Successful Nonsurgical Management of a Traumatic Dens Fracture in a Cat with Clinical and Radiographic Resolution

ABSTRACT An adult domestic shorthair presented with obtundation, vestibular ataxia, head tilt, and visible evidence of facial injury following motor vehicle trauma. Plain radiographs and computed tomography imaging revealed a complete minimally displaced transverse fracture of the caudal aspect of the dens of the C2 vertebra and multiple minimally displaced cranial fractures. The dens fracture was managed with 8 wk of strict rest, followed by 4 wk of supervised activity at home. No external immobilization was performed. Neurological examinations at 8 days, 10 wk, and 9 mo following initial presentation were normal. Repeat radiographic and computed tomography examinations at 10 wk and 9 mo following the traumatic event demonstrated progressive and eventual complete osseous union of the fractured dens. To the authors’ knowledge, this is the first report of successful nonsurgical management of a traumatic dens fracture in an adult cat with documented radiographic and clinical resolution. This report suggests that nonsurgical management can be considered in such cats and that complete resolution with osseous union is feasible.

Use of halo fixation therapy for traumatic cranio-cervical instability in children: a systematic review

Purpose Traumatic cranio-cervical instability in childhood is rare and constitutes a challenge for the treating surgeon. The aim of therapy is to restore cervical stability without limiting the range of motion. The goal of this systematic review was to find out whether, over the last 10 years, halo fixation (HF) could still be considered a successful treatment option without major risks or complications. Methods We analyzed studies describing the use of HF in traumatic injuries of the cranio-cervical junction in children under the age of 17. Searches were performed in PubMed, MEDLINE and Embase databases for the years from 2010 to 2020. The general success rate, the success rate related to underlying pathologies, and complication rates were evaluated. Results The main indications for HF range from pre-surgical correction to postoperative fusion support. C2 is the most frequently injured vertebra in children. The overall success rate of HF was very high. Evaluation according to the underlying pathology showed that, except for atlanto-occipital dislocation, HF generates high fusion rates among different patient cohorts, mainly in C2 vertebra injuries and atlantoaxial rotatory subluxation. Only minor complications were reported, such as pin infections. Conclusion The current data show that, when used according to the appropriate indication, HF is an effective conservative treatment option for cranio-cervical instability, associated with only minor complications.

Transarticular Fixation Following Mobilization of “High-Riding” Vertebral Artery

BACKGROUND AND IMPORTANCE: The article identifies the feasibility of transarticular screw fixation after mobilizing the vertebral artery in cases where it is in a “high-riding” location. CLINICAL PRESENTATION: A 42-yr-old male patient had a 4-yr history of progressive quadriparesis. Investigations revealed severe basilar invagination. There was assimilation of atlas and C2-3 fusion. The vertebral artery was “high-riding” into the pedicle-facet of C2 vertebra on both sides. Vertebral artery loop was exposed and mobilized inferiorly on both sides after careful drilling of pedicular bone on the posterior aspect of the dome of the artery. C2 facetal bone on the anterior face of the vertebral artery dome was now available for screw insertion. The C1-2 facets and the articulation were directly in line, making transarticular screw fixation relatively straightforward. The wide bone space available permitted insertion of 2 screws in a transarticular fashion on both sides. The patient had satisfactory clinical improvement. Imaging after 22 mo showed bone fusion across the facets. CONCLUSION: Mobilization of the high-riding vertebral artery loop can help salvage the surgical procedure of lateral mass stabilization.

Single-Staged Transoral Intra-Lesional Excision of Aneurysmal Bone Cyst of Axis (C2) Vertebra and Temporary Stabilization of Upper Cervical Spine in an Adolescent: A Case Report

Aneurysmal bone cyst (ABC) infrequently occurs within the upper cervical vertebrae. Various therapeutic options have been reported in the literature. We would like to share our experience in managing a case of a 16-year-old girl diagnosed with ABC at the body of axis (C2) vertebra. Serious attention had to be given on the stability of the cervical spine following tumour resection, which can be affected by the mode of treatment chosen. Instability can have a detrimental effect on the cervical spine, in which case may necessitate further surgery. We performed a single-staged intra-lesional curettage via a transoral approach and temporary non-fusion posterior stabilization of C1 lateral mass screw and C2 pedicle screw. The implants were removed after six months once ossification of C2 has taken place to regain full motion of the neck. There was no evidence of recurrence or instability of the cervical spine three years following surgery.

Primary Ewing’s sarcoma of the C2 vertebra with progressive quadriparesis: Report of a rare case and review of the literature

Background: Ewing’s sarcoma is a malignant primitive neuroectodermal tumor (PNET) of childhood and adolescence. Primary Ewing’s sarcoma of the spine is uncommon, and even more rarely involves the C2 vertebra. Case Description: A 14-year-old patient was admitted with a history of chronic neck pain, which exacerbated after playing contact sports 3 weeks before presentation. On initial examination, he had pain radiating into the left upper extremity plus spasticity in all the four limbs. The cervical X-rays revealed a mixed sclerotic-lytic lesion involving the C2 vertebral body. The CT bony and soft-tissue windows documented predominant left-sided tumor invasion of the posterior elements, pedicles, and body of C2 along with extension into the spinal canal resulting in severe cord compression with peritumoral soft-tissue edema. The angiogram revealed a patent left vertebral artery entirely surrounded/encased by tumor. The PET-CT scan demonstrated no other spinal or systemic lesions. Due to his rapid neurological deterioration, the patient underwent an emergent biopsy of the tumor with posterior decompression and occipitocervical stabilization. The biopsy demonstrated a PNET (e.g., positive CD 99 MIC2 marker for Ewing’s sarcoma). Following subsequent chemotherapy and radiation, the patient rapidly improved over a period of 3 months. Conclusion: Primary Ewing’s sarcoma involving the C2 vertebra is exceedingly rare and warrants surgical decompression with pathological confirmation to provide additional multi-modal/multi-disciplinary adjunctive radiation/chemotherapy.