THE EFFICACY AND SAFETY OF CERVICAL SPINE IMMOBILIZATION IN ELDERLY PATIENTS WITH CERVICAL SPINE FRACTURES: A SYSTEMATIC REVIEW

  Koech et al. observed that osseous union occurred in 50% of patients treated in collars and in 37.5% of patients managed with a halo. However, clinically stable union, with either osseous union or fibrous non-bony union (FNBU), was achieved in 90% of those in a collar and 100% those in a halo⁷. Patel et al. also found no significant difference in the rate of clinically stable union between patients managed with a halo or a collar⁸.  Koech and Patel found that 4.8% and 10%, respectively, went on to require operative fixation due to unstable non-union. No patients with FNBU developed myelopathy.

 All of the studies that compared collar and operative management found that operatively managed patients demonstrated higher rates of osseous union^9-11.  Malik did not differentiate between collar and halo in the ‘non-surgical’ cohort but again found an increased rate of osseous union in patients managed operatively compared to conservatively (100% and 80% respectively)¹². Interestingly, despite the lower rate of osseous union, Molinari et al. found slightly lower neck disability index and analogue pain scores in collar group compared to operative group¹⁰. Furthermore, no adverse outcomes were associated with FNBU at follow-up^9,10[10].

  Studies with elderly patients (>60) and no further subdivision according to age: Scheyerer found that patients managed with a collar had a significantly reduced survival rate at a follow-up compared to those managed operatively⁹. In contrast, Molinari found that those managed operatively had higher mortality (20% v. 12.5%) and complication rates (24% v. 6%), although formal statistical analysis was not conducted. Collar group complications were limited to two patients who developed significant skin breakdown in the neck region from prolonged full-time cervical collar wear (6%)¹⁰.  When comparing collar to halo, Damadi et al. found that there was no significant difference between mortality rates (23% and 29% respectively). Mortality correlated most strongly with the Injury Severity Score (ISS)¹³. Conversely, Tashjian et al. found that both the morbidity and mortality rates of patients with type II and III odontoid fractures were significantly higher in those treated with halo vests compared to collars (66% vs. 36% morbidity; 42% vs. 20% mortality)¹⁴. The risk of both pneumonia and cardiac arrest was also significantly higher in those wearing a halo. Whilst Malik et al. noted that total study in-hospital mortality was 11.2% they did not assess whether the difference between collar, halo and operative management reached statistical significance¹².

 When comparing patients managed with either collar or operatively, Chen et al. found that there was no significant difference in complication rate and median long-term survival, but that operative patients had a significantly longer hospital length of stay. Common complications included deep venous thrombosis, pulmonary embolism (10.7%), pneumonia, new neurological deficits, and necessitation of reintubation (7.1% each)¹⁵.

  Fagin et al. split 108 patients into three cohorts; ‘early operative’ (3 days post-injury) and non-operative. The assisted feeding, morbidity and mortality rate between the three groups were not significantly different, however, there were significantly fewer DVTs in the conservatively managed group (p=0.02). The percentage of patients discharged to a skilled nursing facility was similar among all three groups. The operatively managed groups had significantly more ventilator days and longer HLOS¹⁶.

  Studies of patients aged 75 and over; Graffeo et al. found that overall mortality following type II odontoid fracture was 26% at 30 days, and 41% at 1 year. However, there was no significant difference in mortality rates between those managed in a collar versus those managed operatively¹⁷. On the other hand, Smith et al. found that for patients with type II odontoid fracture, HLOS and number of complications per person was significantly higher in the operative group. The rate of major complications was also higher in those managed operatively, but did not reach statistical significance. Within the conservatively managed group, those treated with a halo vest were significantly more likely to develop airway compromise (including respiratory distress, pneumonia or intubation) than those treated with a collar¹⁸.  

 Woods et al. did not differentiate between collar and halo in the non-operative group, but it is worth noting that at 3 months there was a significantly lower mortality rate in the conservatively managed group, but at 1 and 5 years there was no longer a significant difference. A higher Charlson Co-morbidity Index (CCI) was associated with higher mortality in both operatively and non-operatively managed patients. There was a high rate of complications in both groups (37.5% and 47%, respectively) including persistent dysphagia, wound, pin site infection, stiffness and skin irritation¹¹.

  Studies comparing differences in outcome between different age sub-groups within the elderly population; Schoenfeld et al. found that in patients with type II odontoid fractures, overall mortality was 10% in hospital, 21% at 3 months and 31% at one year. At 3 months mortality was significantly associated with age (6% mortality in 65-74 year olds v. 18% mortality at 75-84 years old and 34% in the over 85s) but by one year this was no longer significant. Across the entire population, non-operative management had a non-significantly higher rate of mortality than operative management. There was no difference in mortality rates between halo and collar. The CCI was found not to be significantly associated with mortality when adjusted for confounding factors. When the population was sub-divided according to age, Cox regression modelling showed that a protective effect of surgery was seen in patients aged 65 to 74 years, for whom the hazard ratio associated with surgery for mortality after odontoid fracture was 0.4 (95% CI: 0.1–1.5). Those aged 75 to 84 years had a hazard ratio of 0.8 (95% CI: 0.3–2.3), and patients 85 years or older had a hazard ratio of 1.9 (95% CI: 0.6–6.1)¹⁹.

 Majercik et al. split 456 patients with c-spine fractures into two cohorts; 289 ‘young’ (5.

Discussion

    Morbidity and mortality rates among elderly patients with c-spine injuries are higher than those within the general geriatric trauma population¹. In the papers included in this study, in-patient mortality rates ranged from 10-31% and 30 day mortality ranged from 5.3-26%^14,15,17,19. The incidence of mortality begins to fall by 1 year post-injury but is still reported to be as high as 41%¹⁷. These findings concur with those of van Middendorp et al, who systematically reviewed mortality rates in elderly patients with c-spine fractures and found them to range from 6.45-34.3% by long-term follow-up, with the majority of the deaths occurring by short-term follow-up²⁰.

  Irrespective of injury severity or treatment modality, patient age is correlated with the risk of both complications and mortality in all 3 studies that investigated its effects^5,14,19. The lowest mortality rates were seen in studies with ‘younger’ elderly populations, whereas the highest rates of 26% at 30 days and 41% at 1 year, were in a study of patients aged 80 and above^14,15,19.

 Comparing mortality rates across the individual studies was hindered by the wide variation in the time to follow-up. Whilst some of the literature provided specific time frames (i.e. 30 day mortality), others only reported a non-specific ‘maximal follow-up’. In one instance, this ranged from 1-77 months, making it difficult to draw meaningful comparisons between this paper and others⁹.

  Treatment safety: Whilst age is known to be a significant risk factor, it is not the sole predictor of c-spine fracture outcomes. The various treatment modalities available are known to have significant differences in safety and efficacy in the elderly population. However, drawing conclusions about the most suitable treatment for these patients has previously been difficult due to the heterogeneity of the evidence available. Of the studies that investigated morbidity and mortality rates in those treated with a collar compared with surgical intervention, 3 found surgery to be associated with better outcomes^9,14,19, 2 found management with a collar to be significantly better^5,18, and 3 found no statistical difference^15-17. Two studies did not assess the significance of their results^10,12. This appears to reinforce the consensus that there is too greater variance in the published literature to recommend either collar or operative management.

However, when papers categorise patients based on their age, higher rates of concordance are demonstrated. Both studies of patients over the age of 75 found that conservative management was associated with lower mortality^11,17. Similarly, Schoenfeld et al. found that whilst surgical management is safer in those under the age of 75, by 85 years of age it is more hazardous than conservative treatment¹⁹. These findings are supported by Barlow et al. who used analytic modelling to compare Quality Adjusted Life Years (QALY) and cost effectiveness of conservative versus operative management of type II odontoid fractures. They found that QALY were higher in operatively managed patients up until the age of 85. After this, QALY was higher in patients managed conservatively. Across all age groups operative management was more costly²¹.

  Several studies specifically compared the halo-vest to cervical collars and/or surgical treatment. Three out of 6 found the halo vest to be associated with significantly higher rates of complications and mortality than other management options^5,14,18; the other 3 found no significant difference^8,13,19.  No studies found the halo to be safer than either collar or operative management. Tashjian et al. found that the complication rate of those patients managed with a halo is as high as double that of those managed in either a collar or operatively (42% v. 20%)¹⁴. Majercik et al. demonstrated that as age increases the risks associated with halo management are even greater⁵. The most common complications in patients managed with halo-vests were respiratory compromise secondary to aspiration or pneumonia and acute cardiac events^5,13,14,18.

  Efficacy of collars: Rates of bony union in operatively managed patients ranged varied widely (23-94%), as did those of patients managed in a collar (0-50%)^7,9. Of those fractures that do not demonstrate osseous union, many go on to achieve stable FNBU^7,8,10,11.  Koech et al. found that whilst osseous union only occurred in 50% of patients treated in collars and in 37.5% of patients managed with a halo, fracture stability was achieved in 90% and 100% respectively⁷. Previously FNBU was seen as an unsuccessful outcome due to the risk of subsequent myelopathy, as described by Anderson and D’Alonzo²². However, there were no adverse effects (including myelopathy, a deterioration in the neck disability index or pain analogue scale) associated with FNBU in the 4 studies that described it^7,8,10,11.  Given these findings, stable FNBU may be an acceptable treatment outcome in elderly patients with c-spine fractures.

  Limitations: The main limitation when comparing the different management options for c-spine fractures in the existing literature is that the majority of studies simply define patient cohorts as non-operative or operative. The non-operative cohort often consists of patients managed with both collar and halo, and the operative group may include different surgical approaches. Given that the morbidity and mortality data for collar and halo are often markedly different, grouping them together reduces the validity of any comparison with other management modalities. The same is true for those studies that compare the halo device to a combined cohort of collar and operatively managed patients. Currently no large scale randomised controlled trials specifically comparing collar, halo and the different operative management options exists. This reduces the value of any conclusions that can be drawn from the current literature.

  Conclusion: Morbidity and mortality rates in elderly patients with c-spine injuries are high. When those over 65 years of age are considered as one cohort, there is conflicting evidence as to which treatment modality is best. However, when separated into age subgroups, the current literature becomes more homogenous. It suggests that those under the age of 75 should be offered operative management and those over the age of 85 should be managed conservatively. However, between the ages of 75-85 there is still a lack of consensus.  A randomised controlled trial providing further delineation of treatment modality, stratified by age, is needed to draw definitive conclusion.

 Throughout all age groups operative management is associated with the highest rate of osseous union. However, there is no evidence to suggest that FNBU is associated with poorer short-term outcomes it this age group. The majority of the literature currently available is retrospective, with small participant numbers and short follow-up times. For this reason, further prospective studies comparing cervical collars and operative management over longer follow-up periods are needed to provide conclusive evidence regarding the risk of adverse outcomes in patients with FNBU.