Occipital plate-assisted posterior reduction for tumor-related severe atlantoaxial dislocation: a single-case surgical technique

Introduction

The atlantoaxial complex contributes substantially to cervical rotation and protects the cervicomedullary junction. Tumor involvement of the atlas, axis, or adjacent craniovertebral structures may cause osteolytic destruction, pathological fracture, spinal instability, high cervical neural compression, pain, and progressive neurological deficits. When neurological deterioration occurs at this level, limb function, respiratory safety, and bulbar function may be threatened; therefore, restoration of stability and alignment can become urgent when conservative or oncological therapy alone is insufficient (1).

Most established reduction strategies for atlantoaxial dislocation were developed for congenital, inflammatory, traumatic, rotatory, or degenerative disorders. Chao Wang, Shenglin Wang, and colleagues described transoral anterior release followed by posterior fixation, quantified the reciprocal relationship between occipitoaxial and subaxial alignment, evaluated C2 pedicle versus laminar screw corridors, reported cable-strengthened C2 pedicle fixation, and summarized surgical outcomes in a large os odontoideum series (2-6). These principles remain valuable, but their direct application to tumor-related dislocation requires caution because the mechanical substrate is different (7-10).

In tumor-related atlantoaxial dislocation, the axis is frequently weakened by metastasis, multiple myeloma, plasmacytoma, or primary bone tumor. Severe anterior translation of the atlas may move the C1 lateral mass anterior to the axis body, making the C1 entry point inaccessible. Tumor destruction may compromise the C2 pedicle, pars, lamina, or vertebral body, thereby limiting the reliability of C2-based fixation. Forceful C1–C2 manipulation under these conditions may increase the risk of screw pullout, fracture propagation, vertebral artery injury, uncontrolled displacement, or neurological deterioration. Even in broader non-oncological C1–C2 screw-rod construct literature, clinically significant screw malposition and vertebral artery injury have been reported at pooled rates of 2.4% and 2.0%, respectively (11), emphasizing why tumor-destroyed anchors require particular caution.

The surgical objective is therefore not merely anatomical reduction, but safe redistribution of the reduction force. This article describes an open posterior occipital plate-assisted reduction method in which the occipital plate functions as the proximal reduction handle and the subaxial cervical spine functions as the distal fixation base. The technique is primarily a palliative/stabilizing oncological procedure rather than a curative tumor resection. Figures 1,2 demonstrate the radiographic correction and key intraoperative construct. We present this article in accordance with the SUPER reporting checklist (available at https://jss.amegroups.com/article/view/10.21037/jss-2026-0162/rc).

Figure 1 Representative preoperative and postoperative CT images. (A) Preoperative sagittal CT showing osteolytic destruction of the C2 vertebral body and odontoid process, marked atlantoaxial displacement, and spinal canal compromise. (B) Postoperative sagittal CT showing near-anatomical reduction and relief of canal compromise. (C) Preoperative coronal CT showing C2 destruction with lateral deviation of the odontoid process and atlantoaxial dislocation. (D) Postoperative coronal CT showing satisfactory reduction, a centered odontoid process, and anatomical correction of the dislocation. CT, computed tomography.

Figure 2 Operative details. (A) Intraoperative photograph showing the unilateral rod-assisted reduction construct and the occipital plate/rod interface. (B) Post-reduction lateral fluoroscopy demonstrating correction of atlantoaxial alignment and provisional occipitocervical fixation.

Preoperative preparations and requirements

Surgical setting, equipment, and personnel

The procedure should be performed in a tertiary referral hospital with experience in upper cervical reconstruction and spinal oncology. It requires a fully equipped operating room suitable for prone posterior cervical surgery, controlled airway management, intraoperative fluoroscopy, spinal neuromonitoring when available, and immediate access to blood products and postoperative intensive monitoring when clinically indicated.

The necessary equipment includes a radiolucent operating table, a Mayfield three-pin head holder, lateral and anteroposterior fluoroscopy, standard posterior cervical decompression instruments, hemostatic materials, a high-speed burr, a posterior occipitocervical screw-rod system with an occipital plate, rods, locking caps, occipital screws, lateral mass or pedicle screws for distal fixation, and bone graft materials. No dedicated proprietary software, customized implant, or altered implant material is required for the reduction maneuver itself.

The operating team should include a senior spine surgeon experienced in posterior cervical/occipitocervical fixation and spinal tumor surgery, a trained assistant familiar with reduction maneuvers, an anesthesiology team capable of managing an unstable cervical spine during intubation and prone positioning, scrub nurses familiar with occipitocervical instrumentation, radiology personnel for repeated fluoroscopic checks, and neuromonitoring personnel when somatosensory and motor evoked potentials are used. The first application of the technique should be undertaken only after preoperative imaging review, reduction planning, and team rehearsal because small variations in rod contouring or plate offset may change the final occipitocervical alignment.

Patient selection

The technique is intended for severe but reducible atlantoaxial dislocation secondary to an axis tumor, spinal metastasis, multiple myeloma, plasmacytoma, or another osteolytic lesion (Table 1). It is particularly useful when anterior atlas displacement prevents safe C1 lateral mass screw placement or when C2 fixation is unreliable because of tumor destruction. It may also be considered when posterior decompression, tissue sampling, reduction, stabilization, and fusion can be performed in the same session.

The principal prerequisites are adequate occipital bone stock, reliable distal cervical fixation points, and radiographic or intraoperative evidence that the dislocation remains reducible. Relative contraindications include completely fixed dislocation caused by ankylosis or rigid bony obstruction, extensive destruction of both proximal and distal fixation bases, severe systemic deterioration that precludes prone posterior surgery, uncontrolled infection or coagulopathy, and bone quality insufficient for stable screw purchase. Patient-level factors to be documented include age, sex, pain distribution, myelopathic or radicular signs, cranial nerve/bulbar symptoms, respiratory and swallowing status, tumor type or suspected histology, systemic oncological stage, prior radiotherapy or chemotherapy, comorbidities, anticoagulation status, and previous cervical surgery.

Illustrative case

A 58-year-old woman was admitted with a 1-year history of neck pain and limited mobility. Her limb muscle strength and sensation were normal, with no neurological deficits. The pain score was 7 on the visual analogue scale (VAS). Imaging revealed severe tumor-related atlantoaxial dislocation associated with osteolytic destruction and pathological fracture of C2, with marked spinal canal compromise.

Ethics and consent

Institutional review board approval was waived by the Ethics Committee of Peking University Third Hospital because this was a single-patient surgical technique report without prospective intervention or experimental treatment. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient for publication of this surgical technique article and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Imaging assessment

Preoperative computed tomography (CT) should evaluate the extent of osteolysis, pathological fracture, residual occipital bone stock, and feasibility of distal cervical fixation. Particular attention should be paid to the occipital squama, C2 pedicle/pars/lamina, C3–C5 lateral masses, and any vertebrae that may be compromised by tumor. Dynamic or positional radiographs may be considered only when they can be obtained safely. Because tumor progression and adjuvant radiotherapy can weaken bone over time, the distal fixation range should be selected for durable stability rather than minimum invasiveness alone (12-17). Recent data on craniocervical junction metastases reinforce the value of rigid occipitocervical fixation within a multidisciplinary oncology pathway, although that experience does not address the specific reduction problem created by severely destroyed C1–C2 anchors (18).

Magnetic resonance imaging is required to define epidural tumor extension, cord or medullary compression, soft-tissue involvement, marrow infiltration, and the relationship between the lesion and neural elements. Computed tomography angiography (CTA) is recommended when the tumor distorts C1–C2 anatomy, when osteolysis may expose the vertebral artery, or when prior imaging suggests a high-riding, anomalous, encased, or displaced vertebral artery. High-riding vertebral artery variants are commonly screened using C2 isthmus height and internal height thresholds, and reported prevalence varies across populations; therefore, CTA findings should be reviewed before deciding whether C1/C2 screws, C2 pars/laminar alternatives, or subaxial-only distal anchors are safest (19).

Oncological and anesthetic preparation

The surgical plan should be integrated with established principles of spinal oncology. Neurological status, oncological radiosensitivity, mechanical instability, systemic condition, and expected survival should be considered together. The spinal instability neoplastic score (SINS) and the neurological, oncological, mechanical, and systemic (NOMS) framework are useful because they distinguish mechanical instability from tumor control alone (20-23). In a mechanically unstable axis tumor with severe dislocation, radiotherapy alone cannot restore immediate alignment or stability.

General anesthesia should be planned with attention to awake or fiberoptic intubation when needed, maintenance of cervical alignment during airway management, cervical instability during turning and prone positioning, neuromonitoring availability, potential epidural or venous plexus bleeding, and the need for tissue diagnosis. Preoperative preparation should include blood typing and cross-matching, correction of coagulopathy, urinary catheterization when prolonged surgery is expected, skin preparation from the occiput to the upper thoracic region, and availability of postoperative collar immobilization.

Operative setup and safety controls

Surgical approach, key landmarks, and adjacent structures

A posterior midline open approach is used. The incision is planned according to the intended fixation range and usually extends from the external occipital protuberance or suboccipital region to the lowest planned distal cervical fixation level. The surgeon stands at the side that permits optimal fluoroscopic access and construct assembly, whereas the assistant maintains exposure and protects the soft tissues. Subperiosteal dissection exposes the occipital squama, posterior arch region when needed, and selected distal lateral masses or pedicles. Excessive dissection around tumor-involved C1–C2 should be avoided to reduce bleeding and prevent destabilization of residual bone.

Essential landmarks include the external occipital protuberance, midline occipital keel, occipital squama for screw placement, foramen magnum margin, C2 posterior elements if preserved, C3–C5 lateral masses, facet joints, vertebral artery-related osseous corridors, epidural tumor, dura, and nerve roots. The vertebral artery may be displaced, encased, or exposed by osteolysis; therefore, preoperative CTA should be reviewed before selecting C1/C2 exposure, decompression extent, or distal fixation paths.

Intraoperative monitoring and safety controls

Lateral and anteroposterior fluoroscopy should be obtained after positioning, after distal fixation, during plate compression, and after final tightening. Somatosensory and motor evoked potential monitoring is recommended when available, particularly in patients with preoperative myelopathy or severe canal compromise. If neuromonitoring deteriorates, reduction should be stopped, the construct should be released if needed, blood pressure and anesthetic factors should be corrected, and decompression should be reassessed before repeating a staged maneuver.

Step-by-step description

Step 1: Positioning and baseline alignment assessment

After induction of general anesthesia, the head is secured in a Mayfield head holder and the patient is carefully positioned prone. The head and neck are maintained in neutral or slight corrective alignment. Excessive flexion, extension, rotation, or sustained traction should be avoided. Baseline lateral and anteroposterior fluoroscopy is obtained after positioning to document occipitocervical and atlantoaxial alignment. The complete operative workflow and safety checkpoints are summarized in Table 2.

Step 2: Posterior exposure and decompression

A posterior midline incision is made according to the planned fixation range. The occipital squama and selected distal cervical levels are exposed. Dissection around the tumor-involved C1–C2 region should be limited to what is necessary for decompression, tissue diagnosis, and safe instrumentation, thereby reducing venous bleeding and unnecessary tissue disruption.

Posterior decompression, laminectomy, epidural tumor removal, or limited lesion curettage is performed according to the compression pattern. In selected patients, reduction itself contributes to decompression by restoring canal diameter. When neural elements are critically compressed, sufficient decompressive space should be created before the reduction maneuver. Tissue specimens should be sent for frozen section and definitive pathology when tumor histology is uncertain.

Step 3: Distal cervical fixation

Reliable distal fixation is established first. Lateral mass screws, pedicle screws, or other posterior cervical fixation options are selected according to local anatomy, tumor involvement, and bone quality. If C2 is destroyed or biomechanically unreliable, fixation should be extended to C3, C4, C5, or lower. These anchors provide the counterforce base for reduction. Screw trajectory and purchase are verified by tactile feedback and fluoroscopy.

Step 4: Rod contouring and occipital plate offset

The rod is precontoured to the intended occipitocervical alignment before reduction because it functions as the alignment template. Excessive occipitocervical flexion should be avoided to reduce the risk of dysphagia, dyspnea, and horizontal-gaze disturbance; excessive extension should also be avoided because it may compromise neural space or create compensatory malalignment (24-27).

The occipital plate is positioned on the occipital squama according to standard fixation principles. The distal cervical screws are connected to the rod and locked. The occipital plate is then connected to the proximal rod while a deliberate step-off is maintained between the proximal plate holes and the occipital surface. The offset should be conservative and controlled; in this patient, an approximately 1-cm offset was selected as the maximum planned reduction reserve rather than as a validated biomechanical threshold (Table 3). This value should not be generalized as a fixed rule; a smaller offset should be selected whenever adequate reduction can be achieved safely, and future cadaveric or finite element work is needed to define construct-specific limits.

Step 5: Occipital plate-assisted reduction

The proximal part of the occipital plate is pressed down until it contacts the occipital surface. While the plate is held in the reduced position, the occipital holes are drilled and occipital screws are inserted. Release of down-pressure allows the plate and skull-occiput complex to settle into the precontoured rod-defined alignment, completing indirect posterior reduction of the atlantoaxial relationship.

Fluoroscopy is used to assess the atlantoaxial relationship, canal diameter, occipitocervical angle, and implant position. If satisfactory near-anatomical reduction is achieved, the contralateral construct can be placed in situ. If residual anterior translation remains and reduction is still judged safe, a staged offset-compression maneuver may be performed on the opposite side. The tumor-destroyed atlas or axis should not be used as the principal reduction handle.

Step 6: Final fixation, fusion, and illustrative application

After satisfactory reduction, all locking caps are tightened sequentially and final fluoroscopic images are obtained. Bone grafting is performed across the intended fusion levels when appropriate. Graft selection should be individualized according to tumor biology, bone quality, planned radiotherapy, systemic treatment, and expected survival. A drain is placed and the wound is closed in layers. The main procedural sequence and intraoperative checkpoints are summarized in Table 2; the maneuver-specific safeguards are then detailed in Table 3.

In the illustrative patient, the working diagnosis was a C2 malignant tumor or metastatic lesion with multifocal cervical involvement, osteolytic axis destruction, pathological fracture, and atlantoaxial dislocation. The indication for surgery was mechanical instability at C1–C2 with risk of neurological deterioration, combined with the need for tissue diagnosis, decompression, reduction, and durable occipitocervical stabilization. Preoperative CTA was reviewed specifically to assess vertebral artery dominance, high-riding or anomalous C2 course, and possible exposure or encasement by the osteolytic lesion. Because tumor destruction and displacement did not provide a reliable tumor-free C1/C2 screw corridor for reduction, the operative plan deliberately avoided C1/C2 screw-based reduction and used occipital screws with C3–C5 lateral mass fixation; the distal lateral mass screw paths were planned outside the transverse foramina, and no vertebral artery-related intraoperative complication occurred.

After exposure of the occipital squama and posterior cervical elements, bilateral C3–C5 lateral mass screw channels were prepared and 14-mm lateral mass screws were inserted. A unilateral C3–C5 screw construct was first connected to a precontoured rod and occipital plate. An approximately 1-cm plate-to-skull offset was deliberately maintained as the maximum planned reduction reserve for this patient. After the distal cervical locking caps were secured, the occipital screw holes were drilled, the occipital plate was compressed toward the skull, and occipital screws were inserted. As traction was relaxed and the construct settled into the rod-defined alignment, the atlantoaxial dislocation was reduced. C2 decompression and tissue sampling were performed, and intraoperative frozen assessment was suggestive of a plasma-cell neoplasm. Pathological work-up was therefore interpreted conservatively as a plasma-cell neoplasm; final classification as solitary plasmacytoma, solitary plasmacytoma with minimal marrow involvement, or multiple myeloma should depend on systemic staging, bone marrow assessment, serum/urine monoclonal protein studies, and imaging according to International Myeloma Working Group criteria (28). Immediate postoperative CT and fluoroscopy demonstrated restoration of atlantoaxial alignment, centering of the odontoid process, and relief of canal compromise; the quantitative radiographic changes are summarized in Table 4 (Figures 1,2).

Postoperative considerations and tasks

Technical and clinical evaluation

Technical success is defined as stable occipitocervical fixation, anatomical or near-anatomical improvement in the atlantoaxial relationship, improved odontoid centering, absence of new canal compromise, appropriate O-C2 alignment, and no implant-related complication on immediate postoperative imaging. Technical failure includes inability to achieve safe reduction, occipital or distal screw pullout, implant malposition requiring revision, new neurological deficit attributable to correction, or persistent clinically significant instability. Clinical evaluation should include pain, neurological function, swallowing, respiratory status, ambulation, wound healing, oncological diagnosis, and tolerance of adjuvant therapy.

From the patient perspective, the most relevant outcomes are relief of mechanical neck pain, preservation or recovery of limb function, absence of dysphagia or dyspnea, maintenance of horizontal gaze, and ability to proceed to definitive oncological treatment. These outcomes should be prospectively collected in future series.

Postoperative monitoring

Postoperative CT should confirm the position of occipital and cervical screws, reduction quality, odontoid centering, canal decompression, and absence of implant-related complications. Lateral radiography or CT should be used to assess the atlantodental interval, C1–C2 translation, O-C2 angle, posterior occipitocervical angle, and subaxial compensation when available. Neurological function, swallowing, respiratory status, wound drainage, and neck alignment should be monitored closely during the early postoperative period. Dysphagia or dyspnea should prompt reassessment of O-C2 alignment and retropharyngeal soft-tissue status. The cervical collar protocol should be individualized according to bone quality, fixation length, tumor burden, and anticipated adjuvant therapy.

Complication prevention and management

Complications requiring specific attention include dysphagia, dyspnea, respiratory compromise, wound problems, cerebrospinal fluid leakage, infection, implant loosening, occipital screw pullout, distal junctional failure, nonunion, local tumor progression, and neurological deterioration. Prevention depends on appropriate O-C2 alignment, adequate decompression before correction when necessary, durable distal fixation, meticulous hemostasis, early recognition of swallowing or airway symptoms, and timely multidisciplinary oncological treatment. Suspected implant failure or recurrent instability should be evaluated with CT and managed by external immobilization, extension of fixation, revision instrumentation, or oncological treatment according to the mechanism of failure.

Follow-up and adjuvant treatment

The definitive pathological diagnosis should guide adjuvant treatment. Postoperative radiotherapy, chemotherapy, targeted therapy, immunotherapy, anti-myeloma therapy, or bone-modifying agents should be discussed through a multidisciplinary oncological pathway. In the illustrative patient, referral to hematology and radiation oncology was appropriate after histological confirmation of a plasma-cell neoplasm; local radiotherapy should be considered for residual/local disease control, whereas systemic anti-myeloma therapy should be determined by marrow involvement, monoclonal protein studies, whole-body imaging, and systemic staging. At early postoperative assessment, postoperative CT confirmed maintained reduction, and no procedure-related vertebral artery injury, implant failure, dysphagia, dyspnea, or new neurological deterioration occurred. Only early postoperative follow-up was available; consequently, longer-term fusion, local tumor control, systemic progression, survival, and reoperation could not be assessed. This limited follow-up is an important limitation of the present single-case technical note. A practical follow-up schedule is clinical and radiographic assessment before discharge, at approximately 1 month, 3 months, 6 months, and 12 months after surgery, and every 6–12 months thereafter when survival and tumor course permit. Oncology-driven imaging may be required every 2–3 months during the first year for aggressive disease. Follow-up should document fusion status, implant failure, local tumor control, pain, neurological function, dysphagia, survival, and need for revision surgery. Compared with conventional occipitocervical fixation performed after traction or direct alignment correction, this technique requires closer early radiographic assessment of the occipital plate-screw interface and the alignment achieved by the offset-compression maneuver.

Tips and pearls

Quality and consistency

Quality control begins before incision. The surgeon should define the target occipitocervical alignment, distal fixation range, maximum acceptable plate-to-skull offset, decompression sequence, CTA-based vertebral artery risk controls, and bailout strategy. The rod must be contoured before reduction because it defines the final alignment. The step-off should be planned conservatively, treated as a reduction reserve rather than a target, and reassessed under fluoroscopy before plate compression. Reduction should be staged rather than abrupt, with repeated assessment of the atlantodental interval, C1–C2 translation, odontoid centering, canal diameter, and O-C2 alignment.

Safety

The central safety principle is to avoid using destroyed C1 or C2 bone as the primary reduction anchor. Reduction force should be applied through preserved occipital and subaxial structures. If screw purchase is poor, if the occipital plate fails to seat safely, if neuromonitoring signals deteriorate, or if fluoroscopy shows excessive correction or malalignment, the maneuver should be stopped. Possible intraoperative complications include epidural bleeding, vertebral artery injury, dural injury, neural compression during correction, screw pullout, occipital fracture, rod/plate mismatch, and inadequate reduction. Management may require additional decompression, hemostatic control, revised screw trajectory, extension of distal fixation, reduction of the plate offset, staged bilateral correction, or conversion to stabilization without further reduction.

Visualization

The key information is visualized in Figures 1,2. Figure 1 demonstrates preoperative C2 osteolysis, atlantoaxial displacement, postoperative odontoid centering, and restoration of canal diameter on sagittal and coronal CT. Figure 2 demonstrates the intraoperative unilateral rod-assisted reduction construct and post-reduction fluoroscopic alignment.

Discussion

Key technical rationale

Severe tumor-related atlantoaxial dislocation should not be viewed simply as another form of difficult or irreducible atlantoaxial dislocation. In congenital or inflammatory disorders, the atlas and axis may be dysplastic or malaligned, but they often remain structurally available for release, traction, and screw-based reduction. In contrast, tumor-related dislocation is commonly caused by pathological fracture and collapse of C2; the vertebra that would normally function as a reduction target may be the weakest portion of the construct.

This difference explains the rationale for avoiding forceful C1/C2 instrumentation. When the atlas translates anteriorly beyond the axis body, the C1 lateral mass entry point may be hidden or unsafe. When the axis is destroyed, C2 pedicle, pars, or laminar screws may be biomechanically unreliable. The proposed technique shifts the reduction force away from the diseased segment and toward preserved cranial and subaxial anchors.

Relationship to prior reduction strategies

The reduction philosophy of Chao Wang, Shenglin Wang, and colleagues emphasized release when necessary, careful restoration of craniovertebral alignment, recognition of vascular and osseous constraints, and fixation selection according to complex anatomy (2-6). The present technique extends these principles into oncological instability by asking a different mechanical question: if C1 and C2 cannot safely accept reduction force, where should that force be applied?

Standard occipitocervical fixation has long been used for craniovertebral junction tumors and upper cervical metastases. A recent series of metastatic craniocervical junction tumors treated with occipitocervical fusion using cervical pedicle screws reported pain relief, improvement in performance status in most patients, and no intraoperative complications related to pedicle screws (18). That experience supports the stabilizing value of rigid posterior constructs in oncological disease, but it differs from the present scenario because the main technical problem here was not only fixation but also how to achieve reduction when the C1–C2 complex could not safely accept reduction force. In many reports, the occipital plate functions mainly as a fixation endpoint after traction, decompression, or alignment correction. The current method emphasizes its active role as a controlled reduction handle.

Biomechanical interpretation

The maneuver is analogous to posterior reduction of spondylolisthesis, where the rod defines the intended alignment and the screw-rod interface translates the displaced segment toward that alignment (29). Classical C1–C2 screw-rod fixation also demonstrates the ability of posterior instrumentation to achieve reduction (30,31). The critical distinction in the present oncological setting is that the reduction handle is deliberately moved away from the pathological vertebra.

By creating a plate-to-skull offset, the surgeon stores a controlled reduction reserve. Compressing the plate to the occipital surface and fixing it with screws transforms the offset into a posteriorly directed alignment force. The precontoured rod constrains the final position, and the distal cervical construct provides counterforce. Because force is applied through the skull-occiput complex rather than through destroyed C1 or C2 bone, the risk of local implant failure or fracture propagation may be reduced. The maneuver should nevertheless be considered experimental: the approximate 1-cm offset used in this patient represented the maximum planned reduction reserve, and the relationship among offset distance, occipital screw stress, rod contour, bone density, and reduction force remains unquantified.

Impact, cost, and implementation

The practical impact of this technique is that it offers a posterior-only option for patients in whom direct C1/C2 reduction anchors are unsafe. Because the maneuver uses standard occipitocervical instrumentation and does not require a proprietary reduction device, its direct equipment cost is expected to be similar to that of conventional occipitocervical fixation with comparable fixation length. Potential economic advantages include avoidance of staged anterior release, prolonged traction, or revision for failed C1/C2 purchase; potential cost increases include longer distal fixation, additional fluoroscopic checks, neuromonitoring, and greater need for senior surgical expertise. Formal cost-effectiveness analysis has not yet been performed.

Strengths, limitations, and future directions

The advantages of this technique include posterior-only execution, use of standard occipitocervical instrumentation, avoidance of sustained traction, reduced need for extensive atlantoaxial joint release, and avoidance of direct manipulation of tumor-involved C1/C2. These features may improve reproducibility in centers familiar with posterior cervical fixation.

The limitations are important. This article is a surgical technique with a single illustrative case rather than a comparative clinical study. The technique should not be generalized to completely rigid dislocation, absent proximal or distal fixation anchors, uncontrolled systemic disease, or situations in which operative risk exceeds likely benefit. The preliminary radiographic and clinical measurements in Table 4 describe only one patient and cannot establish efficacy, complication rates, reduction durability, or oncological benefit. Quantitative evaluation of the atlantodental interval, C1–C2 translation, O-C2 angle, canal diameter, neurological function, fusion status, local tumor control, implant failure, dysphagia, and survival is needed in future studies.

A multicenter case series focusing on tumor-related atlantoaxial dislocation would be the most clinically useful next step. Patients could be stratified by reducibility, extent of C2 destruction, use of C1/C2 screws, fixation range, and adjuvant treatment. Finite element analysis could compare C1/C2-based pulling, traction-assisted reduction, and occipital plate-assisted reduction to quantify stress distribution across occipital screws, rods, distal cervical screws, residual C2 bone, and the vertebral artery-adjacent region.

Conclusions

Occipital plate-assisted reduction is a posterior-only strategy that was applied in one selected patient with severe but reducible atlantoaxial dislocation secondary to an axis tumor. Its defining principle is to use the occipital plate as the active proximal reduction handle and the subaxial cervical spine as the distal fixation base, rather than attempting to lift or instrument the tumor-involved atlas or axis. In this illustrative case, a planned plate-to-skull step-off helped achieve near-anatomical realignment while avoiding sustained traction, extensive atlantoaxial release, and high-risk C1/C2 reduction screws. The technique remains investigational, and larger clinical series and biomechanical studies are required to validate reduction durability, safety, offset limits, and indications.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the SUPER reporting checklist. Available at https://jss.amegroups.com/article/view/10.21037/jss-2026-0162/rc

Peer Review File: Available at https://jss.amegroups.com/article/view/10.21037/jss-2026-0162/prf

Funding: This work was supported by the Beijing Natural Science Foundation(No. L241068), the 2025 Hainan Provincial Health Science and Technology Innovation Joint Project (No. WSJK2025QN123), and the 2024 Hainan Provincial Higher Education Scientific Research Project (No. Hnky2024-28).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jss.amegroups.com/article/view/10.21037/jss-2026-0162/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Institutional review board approval was waived by the Ethics Committee of Peking University Third Hospital because this article is a single-patient surgical technique report without prospective intervention or experimental treatment. All procedures performed in this study were in accordance with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient for publication of this surgical technique article and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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