Comparison of clinical and radiological outcomes between modified Gallie graft fusion-wiring technique and posterior cervical screw constructs for Type II odontoid fractures

Posterior wiring with sublaminar polyester bands, titanium-peek fixation system for C2 fracture management: a 4-patient case series with a maximum of 18 months' follow-up

Background

C2 fractures can be classified differently when dens, pedicles or body are injured. With regards to the best management of Type-II Anderson-D'Alonzo fractures, Hangman's fractures of pedicles and C2 body fractures are more debatable. However, vertebral pedicle and/or articular screw and dorsal wiring are the most common surgical posterior approaches opted for. Compared to the screw technique, dorsal wiring provides certain benefits such as a lower risk of vertebral artery injury, no need for navigation, less lateral dissection of the paraspinal muscles, shorter surgery time and lower medical costs.

Case Description

Two patients with failed conservative treatment for Anderson-D'Alonzo Type-III fractures (Cases 1A and 1B), a patient suffering from a Type-II Hangman's fracture (Case 2) and a patient with failed conservative treatment for a C2 transversal body fracture (Case 3) underwent surgery at the Neurosurgery Division of the University Hospital of Modena (Italy) between July 2020 and September 2021. All patients were treated with posterior wiring with 5 mm Polyester bands, titanium-peek fixation system (Jazz-Lock system MediNext®-Implanet) inserted through the C1 posterior arch and either the C2 or C3 laminae. A fracture diastasis reduction was observed ranging between 4.5 and 1 mm. No intraoperative and post-operative complications were encountered. The duration of the period of hospitalisation ranged between 5 and 12 days. All patients who had worked prior to the traumatic event were able to return to work 18 months following surgery.

Conclusions

In reducing C2 fractures, a sublaminar fixation with polyester bands and a titanium-peek fixation system can be proposed for fragile and elderly patients.

Regional variations in C1-C2 bone density on quantitated computed tomography and clinical implications

Background

Our elderly population is growing and the number of spine fractures in the elderly is also growing. The elderly population in general may be considered as poor surgical candidates experience a high rate of fractures at C1 and C2 compared with the general population. Nonoperative management of upper cervical fractures is not benign as there is a high nonunion rate for both C1 and C2 fractures in the elderly, and orthosis compliance is often suboptimal, or complicated by skin breakdown. The optimal technique for upper cervical stabilization in the elderly may be different than in younger populations as the bone quality is inferior in the elderly. The objective of this basic science study is to determine whether the bone mineral density (BMD) of C1 and C2 vary by region, and if this is a gender difference in this elderly age group.

Methods

Twenty cadaveric spines from 45 to 83 years of age were used to obtain BMD using quantitated computed tomography (QCT). BMD was measured using a QCT. For C1, 8 regions were determined: anterior tubercle, bilateral anterior and medial lateral masses, bilateral posterior arches, and posterior tubercle. For C2, 7 regional BMDs were determined: top of odontoid, base of odontoid-body interface, mid body, bilateral lateral masses, anterior inferior body near the discs space, and the C2 spinous process.

Results

The BMD was greatest at the C1 anterior tubercle (564.4±175.8 mg/cm³) and C1 posterior ring (420.8±110.2 mg/cm³), and least at the anterior and medial lateral masses (262.8±59.5 mg/cm³, 316.9±72.6 mg/cm³). At C2 QCT BMD was greatest at the top of the dens (400.6±107.9 mg/cm³) decreasing down through the odontoid-C2 body junction (267.8±103.5 mg/cm³) and least in the mid C2 body 249.1±68.8 mg/cm³). The posterior arch of C1 and the spinous process of C2 had higher BMD's 420.8±110.2 mg/cm³ and 284.1±93.0 mg/cm³, respectively. A high correlation was observed between the BMD at the interface of the dens-vertebral body with the vertebral body with a Pearson correlation coefficient of 0.86. The BMD of the top of dens was significantly higher (p<.05) than all the regions in C2.

Conclusions

Regional and segmental BMD variations at C1 and C2 have clinical implications for surgical constructs in the elderly population. Given the higher BMDs of the C1 and C2 spinous process and posterior arches, consideration should be given to incorporate these areas using various C1-C2 wiring techniques. In the elderly, lateral masses particularly at C1 with lower BMD may result in potential screw loosening and nonunion in this age group. Old-school wiring techniques have a track record of efficacy and safety with less blood loss, reduced operative time, reduced X-ray exposure, and should be considered in the elderly as a primary stabilization technique or a belt-over suspenders approach based on regional variations in BMD in the elderly.

Does isolated atlantoaxial fusion result in better clinical outcome compared to occipitocervical fusion?

BACKGROUND

The C0 to C2 region is the keystone for range of motion in the upper cervical spine. Posterior procedures usually include a fusion of at least one segment. Atlantoaxial fusion (AAF) only inhibits any motion in the C1/C2 segment whereas occipitocervical fusion (OCF) additionally interferes with the C0/C1 segment. The purpose of our study was to investigate clinical outcome of patients that underwent OCF or AAF for upper cervical spine injuries.

METHODS

Over a 5-year period (2010-2015), consecutive patients with upper cervical spine disorders were retrospectively identified as having been treated with OCF or AAF. The Numeric Pain Rating Scale (NPRS) and the Neck Disability Index (NDI) were used to evaluate postoperative neck pain and health restrictions. Demographics, follow-up, and clinical outcome parameters were evaluated. Infection, hematoma, screw malpositioning, and deaths were used as complication variables. Follow-up was at least 6 months postoperatively.

RESULTS

Ninety-six patients (male = 42, female = 54) underwent stabilization of the upper cervical spine. OCF was performed in 44 patients (45.8%), and 52 patients (54.2%) were treated with AAF. Patients with OCF were diagnosed with more comorbidities (p = 0.01). Follow-up was shorter in the OCF group compared to the AAF group (6.3 months and 14.3 months; p = 0.01). No differences were found related to infection (OCF 4.5%; AAF 7.7%) and revision rate (OCF 13.6%; AAF 17.3%; p > 0.05). Regarding bother and disability, no differences were discovered utilizing the NDI score (AAF 21.4%; OCF 37.4%; p > 0.05). A reduction of disability measured by the NDI was observed with greater follow-up for all patients (p = 0.01).

CONCLUSION

Theoretically, AAF provides greater range of motion by preserving the C0/C1 motion segment resulting in less disability. The current study did not show any significant differences regarding clinical outcome measured by the NDI compared to OCF. No differences were found regarding complication and infection rates in both groups. Both techniques provide a stable treatment with comparable clinical outcome.