The contemporary treatment of odontoid injuries

Worsening ambulation in elderly patients with cervical odontoid fractures: A nationwide multicenter study in Japan

BACKGROUND

Despite the increasing prevalence of cervical odontoid fractures in older adults, the treatment strategy is controversial. The objectives of the current study are to investigate the prognosis and complications of cervical odontoid fractures in elderly patients and to identify factors associated with worsening of ambulation after 6 months.

METHODS

This multicenter, retrospective study included 167 patients aged 65 years or older with odontoid fractures. Patient demographic and treatment data were investigated and compared according to the treatment strategy. To determine associations with worsening ambulation after 6 months, we focused on the treatment strategies (nonsurgical treatment [collar immobilization or halo vest], conversion to surgery, or initial surgery) and patients' background.

RESULTS

Patients who received nonsurgical treatment were significantly older, and patients who underwent surgery had more Anderson-D'Alonzo type 2 fractures. Of the patients initially treated nonsurgically, 26% later underwent surgery. Numbers of complications, including death, and degrees of ambulation after 6 months did not differ significantly among treatment strategies. Patients who had worsened ambulation after 6 months were significantly more likely to be older than 80 years, to have needed assistance with walking before injury, and to have cerebrovascular disease. Multivariable analysis showed that a score of ≥2 on the 5-item modified frailty index (mFI-5) was significantly associated with worsening ambulation.

CONCLUSIONS

Preinjury mFI-5 scores of ≥2 were significantly associated with worsening ambulation 6 months after treatment of cervical odontoid fractures in older adults.

Combined Anterior Odontoid Screw Fixation and C1-C2 Jefferson Fracture Anterior Fixation: A Step-by-Step Technical Note

BACKGROUND

Combined triple atlas (C1)-axis (C2) fixation has been described in previous literature as a safe, effective, and minimally invasive procedure for complex atlas and odontoid fractures that allows for a greater range of motion compared with posterior approaches and atlanto-occipital fusion. However, it is rarely performed due to the occipital-cervical diastasis resulting from often-fractured C1 joint masses. No evidence-based consensus has been reached regarding the treatment of complex atlantoaxial fractures, and the choice of surgical strategy is based only on clinical experience.

METHODS

We report the combined triple C1-C2 fixation technique with manual reduction of the joint masses during patient positioning on the operating table, which allowed for effective stabilization during a single surgical session. We describe our experience in the management of a 75-year-old patient presenting with an acute complex type II fracture of C1, which also involved 1 lateral mass, combined with a type II odontoid fracture and occipital-cervical diastasis.

RESULTS

We provide a step-by-step guide for combined triple C1-C2 anterior fixation with manual fracture reduction and describe the clinical case of an acute complex type II fracture of C1, which also involved 1 lateral mass, combined with a type II odontoid fracture and occipital-cervical diastasis.

CONCLUSIONS

Combined triple C1-C2 fixation represents a safe and efficient minimally invasive anterior approach for complex type II fractures of C1 with type II odontoid fractures. Manual reduction of the joint masses during patient positioning allows for effective stabilization in a single surgical session.

Management of combined atlas and axis fractures: a systematic review

Background

Combined atlas-axis fractures are rare occurrences with substantially higher rates of neurologic deficits compared with isolated injuries. Given the intricate anatomic relationship between the atlas and axis vertebra, variable fracture patterns may occur, warranting special considerations from surgeons.

Methods

A systematic search of PubMed and EMBASE was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Relevant studies on acute combined atlas-axis fractures that provided data on patient demographics, presentation (injury mechanism, neurologic deficits, fracture type), management, complications, and study conclusions were reviewed.

Results

A total of 22 articles published from 1977 to 2022, comprising 230 patients, were included in the final analysis. Thirty-seven of the 213 patients (17%) presented with neurologic deficits. The most common atlas injuries were posterior arch fractures (54/169 patients; 32%), combined posterior arch/anterior arch fractures (44/169 patients; 26%), and anterior arch fractures (43/169 patients; 25%). The most common axis injuries were type II odontoid fractures (115/175 patients; 66%). Of the 127 patients managed operatively (127/230 patients; 55%), 45 patients (35%) were treated with C1-C2 posterior spinal fusion, 33 patients (26%) were treated with odontoid screw fixation and anterior/posterior C1-C2 trans-articular screws, 16 patients (13%) were treated with occiputocervical fusion and 12 patients (9%) were treated with odontoid screw fixation alone.

Conclusions

Management strategies are generally based on the type of axis fracture as well as the condition of the transverse ligament. Patients with stable fractures can be successfully managed nonoperatively with a cervical collar or halo immobilization. Combined atlas-axis fractures with an atlantodental interval >5 mm, C1 lateral mass displacement >7 mm, C2-C3 angulation >11° or an MRI demonstrating a disrupted transverse ligament are suggestive of instability and are often successfully managed with surgical intervention. There is no consensus regarding surgical technique.

Assessment of atlantoaxial rotation: how accurate is clinical measurement? a comparative study of cervical range of motion using MRI and standard orthopedic techniques

PURPOSE

Measurement of neck rotation is currently reliant on radiologic imaging. Given the radiation exposure for CT imaging and the additional inconvenience for the patients, an alternative assessment is needed. Goniometers are comfortably to use and easy to access, also for private consulting. The aim of this study was the assessment of whether a handheld goniometer can be used for accurately measuring the rotation of C1-C2.

METHODS

Clinical measurement of rotation was taken in flexed position of the neck. As comparison functional MRI was used. The measured rotation of C1-C2 was compared to identify the accuracy of the goniometer, in comparison to functional MRI scan.

RESULTS

Analysis of accuracy using a goniometer and dynamic MRI to assess C1-2 axial rotation showed significant differences for absolute values, but not regarding the percentage of rotation compared to total neck rotation.

CONCLUSION

The goniometer is exact to impartially determine the percentage contribution of C1-2 rotation to total neck rotation.

Biomechanical Assessment of Fracture Loads and Patterns of the Odontoid Process

STUDY DESIGN

Laboratory study.

OBJECTIVE

This study aimed to investigate the biomechanical competence and fracture characteristics of the odontoid process.

SUMMARY OF BACKGROUND DATA

Odontoid fractures of the second cervical vertebra (C2) represent the most common spine fracture type in the elderly. However, very little is known about the underlying biomechanical fracture mechanisms.

MATERIALS AND METHODS

A total of 42 C2 human anatomic specimens were scanned via computed tomography, divided in six groups, and subjected to combined quasistatic loading at -15°, 0°, and 15° in sagittal plane and -50° and 0° in transverse plane until fracturing. Bone mineral density (BMD), height, fusion state of the ossification centers, stiffness, yield load, and ultimate load were assessed.

RESULTS

While lowest values for stiffness, yield load, and ultimate load were observed at load inclination of 15° in sagittal plane, no statistically significant differences were observed between the study groups ( P ≥0.235). BMD correlated positively with yield load ( r2 =0.350, P <0.001) and ultimate load ( r2 =0.955, P <0.001) but not with stiffness ( r2 =0.082, P =0.07). The specimens with clearly distinguishable fusion of the ossification centers revealed less data scattering of the biomechanical outcomes.

CONCLUSION

Load direction plays a subordinate role in traumatic fractures of the odontoid process. BMD was associated with significant correlation to the biomechanical outcomes. Thus, odontoid fractures appear to result from of an interaction between the load magnitude and bone quality.

Surgical Management of Type II Displaced Dens Fractures Improves One-year Mortality in Elderly Patients

STUDY DESIGN

Retrospective cross-sectional analysis of US national data collected by PearlDiver Inc. database.

OBJECTIVE

To determine the rates of surgical/nonsurgical treatments and associated one-year mortality for displaced type II dens fractures without neurological deficit.

SUMMARY OF BACKGROUND DATA

Existing literature on dens fractures includes small series of patients with highly variable surgical rates. These studies contain insufficient data to determine the benefits of surgical or nonsurgical treatment as surgeon bias in treatment and selection of patients have significant effects on the results.

MATERIALS AND METHODS

Displaced type II dens fractures and upper cervical surgeries were identified using their respective International Classification of Diseases, 10th Revision (ICD-10) diagnosis and Current Procedural Terminology (CPT) codes. Inclusion criteria included patients older than 65, diagnosed with a displaced type II dens fracture, absent neurological damage, during the years 2015 to 2018. Age, sex, ICD-10 diagnosis codes, CPT codes, displacement type, and Elixhauser Comorbidity Index scores were obtained through the PearlDiver database. Patient-related variables and one-year mortality associated with surgical versus nonsurgical treatment were compared using univariate χ 2 analysis, odds ratios, and multivariate logistic regression analysis.

RESULTS

Among the 5300 patients who met our inclusion criteria, 59% (n=3108) were female, the mean age was 76.6 (±3.9) years old, and the average Elixhauser Comorbidity Index was 7.1 (±4.0). Only 8.3% (n=437) had surgical treatment for the displaced dens fracture. Multivariate logistic regression analysis for one-year mortality showed surgery was associated with decreased one-year mortality in all patients ( z =-6.26; P <0.001), patients between the ages of 65 and 74 ( z =-2.53; P =0.012), and patients over the age of 75 ( z =-5.81; P <0.001).

CONCLUSION

Despite surgery improving survival in elderly patients with type II dens fractures, surgical management is rarely pursued. Factors that independently increase the likelihood of surgery include younger age, male sex, and posterior displacement.

LEVEL OF EVIDENCE

4.

Case report: Challenging post-traumatic pseudoarthrosis of C2 odontoid fracture and extreme C1-C2 subluxation

Background:

Type II C2 odontoid fractures are common traumatic cervical spine lesions and have the highest risk of non-union without fusion. Pseudoarthrosis may lead to extreme anatomic deformation, and poor clinical outcomes. A 50-year-old male, following a traumatic C2 dens fracture treated when the patient was 44 years of age, newly presented at age 50 with pseudoarthrosis and severe C1-C2 subluxation that required a secondary fusion using a three-dimensional (3D) printed model for appropriate surgical planning.

Case Description:

A 44-year-old male underwent a C1 posterior arch osteotomy to treat cervical myelopathy after a type 2 odontoid fracture. Now at age 50, he newly presented with recurrent myelopathy, and marked cord compression due to a C2 odontoid-dens pseudoarthrosis, and extreme C1 subluxation over C2. A 3D model of the patients’ cervical-spine anatomy was created for surgical planning and led to an anterior C1-C2 freeing of the pseudoarthrosis, followed by a posterior C0-C1 decompression, deformity reduction, C0, C2 laminar, and C3/4 trans-articular arthrodesis. Six months postoperatively, the patient improved from a pre-operative mJOA score of 5 to a postoperative mJOA score of 14.

Conclusion:

A 3D model was successfully utilized to plan a secondary 360° fusion for a pseudoarthrosis diagnosed 6 years after an original C-C2type II odontoid fusion in a now 50-year-old male.

Cervical spine trauma: impact of different imaging classification systems in the clinical decision-making

Background and aim:

Considering the high rate of mortality and permanent disability related to vertebral traumas, an early and detailed diagnosis of the trauma and subsequently an immediate and effective intervention are crucial. Cervical vertebral injury classifications guide treatment choice through a severity grade based on radiological information. The purpose of the present study was to define which imaging classification system could provide the best morphological and clinical-surgical correlations for cervical spine traumas.

Methods:

We retrospectively analyzed patients evaluated for cervical spine trauma at our Institution in the period 2015-2020. Information regarding the morphological examination (using CT and MRI), the neurological evaluation, and the therapeutic management were collected. C3-C7 fractures were classified according to the SLIC and AOSpine criteria; axial lesions were classified according to the modified AOSpine for the C1-C2 compartment and through the Roy-Camille and the Anderson D’Alonzo system for the odontoid process of the axis.

Results:

29 patients were included in the final study population. Nine patients with axial spine trauma and 21 with subaxial cervical spine trauma. A conservative approach was applied in 16 patients while nine patients underwent neurosurgery. Considering the therapeutical indications provided by the SLIC system, a 76.9% accordance was found for patients with a <4 score, while a 100% concordance was calculated for patients with a >4 score undergoing neurosurgery. Regarding the AOSspine classification, a 28.6% concordance was observed for patients classified group B being treated with a posterior neurosurgical approach, while for patients belonging to subgroup C, considered for anterior neurosurgical approach, a 66.7% accordance was calculated.

Conclusions:

The study demonstrated a better morphological correlation for the AOSpine classification in subaxial trauma and the AOSpine and Anderson D’Alonzo in axial trauma. The therapeutic indication found a better correlation in the SLIC classification for subaxial trauma and the Anderson D’Alonzo for axial ones. (www.actabiomedica.it)

Clinical features and early post-operative complications of isolated C2 odontoid fractures: a retrospective analysis using a national inpatient database in Japan

PURPOSE

To examine the clinical features and post-treatment complications in patients with isolated C2 odontoid fractures.

METHODS

We extracted data for all patients who were admitted with C2 odontoid fractures from the Japanese Diagnosis Procedure Combination database between July 2010 and March 2017. We then compared the post-treatment complications during hospitalization according to treatment types: conservative treatment (with or without use of halo-vest) and surgery (anterior or posterior spinal fixation).

RESULTS

A total of 3167 patients (1533 men, 1634 women; mean age, 70 years) with isolated C2 odontoid fractures were identified, including 1124 patients (35%) aged ≥ 80 years. Among the total patients, 2476 (78%) received conservative treatment (with halo-vest, 728; without halo-vest, 1748). The remaining 691 patients (22%) underwent surgery (anterior surgery, 129; posterior surgery, 556; combined surgery, 6). There were no differences between the conservative treatment and surgery groups in baseline characteristics and preexisting comorbid conditions except for age (71 vs. 69 years, p = 0.042). In-hospital death occurred in 136 patients (4.3%). There was no significant difference in in-hospital mortality between the two groups (overall, conservative treatment 4.6% vs. surgery 3.0%, p = 0.066; age ≥ 80 years, conservative treatment 7.2% vs. surgery 5.4%, p = 0.34). Use of halo-vest was not associated with increased mortality (with halo-vest 3.7% vs. without halo-vest 5.0%, p = 0.15).

CONCLUSION

The great majority of isolated odontoid fractures occurred in elderly patients. Conservative treatment and surgery had similarly low in-hospital mortality. Use of halo-vest was not associated with an increase in mortality.

The use of Grauer classification in the management of type II odontoid fracture in elderly: Prognostic factors and outcome analysis in a single centre patient series

OBJECTIVE

To evaluate the results of Type II odontoid fractures management in the elderly, according to the Grauer classification.

METHODS

Consecutive patients with type II odontoid fracture, age > 65 years and follow-up longer than 3 months were included. Fracture management was proposed according to Grauer classification. Peri-surgical risk factors, NDI, VAS and rate of fusion were evaluated according to the treatment modality and compared between conservative and surgical groups.

RESULTS

Thirty-four patients were considered eligible for the study; 2 patients showed a Type IIa fracture, 30 patients a type IIb, and 2 patients a type IIc. Type IIa patients underwent conservative treatment that resulted in failure. A conservative management was adopted in 9 cases with type IIb due to patient preference or anaesthesiologic reasons with a treatment success at 6 months of 11%. Trans-odontoid stabilization was adopted in 21 type IIb cases with an evidence of bony or fibrous union at 6 months of 95% and a median NDI of 20%. A posterior approach was reserved for 2 type IIc fracture patients and in 6 cases as rescue surgery (bony union at 6 months of 100%; median NDI 37%). Higher Lakshmanan grade, gap and displacement of the fracture were found as significant risk factor for fracture non-union (p < 0.05).

CONCLUSIONS

The surgical group presented better clinical and radiological outcome and the anterior approach proved to achieve the best results in type IIb fractures. The presence of osteoporosis and fracture spatial features should be duly considered in the decision-making process.

A Technique for the In Vivo Study of Three-dimensional Cervical Segmental Motion Characteristics After Anterior Screw Fixation for Odontoid Process Fractures

STUDY DESIGN

Kinematics of the cervical spine was investigated using cone beam computed tomography (CBCT) images combined with three dimensions to three dimensions (3D-3D) registration technology in patients after anterior odontoid screw fixation (AOSF) surgery.

OBJECTIVE

The aim of this study was to investigate in vivo 3D cervical motion characteristics of patients who had undergone AOSF surgeries.

SUMMARY OF BACKGROUND DATA

AOSF surgery is a classic surgical method for the treatment of odontoid fracture, but there are few studies that investigated its effect on in vivo biomechanics of the cervical spine. Postoperative biomechanical characters of the atlantoaxial joint (C1-C2) and the caudal adjacent segment (C2-C3) have yet to be clarified.

METHODS

The study involved 14 patients subjected to a procedure of AOSF with lag screw. Subjects were matched with 14 healthy controls. All subjects underwent CBCT scanning of the cervical spine under seven functional positions. A 3D-3D registration was performed for each vertebra at each functional position to calculate the segmental motion characteristics. The ranges of motion (ROMs) of the C1-C2, C2-C3, and the overall cervical spine (C1-C7) for each of the functional positions were determined.

RESULTS

The ROMs of the AOSF group were significantly (P < 0.05) smaller than the control group in flexion-extension positions for the C1-C2 (7.0°vs.11.0°), C2-C3 (3.7°vs.6.7°) and C1-C7 (43.3°vs.54.4°). The twisting ROM of the C1-C2 was 39.3° in the AOSF group and 65.7° in the control (P < 0.05), the bending ROM of the C2-C3 was 2.8° in the AOSF group and 8.9° in the control (P < 0.05). The twisting ROM of C1-C7 segment was 63.2° for the AOSF and 98.1° for the healthy control groups (P < 0.05).

CONCLUSION

Although AOSF surgery reduced the flexion-extension ROMs of all investigated spinal segments, additionally, it reduced twisting ROMs of C1-C2 and C1-C7, but only lateral bending ROM of C2-C3, when compared with the control group. The data implied that the AOSF surgery would result in different biomechanics changes in the atlantoaxial segment and caudal adjacent segment. Longer-term follow-up studies of larger patient cohorts are necessary to evaluate the clinical outcomes of patients after the AOSF surgery.Level of Evidence: 3.

Feasibility analysis of the use of anterior screw fixation in the treatment of pediatric odontoid fracture

BACKGROUND

This study aimed to determine the feasibility of using anterior percutaneous screw fixation to treat odontoid fractures in children of different ages based on computed tomography (CT) measurements.

METHODS

A total of 176 children were enrolled and divided into 3 groups: group A (<6 years of age; 18 males and 22 females), group B (6 to 12 years old; 40 males and 35 females), and group C (12 to 18 years old; 34 males and 27 females). Using 2-dimensional CT reconstruction technology, we measured the children's odontoid parameters, including the coronal external diameter of the base of the odontoid process, the sagittal external diameter of the base of the odontoid process, the length of the odontoid process, the height of the axis vertebral body, and the angle between the axial line of the odontoid process and the vertical line of the anterosuperior border of the C3 vertebral body.

RESULTS

The mean coronal external diameter of the odontoid process base in children under 6 years old was 4.21±1.62 mm, which was not sufficient to accommodate a single screw. Among children aged 6 to 12 years old, this parameter varied widely, and the mean diameter was 5.50±2.80 mm. In the 12- to 18-year-old group, the diameter was 8.64±1.68 mm, which is similar to that of adults. The values of the total height of the axis, and the angle between the axial line of the and the vertical line of the anterosuperior C3 vertebral body border were lower than those for adults.

CONCLUSIONS

The percutaneous odontoid screw fixation technique is not recommended for children under 6 years old. For children aged 6 to 18 years old, this technique is feasible, but individual differences must be considered preoperatively. Selecting the appropriate screw diameter, length, and angle according to the actual CT measurement result is critical.

C1-C2 Injury: Factors influencing mortality, outcome, and fracture healing

BACKGROUND

C1-C2 injury represents 25-40% of cervical injuries and predominantly occurs in the geriatric population.

METHODS

A prospective multicentre study was conducted under the aegis of the french spine surgery society (SFCR) investigating the impact of age, comorbidities, lesion type, and treatment option on mortality, complications, and fusion rates.

RESULTS

A total of 417 patients were recruited from 11 participating centres. The mean ± SD age was 66.6 ± 22 years, and there were 228 men (55%); 5.4% presented a neurological deficit at initial presentation. The most frequent traumatic lesion was C2 fracture (n = 308). Overall mortality was 8.4%; it was 2.3% among those aged ≤ 60 years, 5.0% 61-80 years, and 16.0% > 80 years (p < 0.001). Regarding complications, 17.8% of patients ≤ 70 years of age presented with ≥ 1 complication versus 32.3% > 70 years (p = 0.0009). The type of fracture did not condition the onset of complications and/or mortality (p > 0.05). The presence of a comorbidity was associated with a risk factor for both death (p = 0.0001) and general complication (p = 0.008). Age and comorbidities were found to be independently associated with death (p < 0.005). The frequency of pseudoarthrosis ranged from 0 to 12.5% up to 70 years of age and then constantly and progressively increased to reach 58.6% after 90 years of age.

CONCLUSIONS

C1-C2 injury represents a serious concern, possibly life-threatening, especially in the elderly. We found a major impact of age and comorbidities on mortality, complications, and pseudarthrosis; injury pattern or treatment option seem to have a minimal effect.

Unusual Clinical Course of Odontoid Fracture: Transient Prehospital Cardiopulmonary Arrest

Odontoid fracture is the most common type of cervical spine fracture in the elderly. Neurological injury due to odontoid fracture is uncommon, but if the injury is severe, it can lead to cardiac arrest. We present a case of odontoid fracture with transient cardiac arrest just after the fall, which fully recovered in a few minutes before arrival at the hospital.

A 62-year-old man fell down on a street, and compressions were performed by a witness. On arrival of the emergency medical service, he showed pulseless electrical activity. After two minutes of cardiac resuscitation, he experienced a return of spontaneous circulation and was breathing spontaneously. On arrival at our hospital, his blood pressure was 171/106 mmHg, heart rate was 100 beats per minute, and respiratory rate was 12 times per minute, but he was at Glasgow Coma Scale 3 with an alcohol odor from exhaled breath. Six hours after admission, his level of consciousness improved, and he complained of neck pain and difficulty in movement of his arms and legs. CT revealed a fracture and posteriorly displaced C2 bone. MRI showed a hyper-intense area from C1 to C2. We made a diagnosis of spinal cord injury caused by an odontoid fracture that led to cardiac arrest.

An odontoid fracture can cause transient cardiac arrest just after a fall. The possibility of odontoid fracture associated cervical spine injury should be considered in elderly and unconscious patients with minor trauma. Early CT cervical spine in selected patients can be helpful, especially in patients with cardiac arrest, even if it lasted for only a short prehospital period.

Outcomes of Patients Undergoing Anterior Screw Fixation for Odontoid Fracture and Analysis of the Predictive Factors for Surgical Failure

Objective

Anterior odontoid screw fixation (AOSF) is a safe and effective treatment for type II and rostral type III odontoid fracture. This study aimed to report the outcomes of the AOSF surgery and evaluate the potential risk factors of surgical failure.

Methods

We enrolled 63 patients who underwent AOSF. Follow-up computed tomography was performed 6 months after the surgery and once a year thereafter to evaluate the union. Clinical data including the age, sex, presenting symptoms, cause of injury, fracture gaps, dislocation position, degree of displacement, screw direction angle, and time interval from injury to operation were collected.

Results

Successful fusion was achieved in 55 patients (87.3%) and surgical failure occurred in 8 patients (12.7%). Variables such as age, sex, dislocation position, degree of displacement, screw direction angle, and time interval from injury to operation were not significantly associated with the surgical failure. However, surgical failure was statistically significantly associated with the fracture gap. The overall mean fracture gap at the time of injury was 1.29 mm (range, 0–3.11 mm), and the incidence of surgical failure was 8.3 times higher when the fracture gap at the time of injury was > 2 mm (p=0.019).

Conclusion

When performing AOSF in patients with type II or rostral shallow type III odontoid fractures, the displacement of the odontoid fracture fragment should be appropriately reduced to the aligning position before screw insertion and downward reduction should be achieved by perforation of the apical cortex of the odontoid during screw fixation, even if the surgery is delayed.

The Anterior Transarticular Fixation of C1/C2 in the Elderly With Dens Fractures

Background

Anterior transarticular screw fixation (ATSF) of C1/C2 can be used for the treatment of unstable dens fractures. Here, we evaluated the feasibility of an anterior C1/C2 fixation in elderly patients with unstable dens fractures. Furthermore, we tried to analyze safe entry zones for ATSF surgery.

Methods

A consecutive cohort of 13 patients with unstable dens fractures were treated with ATSF of C1/C2 between January 2015 and October 2016. If necessary, an additional screw was placed into the odontoid process. The placement was radiographically analyzed using the 3D Arcadis Orbic (Siemens, Erlangen, Germany). Additionally, computed tomography scans of the cervical spine from 50 trauma patients were analyzed to evaluate safe entry zones for anterior odontoid screw fixation and for ATSF.

Results

ATSF was performed in 13 cases (7 female, 6 male; mean age 81.80 years). One screw had to be corrected intraoperatively due to initial malplacement. Neurological deficits or an injury of the vertebral artery were not observed. All patients suffered from swallowing difficulties during the postoperative course, without lesions of the esophagus or the trachea. In 4 patients (30.8%), an additional posterior fixation was offered to the patients due to progressive loosening of the screws.The anatomical-radiographic analyzes revealed a significantly shallower angle of trajectory for anterior odontoid screw fixation (24.9° ± 5.85°) than for ATSF (39.1° ± 6.44° (left); 40.5° ± 6.79° (right) P = 0.02).

Conclusions

The ATSF of C1/C2 might be a valuable option in the treatment of instable C1/C2 fractures, especially in the elderly or in patients with short necks and/or high body mass index due to the steeper trajectory compared with odontoid screw placement. Yet available screws seem to be of inferior resistance compared with the biomechanical properties of a dorsal fixation. Further studies should focus on screws with better mechanical properties and probably additional cement augmentation.

Level of Evidence

4.

Association Between Frailty Status and Odontoid Fractures After Traumatic Falls: Investigation of Varying Injury Mechanisms Among 70 Elderly Odontoid Fracture Patients

OBJECTIVES

To determine significant associations between patient frailty status and odontoid fractures across common traumatic mechanisms of injuries (MOIs) in the elderly.

DESIGN

Retrospective review.

SETTING

Single, academic-affiliated hospital with full surgical services.

PATIENTS/PARTICIPANTS

Patients 65 years or older with traumatic odontoid fractures were included.

INTERVENTION

Nonoperative management (soft/hard collar, halo, traction tongs, and Minerva) and/or operative fixation.

MAIN OUTCOME MEASUREMENTS

Modified frailty index (mFI), MOI, concurrent injuries, inpatient length of stay (LOS), reoperation, and mortality rates.

RESULTS

Seventy patients were included (80.6 ± 8.5 years, 60% F, 88% European, 10% Maori/Pacific, 1.4% Asian, Charlson Comorbidity Index 5.3 ± 2.2, mFI 0.21 ± 0.15). The most common MOIs were falls (74.3%), high-speed motor vehicle accidents (MVAs) (17.1%), low-speed MVAs (5.7%), and pedestrian versus car (2.9%). Patients with traumatic falls exhibited significantly higher mFI scores (0.25) compared with low-speed MVAs (0.16), high-speed MVAs (0.08), and pedestrian versus car (0.01) (P = 0.003). Twenty-seven patients with odontoid fractures were frail, 33 were prefrail, and 10 were robust. Ninety-two percent of frail patients had a traumatic fall as their MOI, as opposed to 73% of prefrail and 30% of robust patients (P < 0.001). Prefrail and frail patients were 4.3 times more likely than robust patients to present with odontoid fractures through traumatic fall [odds ratio (OR): 4.33 (1.47-12.75), P = 0.008], and frailty increased likelihood of reoperation [OR: 4.2 (1.2-14.75), P = 0.025] and extended LOS [OR: 5.71 (1.05-10.37), P = 0.017]. Frail patients had the highest 30-day (P = 0.017) and 1-year mortality (P < 0.001) compared with other groups.

CONCLUSION

Patients with traumatic odontoid fractures from falls were significantly more frail in comparison with any other MOIs, with worse short- and long-term outcomes.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Fusion rates for odontoid fractures after treatment by anterior odontoid screw versus posterior C1-C2 arthrodesis: a meta-analysis

OBJECTIVE

For odontoid fractures, surgical treatment approaches including anterior odontoid screw fixation approach and the posterior C1-C2 arthrodesis approach are generally adopted in practice. However, the choice of different surgical procedures remains controversial. In addition to surgical technique, the fusion rate is an important factor contributing to the clinical efficacy. Therefore, this study was aimed to investigate the discrepancy in fusion rate between these two surgical approaches through synthesizing the currently available evidence on the topic.

METHODS

A computerized search of Ovid, Medline, Embase, and the Cochrane library up to December 2017 for literature on the complication rate during odontoid fracture treatment was conducted. Risk ratio (RR) with its 95% confidence interval (CI) was pooled to assess fusion rates after surgical treatments, including anterior odontoid screw fixation approach or posterior C1-2 arthrodesis procedure, for patients with odontoid fractures.

RESULTS

Thirteen studies were enrolled in the meta-analysis. Results show that no significant difference was found in the overall fusion rate (RR = 0.96, 95% CI 0.90-1.01). There was no significant heterogeneity among the studies (p value = 0.60). As to age- and economic-level subgroups, there was no statistical evidence to suggest an association of the patient age and economy development level with the choice of surgical approach. However, it is shown that better fusion rates of patients (≥ 60 years) in developed countries received a better fusion rates after posterior fixation compared with anterior group using the fixed-effect model (RR = 0.88, 95% CI 0.79-0.98).

CONCLUSION

Elderly patients (≥ 60 years) underwent posterior C1-2 arthrodesis fixation shows higher fusion rates in developed countries comparing with patients who underwent anterior odontoid screw fixation. Overall, there is no significant discrepancy between these two surgical approaches. However, the conclusion should be verified by further study enrolling larger sample size.

Treatment of Odontoid Type II Fractures in Octogenarians: Balancing Two Different Treatment Strategies

OBJECTIVE

Demographic changes have led to a higher incidence of C-2 fractures, especially in elderly patients. For patients with type II fractures, treatment remains controversial, as discussed by Anderson and D'Alonzo, due to the rising morbidity and mortality rates for any treatment. The aim of this study was to compare conservative and surgical management in patients with type II C-2 fractures regarding outcomes, complications, and the mortality rate.

METHODS

A retrospective analysis was performed of the medical records, X-rays, and/or computed tomography scans of patients ≥80 years of age with type II fractures who were admitted to our Department of Neurosurgery between January 1990 and December 2017. The success of treatment was evaluated 3 months after surgery.

RESULTS

In total, 125 patients were included, of whom 98 were treated surgically and 27 were treated conservatively. Surgical treatment was successful in 90.8% of cases, while conservative treatment was successful in 70.0%. The in-hospital mortality was 14.29% and the 3-month mortality was 27.8% in the surgical group, compared to 3.7% and 20% in the conservatively treated group. The in-hospital complication rate was 22.4% in the surgically treated patients and 7.4% in the conservatively treated patients.

CONCLUSION

Surgical treatment of type II fractures seemed to be associated with higher success and complication rates than conservative treatment. Nevertheless, 3-month mortality was comparable in both groups. Therefore, we conclude that surgical treatment for type II fractures in elderly patients is superior to conservative management, although conservative treatment remains a valuable option in elderly patients with severe comorbidities.

A Modified Posterior C1/C2 Fusion Technique for the Management of Traumatic Odontoid Type II Fractures by Using Intraoperative Spinal Navigation: Midterm Results

OBJECTIVES

To assess midterm safety and efficacy of a modified Goel-Harms technique for the treatment of odontoid instabilities.

DESIGN

Longitudinal prospective cohort study.

SETTING

Urban Level 1 Trauma Center in Southwest Germany.

PATIENTS/PARTICIPANTS

Orthopaedic and neurosurgical trauma patients older than 18 years admitted for ≤24 hours.

MAIN OUTCOME MEASUREMENTS

The outcome was evaluated with respect to neurological outcome, radiological outcome and surgical complications. For the functional assessment, the EQ-5D questionnaire was used. Furthermore, the Neck Disability Index and visual analog scale for neck pain were determined. A median follow-up of 39 months (range: 6-97 months) was given.

RESULTS

Of the total sample (n = 56), 26 patients with an acute traumatic odontoid fracture type II underwent posterior atlantoaxial instrumentation using spinal navigation. Neck pain evaluated with visual analog scale and Neck Disability Index showed a significant decrease at final follow-up compared to preoperative values (P < 0.05). According to the EQ-5D, the valuation of quality of life after C1/C2 fusion showed an excellent outcome with complete recovery in most cases (0.7-1).

CONCLUSIONS

Our results demonstrate satisfactory and maintained midterm clinical and radiological results after a median follow-up of 39 months. With the use of intraoperative spinal navigation, we demonstrate a modified C1/C2 posterior fusion technique, rendering accuracy, feasibility, and overall safety.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Treatment of Odontoid Fractures: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU)

STUDY DESIGN

Narrative review.

OBJECTIVE

To establish recommendations for the treatment of odontoid fractures based on current literature and the knowledge of the experts of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU).

METHODS

Narrative review of the literature. Analyzing treatment algorithms of German trauma and spine centers as members of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU).

RESULTS

There are many influencing factors leading to appropriate treatment of odontoid fractures such as age, bone quality, arthrosis, classification, and type of the fracture. Conservative nonoperative treatment is appropriate for stable undislocated displaced odontoid fractures. Anterior osteosynthesis with 1 or 2 screws leads to good results in the classical unstable type II odontoid fracture in patients with good bone quality. However, modifiers have been identified by the working group leading to higher complication and failure rates. For these cases, more stable constructs and/or posterior approaches are indicated.

CONCLUSIONS

Operation seems to be standard treatment for odontoid fractures. However, in the aged population, conservative treatment should be considered as morbidity and mortality rise significantly in the group of >75 years. Conservative treatment may also be started within stable nondislocated fractures, but then regular controls have to be performed. If operation is indicated, many influencing factors have to be considered for appropriate approach and technique. The classification of Anderson and D'Alonzo is still standard. To create an adequate treatment algorithm, dislocation displacement and instability have to be identified. Stable odontoid fractures are treated conservatively non-operatively, but if so regular controls have to be performed. Unstable and/or dislocated displaced odontoid fractures are treated by anterior osteosynthesis with 1 or 2 screws. The technique is demanding and leads to elevated complication and failure rates if modifiers are apparent. In these cases, posterior instrumentation or fusion of C1 and C2 is favorable. In the aged population (>80 years), operative therapy is critical as postoperative morbidity complication and mortality rates rise significantly. As there is still some bias in the treatment algorithms, the working group recommends establishment of a prospective study to result in more objective statements.

Surgical Treatment for Odontoid Fractures in Patients with Long-Standing Ankylosing Spondylitis: A Report of 3 Cases and Review of the Literature

BACKGROUND

Ankylosing spondylitis (AS) is classified as a chronic inflammatory seronegative rheumatic arthritis. Patients with AS are more likely to sustain a fracture of the cervical spine compared with the general population. Most fractures occur in the lower cervical spine and manifest at the level of the intervertebral disc. There have been few reports about the surgical treatment for upper cervical spine fractures in patients with AS, especially odontoid fractures. We present 3 cases of odontoid fracture in patients with long-standing AS.

METHODS

Odontoid fracture with atlantoaxial displacement was identified on radiologic imaging in 3 patients. In 1 patient, fracture was a missed diagnosis after initial trauma, and the fracture and displacement were discovered 3 months later owing to aggravation of symptoms. Posterior occipitocervical fusion with iliac autograft was performed under general anesthesia in all cases.

RESULTS

All 3 patients recovered postoperatively without any complications related to surgery. Cervical radiographs obtained at 12-month follow-up demonstrated healed fracture and replacement of the atlantoaxial joint.

CONCLUSIONS

Odontoid fracture with atlantoaxial dislocation in patients with long-standing AS is uncommon. Clinicians must be cautious in assessing such patients with any episode of trauma. Computed tomography and magnetic resonance imaging can be helpful in demonstrating occult odontoid fractures. Posterior occipitocervical fusion with internal fixation may benefit these patients, although at the cost of sacrificing the last motion segment.

Feasibility of Modified Anterior Odontoid Screw Fixation: Analysis of a New Trajectory Using 3-Dimensional Simulation Software

BACKGROUND

Anterior odontoid screw fixation (AOSF) has been suggested as the optimal treatment for type II and some shallow type III odontoid fractures. However, only the classical surgical trajectory is available; no newer entry points or trajectories have been reported.

METHODS

We evaluated the anatomic feasibility of a new trajectory for AOSF using 3-dimensional (3D) screw insertion simulation software (Mimics). Computed tomography (CT) scans of patients (65 males and 59 females) with normal cervical structures were obtained consecutively, and the axes were reconstructed in 3 dimensions by Mimics software. Then simulated operations were performed using 2 new entry points below the superior articular process using bilateral screws of different diameters (group 1: 4 mm and 4 mm; group 2: 4 mm and 3.5 mm; group 3: 3.5 mm and 3.5 mm). The success rates and the required screw lengths were recorded and analyzed.

RESULTS

The success rates were 79.03% for group 1, 95.16% for group 2, and 98.39% for group 3. The success rates for groups 2 and 3 did not differ significantly, and both were significantly better than the rate for group 1. The success rate was much higher in males than in females in group 1, but the success rate was similar in males and females in the other 2 groups. Screw lengths did not differ significantly among the 3 groups, but an effect of sex was apparent.

CONCLUSIONS

Our modified trajectory is anatomically feasible for fixation of anterior odontoid fractures, but further anatomic experiments and clinical research are needed.

Nonoperative management of C-2 dens fractures: Single center experience and review of the literature

OBJECTIVE

The demographic change in the population leads to a rising number of patients presenting with fractures of the cervical spine, especially C-2, due to falls. With an increase of co-morbidities in these elder patients, the risk for intra- and postoperative complications is increased likewise. Thus, an alternative strategy instead of operative management of these fractures should be taken into account whenever possible. Conservative management of dens fractures in the elderly is still a subject of great controversy despite numerous studies on this topic. The aim of this study was to analyze the rate of successful osseous consolidation of C-2 fractures with conservative treatment by wearing a semi-rigid collar or halo thoracic vest without further surgical intervention.

PATIENTS AND METHODS

We analyzed the medical records and CT-scan of the cervical spine of 254 patients with C-2 fractures retrospectively, who were admitted to our department between January 1990 and September 2015. Fractures were diagnosed by CT-scan of the cervical spine and classified according to the Anderson - D`Alonzo classification. 183 patients were submitted to surgery as treatment of choice. In 71 patients a conservative management with external immobilization was chosen. The latter group was subjected to study analysis.

RESULTS

71 patients (mean age 74.08 years ± 16.06 years) were diagnosed with C-2 fractures (Typ I: 4; Typ II 36; Typ III: 31) and treated conservatively using a Philadelphia collar (n = 57), or a halo-thoracic vest (n = 14), respectively. 12 patients were lost to follow up and excluded from further analysis. Conservative treatment of the fractures was deemed successful when a bony consolidation of the fracture in follow-up CT scans was seen (45 of 59 patients; 76.3%). 20 patients with a Type II fracture (20/28, 71.4%) showed a successful ossification. In 14 patients (overall 23.7%; Typ I: 1 (7.14%), Typ II: 8 (57.14%), Typ III: 5 (35.71%)) external immobilization failed to achieve primary stability. These patients were submitted to consecutive surgery.

CONCLUSION

From our data it can be concluded that elderly patients, presenting with non-dislocated Type II fractures of the axis without accompaining neurological deficits, will have a more than 70% chance for a bony consolidation by conservative management. Consolidation rates may be estimated even higher in Type I and III fractures. Therefore, we suggest that external immobilization might be a valuable option to treat elderly patients with these fractures under certain circumstances.

Short-Term Complications of Anterior Fixation of Odontoid Fractures

STUDY DESIGN

Retrospective study.

OBJECTIVE

Anterior fixation of odontoid fracture has been associated with high morbidity and mortality in small, single institution series. Identifying risk factors may improve risk stratification and highlight factors that could be optimized preoperatively. The objective of this study was to determine the 30-day complication rate following anterior fixation of odontoid fractures and to identify associated risk factors among patients in a large national database.

METHODS

Patients who underwent anterior fixation were identified in the American College of Surgeons National Quality Improvement Program database (ACS NSQIP) from 2007 to 2012. Patient demographics, medical comorbidities, perioperative complications, and postoperative complications up to 30 days were analyzed by univariate and multivariate analysis.

RESULTS

Overall, 103 patients met criteria for the study. The average age was 73.9 years and patients were predominantly white (85.4%). Cardiac comorbidity was common (66.0%), as were dependent functional status (14.6%) and bleeding disorders (13.6%). Complications occurred in 37.9% of patients, and mortality was high (6.8%). Age, white race, and history of bleeding disorders were independently predictive of complications in the multivariate analysis. The postoperative hospital stay was >5 days for 45.6% of patients.

CONCLUSION

In a large, multicenter database study, anterior fixation of odontoid fracture was associated with high morbidity and mortality. Although advanced age was associated with increased risk of complications, patients undergoing anterior fixation were older, on average, than in prior studies. Bleeding disorder was a potentially modifiable risk factor for complications that could be optimized prior to surgery.

Clinical and radiological union rate evaluation of type 2 odontoid fractures: A comparison between anterior screw fixation and halo vest in elderly patients

Purpose:

Odontoid fracture is a very common cervical injury, especially in elderly patients. Despite the high frequency, the appropriate management is still debated. The aim of this study is to evaluate clinical and radiological outcomes after anterior screw fixation or halo vest (HV) in type II odontoid fracture in elderly patients.

Materials and Methods:

Between January 2013 and December 2015, 135 consecutive patients affected by odontoid process were found. According to inclusion and exclusion criteria, 57 patients were included in the study. Patients were evaluated with visual analog scale (VAS), Smiley–Webster Scale (SWS), Italian Version of the Neck Disability Index (NDI), and patient satisfaction during follow-up. Furthermore, radiological data were evaluated for bone healing. Student's t-test or Fisher's exact test was used between groups, analyzing radiological and clinical results, and level of statistical significance was set at P < 0.05.

Results:

Seventeen patients were female and 40 were male. Twenty-seven patients were included in surgical group (SG) while 30 were included in HV group with a mean follow-up of 37.74 ± 10.52 months. A significant difference (P < 0.05) between groups was found for pseudoarthrosis, with a lower rate for SG. No significant differences in term of VAS, NDI, and SWS were found between groups (P > 0.05); SG reached higher satisfaction than HV group (P = 0.0271).

Conclusions:

Both treatments are equivalent in terms of clinical outcomes, and they are a valuable choice in the management of type II odontoid fracture. However, it must be considered that patients could slightly tolerate HV and may need a change of treatment.

Anterior fixation of odontoid fractures: results

Objective

To evaluate the clinical and radiological outcomes of the surgical treatment in patients diagnosed with odontoid fracture who underwent open reduction and internal fixation (ORIF) with screws.

Methods

This was a retrospective study with nine patients. Pain (visual analog scale [VAS]) and neurological status (Frankel scale) were assessed. The neck disability index (NDI) and the post-operative cervical range of motion were calculated. The cervical spine was radiologically evaluated (X-ray and CT) pre- and postoperatively.

Results

The mean age of patients was 70 years. All patients presented type IIb (Grauer classification) fractures, with a mean deviation of 2.95 mm. Two patients had subaxial lesions. The mean follow-up was 30 months. The mean time from trauma to surgery was seven days. The pre-operative Frankel score was E in all except one patient (B), in whom a post-operative improvement from B to D was observed. Post-operative pain was 2/10 (VAS). A total of 77% of patients presented a mild or moderate disability (NDI). Six patients regained full range of cervical movement, and bone union required approximately 14 weeks. Pseudarthrosis complications were observed in two patients (77% union rate), one patient presented screw repositioning and one case, dysphonia.

Conclusion

Delayed diagnosis is still an issue in the treatment of odontoid fractures, especially in elderly patients. Concomitant lesions, especially in younger patients, are not uncommon. The literature presents high fusion rates with ORIF (≥80%), which was also observed in the present study. However, surgical success depends on proper patient selection and strict knowledge of the technique. This pathology presents a reserved functional prognosis in the medium-term, especially in the elderly.

Treatment of type II odontoid fracture with a novel technique: Titanium cable-dragged reduction and cantilever-beam internal fixation

Surgical methods for type II odontoid fracture can be classified into 2 main groups: anterior or posterior approach. A more effective way to achieve bone fusion with the lowest possible surgical risk is needed. Therefore, the aim of our study was to describe and evaluate a novel technique, cable-dragged reduction/cantilever beam internal fixation for the treatment of type II odontoid fracture.This was a retrospective study enrolled 34 patients underwent posterior cable-dragged reduction/cantilever-beam internal fixation surgery. Medical records, rates of reduction, the location of the instrumentation and fracture healing during follow-up were analyzed. Once fracture healing was obtained, instrumentation was removed. Neck pain (scored using a visual analog scale [VAS]), neck stiffness, patient satisfaction, and neck disability index (NDI) were recorded before and after removing the instrumentation during follow-up.The mean duration of follow up was 22.8 ± 5.3 months. There was no iatrogenic damage to nerves or blood vessels. Radiographic evaluation showed complete reduction in the 20 patients with fracture displacement and satisfactory fracture healing in all 34 cases. Titanium cable breakage was observed in 4 patients after fracture healing. After removal of instrumentation, significant improvements were seen in neck-pain VAS score, neck stiffness, patient satisfaction, and NDI (all P < .01).Posterior cable-dragged reduction/cantilever-beam internal fixation was an optimal salvage maneuver to conventional surgical methods such as anterior screw fixation and C1-C2 screw-rod system. The operative difficulty and incidence of nerve and vascular injury were reduced. Its major disadvantage is the exposure and screw-setting at C3, which is left intact in traditional surgery, and it is suitable only for patients with intact C1 posterior arches.

Anterior Versus Posterior Approaches for Odontoid Fracture Stabilization in Patients Older Than 65 Years: 30-day Morbidity and Mortality in a National Database

STUDY DESIGN

Retrospective cohort analysis.

OBJECTIVE

To compare 30-day perioperative clinical outcomes of surgical odontoid stabilization by an anterior or posterior operative approach in elderly patients.

SUMMARY OF BACKGROUND DATA

Surgical stabilization of odontoid fractures is superior to nonoperative management in geriatric patients. How elderly patients with odontoid fractures fare after anterior and posterior approaches, however, is not well defined.

MATERIALS AND METHODS

Retrospective review of the prospectively collected American College of Surgeons National Surgical Quality Improvement Program database (2005-2013). Elderly patients (≥65 y) with odontoid fractures who underwent odontoid stabilization through anterior or posterior approaches were identified by International Classification of Diseases 9th Revision/Common Procedure Terminology codes. Exclusion criteria included concomitant subaxial spine surgery, instrumentation noncontiguous with the atlantoaxial interval, and combined approaches. Baseline demographics and perioperative details were compared. Adverse events, mortality, reoperation, discharge, and readmission rates within 30 days of operation were compared using bivariate and multivariate generalized linear regressions.

RESULTS

One hundred forty-one patients (male-81; female-60; average age: 77.8±6.5 y; anterior approach-48; posterior approach-93) were analyzed. Patients scheduled to have a posterior approach had significantly more nonunions preoperatively and higher body mass indices. Operative times for posterior surgeries were significantly longer. Age, comorbidities, functional dependence, time to surgery, and length of hospital stay were similar between groups. There were no significant differences in the relative risk (RR) of the composite outcome of "any adverse event" after adjusting for differences in baseline characteristics. Patients who underwent an anterior approach were more likely to have an unplanned hospital readmission (RR=8.95; 95% confidence interval, 2.21-36.29; P=0.002) and have significantly more revision operations (RR=19.51; 95% confidence interval, 2.49-152.62; P=0.005) than patients who had a posterior operation.

CONCLUSIONS

An anterior approach for odontoid fracture stabilization in patients ≥65 years old were associated with shorter operative times and greater RRs of unplanned readmissions and revision operations within 30 days of surgery relative to a posterior approach.

Percutaneous anterior C1/2 transarticular screw fixation: salvage of failed percutaneous odontoid screw fixation for odontoid fracture

BACKGROUND

The objective of this study is to investigate the outcomes and safety of using percutaneous anterior C1/2 transarticular screw fixation as a salvage technique for odontoid fracture if percutaneous odontoid screw fixation fails.

METHODS

Fifteen in 108 odontoid fracture patients (planned to be treated by percutaneous anterior odontoid screw fixation) were failed to introduce satisfactory odontoid screw trajectory. To salvage this problem, we chose the percutaneous anterior C1/2 transarticular screw fixation technique in treatment of these patients. The visual analogue score (VAS) of neck pain and Neck Disability Index (NDI) of all patients were scored at pre-operation, 3 months after operation, and final follow-up. Additional, technique-related complications were recorded and collected.

RESULTS

Percutaneous C1/2 transarticular screw fixation was performed successfully in all 15 patients whose odontoid screw fixation failed. No technique-related complications (such as nerve injury, spinal cord injury, and esophageal injury) occurred. The VAS of neck pain and NDI score improved significantly (P = 0.000) after operation, and no significant differences were found when compared to 93 non-salvage patients who successfully performed the percutaneous anterior odontoid screw fixation. No screw loose or breakage occurred, all of the odontoid fractures achieve radiographic fusion, bony fusion bridge could be observed at the C1/2 lateral articular facet on 9/15 patients.

CONCLUSIONS

We suggest that percutaneous anterior C1/2 transarticular screw fixation is a good alternative salvage technique if percutaneous odontoid screw fixation failed, and it is a minimally invasive, feasible, and safe technique.

Clinical Results of Odontoid Fractures according to a Modified, Treatment-Oriented Classification

OBJECTIVE

Odontoid fracture is common in cervical injury, representing about 20% of total cervical fractures. Classic odontoid fracture classification focused on anatomy of fracture site has no treatment recommendation and a modified treatment-oriented classification of odontoid fracture was suggested in 2005. We reviewed our odontoid fracture patients to assess the feasibility and efficacy of Grauer's classification.

METHODS

Between October 2000 and September 2015, we collected data from patients who came to our institute for odontoid fracture. Demographic data of patients was reviewed, and neck visual analog scale (VAS) score and fusion rate were assessed by reviewing electronic medical records retrospectively.

RESULTS

Sixty-nine patients out of a total of eighty two odontoid fracture patients were reviewed according to Grauer's classification. Neck VAS of all subtypes in odontoid fracture classification were decreased at last follow-up (p=0.001). Overall fusion rate was 88.4% at last follow-up. Concordance rate between Grauer's recommendation and our treatment was 69.9%, especially in type II with the concordance higher than 80%. Complication was minimal representing 7.2%, only in types I and III.

CONCLUSION

In this study, there were statistically significant improvement in all subtypes in terms of neck VAS at the last follow up, especially in types II and III. Grauer's classification appears to be meaningful to decide treatment plan for odontoid fractures, especially type II odontoid fracture.

Is It Feasible to Treat Odontoid Fractures via Primary Posterior Reduction and Fixation without Fusion?

OBJECTIVE

To evaluate results and feasibility of primary posterior reduction and fixation without fusion using C1-C2 screw-rod system for odontoid fractures.

METHODS

This study comprised a consecutive series of 46 patients with odontoid fractures. Posterior reduction and fixation without fusion using the C1-C2 screw-rod system was performed, and instrumentation was not removed. Radiologic outcomes were assessed on follow-up computed tomography or plain radiographs. Visual analog scale of neck pain, American Spinal Injury Association impairment scale, patient satisfaction, neck disability index, and range of motion of flexion extension and rotation of the cervical spine were recorded and analyzed.

RESULTS

Mean follow-up time was 4.1 years (range, 12 months to 8 years). Radiographic evaluation indicated solid fusion of odontoid fractures in all cases and no implant failures. No patient reported severe neck pain at follow-up. Neurologicl evaluation showed there was 1- to 2-grade improvement in patients with neurologic deficit. Of patients, 31 reported acceptable outcomes, and 15 reported good outcomes. Range of motion of rotation of the cervical spine and neck disability index score gradually improved significantly during 1 year of follow-up with no obvious change after that. Rate of neck disability index score improvement was 85%.

CONCLUSIONS

Posterior reduction and fixation without fusion can be successfully performed for healing of odontoid fractures with acceptable results and minimal morbidity.

An in vitro biomechanical evaluation of an expansive double-threaded bi-directional compression screw for fixation of type II odontoid process fractures: A SQUIRE-compliant article

Odontoid process fracture accounts for 5% to 15% of all cervical spine injuries, and the rate is higher among elderly people. The anterior cannulated screw fixation has been widely used in odontoid process fracture, but the fixation strength may still be limited under some circumstances. This study aims to investigate the biomechanical fixation strength of expansive double-threaded bi-directional compression screw (EDBCS) compared with cannulated lag screw (CLS) and improved Herbert screw (IHS) for fixation of type II odontoid process fracture.Thirty fresh cadaveric C2 vertebrae specimens were harvested and randomly divided into groups A, B, and C. A type II fracture model was simulated by osteotomy. Then the specimens of the 3 groups were stabilized with a single CLS, IHS, or EDBCS, respectively. Each specimen was tested in torsion from 0° to 1.25° for 75 s in each of 5 cycles clockwise and 5 cycles anticlockwise. Shear and tensile forces were applied at the anterior-to-posterior and proximal-to-distal directions, respectively, both to a maximum load of 45 N and at a speed of 1 mm/min.The mean torsional stiffness was 0.309 N m/deg for IHS and 0.389 N m/deg for EDBCS, which were significantly greater compared with CLS, respectively (0.169 N m/deg) (P < .05 and P < .05). The mean shear stiffness for the EDBCS was 238 N/mm, which was significantly greater than CLS (150 N/mm) and IHS (132 N/mm) (P < .05 and P < .05). All 3 screws only partly restored tensile stiffness, but not significantly.Fixation with the EDBCS can improve the biomechanical strength for odontoid process fracture compared with CLS and IHS, especially in terms of torsional and shear stiffness.

Odontoid Fracture in a Patient With Diffuse Idiopathic Skeletal Hyperostosis

Nonoperative management of fractures in the setting of diffuse idiopathic skeletal hyperostosis (DISH) or ankylosing spondylitis is often unsuccessful. The subaxial spine is a common site of hyperextension fractures in the setting of DISH. Fractures of the upper cervical spine are uncommon in DISH. We report, to our knowledge, the first case describing successful nonoperative management of a type 2 odontoid fracture in a patient with DISH. We discuss the patient’s initial presentation, physical examination, imaging findings, and management. A 73-year-old male presented with neck pain to the emergency department after sustaining a ground-level fall. Computed tomography of the cervical spine demonstrated a minimally displaced type 2 odontoid fracture in the setting of extensive DISH. He was immobilized with a hard cervical collar as the definitive management of his fracture. The collar was discontinued after 3 months. At his 2-year follow-up, he had a stable fibrous nonunion at the fracture site with tolerable neck pain. Flexion–extension radiographs demonstrated a stable alignment, and nonoperative management was continued. In selected patients with odontoid fractures in the setting of DISH, there is a role for nonoperative management alongside close monitoring.

A comparison of anterior screw fixation and halo immobilisation of type II odontoid fractures in elderly patients at increased risk from anaesthesia

Aims

We performed a retrospective, comparative study of elderly patients with an increased risk from anaesthesia who had undergone either anterior screw fixation (ASF) or halo vest immobilisation (HVI) for a type II odontoid fracture.

Patients and Methods

A total of 80 patients aged 65 years or more who had undergone either ASF or HVI for a type II odontoid fracture between 1988 and 2013 were reviewed. There were 47 women and 33 men with a mean age of 73 (65 to 96; standard deviation 7). All had an American Society of Anesthesiologists score of 2 or more.

Results

Patients who underwent ASF had a significantly better outcome than those who were treated by HVI. There was a rate of nonunion of 10% after ASF and 23% after HVI. Failure of reduction or fixation occurred in 11 patients (15%) but there was no significant difference between the two groups. Mortality rates were also similar: 9% (n = 3) after ASF and 8% (n = 4) after HVI.

Conclusion

We conclude that ASF is the preferred method of treatment in this group of elderly patients, having a significantly higher rate of fusion, better clinical outcome and a similar rate of general and treatment-related complications. Cite this article: Bone Joint J 2016;98-B:1222–6.

The Feasibility of Two Screws Anterior Fixation for Type II Odontoid Fracture Among Arabs

STUDY DESIGN

Retrospective, cross-sectional study.

OBJECTIVE

To evaluate the feasibility of two screws anterior fixation of the odontoid process among Arab adults.

SUMMARY OF BACKGROUND DATA

Anterior screw fixation is the treatment of choice for type II odontoid fractures. In order to perform the procedure safely, the diameter of the odontoid process should be wide enough to allow for the placement of one or two screws.

METHODS

A retrospective review of 156 computed tomography scans of the cervical spine was done. The included patients were Arabs, adults (at least 18 years old), and had no evidence of upper cervical spine trauma, deformity, infection, tumor, or surgery. The minimum external transverse diameter (METD), minimum internal transverse diameter (MITD), minimum external anteroposterior diameter (MEAD), and minimum internal anteroposterior diameter (MIAD) of the odontoid process were measured. A P value of ≤0.05 was considered as the cutoff level of statistical significance.

RESULTS

Our study included 94 (60.3%) males and 62 (39.7%) females. The mean age of the subjects was 37.8 ± 16.9 years (range 18-85). The mean values of the METD, MITD, MEAD, and MIAD were 8.7 ± 1.0 mm, 6.0 ± 1.1 mm, 10.3 ± 1.0 mm, and 7.4 ± 1.1 mm, respectively. Men had larger diameters compared to women. This was statistically significant for METD (P = 0.035) and MEAD (P < 0.001). The METD was <9.0 mm in 95 (60.9%) subjects, while the MITD was <8.0 mm in 153 (98.1%) subjects. These findings were not significantly different between males and females.

CONCLUSION

Two screws anterior fixation of type II odontoid fracture is not feasible among the majority of Arabs.

LEVEL OF EVIDENCE

3.

Combined Type II Odontoid Fracture with Jefferson's Fracture Treated with Temporary Internal Fixation

An 18-year-old male presented after a motor vehicle rollover accident. Computed tomography (CT) scan confirmed the diagnosis of Type II odontoid fracture. Considering the patient's young age and the limitations of C1-C2 fusion including significant loss of cervical rotation, temporary internal fixation with a lateral mass fixation of C1 and pedicle fixation of C2 without fusion was done. CT scan done at 6-month follow-up visit showed healed odontoid fracture and excellent C1-C2 alignment. At ninth postoperative month, internal fixation was removed. Patient had normal movements of cervical spine at 1-year follow-up. Temporary internal fixation can be an important tool in the armamentarium of the surgeon in treating type II odontoid fractures in young adults and children. This strategy avoids the complications halo fixation and immobilizes the unstable C1-C2 segment without fusion. Removal of the internal fixation after healing allows restoration of the rotational motion.

[Imitation of an Anderson type II dens fracture by a motion artefact in computed tomography : Four case examples]

Computed tomography (CT) is the method of choice in the diagnosis and classification of odontoid fractures with a sensitivity of more than 99 % and a specificity almost equally as high. In this article we report on four cases where CT-generated motion artefacts exactly mimicked an Anderson type II fracture of the dens axis, initially leading to a wrong diagnosis. Although this seems to be a very rare event, these cases indicate that overlooked CT motion artefacts can lead to severe consequences and attention must be paid to the radiological signs outlined in this report.

Conservative versus surgical treatment for type II odontoid fractures in the elderly: Grading the evidence through a meta-analysis

BACKGROUND

Odontoid fractures are common C-spine fractures in the elderly. However, the optimal treatment of odontoid fractures in the elderly is, still subject to controversy.

HYPOTHESIS

Surgical treatment has several advantages on conservative treatment, such as reduced mortality and lower incidence of non-union. This meta-analysis was performed to identify the efficacy of conservative treatment compared with surgical treatment and provides recommendations for using these procedures to treat type II odontoid fractures in the elderly.

MATERIALS AND METHODS

A systematic search of all studies published was conducted using the PubMed, EMBASE, OVID, ScienceDirect and Cochrane CENTRAL databases. The randomized controlled trials (RCTs) and non-randomized controlled trials (non-RCTs) that compared conservative treatment with surgical treatment and provided data on clinical effects were identified. The included trials were screened out strictly based on the criterion of inclusion and exclusion. The quality of included trials was evaluated. RevMan 5.1 was used for data analysis.

RESULTS

Twelve studies involving 730 patients met the inclusion criteria. There were 441 patients with conservative treatment and 289 with surgical treatment. The results of meta-analysis indicated that no difference with regard to the mortality was noted (P > 0.05) between the two procedures. However, there was statistically significant difference with respect to the non-union numbers (P < 0.05) between the two procedures.

DISCUSSION

Conservative treatment and surgical treatment are both effective procedures for treating type II odontoid fractures in the elderly. Compared with surgical treatment, there is no significant difference in mortality; With respect to non-union numbers, conservative treatment numbers are higher than surgical treatment. Due to the poor quality of the evidence currently available, high quality RCTs are required. Level of evidence Level II: low-powered prospective randomized trial meta-analysis.

Odontoid process fractures: the role of the ligaments in maintaining stability. A biomechanical, cadaveric study

Aims: We wished to investigate the role of the cervical ligaments in maintaining atlantoaxial stability after fracture of the odontoid process.

Methods: We dissected eight fresh-frozen cadaveric cervical spines to prepare the C1 and C2 vertebrae for biomechanical analysis. The C1 and C2 blocks were mounted and biomechanical analysis was performed to test the stability of the C1-C2 complex after cutting the odontoid process to create an Anderson and D’Alonzo type II fracture then successive division of the atlantoaxial ligaments. Biomechanical analysis of stiffness, expressed as Young’s modulus, was performed under right rotation, left rotation and anterior displacement.

Results: The mean Young’s modulus in anterior displacement decreased by 37% when the odontoid process was fractured (p = 0.038, 95% confidence interval 0.04–1.07). The mean Young’s modulus in anterior displacement decreased proportionally (compared to the previous dissection) by the following percentages when the structures were divided: facet joint capsules (bilateral) 16%, ligamentum flavum 27%, anterior longitudinal ligament 10%. These differences did not reach statistical significance (p > 0.05).

Discussion: We have found that the odontoid process itself may account for up to 37% of the stiffness of the C1-C2 complex and that soft tissue structures account for further resistance to movement. We suggest magnetic resonance imaging (MRI) of the soft tissues in the acute setting of a minimally displaced odontoid process fracture to plan management of the injury. If the MRI determines that there is associated ligament injury it is likely that the fracture is unstable and we would suggest operative management.

Posterior atlantoaxial fixation: A cadaveric and fluoroscopic step-by-step technical guide

Background:

Atlantoaxial surgical fixation is widely employed treatment strategy for a myriad of pathologies affecting the stability of the atlantoaxial joint. The most common technique used in adults, and in certain cases in children, involves a posterior construct with C1 lateral mass screws, and C2 pars or pedicle screws. This technical note aims to provide a step-by-step guide to this procedure using cadaveric and fluoroscopic images.

Methods:

An embalmed, human, cadaveric, specimen was used for this study. The subject did not have obvious occipital-cervical pathology. Dissections and techniques were performed to mimic actual surgical technique. Photographs were taken during each step, and the critical aspects of each step were highlighted. Fluoroscopic images from a real patient undergoing C1/C2 fixation were also utilized to further highlight the anatomic-radiographic relationships. This study was performed without external or industry funding.

Results:

Photographic and radiographic pictures and drawings are presented to illustrate the pertinent anatomy and technical aspects of this technique. The nuances of each step, including complication avoidance strategies are also highlighted.

Conclusions:

Given the widespread utilization of this technique, described step-by-step guide is timely for surgeons and trainees alike.

Noninvasive management of an odontoid process fracture in a toddler: case report

Study Design Case report. Objective Odontoid process fractures represent an uncommon injury in small children, with their optimal management remaining unclear. We present a case of conservatively managed displaced type 2 odontoid process fracture in a small child. Methods We analyzed clinical and radiographic outcomes of a restrained 2-year-old girl involved in a motor vehicle accident who sustained a displaced type 2 odontoid process fracture and was treated conservatively in a semirigid Aspen collar. Results The fracture progressively healed with callus formation evident at 6 weeks. By 12 weeks, the patient was asymptomatic and had regained head control and a full range of movement. Radiographic remodeling of the fracture was seen to improve over the 6-month follow-up. Conclusion This case illustrates that displaced type 2 odontoid process fractures can be successfully managed conservatively in small children.

Pooled analysis of non-union, re-operation, infection, and approach related complications after anterior odontoid screw fixation

Background

Anterior odontoid screw fixation (AOSF) has been one of the most popular treatments for odontoid fractures. However, the true efficacy of AOSF remains unclear. In this study, we aimed to provide the pooled rates of non-union, reoperation, infection, and approach related complications after AOSF for odontoid fractures.

Methods

We searched studies that discussed complications after AOSF for type II or type III odontoid fractures. A proportion meta-analysis was done and potential sources of heterogeneity were explored by meta-regression analysis.

Results

Of 972 references initially identified, 63 were eligible for inclusion. 54 studies provided data regarding non-union. The pooled non-union rate was 10% (95% CI: 7%–3%). 48 citations provided re-operation information with a pooled proportion of 5% (95% CI: 3%–7%). Infection was described in 20 studies with an overall rate of 0.2% (95% CI: 0%–1.2%). The main approach related complication is postoperative dysphagia with a pooled rate of 10% (95% CI: 4%–17%). Proportions for the other approach related complications such as postoperative hoarseness (1.2%, 95% CI: 0%–3.7%), esophageal/retropharyngeal injury (0%, 95% CI: 0%–1.1%), wound hematomas (0.2%, 95% CI: 0%–1.8%), and spinal cord injury (0%, 95% CI: 0%–0.2%) were very low. Significant heterogeneities were detected when we combined the rates of non-union, re-operation, and dysphagia. Multivariate meta-regression analysis showed that old age was significantly predictive of non-union. Subgroup comparisons showed significant higher non-union rates in age ≥70 than that in age ≤40 and in age 40 to <50. Meta-regression analysis did not reveal any examined variables influencing the re-operation rate. Meta-regression analysis showed age had a significant effect on the dysphagia rate.

Conclusions/Significances

This study summarized the rates of non-union, reoperation, infection, and approach related complications after AOSF for odontoid factures. Elderly patients were more likely to experience non-union and dysphagia.

A fatal iatrogenic right vertebral injury after transoral odontoidectomy and posterior cervical stabilization for a type II odontoid fracture

The authors present a singular case of an iatrogenic right vertebral artery injury, involving a 67 year-old man, who reported a type II odontoid fracture (Anderson and D'Alonzo Classification) and posterior atlantoaxial dislocation following a road traffic accident. A small injury involving the right vertebral artery occurred as a consequence of transoral odontoidectomy and posterior cervical stabilization. It was caused by bone spicules of spinal origin and their presence was confirmed by the histological section of the right vertebral artery at the level of C1-C2. The case confirms how iatrogenic vertebral artery injuries during cervical spine surgery may be potentially lethal, especially where complications arise some days after surgery.