Abstract
Background
Ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) are 2 distinct spondyloarthropathies characterized by progressive spinal ankylosis. Despite their differing pathophysiologies, both conditions create long rigid spinal segments that are vulnerable to unstable fractures. Although the existing literature often examines postoperative outcomes of either AS or DISH-related fractures, direct comparisons between the 2 disorders remains limited. This study aims to compare 3-month, 1-year, and 2-year outcomes following spinal fusion for cervical and noncervical fractures in patients with AS and DISH.
Methods
This was a retrospective cohort study. The TriNetX Global Collaborative Network database was queried using ICD-10 and CPT codes to identify adult patients (≥18 years) diagnosed with either AS or DISH who underwent spinal fusion surgery following cervical or noncervical fractures spinal fractures within the past twenty years. Propensity score matching (1:1) was performed using demographic variables and relevant comorbidities. Postoperative complications were assessed at 3-month, 1-year, and 2-year intervals and included medical, surgical, and infection-related outcomes. All statistical analyses were performed within the TriNetX platform, and a p-value < .05 was considered statistically significant.
Results
Among AS patients, the cervical group exhibited a significantly lower rate of surgical site infections (SSI) at 3 months (RR 0.44, p = .016), reduced thromboembolic events (RR 0.53, p = .03) at 2 years compared with AS patients with a noncervical fractures fracture. For both AS and DISH patients, cervical fractures were significantly associated with increased risk of spinal cord injury at all time points. In DISH patients, postoperative limb paralysis was also significantly higher following cervical fracture and fixation at all time points. Comparing all AS versus DISH patients, AS was associated with significantly higher mortality at 3 months (RR 2.16, p < .001), 1 year (RR 1.77, p < .001), and 2 years (RR 1.73, p < .001). Instrumentation failure was more common in AS patients at 1 year (RR 2.27, p = .018) and 2 years (RR 1.93, p = .032). Interestingly, pseudoarthrosis was significantly less common in AS compared to DISH at 1 year (RR 0.58, p = .006) and 2 years (RR 0.59, p = .0065).
Conclusions
Cervical fractures in both AS and DISH patients showed a higher risk of SCI compared to noncervical fractures, likely secondary to the narrowing of the canal within this region. Overall, AS patients had higher rates of mortality, instrumentation failure, and wound complications compared to those with DISH, while DISH patients had higher rates of pseudoarthrosis.
Keywords: Ankylosing spondylitis, Diffuse idiopathic skeletal hyperostosis, Spinal fracture, Spinal fusion, Cervical spine, Noncervical fractures spine
Introduction
Ankylosing spinal disorders (ADs) are a group of conditions characterized by pathological spinal ossification and progressive loss of spinal mobility [[1], [2], [3], [4]]. In the spine of patients with ADs, abnormal bony fusion of vertebral segments forms a long lever arm that inadequately diffuses mechanical forces [5,6]. Due to the impaired compensatory mechanical properties, minor traumas can cause unstable vertebral fractures [5,7]. These unstable fractures are associated with significantly higher rates of complications such as spinal cord injuries and delayed neurologic degeneration, as delayed recognition, inadequate immobilization, or improper transfers can further compromise the spinal canal [[5], [8], [9], [10], [11]]. Historically, nonoperative management of spinal fractures in patients with ADs have been linked with increased morbidity and mortality, thus surgical management is preferred [[12], [13], [14]].
Ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) are the 2 major etiologies of ADs which have become increasingly prevalent [15]. Both conditions result in rigid, hyperostotic spines, but arise from different pathophysiologic processes. AS is an inflammatory spondyloarthropathy involving progressive ossification, with a characteristic preference for the sacroiliac joints, syndesmophyte formation, and fusion of the posterior elements [1,5]. In contrast, DISH is a noninflammatory process commonly affecting the thoracic spine, characterized by flowing ossification of the anterior longitudinal ligament and relative preservation of the intervertebral disc space [2,16].
Although the existing literature often examines postoperative outcomes of either AS or DISH-related fractures, direct comparisons between the 2 disorders remains limited, particularly when taking into account the spinal region [14]. The present study primarily aims to evaluate the postoperative outcomes in patients with AS or DISH following spinal fusion for vertebral fractures at the 3-month, 1-year, and 2-year mark. Secondarily, the study compares how fractures in the cervical or noncervical fractures region may impact perioperative outcomes. The null hypothesis was that there was no difference in outcomes between the 2 cohorts (Fig. 1, Fig. 2).
Fig. 1.
Fracture in patients with cervical ankylosing spondylitis (AS). Can see ossification of the anterior spine spanning multiple cervical levels. Importantly, AS can invade into the intervertebral space, indicated by loss of disc height at multiple levels. Diagnosis requires (1) bilateral sacroiliitis with or without uveitis, and a positive HLA-B27 blood marker.
Fig. 2.
Thoracic fracture in patient with diffuse idiopathic skeletal hyperostosis (DISH). Criteria for diagnosis criteria include flowing (1) ossification along the anterolateral aspect of at least 4 contiguous vertebrae, (2) preservation of disc height of involved vertebrae segments and relative absence of significant degenerative changes; (3) absence of facet-joint ankylosis and absence of SI joint involvement.
Methods
Data source
This was a retrospective cohort study performed using the TriNetX Global Collaborative Research Network database. TriNetX is a federated database that aggregates deidentified patient information from electronic health records from a large group of health care organizations within the United States. Data available includes demographics, diagnoses, medications, and procedures. As the study uses deidentified patient data, ethical approval was waived by the Institutional Review Board.
Patient selection
Using International Classification of Diseases-9/10 (ICD-9/10) and current procedural terminology (CPT) codes, adults aged 18 years or older diagnosed with either AS or DISH who underwent posterior spinal fusion surgery following cervical or noncervical fractures spinal fractures within the past twenty years were identified. Only primary fractures and posterior fusions were included. Fractures must have occurred within 3 months prior to the posterior fusion surgery. To remove potentially staged procedures, patients with an anterior approach fusion within 3 months before or after the index posterior event were excluded. Patients were divided into cohorts based on hyperostotic pathology and fracture location (cervical vs. noncervical fractures). Due to limitations in cohort size, thoracic and lumbar fractures were grouped together.
A total of 753 AS patients with fractures and 806 DISH patients with fractures were included. To minimize baseline variability between groups, propensity score matching (1:1) was performed based on age at index surgery, obesity, nicotine dependence, diabetes mellitus, presence of chronic obstructive pulmonary disease (COPD), gender, and race. TriNetX utilizes a greedy nearest-neighbor matching system with a 0.1 caliper width. Missing data was excluded from analysis, and patients lost to follow-up were excluded at analysis of that specific time point.
Outcome measures
Postoperative complications were evaluated at 3 months, 1 year, and 2 years following spinal fusion. Medical complications included thromboembolic events (both deep vein thrombosis and pulmonary embolism), urinary tract infection, and other medical events requiring emergency department (ED) visitation or inpatient management. Neurological complications such as cervical nerve root injury, limb paralysis, and spinal cord injury were also evaluated. Surgical complications included revision surgery, surgical site infection, wound complication, and instrumentation failure. Long term structural outcomes such as pseudoarthrosis and secondary cervical or lumbar fractures were collected when available. Mortality was assessed at all time points. All outcome coding were from prior published literature using the TriNetX database [[17], [18], [19]].
Statistical analysis
All statistical analyses were performed within the TriNetX platform using built-in analytical tools. Risk ratios were calculated for cervical versus noncervical fractures within the AS and DISH groups, as well as for AS compared with DISH across the fracture locations. Hazard ratio was calculated for mortality. A p-value < .05 was considered statistically significant for all comparisons.
Results
Demographics
Prior to matching, a total of 753 AS patients with fractures and 806 DISH patients with fractures were identified. Average age at index for AS patients was 68 (SD: 13.2) years old, 648 were male, and 615 were white. Of the 753 patients included, only 33 had an active prescription for adalimumab, 18 had a prescription for etanercept, and less than 10 had a prescription for golimumab or infliximab. Average age for DISH patients was 71.7 (10.9) years old, 692 were male, and 640 were white. Following 1:1 propensity score matching based on demographics and relevant risk factors, complete data was described for 576 AS and DISH patients. On average, the AS cohort was 68.0 ± 13.2 years old, 86.1% male, and 81.7% white. The DISH cohort was on average 71.7 ± 10.9 years old, 85.9% male, and 79.4% white. Patients were lost due to lack of follow-up available for all time points. Average follow up time at 90-days was 89 days for both groups, at 1-year was 350 days for both groups, and at 2-year was 678 days for AS patients and 703 days for DISH patients (Table 1).
Table 1.
Demographic.
| Variable | Pre-PSM |
Post-PSM |
p | SMD | ||
|---|---|---|---|---|---|---|
| AS (n = 753) | DISH (n = 806) | AS (n = 576) | DISH (n = 576) | |||
| Age at index | 68 ± 13.2 | 71.7 ± 10.9 | 69 ± 11 | 69 ± 10.6 | .93 | 0.005 |
| Male | 648 | 692 | 480 | 493 | .28 | 0.064 |
| Female | 98 | 113 | 91 | 77 | .24 | 0.069 |
| Hispanic or Latino | 30 | 40 | 25 | 21 | .55 | 0.036 |
| White | 615 | 640 | 458 | 460 | .8 | 0.009 |
| Black or AA | 55 | 75 | 47 | 49 | .83 | 0.013 |
| Hypertension | 373 | 483 | 307 | 308 | .95 | 0.004 |
| Diabetes mellitus | 251 | 371 | 221 | 217 | .81 | 0.014 |
| Hyperlipidemia | 244 | 342 | 217 | 214 | .85 | 0.01 |
| Heart failure | 143 | 168 | 119 | 118 | .94 | 0.004 |
| Obesity | 116 | 173 | 105 | 100 | .7 | 0.02 |
| Depression | 99 | 119 | 85 | 85 | 1 | < 0.001 |
| Anxiety | 98 | 112 | 82 | 77 | .67 | 0.025 |
| Chronic obstructive pulmonary disease | 89 | 97 | 68 | 71 | .79 | 0.016 |
| Nicotine dependence | 79 | 75 | 56 | 54 | .84 | 0.01 |
AS cervical versus noncervical fractures
At 3 months, cervical fractures were associated with significantly lower risk of surgical site infection (SSI) compared with noncervical fractures (RR 0.44, 95% CI 0.22–0.88, p = .016) (Table 2). At 3 months and 1-year, cervical fractures were associated with significantly lower risk of thromboembolic events (3 months: RR 0.48, 95% CI 0.24–0.96, p = .033; 1 year: RR 0.53, 95% CI 0.3–0.95, p = .03). At 1-year, cervical fractures were associated with significantly higher risk of repeat fracture (RR 1.95, 95% CI 1.01–3.75, p = .044). Lastly, at all-time points, cervical fractures were associated with significantly higher risk of spinal cord injury compared to noncervical fractures (3 months: RR 1.73, 95% CI 1.10–2.72, p = .015; 1 year: RR 1.53, 95% CI 1.03–2.28, p = .034; 2 years: RR 1.53, 95% CI 1.03–2.28, p = .034) (Table 3, Table 4, Table 5, Table 6, Table 7).
Table 2.
Propensity score matched inter-vertebral outcomes of all fractures in patients with AS.
| 3 mo AS |
p | ||||
|---|---|---|---|---|---|
| Variable | Cervical (N = 278) | Thoracic or lumbar (N = 278) | RR | 95% CI | |
| Revision surgery | 13 | 22 | 0.591 | 0.304, 1.15 | .12 |
| Surgical site infection | 11 | 25 | 0.44 | 0.221, 0.88 | .016 |
| Wound complication (dehiscence, infection, hematoma) | 14 | 24 | 0.58 | 0.31, 1.10 | .092 |
| Hardware failure | |||||
| ED visitation | 34 | 27 | 1.26 | 0.78, 2.03 | .34 |
| Mortality | 31 | 28 | 1.11 | 0.66, 1.84 | .7 |
| Spinal cord injury | 45 | 26 | 1.73 | 1.10,2.72 | .015 |
| Cervical root injury | 0 | 0 | |||
| Urinary tract infection | 29 | 26 | 1.12 | 0.68, 1.84 | .67 |
| Pseudoarthrosis | 28 | 23 | 1.22 | 0.72, 2.05 | .46 |
| Secondary cervical fracture | 11 | 13 | 1.65 | 0.76, 3.56 | .2 |
| Secondary lumbar fracture | |||||
| Medical complication | 38 | 49 | 0.78 | 0.53, 1.14 | .19 |
| Thrombotic event | 11 | 23 | 0.478 | 0.24, 0.96 | .033 |
| Limb paralysis | 34 | 31 | 1.1 | 0.70, 1.73 | .69 |
| 1-y AS | |||||
| Revision surgery | 13 | 22 | 0.591 | 0.304, 1.15 | .12 |
| Surgical site infection | 11 | 25 | 0.44 | 0.221, 0.88 | .016 |
| Wound complication (dehiscence, infection, hematoma) | 15 | 30 | 0.275, 0.91 | 0.5 | .02 |
| Hardware failure | |||||
| ED readmission | 49 | 43 | 1.14 | 7.9, 1.66 | .49 |
| Mortality | 41 | 38 | 1.09 | 0.70, 1.7 | .69 |
| Spinal cord injury | 52 | 34 | 1.53 | 1.03, 2.28 | .034 |
| Cervical root injury | 0 | 0 | |||
| Urinary tract infection | 39 | 32 | 1.22 | 0.79, 1.88 | .37 |
| Pseudoarthrosis | 32 | 28 | 1.14 | 0.71, 1.84 | .58 |
| Secondary cervical fracture | 16 | 16 | 1.95 | 1.01, 3.75 | .044 |
| Secondary lumbar fracture | |||||
| Medical complication | 44 | 56 | 0.79 | 0.55, 1.19 | .18 |
| Thrombotic event | 16 | 30 | 0.53 | 0.3, 0.95 | .03 |
| Limb paralysis | 40 | 33 | 1.2 | 0.79, 1.86 | .37 |
| 2-y AS | |||||
| Revision surgery | 13 | 22 | 0.591 | 0.3, 1.15 | .12 |
| Surgical site infection | 12 | 26 | 0.46 | 0.24, 0.90 | .019 |
| Wound complication (dehiscence, infection, hematoma) | 16 | 32 | 0.5 | 0.28, 0.89 | .016 |
| Hardware failure | < 10 | 13 | 0.77 | 0.34, 1.72 | .52 |
| ED readmission | 54 | 51 | 1.06 | 0.75, 1.49 | .74 |
| Mortality | 46 | 42 | 1.11 | 0.63, 1.69 | .63 |
| Spinal cord injury | 52 | 34 | 1.53 | 1.03, 2.28 | .034 |
| Cervical root injury | |||||
| Urinary tract infection | 41 | 31 | 1.32 | 0.86, 2.04 | .2 |
| Pseudoarthrosis | 34 | 31 | 1.097 | 0.70, 1.73 | .69 |
| Secondary cervical fracture | 16 | 20 | 1.55 | 0.84, 2.88 | .16 |
| Secondary lumbar fracture | |||||
| Medical complication | 47 | 63 | 0.75 | 0.54, 1.04 | .08 |
| Thrombotic event | 17 | 28 | 0.341, 1.079 | 0.34, 1.08 | .085 |
| Limb paralysis | 37 | 31 | 1.19 | 0.77, 1.86 | .43 |
AS, ankylosing spondylitis.
Table 3.
AS—propensity-score matched cervical versus thoracic only (N = 278).
| Variable | 3 mo |
1 y |
2 y |
||||||
|---|---|---|---|---|---|---|---|---|---|
| RR | 95% CI | p | RR | 95% CI | p | RR | 95% CI | p | |
| Revision surgery | 0.75 | 0.42, 1.35 | .34 | 0.81 | 0.47, 1.41 | .45 | 0.81 | 0.47, 1.4 | .45 |
| Surgical site infection | 0.58 | 0.3, 1.07 | .075 | 0.62 | 0.35, 1.09 | .095 | 0.61 | 0.35, 1.06 | .077 |
| Wound complication (dehiscence, infection, hematoma) | 0.73 | 0.43, 1.24 | .25 | 0.72 | 0.43, 1.20 | .2 | 0.73 | 0.44, 1.2 | .21 |
| Hardware failure | 1 | 0.44, 2.27 | 1 | 0.8 | 0.38, 1.68 | .55 | |||
| ED visitation | 0.97 | 0.61, 1.54 | .89 | 1.04 | 0.74, 1.46 | .83 | 0.94 | 0.63, 1.28 | .69 |
| Mortality | 1 | 0.63, 1.59 | 1 | 1.04 | 0.7, 1.51 | .82 | 1.06 | 0.75, 1.51 | .75 |
| Spinal cord injury | 1.02 | 0.69, 1.51 | .91 | 1.09 | 0.76, 1.56 | .66 | 1.06 | 0.74, 1.52 | .74 |
| Cervical root injury | |||||||||
| Urinary tract infection | 0.94 | 0.59, 1.49 | .79 | 1.15 | 0.78, 1.69 | .49 | 1.11 | 0.77, 1.60 | .58 |
| Pseudoarthrosis | 1 | 0.54, 1.85 | 1 | 0.87 | 0.53, 1.43 | .57 | 0.9 | 0.56, 1.47 | .68 |
| Secondary cervical fracture | 2.03 | 1.02, 4.05 | .04 | 2.17 | 1.16, 4.07 | .013 | 2.28 | 1.22, 4,2 | .008 |
| Secondary thoracic or lumbar fracture | |||||||||
| Medical complication | 0.9 | 0.64, 1.25 | .53 | 1 | 0.73, 1.36 | 1 | 1.01 | 0.76, 1.36 | .92 |
| Thrombotic event | 0.64 | 0.33, 1.22 | .17 | 0.79 | 0.44, 1.41 | .43 | 0.71 | 0.41, 1.24 | .23 |
| Limb paralysis | 0.7 | 0.47, 1.11 | .14 | 0.79 | 0.52, 1.17 | .23 | 0.76 | 0.51, 1.15 | .19 |
Table 4.
AS—propensity-score matched junctional versus nonjunctional outcomes (N = 201).
| Variable | 3 mo |
1 y |
2 y |
||||||
|---|---|---|---|---|---|---|---|---|---|
| RR | 95% CI | p | RR | 95% CI | p | RR | 95% CI | p | |
| Revision surgery | 1.63 | 0.79, 3.38 | .18 | 1.64 | 0.79, 3.38 | .17 | |||
| Surgical site infection | 1.55 | 0.74, 3.22 | .24 | 1.12 | 0.6, 2.09 | .73 | 1.17 | 0.64, 2.18 | .6 |
| Wound complication (dehiscence, infection, hematoma) | 1.57 | 0.83, 2.98 | .16 | 1.38 | 0.74, 2.5 | .31 | 1.44 | 0.78, 2.64 | .24 |
| Hardware failure | |||||||||
| ED visitation | 0.88 | 0.50, 1.5 | .64 | 0.9 | 0.61, 1.39 | .7 | 1.05 | 0.72, 1.51 | .81 |
| Mortality | 1.42 | 0.79, 2.56 | .25 | 1.46 | 0.88, 2.52 | .14 | 1.14 | 0.77, 1.74 | .52 |
| Spinal cord injury | 0.83 | 0.5, 1.37 | .46 | 0.88 | 0.56, 1.39 | .58 | 0.91 | 0.58, 1.43 | .68 |
| Cervical root injury | |||||||||
| Urinary tract infection | 1.26 | 0.72, 2.22 | .42 | 1.11 | 0.69, 1.8 | .67 | 1.21 | 0.77, 1.89 | .41 |
| Pseudoarthrosis | 1.64 | 0.79, 3.37 | .18 | 1.46 | 0.74, 2.87 | .27 | |||
| Medical complication | 1.62 | 1.07, 2.57 | .021 | 1.35 | 0.93, 1.97 | .11 | 1.2 | 0.85, 1.67 | .3 |
| Thrombotic event | 0.67 | 0.33, 1.35 | .25 | 0.75 | 0.4, 1.4 | .38 | 0.82 | 0.45, 1.48 | .5 |
| Limb paralysis | 2 | 1.09, 3.68 | .02 | 1.71 | 0.97, 3.0 | .059 | 1.77 | 1, 3.09 | .043 |
Table 5.
Propensity score matched inter-vertebral outcomes of all fractures in patients with DISH.
| 3 mo DISH |
p | ||||
|---|---|---|---|---|---|
| Variable | Cervical (N = 275) | Thoracic or lumbar (N = 275) | RR | 95% CI | |
| Revision surgery | Not enough | ||||
| Surgical site infection | 19 | 21 | 0.91 | 0.5, 1.65 | .74 |
| Wound complication (dehiscence, infection, hematoma) | 23 | 25 | 0.92 | 0.54, 1.58 | .76 |
| Hardware failure | Not enough | ||||
| ED admission | 34 | 38 | 0.9 | 0.58, 1.38 | .61 |
| Mortality | 30 | 22 | 1.38 | 0.80, 2.40 | .25 |
| Spinal cord injury | 55 | 22 | 2.5 | 1.57, 4.0 | < .001 |
| Cervical root injury | 0 | 0 | |||
| Urinary tract infection | 31 | 40 | 0.78 | 0.5, 1.2 | .25 |
| Pseudoarthrosis | 18 | 18 | 1 | 0.53, 1.88 | 1 |
| Medical complication | 41 | 55 | 0.75 | 0.52, 1.08 | .12 |
| Thrombotic event | 15 | 25 | 0.6 | 0.32, 1.11 | .1 |
| Limb paralysis | 35 | 15 | 2.33 | 1.3, 4.17 | .003 |
| 1-y DISH | |||||
| Revision surgery | 11 | 13 | 0.85 | 0.39, 1.86 | .68 |
| Surgical site infection | 22 | 20 | 1.1 | 0.62, 1.97 | .75 |
| Wound complication (dehiscence, infection, hematoma) | 22 | 26 | 0.85 | 0.49, 1.46 | .55 |
| Hardware failure | Not enough | ||||
| ED admission | 51 | 53 | 0.96 | 0.68, 1.36 | .83 |
| Mortality | 42 | 28 | 1.55 | 0.96, 2.5 | .07 |
| Spinal cord injury | 60 | 28 | 2.14 | 1.41, 3.25 | < .001 |
| Cervical root injury | 0 | 0 | |||
| Urinary tract infection | 41 | 43 | 0.95 | 0.64, 1.41 | .81 |
| Pseudoarthrosis | 24 | 22 | 1.09 | 0.63, 1.90 | .76 |
| Medical complication | 48 | 49 | 0.98 | 0.68, 1.41 | .91 |
| Thrombotic event | 22 | 24 | 0.92 | 0.53, 1.59 | .76 |
| Limb paralysis | 41 | 7 | 2.41 | 1.41, 4.14 | < .001 |
| 2-y DISH | |||||
| Revision surgery | 11 | 14 | 0.79 | 0.36, 1.7 | .54 |
| Surgical site infection | 22 | 23 | 0.96 | 0.55, 1.68 | .88 |
| Wound complication (dehiscence, infection, hematoma) | 25 | 27 | 0.93 | 0.55, 1.56 | .77 |
| Hardware failure | Not enough | ||||
| ED admission | 66 | 68 | 0.97 | 0.72, 1.31 | .84 |
| Mortality | 47 | 37 | 1.3 | 0.85, 2.01 | .23 |
| Spinal cord injury | 59 | 26 | 2.27 | 1.47, 3.50 | < .001 |
| Cervical root injury | 0 | 0 | |||
| Urinary tract infection | 43 | 50 | 0.86 | 0.59, 1.25 | .43 |
| Pseudoarthrosis | 24 | 22 | 1.09 | 0.63, 1.90 | .76 |
| Medical complication | 52 | 64 | 0.81 | 0.59, 1.13 | .21 |
| Thrombotic event | 22 | 28 | 0.79 | 0.46, 1.34 | .37 |
| Limb paralysis | 39 | 17 | 2.29 | 1.33, 3.96 | .0019 |
DISH, diffuse idiopathic skeletal hyperostosis.
Table 6.
DISH—propensity-score matched cervical versus thoracic only (N = 275).
| Variable | 3 mo |
1 y |
2 y |
||||||
|---|---|---|---|---|---|---|---|---|---|
| RR | 95% CI | p | RR | 95% CI | p | RR | 95% CI | p | |
| Revision surgery | 0.82 | 0.41, 1.65 | .58 | 0.88 | 0.45, 1.74 | .71 | |||
| Surgical site infection | 0.96 | 0.54, 1.69 | .88 | 0.92 | 0.52, 1.61 | .76 | 0.82 | 0.48, 1.4 | .47 |
| Wound complication (dehiscence, infection, hematoma) | 0.91 | 0.57, 1.46 | .69 | 0.91 | 0.58, 1.44 | .7 | 0.83 | 0.53, 1.28 | .39 |
| Hardware failure | |||||||||
| ED visitation | 1.22 | 0.85, 1.76 | .28 | 1.1 | 0.82, 1.46 | .52 | 1.08 | 0.84, 1.39 | .55 |
| Mortality | 1.44 | 0.94, 2.2 | .09 | 1.42 | 1, 2.02 | .049 | 1.5 | 1.07, 2.1 | .017 |
| Spinal cord injury | 1.93 | 1.35, 2.74 | < .001 | 1.78 | 1.27, 2.49 | < .001 | 1.8 | 1.29, 2.52 | < .001 |
| Cervical root injury | |||||||||
| Urinary tract infection | 1.3 | 0.85, 2 | .23 | 1.29 | 0.9, 1.85 | .17 | 1.22 | 0.87, 1.71 | .26 |
| Pseudoarthrosis | 1.07 | 0.54, 2.13 | .85 | 1.4 | 0.77, 2.58 | .26 | 1.26 | 0.7, 2.27 | .43 |
| Secondary cervical fracture | 3.3 | 1.65, 6.4 | < .001 | 2.99 | 1.55, 5.76 | .006 | |||
| Secondary thoracic or lumbar fracture | |||||||||
| Medical complication | 0.92 | 0.65, 1.29 | .61 | 0.83 | 0.61, 1.11 | .22 | 0.81 | 0.61, 1.08 | .14 |
| Thrombotic event | 0.75 | 0.45, 1.25 | .27 | 0.83 | 0.53, 1.32 | .44 | 0.85 | 0.55, 1.31 | .46 |
| Limb paralysis | 2.21 | 1.32, 3.72 | < .001 | 2.27 | 1.41, 3.67 | < .001 | 2.32 | 1.44, 3.74 | < .001 |
Table 7.
DISH—propensity-score matched junctional versus nonjunctional outcomes (N = 231).
| Variable | 3 mo |
1 y |
2 y |
||||||
|---|---|---|---|---|---|---|---|---|---|
| RR | 95% CI | p | RR | 95% CI | p | RR | 95% CI | p | |
| Revision surgery | |||||||||
| Surgical site infection | 0.83 | 0.43, 1.61 | .59 | 0.94 | 0.5, 1.78 | .5, 1.78 | 0.95 | 0.51, 1.76 | .86 |
| Wound complication (dehiscence, infection, hematoma) | 0.74 | 0.41, 1.34 | .32 | 0.96 | 0.55, 1.66 | .88 | 1 | 0.58, 1.73 | 1 |
| Hardware failure | |||||||||
| ED visitation | 0.96 | 0.58, 1.61 | .88 | 0.77 | 0.53, 1.13 | .18 | 0.8 | 0.57, 1.11 | .18 |
| Mortality | 1.07 | 0.53, 2.16 | .93 | 0.9 | 0.52, 1.56 | .63 | 0.93 | 0.56, 1.55 | .62 |
| Spinal cord injury | 1.26 | 0.76, 2.11 | .37 | 1.48 | 0.9, 2.42 | .12 | 1.64 | 1, 2.69 | .049 |
| Cervical root injury | |||||||||
| Urinary tract infection | 1.053 | 0.58, 1.92 | .87 | 0.73 | 0.42, 1.28 | .26 | 0.844 | 0.52, 1.36 | .48 |
| Pseudoarthrosis | 1.25 | 0.60, 2.61 | .55 | ||||||
| Medical complication | 1.2 | 0.77, 1.88 | .43 | 1.06 | 0.7, 1.59 | 1.06 | 1.02 | 0.71, 1.48 | .91 |
| Thrombotic event | 1.19 | 0.63, 2.25 | .6 | 1 | 0.55, 1.8 | 1 | 1.28 | 0.71, 2.3 | .82 |
| Limb paralysis | 0.92 | 0.43, 1.98 | .84 | 0.72 | 0.36, 1.44 | .35 | |||
A sensitivity analysis was performed comparing cervical versus thoracic fractures only, and similar findings were seen. Cervical fractures were associated with a nonsignificant decreased risk of SSI was seen at 3-months (RR 0.58, 95% CI 0.3–1.07, p = .075), and 1-year (RR 0.62, 95% CI 0.35–1.09, p = .095). Cervical fractures were also associated with a nonsignificant decrease in thrombotic events at 3-months (RR 0.64, 95% CI 0.33–1.22, p = .17) and 1-year (RR 0.79, 95% CI 0.44–1.41, p = .43), and associated with a significantly increased risk of subsequent cervical fracture at all time points.
A subanalysis was also performed reviewing junctional versus nonjunctional fractures by identifying patients with fractures in 2 adjacent vertebral segments (eg cervical and thoracic or thoracic and lumbar). Notably, junctional fractures were associated with a significantly higher risk of medical complications (RR 1.62, 95% CI 1.07–2.57, p = .021) at 3 months, and significantly higher risk of limb paralysis at all time points.
DISH cervical versus noncervical fractures
At all-time points, cervical fractures were associated with significantly higher risk of spinal cord injury (3 months: RR 2.5, 95% CI 1.57–4.00 p < .001; 1 year: RR 2.14, 95% CI 1.41–3.25, p < .001; 2 years: RR 2.27, 95% CI 1.47–3.50, p < .001) and significantly higher risk of limb paralysis at all time points (3 months: RR 2.33, 95% CI 1.3–4.17, p = .003; 1 year: RR 2.41, 95% CI 1.41–4.14, p < .001; 2 years: RR 2.29, 95% CI 1.33–3.96, p = .002).
A sensitivity analysis was performed reviewing cervical versus thoracic fractures only, and like results were found. Cervical fractures were associated with significantly higher risk of spinal cord injury and limb paralysis at all time points. Notably, on subanalysis, cervical fracture patients were associated with an increased risk of subsequent cervical fracture at 1-year (RR 3.3, 95% CI 1.65–6.4, p < .001) and 2-year (RR 2.99, 95% CI 1.55–5.76, p < .001).
A subanalysis comparing junctional versus nonjunctional injuries displayed no significant differences in outcomes, except a significant association with an increased risk of spinal cord injury at 2-years after injury within the junctional cohort (RR 1.64, 95% CI 1–2.69, p = .049). Results can be seen in Table 5.
AS versus DISH
At all-time points, patients with AS had significantly higher risk of mortality (3 months: RR 2.16, 95% CI 1.46–3.2, p < .001; 1 year: RR 1.77, 95% CI 1.30–2.40, p < .001; 2 years: RR 1.73, 95% CI 1.30–2.29, p < .001). At 3 months, patients with AS were associated with risk of subsequent surgery (RR 2.25, 95% CI 1.15–3.49, p = .015). At 1 year and 2 years, patients with AS were associated with increased risk of instrumentation failure (1 year: RR 2.27, 95% CI 1.13–4.60, p = .018; 2 years: RR 1.93, 95% CI 1.05–3.57, p = .032). Conversely, at 1 year and 2 years, patients with AS were associated with significantly lower risk of pseudoarthrosis (1 year: RR 0.58, 95% CI 0.39–0.86, p = .006; 2 years: RR 0.59, 95% CI 0.40–0.87, p = .007). Results can be seen in Table 8.
Table 8.
Postpropensity matched outcomes of all fractures in patients with DISH or ASK.
| 3 mo |
p | ||||
|---|---|---|---|---|---|
| Variable | ASK (n = 576) | DISH (n = 576) | OR | 95% CI | |
| Revision surgery | 27 | 12 | 2.25 | 1.15, | .015 |
| Surgical site infection | 36 | 36 | 1 | 0.64, 1.56 | 1 |
| Wound complication (dehiscence, infection, hematoma) | 52 | 42 | 1.24 | 0.84, 1.83 | .28 |
| Hardware failure | Not enough | ||||
| ED readmission | 74 | 76 | 0.97 | 0.72, 1.3 | .86 |
| Mortality | 77 | 37 | 2.16 | 1.46, 3.2 | < .001 |
| Cervical root injury | |||||
| Urinary tract infection | 75 | 68 | 1.14 | 0.83, 1.55 | .42 |
| Pseudoarthrosis | 29 | 44 | 0.66 | 0.42, 1.04 | .07 |
| Secondary cervical fracture | 19 | 22 | 0.82 | 0.45, 1.50 | .53 |
| Secondary lumbar fracture | |||||
| Medical complication | 118 | 103 | 1.15 | 0.9, 1.45 | .26 |
| Thrombotic event | 40 | 39 | 1.03 | 0.67, 1.57 | .91 |
| Limb paralysis | 63 | 48 | 1.31 | 0.92, 1.88 | .13 |
| 1-y | |||||
| Revision surgery | 34 | 24 | 1.42 | 0.85, 2.36 | .18 |
| Surgical site infection | 44 | 47 | 0.94 | 0.63, 1.39 | .74 |
| Wound complication (dehiscence, infection, hematoma) | 61 | 51 | 1.2 | 0.84, 1.71 | .32 |
| Hardware failure | 25 | 11 | 2.27 | 1.13, 4.6 | .018 |
| ED visitation | 103 | 113 | 0.91 | 0.72, 1.16 | .45 |
| Mortality | 112 | 66 | 1.77 | 1.30, 2.40 | < .001 |
| Spinal cord injury | 96 | 91 | 1.1 | 0.81, 1.37 | .69 |
| Cervical root injury | Not enough | ||||
| Urinary tract infection | 90 | 84 | 1.07 | 0.82, 1.41 | .62 |
| Pseudoarthrosis | 36 | 62 | 0.58 | 0.39, 0.86 | .006 |
| Secondary cervical fracture | 27 | 26 | 0.99 | 0.59, 1.67 | .97 |
| Secondary lumbar fracture | 17 | 13 | 1.48 | 0.74, 2.97 | .27 |
| Medical complication | 135 | 114 | 1.18 | 0.95, 1.48 | .13 |
| Thrombotic event | 53 | 50 | 1.06 | 0.73, 1.53 | .76 |
| Limb paralysis | 70 | 55 | 1.27 | 0.911, 1.78 | .15 |
| 2-y | |||||
| Revision surgery | 36 | 27 | 1.33 | 0.82, 2.17 | .24 |
| Surgical site infection | 45 | 50 | 0.9 | 0.61, 1.33 | .59 |
| Wound complication (dehiscence, infection, hematoma) | 62 | 53 | 1.17 | 0.83, 1.66 | .38 |
| Hardware failure | 29 | 15 | 1.93 | 1.05, 3.57 | .032 |
| ED readmission | 122 | 139 | 0.88 | 0.71, 1.09 | .24 |
| Mortality | 127 | 77 | 1.73 | 1.3, 2.29 | < .001 |
| Spinal cord injury | 96 | 93 | 1.03 | 0.79, 1.34 | .81 |
| Urinary tract infection | 91 | 95 | 1.04 | 0.80, 1.36 | .75 |
| Pseudoarthrosis | 37 | 63 | 0.59 | 0.40, 0.87 | .0065 |
| Secondary cervical fracture | 28 | 27 | 0.99 | 0.59, 1.65 | .97 |
| Secondary lumbar fracture | 17 | 14 | 1.38 | 0.70, 2.72 | .36 |
| Medical complication | 146 | 123 | 1.19 | 0.96, 1.47 | .11 |
| Thrombotic event | 56 | 51 | 1.1 | 0.77, 1.57 | .61 |
| Limb paralysis | 71 | 57 | 1.25 | 0.9,0, 1.73 | .19 |
DISH, diffuse idiopathic skeletal hyperostosis; ASK, ankylosing spondylitis.
Discussion
In this propensity scorematched cohort study of patients with AS or DISH undergoing spinal fusion for cervical or noncervical fractures, several important differences in postoperative outcomes based on both hyperostotic pathology and fracture location were identified. Cervical fractures were associated with a significantly higher risk of neurologic complications in both disorders. Additionally, AS was associated with significantly greater risk of mortality and instrumentation failure, while DISH was associated with higher long-term risk of pseudoarthrosis.
Regional differences: cervical versus noncervical fractures
In both AS and DISH cohorts, cervical fractures were associated with a significantly increased risk of spinal cord injury (SCI) compared to noncervical fractures at all time points. Most acute spinal fractures in patients with ADs occur in the subaxial cervical spine, particularly at C5-C6 and C6-C7 [5,20,21]. This region is especially susceptible due to a relatively narrow canal diameter [5,15,20]. As a result, even marginally displaced fractures can compromise the spinal cord and lead to damage [15]. Additionally, diagnosis of cervical fractures is often delayed due to nonspecific presentation and relatively low radiographic sensitivity [20,22]. Our findings shows that SCI risk persists beyond the immediate postoperative period and supports a low threshold for obtaining advanced imaging in AD patients with possible cervical spine injury, as well as heightened postoperative monitoring.
Interestingly, peri‑operative complications differed between AS and DISH patients, which may be reflective of the different comorbidity profiles correlated with these pathologies. AS is a well-known B27-related autoimmune condition commonly associated with poor wound healing and subsequent complications such as infection or dehiscence [[23], [24], [25]]. The exact mechanism for higher thromboembolic events has yet to be clearly defined within AS patients. However, a link between elevated inflammatory cytokines correlating with hyperstimulation of the coagulation cascade has been postulated [26,27]. Both findings point towards further research into peri‑operative management of patients regarding wound care, antibiotic use, and thromboembolic prophylaxis.
In the DISH cohort, patients with cervical fractures had significantly higher risk of limb paralysis compared to patients with noncervical fractures. Literature has highlighted how delayed detection of cervical fractures within DISH patients specifically have led to worse neurologic outcomes [[28], [29], [30]]. Our findings support prior findings and indicate a need for advanced imaging for any cervical trauma in DISH patients, while a noncervical fractures injury may warrant further work-up on a case-by-case basis.
Differences in outcomes between AS and DISH
Our findings add to the mixed data regarding differences in mortality between AS and DISH [5,11,31,32]. A possible explanation for the observed difference in mortality is the distinct comorbidity profiles of the 2 conditions. AS is an inflammatory spondyloarthropathy associated with restricted pulmonary physiology, cardiovascular disease, and osteoporosis, all of which can magnify surgical stress [[33], [34], [35], [36], [37], [38], [39]]. In contrast, DISH is linked to metabolic comorbidities like obesity and diabetes, which are clinically relevant but may not affect the cardiopulmonary reserve as strongly postoperatively [40]. Alternatively, fracture location may play a large role. Schoenfeld et al. emphasized the high risk of morbidity in cervical fractures, even within their smaller sample size [24]. Within our study cohorts, there were over 100 cervical fractures noted within the AS patient sample, likely contributing to the exorbitantly high mortality rates within the group. Our study however is limited by the lack of detail regarding etiology of trauma. With an inherent risk of fracture within this patient group, future research on how mechanism of injury impacts outcomes may help clarify the varying mortality rates seen in the literature. Pharmacologic differences may also play a role. Treatment of AS has evolved to include tumor necrosing factor (TNF)-alpha inhibitors, which may increase risk for immunity and overall health by decreasing the inflammatory cascade and cytokine production. However, past studies have been mixed on the actual effects of TNF-alpha inhibitors on wound healing. For instance, a meta-analysis performed by Xu et al. looking at risk of infection in patients with AS or spondyloarthritis found a nonsignificant increase in risk of infection, indicating potential bias within their studies [41]. A meta-analysis performed by Liu et al. also found there was an overall significant increase in patients using TNF-alpha inhibitors within elective orthopaedic surgery, but many individual studies included did not see a difference, and the effect was typically seen only in patients with preoperative TNF-alpha usage [42]. As noted within their article, there was a lack of randomized prospective studies on the topic, and available research has been performed within a rheumatoid arthritis population—which at baseline may have an increased risk for infection than the ankylosing spondylitis patient population. Due to the limited research, the role of TNF-alpha on outcomes cannot be ascertained, especially within the current study where a limited group of patients had an active prescription at any time prior to the index operation.
AS patients further exhibited higher rates of instrumentation failure at 1 and 2 years compared to DISH patients. This difference is likely attributable to the biomechanical and physiologic characteristics of AS. AS is associated with severe osteoporosis and long-segment ankylosis [38]. This can reduce the ability to securely anchor spinal implants and dissipate physiologic loads. In contrast, DISH often presents with more localized anterior ossification and relatively preserved posterior elements, resulting in a less globally fused spine that can distribute forces more favorably than in AS [2]. This finding suggests a need for research reviewing preoperative and intraoperative optimization for AS patients for improved instrumentation stability.
DISH patients were found to have significantly higher rates of pseudoarthrosis compared with AS patients at 1 year and 2 years in the combined noncervical fractures cohorts, likely related to the metabolic comorbidities associated with DISH, such as obesity and diabetes, which are known to impair bone healing [40]. Notably, GLP-1 agonists are commonly prescribed to address these common comorbidities. Research regarding the impact of this medication and how it interacts with the pathology of DISH postoperatively may be worthwhile to see how it affects bony outcomes.
Study limitations
This study contains several limitations. First, clinical details such as mechanism of injury, surgical approach, and fracture morphology are not evaluated in the dataset and can impact surgical outcomes, and thus our study is limited to an association rather than any causal relationship or conclusion between pathology and outcomes reported. The power of the analysis is dependent on the accuracy of billing codes, and miscoding or noncoding by providers are potential sources of error. DISH and AS can easily be mistaken on x-ray, CT, or MRI, and thus creates room for interobserver error—which cannot be accounted for within the current study. To best amend this problem, groups were created by excluding those with any future or prior diagnosis of the other pathology at any time point (eg if diagnosed with DISH they cannot have any diagnosis of AS in their chart either before or after index event, and vice-versa).
Additionally, the nature of the TriNetX database does not clearly illustrate which patients were lost to follow-up versus which simply had delayed follow-up. Although 1:1 propensity score matching was performed, unmeasured confounders may still be present. There has been an increased trend towards percutaneous pedicle screws for the management of thoracic and lumbar stiff spine fractures, and those details are not captured in the TrinetX database [13,[43], [44], [45]]. Lastly, the data does not include information about airway management and intubation difficulties during surgery, which is a known issue in AD patients and can contribute to morbidity or mortality [46,47]. Thus, external validity of our findings is limited.
Conclusion
In this study, fracture location and underlying AD were found to be correlated with postoperative outcomes after spinal fusion. Cervical fractures in both AS and DISH patients showed a higher risk of SCI compared to noncervical fractures, demonstrating the vulnerability of the ankylosed cervical spine. Overall, AS patients had higher rates of mortality, instrumentation failure, and wound complications compared to those with DISH, while DISH patients had higher rates of pseudoarthrosis. These differences highlight the distinct biomechanical characteristics of each disorder and the importance of considering pathology and fracture site when treating and counseling patients. Further investigation incorporating imaging and surgical variables is needed to better understand the mechanisms behind these outcomes and guide surgical decision making.
Data availability statement
Data is available upon reasonable request to the corresponding author.
Author contributions
Authors A.M, L.L, T.Q contributed to curation and supervision of the study. Authors M.S, K.Y, M.E, V.B, J.P.J completed data collection/analysis and manuscript formulation. All Authors (M.S, K.Y, M.E, T.Q, V.B, L.L, J.P.J, A.M) supported editing and submission of the study.
Declaration of competing interests
Addisu Mesfin following conflict of interest: Grants from Nuvasive, OREF grant, Depuy speaking fees, Globus consulting. The remaining co-authors have no conflict of interest to declare.
Funding
No funding was received for this paper.
Footnotes
FDA device/drug status: Not applicable.
Author disclosures: KY: Nothing to disclose. MS: Nothing to disclose. TQ: Nothing to disclose. VB: Nothing to disclose. LL: Nothing to disclose. CB: Nothing to disclose. ME: Nothing to disclose. JPJ: Nothing to disclose. AM: Grants: Nuvasive (Level A), OREF (Level A); Consulting: GS Medical (Level A), Globus (Level A), Medtronic (Level A), OREF (Level A), Nuvasive (Level A).
References
- 1.Braun J., Sieper J. Ankylosing spondylitis. Lancet. 2007;369(9570):1379–1390. doi: 10.1016/S0140-6736(07)60635-7. [DOI] [PubMed] [Google Scholar]
- 2.Resnick D., Niwayama G. Radiographic and pathologic features of spinal involvement in diffuse idiopathic skeletal hyperostosis (DISH) Radiology. 1976;119(3):559–568. doi: 10.1148/119.3.559. [DOI] [PubMed] [Google Scholar]
- 3.Dursun N., Sarkaya S., Ozdolap S., et al. Risk of falls in patients with ankylosing spondylitis. J Clin Rheumatol. 2015;21(2):76–80. doi: 10.1097/RHU.0000000000000216. [DOI] [PubMed] [Google Scholar]
- 4.Vergara M.E., O'Shea F.D., Inman R.D., Gage W.H. Postural control is altered in patients with ankylosing spondylitis. Clin Biomech (Bristol) 2012;27(4):334–340. doi: 10.1016/j.clinbiomech.2011.10.016. [DOI] [PubMed] [Google Scholar]
- 5.Westerveld L.A., Verlaan J.J., Oner F.C. Spinal fractures in patients with ankylosing spinal disorders: a systematic review of the literature on treatment, neurological status and complications. Eur Spine J. 2009;18(2):145–156. doi: 10.1007/s00586-008-0764-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Einsiedel T., Schmelz A., Arand M., et al. Injuries of the cervical spine in patients with ankylosing spondylitis: experience at two trauma centers. J Neurosurg Spine. 2006;5(1):33–45. doi: 10.3171/spi.2006.5.1.33. [DOI] [PubMed] [Google Scholar]
- 7.Hunter T., Forster B., Dvorak M. Ankylosed spines are prone to fracture. Can Fam Physician. 1995;41:1213–1216. [PMC free article] [PubMed] [Google Scholar]
- 8.Whang P.G., Goldberg G., Lawrence J.P., et al. The management of spinal injuries in patients with ankylosing spondylitis or diffuse idiopathic skeletal hyperostosis: a comparison of treatment methods and clinical outcomes. J Spinal Disord Tech. 2009;22(2):77–85. doi: 10.1097/BSD.0b013e3181679bcb. [DOI] [PubMed] [Google Scholar]
- 9.Broom M.J., Raycroft J.F. Complications of fractures of the cervical spine in ankylosing spondylitis. Spine (Phila Pa 1976) 1988;13(7):763–766. doi: 10.1097/00007632-198807000-00009. [DOI] [PubMed] [Google Scholar]
- 10.Einsiedel T., Kleimann M., Nothofer W., Neugebauer R. [Special considerations in therapy of injuries of the cervical spine in ankylosing spondylitis (Bechterew disease)] Unfallchirurg. 2001;104(12):1129–1133. doi: 10.1007/s001130170003. [DOI] [PubMed] [Google Scholar]
- 11.Bernstein D.N., McCalla D.J., Molinari R.W., Rubery P.T., Menga E.N., Mesfin A. An analysis of patient and fracture characteristics and clinical outcomes in patients with hyperostotic spine fractures. Global Spine J. 2020;10(8):964–972. doi: 10.1177/2192568219887157. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Rustagi T., Drazin D., Oner C., et al. Fractures in spinal ankylosing disorders: a narrative review of disease and injury types, treatment techniques, and outcomes. J Orthop Trauma. 2017;31(Suppl 4):S57–S74. doi: 10.1097/BOT.0000000000000953. [DOI] [PubMed] [Google Scholar]
- 13.Lawlor M., Botros M., Cady-McCrea C., et al. Percutaneous versus open management of thoracic and lumbar hyperostotic fractures: a case-control study. Cureus. 2025;17(10) doi: 10.7759/cureus.94737. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Kurucan E., Bernstein D.N., Mesfin A. Surgical management of spinal fractures in ankylosing spondylitis. J Spine Surg. 2018;4(3):501. doi: 10.21037/jss.2018.06.15. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15.Hartmann S., Tschugg A., Wipplinger C., Thome C. Analysis of the literature on cervical spine fractures in ankylosing spinal disorders. Global Spine J. 2017;7(5):469–481. doi: 10.1177/2192568217700108. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Hiyama A., Katoh H., Sakai D., Sato M., Tanaka M., Watanabe M. Prevalence of diffuse idiopathic skeletal hyperostosis (DISH) assessed with whole-spine computed tomography in 1479 subjects. BMC Musculoskelet Disord. 2018;19(1):178. doi: 10.1186/s12891-018-2108-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Dhodapkar M.M., Halperin S.J., Day W., et al. Outcomes following single level posterior lumbar fusion in patients with systemic and discoid lupus: a retrospective national database study. N Am Spine Soc J. 2025;22 doi: 10.1016/j.xnsj.2025.100604. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Garcia D., Sayegh J., Michael B.R., et al. Postoperative complications of single-level lumbar spine fusion in patients with preoperative vitamin D deficiency: a retrospective cohort study. Global Spine J. 2025 doi: 10.1177/21925682251386808. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.McDonald C.L., Hershman S.H., Hogan W., et al. Cervical laminoplasty versus posterior laminectomy and fusion: trends in utilization and evaluation of complication and revision surgery rates. J Am Acad Orthop Surg. 2022;30(17):858–866. doi: 10.5435/JAAOS-D-22-00106. [DOI] [PubMed] [Google Scholar]
- 20.Chaudhary S.B., Hullinger H., Vives M.J. Management of acute spinal fractures in ankylosing spondylitis. ISRN Rheumatol. 2011;2011 doi: 10.5402/2011/150484. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Caron T., Bransford R., Nguyen Q., Agel J., Chapman J., Bellabarba C. Spine fractures in patients with ankylosing spinal disorders. Spine (Phila Pa 1976) 2010;35(11):E458–E464. doi: 10.1097/BRS.0b013e3181cc764f. [DOI] [PubMed] [Google Scholar]
- 22.Anwar F., Al-Khayer A., Joseph G., Fraser M.H., Jigajinni M.V., Allan D.B. Delayed presentation and diagnosis of cervical spine injuries in long-standing ankylosing spondylitis. Eur Spine J. 2011;20(3):403–407. doi: 10.1007/s00586-010-1628-y. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23.Pesenti S., Pannu T., Andres-Bergos J., et al. What are the risk factors for surgical site infection after spinal fusion? A meta-analysis. Eur Spine J. 2018;27(10):2469–2480. doi: 10.1007/s00586-018-5733-7. [DOI] [PubMed] [Google Scholar]
- 24.Zhou J., Wang R., Huo X., Xiong W., Kang L., Xue Y. Incidence of surgical site infection after spine surgery: a systematic review and meta-analysis. Spine (Phila Pa 1976) 2020;45(3):208–216. doi: 10.1097/BRS.0000000000003218. [DOI] [PubMed] [Google Scholar]
- 25.Gephart M.G., Zygourakis C.C., Arrigo R.T., Kalanithi P.S., Lad S.P., Boakye M. Venous thromboembolism after thoracic/non-cervical fractures spinal fusion. World Neurosurg. 2012;78(5):545–552. doi: 10.1016/j.wneu.2011.12.089. [DOI] [PubMed] [Google Scholar]
- 26.Ungprasert P., Srivali N., Kittanamongkolchai W. Ankylosing spondylitis and risk of venous thromboembolism: a systematic review and meta-analysis. Lung India. 2016;33(6):642–645. doi: 10.4103/0970-2113.192862. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27.Ogdie A., Kay McGill N., Shin D.B., et al. Risk of venous thromboembolism in patients with psoriatic arthritis, psoriasis and rheumatoid arthritis: a general population-based cohort study. Eur Heart J. 2018;39(39):3608–3614. doi: 10.1093/eurheartj/ehx145. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 28.Saito R., Onishi E., Mitsuzawa S., et al. Association between trauma-induced vertebral fractures and motor weakness in patients with diffuse idiopathic skeletal hyperostosis. Cureus. 2024;16(12) doi: 10.7759/cureus.76403. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 29.Tsuji O., Suda K., Takahata M., et al. Early surgical intervention may facilitate recovery of cervical spinal cord injury in DISH. J Orthop Surg (Hong Kong) 2019;27(1) doi: 10.1177/2309499019834783. [DOI] [PubMed] [Google Scholar]
- 30.Katoh H., Okada E., Yoshii T., et al. A comparison of cervical and non-cervical fractures fractures associated with diffuse idiopathic skeletal hyperostosis: a nationwide multicenter study. J Clin Med. 2020;9(1) doi: 10.3390/jcm9010208. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 31.Chen S.R., Munsch M.A., Chen J., et al. Spine fractures of patients with ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis: fracture severity and injury-related mortality at a level I trauma center. Asian Spine J. 2023;17(3):549–558. doi: 10.31616/asj.2022.0155. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 32.Schoenfeld A.J., Harris M.B., McGuire K.J., Warholic N., Wood K.B., Bono C.M. Mortality in elderly patients with hyperostotic disease of the cervical spine after fracture: an age- and sex-matched study. Spine J. 2011;11(4):257–264. doi: 10.1016/j.spinee.2011.01.018. [DOI] [PubMed] [Google Scholar]
- 33.Dik V.K., Peters M.J., Dijkmans P.A., et al. The relationship between disease-related characteristics and conduction disturbances in ankylosing spondylitis. Scand J Rheumatol. 2010;39(1):38–41. doi: 10.3109/03009740903096101. [DOI] [PubMed] [Google Scholar]
- 34.Kazmierczak J., Peregud-Pogorzelska M., Biernawska J., et al. Cardiac arrhythmias and conduction disturbances in patients with ankylosing spondylitis. Angiology. 2007;58(6):751–756. doi: 10.1177/0003319707299208. [DOI] [PubMed] [Google Scholar]
- 35.Davies D. Ankylosing spondylitis and lung fibrosis. Q J Med. 1972;41(164):395–417. [PubMed] [Google Scholar]
- 36.Kanathur N., Lee-Chiong T. Pulmonary manifestations of ankylosing spondylitis. Clin Chest Med. 2010;31(3):547–554. doi: 10.1016/j.ccm.2010.05.002. [DOI] [PubMed] [Google Scholar]
- 37.Sil A.K. Lung changes in ankylosing spondylitis. Chest. 1972;61(4):406–407. doi: 10.1378/chest.61.4.406. [DOI] [PubMed] [Google Scholar]
- 38.Klingberg E., Lorentzon M., Mellstrom D., et al. Osteoporosis in ankylosing spondylitis: prevalence, risk factors and methods of assessment. Arthritis Res Ther. 2012;14(3) doi: 10.1186/ar3833. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 39.Momeni M., Taylor N., Tehrani M. Cardiopulmonary manifestations of ankylosing spondylitis. Int J Rheumatol. 2011;2011 doi: 10.1155/2011/728471. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 40.Terzi R. Extraskeletal symptoms and comorbidities of diffuse idiopathic skeletal hyperostosis. World J Clin Cases. 2014;2(9):422–425. doi: 10.12998/wjcc.v2.i9.422. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 41.Xu Z., Xu P., Fan W., et al. Risk of infection in patients with spondyloarthritis and akylosing spondylitis receiving antitumor necrosis factor therapy: a meta-analysis of randomized controlled trials. Exp Ther Med. 2017;14(4):3491–3500. doi: 10.3892/etm.2017.5003. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 42.Liu X., Wei C., Wang J., et al. Effect of tumour necrosis factor-a inhibitors exposure on surgical site infections in rheumatoid arthritis patients undergoing elective orthopaedic surgery: a meta-analysis. Int Wound J. 2024;21(1) doi: 10.1111/iwj.14538. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 43.Trungu S., Ricciardi L., Forcato S., Miscusi M., Raco A. Percutaneous instrumentation with cement augmentation for traumatic hyperextension thoracic and lumbar fractures in ankylosing spondylitis: a single-institution experience. Neurosurg Focus. 2021;51(4):E8. doi: 10.3171/2021.7.FOCUS21308. [DOI] [PubMed] [Google Scholar]
- 44.Kai K., Ikuta K., Masuda K., Kitamura T., Senba H., Shidahara S. Surgical outcomes of minimally invasive stabilization for spinal fractures in patients with ankylosing spinal disorders. Asian Spine J. 2018;12(3):434–441. doi: 10.4184/asj.2018.12.3.434. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 45.Yeoh D., Moffatt T., Karmani S. Good outcomes of percutaneous fixation of spinal fractures in ankylosing spinal disorders. Injury. 2014;45(10):1534–1538. doi: 10.1016/j.injury.2014.03.020. [DOI] [PubMed] [Google Scholar]
- 46.Mader R. Clinical manifestations of diffuse idiopathic skeletal hyperostosis of the cervical spine. Semin Arthritis Rheum. 2002;32(2):130–135. doi: 10.1053/sarh.2002.33726. [DOI] [PubMed] [Google Scholar]
- 47.Woodward L.J., Kam P.C. Ankylosing spondylitis: recent developments and anaesthetic implications. Anaesthesia. 2009;64(5):540–548. doi: 10.1111/j.1365-2044.2008.05794.x. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
Data is available upon reasonable request to the corresponding author.