cage subsidence. At this point, it is investigated in this study the relationship between the loss of endplate brightness observed on early postoperative cervical radiographs and the development of cervical cage subsidence during follow-up. Methods: 100 patients who underwent single-level cervical disc herniation surgery between 2013 and 2023 were selected. The patients were divided into two groups based on the presence or absence of cage subsidence in cervical radiographs taken at the 60-day postoperative follow-up. In all patients included in the study, the presence of endplate brightness loss in the cervical radiographs taken within the day 1 of post-surgery period in the vertebrae adjacent to the cage was evaluated and compared between groups. Results: Cage subsidence was detected in 11 patients (11%), while it was not observed in 89 patients (89%). Among the 11 patients with cage subsidence, endplate brightness loss was identified in 8 patients (72.7%), whereas it was found in 10 patients (11.2%) among the 89 patients without cage subsidence. These results indicate a significant relationship between the loss of endplate brightness observed on early radiographs and the occurrence of cervical cage subsidence during later follow-up (p

Interbody Fusion Device in the Treatment of Cervicobrachial Syndrome: A Prospective 5-Year Follow-Up Extension Study of Porous Titanium Cervical Cages

Background: To assess long-term clinical and radiological data of porous titanium cervical interbody cages. Methods: We recruited 34 out of 49 patients previously enrolled in the EFFECT trial on 3D printed titanium cages, for 5 years follow-up. Objectives were the evaluation of Neck Disability Index, Visual Analog Scale of arm pain and neck pain, Likert self-reported perceived recovery, EQ-5D, fusion status and subsidence. Fusion was defined as rotation ≤ 4° and ≤ 1.25 mm translation at the index level, using flexion-extension radiograph. Results: All patients had good outcomes in terms of NDI (12.5±15.4), VAS neck pain (23.5±24.1), VAS arm pain (18.7±20.2) and EuroQol (0.77±0.24). 88.6% of the patients experienced complete or nearly complete recovery. NDI improved significantly at 5 years compared to 1 year, all other outcome measures did not significantly differ from the 12 months results. The fusion rate at the index level increased from 91.5% at 12 months to 100% at 5 years. Conclusion: 3D printed stand-alone porous titanium cervical implants are effective in terms of clinical and radiological outcome with 88.6% complete or nearly complete recovery and fusion rate of 100% at 5 years follow-up. Moreover, solid single level anterior cervical fusion can be achieved without additional plating. Trial Registration: The study has been registered in The Netherlands Trial Register (NTR 1289) and approved by the Medical Ethical Committee (NL76079.058.20).

Exploring the mechanical strength, antimicrobial performance, and bioactivity of 3D-printed silicon nitride-PEEK composites in cervical spinal cages

&amp;nbsp;In this study, our goal was to assess the suitability of a polyether-ether-ketone (PEEK) and silicon nitride (Si3N4) polymer composite for antimicrobial three-dimensional (3D)-printed cervical cages. Generic cage designs (PEEK and 15 vol.% Si3N4-PEEK) were 3D-printed, including solid and porous cage designs. Cages were tested in static compression, compression shear, and torsion per ASTM F2077. For antibacterial testing, virgin and composite filament samples were inoculated with Staphylococcus epidermidis and Escherichia coli. In vitro cell testing was conducted using MC3T3-E1 mouse preosteoblasts, where cell proliferation, cumulative mineralization, and osteogenic activity were measured. The 3D-printed PEEK and Si3N4-PEEK cages exhibited adequate mechanical strength for all designs, exceeding 14.7 kN in compression and 6.9 kN in compression shear. Si3N4-PEEK exhibited significantly lower bacterial adhesion levels, with a 93.9% reduction (1.21 log), and enhanced cell proliferation when compared to PEEK. Si3N4-PEEK would allow for custom fabrication of 3D-printed spinal implants that reduce the risk of infection compared to unfilled PEEK or metallic alloys. &amp;nbsp;

Comparison of adjacent segment degeneration in patients using cervical cage and disc prosthesis in anterior cervical surgery

Comparison of adjacent segment degeneration in patients using cervical cage and disc prosthesis in anterior cervical surgery

Outcomes of stand-alone cervical cage versus cervical cage with plate in single or double level anterior cervical discectomy and fusion: Comparative Study

Outcomes of stand-alone cervical cage versus cervical cage with plate in single or double level anterior cervical discectomy and fusion: Comparative Study

Preliminary exploration of the biomechanical properties of three novel cervical porous fusion cages using a finite element study

BackgroundPorous cages are considered a promising alternative to high-density cages because their interconnectivity favours bony ingrowth and appropriate stiffness tuning reduces stress shielding and the risk of cage subsidence.MethodsThis study proposes three approaches that combine macroscopic topology optimization and micropore design to establish three new types of porous cages by integrating lattices (gyroid, Schwarz, body-centred cubic) with the optimized cage frame. Using these three porous cages along with traditional high-density cages, four ACDF surgical models were developed to compare the mechanical properties of facet articular cartilage, discs, cortical bone, and cages under specific loads.ResultsThe facet joints in the porous cage groups had lower contact forces than those in the high-density cage group. The intervertebral discs in all models experienced maximum stress at the C5/6 segment. The stress distribution on the cortical bone surface was more uniform in the porous cage groups, leading to increased average stress values. The gyroid, Schwarz, and BCC cage groups showed higher average stress on the C5 cortical bone. The average stress on the surface of porous cages was higher than that on the surface of high-density cages, with the greatest difference observed under the lateral bending condition. The BCC cage demonstrated favourable mechanical stability.ConclusionThe new porous cervical cages satifies requirements of low rigidity and serve as a favourable biological scaffold for bone ingrowth. This study provides valuable insights for the development of next-generation orthopaedic medical devices.

Management of hangman's fractures using anchored anterior cervical cages.

Hangman's fractures comprise approximately 20% of C2 fractures and often require surgery to correct significant angulation and/or subluxation. Recently, anchored anterior cervical cages (ACCs) have been used to fuse C2-3 as they reduce the risks of soft-tissue dissection, bone drilling, operative time, and postoperative dysphagia. This single-center and retrospective study (2012-2019) included 12 patients (3 type I, 6 type II, and 3 type IIa fractures) undergoing C2-3 ACCs (zero profile, half plate, full plate). Preoperative and postoperative radiographic and clinical data were analyzed. The 12 patients demonstrated the following findings: a mean operative time of 106 ± 21 min, blood loss averaging 67 ± 58 mL, and mean length of stay of 9.8 ± 7.7 days (6.4 ± 5.5 days in intensive care). The mean differences in preoperative versus postoperative radiographs showed an increase in disc angle (9.0° ± 9.4° vs. 14.0° ± 7.2°), reduction of subluxation (18.5% ± 13.6% vs. 2.6% ± 6.2%), and maintenance of C2-7 lordosis (14.3° ± 9.5° vs. 14.4° ± 9.5°). All patients demonstrated fusion on dynamic films obtained >6 months postoperatively. In addition, only one patient had Grade 0 subsidence, three had transient postoperative dysphagia, whereas none had either intraoperative complications or 90-day readmissions. ACCs proved to be a viable alternative to traditional anterior cervical discectomy/fusion to treat 12 patients with C2-3 hangman's fractures in this preliminary study.

Preservation of Cervical Lordosis in Patients with Multilevel Cervical Spondylosis: Implantation of Anatomical Cervical Cage

Preservation of Cervical Lordosis in Patients with Multilevel Cervical Spondylosis: Implantation of Anatomical Cervical Cage

Are all Cages Created Equal? Analysis of Cervical Cage Malfunctions Using FDA MAUDE Database.

Retrospective case series. To characterize failure rates of cervical cages based on manufacturer and design characteristics using the nationwide database of reported malfunctions. The Food and Drug Administration (FDA) aims to ensure the safety and efficacy of cervical interbody implants postimplantation; however, intraoperative malfunctions may be overlooked. The FDA's Manufacturer and User Facility Device Experience database was queried for reports of cervical cage device malfunctions from 2012 to 2021. Each report was categorized based on the failure type, implant design, and manufacturer. Two market analyses were performed. First, "failure-to-market share indices" were generated by dividing the number of failures per year for each implant material by its yearly US market share in cervical spine fusion. Second, "failure-to-revenue indices" were calculated by dividing the total number of failures per year for each manufacturer by their approximate yearly revenue from spinal implants in the US. Outlier analysis was performed to generate a threshold value above which failure rates were defined as greater than the normal index. In total, 1336 entries were identified, and 1225 met the inclusion criteria. Of these, 354 (28.9%) were cage breakages, 54 (4.4%) were cage migrations, 321 (26.2%) were instrumentation-related failures, 301 (24.6%) were assembly failures, and 195 (15.9%) were screw failures. Poly-ether-ether-ketone implants had higher failure by market share indices for both migration and breakage compared with titanium. Upon manufacturer market analysis, Seaspine, Zimmer-Biomet, K2M, and LDR exceeded the failure threshold. The most common cause of implant malfunction was breakage. Poly-ether-ether-ketone cages were more likely to break and migrate compared with titanium ones. Many of these implant failures occurred intraoperatively during instrumentation, which underscores the need for FDA evaluation of these implants and their accompanying instrumentation under the appropriate loading conditions before commercial approval.

Optimization of cervical cage and analysis of its base material: A finite element study

Nowadays, cervical disorders are common due to human lifestyles. Accordingly, the cage design should be optimized as an essential issue. For an optimal design, an objective function is utilized to calculate the proper geometrical parameters. Additionally, the base material of the cage plays a key role in its functionality and final cost. Novel materials are currently introduced with more compatibility with the bone in terms of mechanical and chemical properties. In this study, a cervical cage was modeled based on PEEK material with three types of tooth designs on its surface. The cervical cage is assumed to be implanted between C6 and C7 vertebrae. The geometric parameters of the cage were optimized to minimize the mass by determining allowable stress and subsidence. The effect of complete cortical removal was investigated as a surgical mistake. Finally, a new composition of PEEK/titanium was introduced as the base material of the cage. Ansys 18.2 was used for FEA. The cage with a straight tooth was chosen due to its lower stress and subsidence compared with other designs. Furthermore, the optimized structures of all three tooth designs were determined. The mass and volume of the optimal cages were reduced by 41.47% and 41.52% respectively. Besides, complete cortical resection should not be carried out during fusion surgery, since it may lead to higher subsidence. The composition of PEEK/titanium was chosen as an appropriate base material due to its better performance compared with PEEK or titanium alone.

Quasi-static loading of glass fiber-reinforced composite cervical fusion cage

ObjectivesAnterior decompression and fusion in cervical spine has become one of the most common procedures in neurosurgery. In the surgery, cervical cage implants made of different biomaterials are used. Our purpose was to create a cervical cage made of glass fiber-reinforced composite (FRC) filled with bioactive glass particles and to characterize its behavior in quasi-static compression/shear stress loading conditions. Materials and methodsFRC cages (n = 6) were manufactured with 2, 4, 6, 8 and 10 layers of glass fiber laminates and thermoset dimethacrylate resin matrix resulting in wall thickness from 0.70 to 2.1 mm. Control cage was a commercial PEEK cage (CeSpaceXP) implant with asymmetrical wall thickness of up 4.0 mm. Interior of the cage was filled with glass particles of the size 500–1250 μm simulating the bioactive glass which are used in FRC cranial implants. The FRC cages were quasi-statically loaded (compressive/shear stress) at a constant speed of 1 mm/min in the air. ResultsThe average yield strength force (YF) of the control PEEK cage was 3483.6 N (±134.3 N). The average YFs for tested FRC cage with 2, 4, 6, 8 and 10 layers of FRC fabric varied from 1336.5 N (±403.8 N) to 7675.0 N (±670.0 N), respectively. The average ultimate forces (UF) for tested FRC cages varied from 1535.8 N (±406.2 N) to 9975.0 N (±1492.4 N). With six layers of FRC fabric, YF of the FRC cage was comparable to the PEEK implants. ConclusionsIn this study, it was demonstrated that it is possible to manufacture a cervical interbody fusion device made of FRC and filled with bioactive glass with proper load bearing capacities. Because of physical properties of FRC-bioactive glass, the FRC cage might have some advances compared to the state-of-the-art cages, like faster bony union and smaller rate of subsidence, which will be studied in the future.

Clinical and Radiological Outcome in a Series of Patients Treated by Anterior Cervical Discectomy and Fusion: Retrospective Controlled Study With 2 Different Stand-Alone Cages.

Cervical spine balance and alignment targets after cervical spine surgery are poorly established in patients with cervical spine degenerative disease surgically treated by anterior cervical discectomy and fusion (ACDF). The objective of the study is to determine the correlation between radiological and clinical outcomes in patients surgically treated by ACDF with 2 different stand-alone cervical cages. Clinical outcomes were evaluated using visual analog scale (VAS), Neck Disability Index (NDI), Nurick Scale, and Japanese Orthopedic Association score for myelopathy. Radiological evaluation included cervical and segmental Cobb angles, cervical sagittal vertical axis (cSVA), T1 slope (T1s), C0-C2 angle, fusion rates, adjacent segment degeneration, and cage subsidence. A total of 80 patients were included with an average age of 53 years. There was a statistically significant improvement in both clinical and radiological evaluations. There was a statistical significant correlation between cervical pain on cervical VAS and cSVA. There was a significant correlation between postoperative T1s and cSVA, related to the improvement in cervical angles. There was no significant difference in rates of fusion, adjacent segment changes, or reoperation between both cervical cages, and there was a higher rate of subsidence in the Aleutian group. There were significant differences between both groups on postoperative NDI and VAS, but this difference is not maintained during follow-up. Cervical sagittal balance is directly related to clinical outcome in patients with cervical spine degenerative disease. Both cervical implants analyzed were comparable in clinical and radiological outcomes. There are important clinical and radiological parameters that should be taken into account for the analysis of the surgical outcome of patients treated by ACDF; this is one of the few studies that report the results with 2 different cervical cage designs.

P45. Titanium cervical cage subsidence: postoperative CT analysis defining incidence and associated risk factors

<h3>BACKGROUND CONTEXT</h3> Substantial variability in both the measurement and classification of subsidence limits the strength of conclusions that can be drawn from previous studies. <h3>PURPOSE</h3> The purpose of this study was to precisely characterize patterns of cervical cage subsidence utilizing computed tomography scans, determine risk factors for cervical cage subsidence and investigate the impact of subsidence on pseudarthrosis rates. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort study. <h3>METHODS</h3> We performed a retrospective review of a patients who underwent one- to three-levels of ACDF utilizing titanium interbodies with anterior plating between the years 2018 to 2020. Subsidence measurements were performed by two independent reviewers on CT scans obtained 6 months postoperatively. Subsidence was then classified as mild if subsidence into the inferior and superior endplate were both ≤2mm, moderate if the worst subsidence into the inferior or superior endplate was between 2 to 4mm, or severe if the worst subsidence into the inferior or superior endplate was ≥4mm. <h3>RESULTS</h3> A total of 51 patients (100 levels) were included in this study. A total of 48 levels demonstrated mild subsidence (<2mm), 38 demonstrated moderate subsidence (2–4mm), and 14 demonstrated severe subsidence (>4mm). Risk factors for severe subsidence included male gender, multilevel constructs, greater mean vertebral height loss, increased cage height, lower Taillard Index, and lower screw tip to vertebral body height ratio. Severe subsidence was not associated with an increased rate of pseudarthrosis. <h3>CONCLUSIONS</h3> Following ACDF with titanium cervical cages, subsidence is an anticipated postoperative occurrence and is not associated with an increased risk of pseudarthrosis. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

PEEK versus titanium-coated PEEK cervical cages: fusion rate.

Anterior cervical discectomy and fusion (ACDF) is one of the most commonly performed procedures for degenerative cervical disease. The evaluation of fusion status is still not fully standardized, and a variety of measurement methods are used. This study presents our own evaluation of fusion by comparing two types of implants. A total of 170 disc spaces were operated on in 104 patients using PEEK (polyetheretherketone) cages and titanium-coated (TC) PEEK cages. Patients were assigned to a specific implant using a randomisation table. Fusion status was evaluated based on functional radiographs and CT scans obtained at 12months post-surgery. Multivariate mixed-effects logistic regression models were performed to assess the association of type of implant with different fusion rates. At 12months post-surgery, CT scans were performed in 86 patients (a total of 144 disc spaces) and conventional radiographs were obtained in 102 (a total of 166 disc spaces). Complete fusion was demonstrated in 101 cases (71.1%), partial fusion in 43 cases (29.9%). There were no cases of absence of fusion. A total of 85 PEEK cages (59%) and 59 TC-PEEK cages (41%) were implanted. For PEEK cages, complete fusion was seen in 75 (88.2%) disc spaces, compared to 26 (44.1%) achieved with TC-PEEK cages. A significantly higher proportion of complete fusions (B = 15.58; P < 0.0001) after 12months was observed with PEEK implants compared to TC-PEEK implants. Complete fusion was noted at 12months post-surgery significantly more frequently with PEEK implants compared to TC-PEEK implants.

Cervical vertebral body replacement using a modern in situ expandable and angulable corpectomy cage system: early clinical and radiological outcome

Purpose Vertebral body replacement (VBR) cages are commonly implanted to reconstruct the cervical vertebrae in cases of tumour, trauma, spondylodiscitis, and degeneration. Expandable cages have been widely used for this purpose; however, the lacking congruence at the implant-bone interface and consequent implant displacement were considered as a serious drawback of such systems. Aim of this study is to evaluate the early clinical and radiological outcome of a modern in situ not only expandable but also angulable cervical corpectomy cage system. Methods A total of 42 patients who underwent a single or multilevel cervical VBR procedure were included and retrospectively evaluated in this single-centre case series. The neurological status was assessed using American Spinal Injury Association (ASIA) score. Complications were categorized into surgical (including implant-associated) and general medical. Radiographic parameters included regional angulation, segmental height, and coronal alignment. Results Mean age was 59.5 ± 20.6 years. The recorded ASIA score improved postoperatively by 10 points (p 0.0001). Surgical including implant-associated complication rates were 19.05%. Radiographic evaluation showed a height gain of 11.2 mm (p < 0.0001), lordotic correction of 7° (p < 0.0001), and coronal alignment of 3° (p < 0.0001). At the last follow-up, loss of angulation correction of 1.9° (p 0.0002), subsidence of 1.92 mm (p 0.0006), and fusion rates of 68.42% were observed. Conclusions The use of an in situ angulable and expandable cage system in cervical VBR seems to offer better results compared to conventional static or expandable cages regarding segmental height gain, lordotic correction, and clinical improvement as well as low complication and revision rates. Significant height gain in multilevel surgeries is associated with higher rates of implant-associated complications.

Safety and Feasibility of DTRAX Cervical Cages in the Atlantoaxial Joint for C1/2 Stabilization.

Pathological changes in the atlantoaxial joint often lead to instability, pain, and neurological deterioration. One treatment option is the surgical stabilization of the atlantoaxial joint. In other areas of the spine, fusion rates have been improved by the introduction of an interbody cage. Our aim was to use cervical interbody spacers, originally designed to augment fusion across subaxial posterior cervical facets, to optimize the conditions for atlantoaxial fusion. To evaluate the safety and efficacy of implanting cervical cages in the atlantoaxial joint for C1/2 stabilization. Our retrospective study evaluated patients who had undergone C1/2 cervical fusions by the Harms/Goel technique. This technique was modified by implanting a titanium cervical interbody spacer into the joint space. Mean overall pain, as measured by a 0 to 10 visual analog scale (VAS) and neurological outcomes were measured preoperatively and postoperatively. In addition, radiological outcomes were collected using follow-up imaging. Nine patients were included in this case series. The mean preoperative VAS for overall pain was 5.0 ± 4.0, which changed to a mean VAS of 2.0 ± 3.0 after an average follow-up period of 41.4 ± 20.4 (P = .043). All patients showed a bony fusion in our case series. None of the radiological imaging during follow-up showed screw loosening, hardware breakage, implant migration, or nonunion. The implantation of cervical titanium cages into the atlantoaxial joint in combination with posterior fixation appears to be a safe and effective method for achieving C1/2 fusion.