Nonoperative versus operative management of type II odontoid fracture in older adults: a systematic review and meta-analysis

J Neurosurg Spine 40:45–53, 2024

Odontoid fractures are the most common fracture of the cervical spine in adults older than 65 years of age. Fracture management remains controversial, given the inherently increased surgical risks in older patients. The objective of this study was to compare fusion rates and outcomes between operative and nonoperative treatments of type II odontoid fractures in the older population.

METHODS A systematic literature review was performed to identify studies reporting the management of type II odontoid fractures in patients older than 65 years from database inception to September 2022. A meta-analysis was performed to compare rates of fusion, stable and unstable nonunion, mortality, and complication.

RESULTS Forty-six articles were included in the final review. There were 2822 patients included in the different studies (48.9% female, 51.1% male), with a mean ± SD age of 81.5 ± 3.6 years. Patients in the operative group were significantly younger than patients in the nonoperative group (81.5 ± 3.5 vs 83.4 ± 2.5 years, p < 0.001). The overall (operative and nonoperative patients) fusion rate was 52.9% (720/1361). The fusion rate was higher in patients who underwent surgery (74.3%) than in those who underwent nonoperative management (40.3%) (OR 4.27, 95% CI 3.36–5.44). The likelihood of stable or unstable nonunion was lower in patients who underwent surgery (OR 0.37, 95% CI 0.28–0.49 vs OR 0.32, 95% CI 0.22–0.47). Overall, 4.8% (46/964) of nonoperatively managed patients subsequently required surgery due to treatment failure. Patient mortality across all studies was 16.6% (452/2721), lower in the operative cohort (13.2%) than the nonoperative cohort (19.0%) (OR 0.64, 95% CI 0.52–0.80). Complications were more likely in patients who underwent surgery (26.0% vs 18.5%) (OR 1.55, 95% CI 1.23–1.95). Length of stay was also higher with surgery (13.6 ± 3.8 vs 8.1 ± 1.9 days, p < 0.001).

CONCLUSIONS Patients older than 65 years of age with type II odontoid fractures had higher fusion rates when treated with surgery and higher stable nonunion rates when managed nonoperatively. Complications and length of stay were higher in the surgical cohort. Mortality rates were lower in patients managed with surgery, but this phenomenon could be related to surgical selection bias. Fewer than 5% of patients who underwent nonoperative treatment required revision surgery due to treatment failure, suggesting that stable nonunion is an acceptable treatment goal.

Surgery Decreases Nonunion, Myelopathy, and Mortality for Patients With Traumatic Odontoid Fractures

Neurosurgery 93:546–554, 2023

Existing literature suggests that surgical intervention for odontoid fractures is beneficial but often does not control for known confounding factors.

OBJECTIVE: To examine the effect of surgical fixation on myelopathy, fracture nonunion, and mortality after traumatic odontoid fractures.

METHODS: We analyzed all traumatic odontoid fractures managed at our institution between 2010 and 2020. Ordinal multivariable logistic regression was used to identify factors associated with myelopathy severity at follow-up. Propensity score analysis was used to test the treatment effect of surgery on nonunion and mortality.

RESULTS: Three hundred and three patients with traumatic odontoid fracture were identified, of whom 21.6% underwent surgical stabilization. After propensity score matching, populations were well balanced across all analyses (Rubin’s B < 25.0, 0.5 < Rubin’s R < 2.0). Controlling for age and fracture angulation, type, comminution, and displacement, the overall rate of nonunion was lower in the surgical group (39.7% vs 57.3%, average treatment effect [ATE] = À0.153 [À0.279, À0.028], P = .017). Controlling for age, sex, Nurick score, Charlson Comorbidity Index, Injury Severity Score, and selection for intensive care unit admission, the mortality rate was lower for the surgical group at 30 days (1.7% vs 13.8%, ATE = À0.101 [À0.172, À0.030], P = .005) and at 1 year was 7.0% vs 23.7%, ATE = À0.099 [À0.181, À0.017], P = .018. Cox proportional hazards analysis also demonstrated a mortality benefit for surgery (hazard ratio = 0.587 [0.426, 0.799], P = .0009). Patients who underwent surgery were less likely to have worse myelopathy scores at follow-up (odds ratio = 0.48 [0.25, 0.93], P = .029).

CONCLUSION: Surgical stabilization is associated with better myelopathy scores at follow-up and causes lower rates of fracture nonunion, 30-day mortality, and 1-year mortality.

Outcomes following anterior odontoid screw versus posterior arthrodesis for odontoid fractures

J Neurosurg Spine 39:196–205, 2023

Odontoid fractures can be managed surgically when indicated. The most common approaches are anterior dens screw (ADS) fixation and posterior C1–C2 arthrodesis (PA). Each approach has theoretical advantages, but the optimal surgical approach remains controversial. The goal in this study was to systematically review the literature and synthesize outcomes including fusion rates, technical failures, reoperation, and 30-day mortality associated with ADS versus PA for odontoid fractures.

METHODS A systematic literature review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines by searching the PubMed, EMBASE, and Cochrane databases. A random-effects meta-analysis was performed and the I 2 statistic was used to assess heterogeneity.

RESULTS In total, 22 studies comprising 963 patients (ADS 527, PA 436) were included. The average age of the patients ranged from 28 to 81.2 years across the included studies. The majority of the odontoid fractures were type II based on the Anderson-D’Alonzo classification. The ADS group was associated with statistically significantly lower odds to achieve bony fusion at last follow-up compared to the PA group (ADS 84.1%; PA 92.3%; OR 0.46; 95% CI 0.23–0.91; I 2 42.6%). The ADS group was associated with statistically significantly higher odds of reoperation compared to the PA group (ADS 12.4%; PA 5.2%; OR 2.56; 95% CI 1.50–4.35; I 2 0%). The rates of technical failure (ADS 2.3%; PA 1.1%; OR 1.11; 95% CI 0.52–2.37; I 2 0%) and all-cause mortality (ADS 6%; PA 4.8%; OR 1.35; 95% CI 0.67–2.74; I 2 0%) were similar between the two groups. In the subgroup analysis of patients > 60 years old, the ADS was associated with statistically significantly lower odds of fusion compared to the PA group (ADS 72.4%; PA 89.9%; OR 0.24; 95% CI 0.06–0.91; I 2 58.7%).

CONCLUSIONS ADS fixation is associated with statistically significantly lower odds of fusion at last follow-up and higher odds of reoperation compared to PA. No differences were identified in the rates of technical failure and all-cause mortality. Patients receiving ADS fixation at > 60 years old had significantly higher and lower odds of reoperation and fusion, respectively, compared to the PA group. PA is preferred to ADS fixation for odontoid fractures, with a stronger effect size for patients > 60 years old.

Percutaneous Direct Pars Repair in Young Athletes

Neurosurgery 92:263–270, 2023

Lumbar pars defects are common in adolescent athletes and are often due to recurrent axial loading and traumatic stressors.

OBJECTIVE: To present an updated case series of young athletes who underwent percutaneous direct pars repair after failure of conservative management.

METHODS: A single-center, nonrandomized, retrospective observation study of athletes who were referred for minimally invasive direct pars repair after failure of at least 6 months of conservative management was performed. Summary demographic information, clinical features of presentation, perioperative and intraoperative radiographic imaging, and visual analog scale back pain scores were collected and analyzed.

RESULTS: A total of 21 patients were included (mean age [± SD] 17.47 ± 3.02 years, range 14-25 years), 6 of whom were female (29%). All patients presented with bilateral pars fractures, with L5 being the most frequent level involved (n = 13). The average follow-up time was 31.52 ± 9.38 months (range 3-110 months). The visual analog scale score for back pain was significantly reduced from 7.62 ± 1.83 preoperatively to 0.28 ± 0.56 at the final postoperative examination (P < .01). Fusion was noted in 20 of the 21 patients on final follow-up (95%).

CONCLUSION: Percutaneous direct pars repair is a safe and effective means in treating young adolescents who have failed conservative management. The advantages included minimized muscle and soft tissue dissection, reduced blood loss, and early mobilization and recovery. In young athletes who desire return to high-level physical activity, this surgical technique is of particular benefit and should be considered in this patient population.

Fifty years later: the “rule of Spence” is finally ready for retirement

J Neurosurg Spine 37:149–156, 2022

Determination of the optimal approach to traumatic atlas fractures with or without transverse atlantal ligament (TAL) injury requires a nuanced understanding of the biomechanics of the atlantoaxial complex. The “rule of Spence” (ROS) was created in 1970 in a landmark effort to streamline management of burst-type atlas fractures. The ROS states that radiographic evidence of lateral mass displacement (LMD) (i.e., the distance that the C1 lateral masses extend beyond the C2 superior articular processes) greater than 6.9 mm may indicate both a torn TAL and need for surgical management. Since then, the ROS has become ubiquitous in the spine literature about atlas injuries. However, in the decades since the original paper by Spence et al., modern research efforts and imaging advancements have revealed that the ROS is inaccurate on both fronts: it neither accurately predicts a TAL injury nor does it inform surgical decision-making.

The purpose of this review was to delineate the history of the ROS, demonstrate its limitations, present findings in the existing literature on ROS and LMD thresholds, and discuss the current landscape of management techniques for TAL injuries, including parameters such as the atlantodental interval and type of injury according to the Dickman classification system and AO Spine upper cervical injury classification system. The ROS was revolutionary for initially investigating and later propelling the biomechanical and clinical understanding of atlas fractures and TAL injuries; however, it is time to retire its legacy as a rule.

Posterior fusion for fragility type 2 odontoid fractures

J Neurosurg Spine 35:644–650, 2021

The purpose of this study was to evaluate the outcomes of elderly patients with type 2 odontoid fractures treated with an instrumented posterior fusion.

METHODS Ninety-three consecutive patients older than 65 years of age in whom a type 2 odontoid fracture had been treated with a variety of C1–2 posterior screw fixation techniques were retrospectively reviewed.

RESULTS The average age was 78 years (range 65–95 years). Thirty-seven patients had an additional fracture, 30 of which involved C1. Three patients had cervical spinal cord dysfunction due to their injury. All patients had comorbidities. The average total hospitalization was 9.6 days (range 2–37 days). There were 3 deaths and 19 major complications, the most common of which was pneumonia. No patient suffered a vertebral artery injury. Imaging studies were obtained in 64 patients at least 12 months postsurgery (mean 19 months). Fusion was assessed by dynamic radiographs in all cases and with a CT scan in 80% of the cases. Four of the 64 patients did not achieve fusion (6.25% overall). All patients in whom fusion failed had undergone C1 lateral mass fixation and C2 pars (1/29, 3.4%) or laminar (3/9, 33.3%) fixation.

CONCLUSIONS Instrumented posterior cervical fusions may be performed in elderly patients with acceptable morbidity and mortality. The fusion rate is excellent except when bilateral C2 translaminar screws are used for axis fixation.

A Retrospective Analysis in 1347 Patients Undergoing Cement Augmentation for Osteoporotic Vertebral Compression Fracture: Is the Sandwich Vertebra at a Higher Risk of Further Fracture?

Neurosurgery 88(2) 2021: 342–348

Multiple percutaneous vertebral cement augmentation may create sandwich vertebrae. Whether the sandwich vertebra is at higher risk of further fracture remains unknown.

OBJECTIVE: To compare the incidence of further fractures of sandwich vertebrae and adjacent vertebrae and to identify potential risk factors for sandwich vertebral fractures.

METHODS: Patients who underwent cement augmentation for osteoporotic vertebral compression fractures (OVCFs) in a single medical center between January 2012 and December 2015 were included. A sandwich vertebra was defined as an intact vertebra located between 2 previously cemented vertebrae. Demographic data and imaging findings were recorded. All patients were followed up for at least 24 mo postoperatively. During follow-up period, if the patient reported new-onset back pain with corresponding imaging findings, a diagnosis of sandwich vertebral fracture was made.

RESULTS: Among the 1347 patients who underwent vertebroplasty/kyphoplasty for OVCFs, 127 patients with 128 fracture levels met the criteria for sandwich vertebrae (females/males 100/27,mean age 77.8±7.7 yr old). The fracture locationwas most common in the thoraco-lumbar junction (T10-L2), 68.5% (87/127). The incidence of sandwich vertebral fracturewas 21.3%,whereas the incidence of adjacent level fracture of those with no sandwich vertebra was 16.4% (196/1194), P= .1879.

CONCLUSION: The incidence of sandwich vertebral fracture is not higher than that at the adjacent levels. The factor associated with further sandwich vertebral fracture was male gender. Once sandwich vertebral fracture occurred, patients may seek more surgical intervention than those with only adjacent fractures.

Odontoid screw placement for Anderson type II odontoid fractures: how do duration from injury to surgery and clinical and radiological factors influence the union rate? A multicenter retrospective study

J Neurosurg Spine 34:27–31, 2021

Anderson type II odontoid fractures are severe conditions, mostly affecting elderly people (≥ 70 years old). Surgery can be performed as a primary treatment or in cases of failed conservative management. This study aimed to investigate how duration from injury to surgery, as well as clinical, radiological, and surgical risk factors, may influence the union rate after anterior odontoid screw placement for Anderson type II odontoid fractures.

METHODS The authors conducted a retrospective multicenter study. Demographic, clinical, surgical, and radiological data of patients who underwent anterior odontoid screw placement for Anderson type II fractures were retrieved from institutional databases. Study exclusion criteria were prolonged corticosteroid drug therapy (> 4 weeks), polytraumatic injuries, oncological diagnosis, and prior cervical spine trauma.

RESULTS Eighty-five patients were included in the present investigation. The union rate was 76.5%, and 73 patients (85.9%) did not report residual instability. Age ≥ 70 years (p < 0.001, OR 6), female gender (p = 0.016, OR 3.61), osteoporosis (p = 0.009, OR 4.02), diabetes (p = 0.056, OR 3.35), fracture diastasis > 1 mm (p < 0.001, OR 8.5), and duration from injury to surgery > 7 days (p = 0.002, OR 48) independently influenced union rate, whereas smoking status (p = 0.677, OR 1.24) and odontoid process angulation > 10° (p = 0.885, OR 0.92) did not.

CONCLUSIONS Although many factors have been reported as influencing the union rate after anterior odontoid screw placement for Anderson type II fractures, duration from injury to surgery > 7 days appears to be the most relevant, resulting in a 48 times higher risk for nonunion. Early surgery appears to be associated with better radiological outcomes, as reported by orthopedic surgeons in other districts. Prospective comparative clinical trials are needed to confirm these results.

Conservative Management of Type II Odontoid Fractures in Older People

Neurosurgery 2020 DOI:10.1093/neuros/nyaa256

Type II odontoid fractures are a common cervical fracture in older people. Lower osseous-union rates are reported in those treated conservatively compared to surgically; however, the clinical relevance of a nonunion is unknown.

OBJECTIVE: To compare pain, disability, and quality of life in older people following conservativemanagement of type II odontoid fractures demonstrating osseous-union and nonunion.

METHODS: Electronic records were searched from 2008 to 2018 for adults ≥65 yr with type II odontoid fracture, managed in a semi-rigid collar. Clinical and demographic data were retrieved from electronic patient notes. Surviving patients were invited to complete questionnaires to assess pain, disability, and quality of life. Ethical approval was granted.

RESULTS: A total of 125 patients were identified: 36 (29%) demonstrated osseous-union, 89 (71%) had nonunion, of which 33 (40%) had radiological instability. Mean age at fracture was 84 yr (osseous-union 83 yr; nonunion 84 yr). A total of 53 had deceased (41 nonunion). Median length of survival was 77 mo for osseous-union vs 50 mo for nonunion; P = .02. No patient developed myelopathy during the follow-up period. Questionnaire response rate was 39 (58%). There were no statistically significant differences between the groups in terms of pain, disability, or quality of life (P>.05). Both groups reported mild disability and pain but low quality of life.

CONCLUSION: Management with a semi-rigid collar in older people with type II odontoid fracture is associated with low levels of pain and disability without statistically significant differences between those demonstrating osseous-union or stable or unstable nonunions. Conservative management appears to be a safe treatment for older people with type II fractures.

Minimally invasive posterior percutaneous transarticular C1–C2 screws: how I do it

Acta Neurochirurgica (2020) 162:2047–2050

Transarticular C1–C2 screw fixation, first described by Magerl, is a widely accepted used technique for C1–C2 instability with a good biomechanical stability and fusion rate.

Method We present a 69-year-old woman, who was diagnosed with a C2 Odontoid fracture type III and primarily treated with conservative treatment and collar. During first 2 weeks of follow-up, the patient developed cervical pain associated with C1–C2 instability. A minimally invasive posterior C1–C2 transarticular screw instrumentation with a percutaneus approach was performed.

Results and conclusion Minimally invasive approach with tubular transmuscular approach for C1–C2 transarticular screws instrumentation is safe and effective for C1–C2 instability.