Ankylosing spondylitis and spinal cord injury: origin, incidence, management, and avoidance

Decreasing incidence of cervical spine fractures in patients with ankylosing spondylitis: a population-based study in Southeast Norway

BACKGROUND CONTEXT

Individuals diagnosed with ankylosing spondylitis (AS) face an increased risk of spine fractures, specifically cervical spine fractures (CS-Fxs). In the past two decades, biological disease-modifying antirheumatic drugs (bDMARDs) have provided considerable relief from pain and an enhanced sense of wellbeing for a large segment of AS patients. Despite these improvements, it remains unclear whether extended use of bDMARDs can indeed reduce the risk of spine fractures.

PURPOSE

In this study, we aimed to investigate the evolving patterns and epidemiology of traumatic CS-Fxs in both AS and non-AS populations. We hypothesized that the risk of CS-Fxs among AS patients would show a decreasing trend over time, while the risk among non-AS patients would remain constant.

STUDY DESIGN/SETTING

Retrospective cohort study based on a prospective database.

PATIENT SAMPLE

A total of 3,598 consecutive patients with CS-Fxs were treated at Oslo University Hospital over an 8-year period.

OUTCOME MEASURES

CS-Fxs in AS patients were contrasted with non-AS-related CS-Fxs in terms of temporal trends, age, sex, injury mechanism, associated cervical spinal cord injury (cSCI), need for surgical fixation, and 30-day mortality.

METHODS

Data regarding all CS-Fxs diagnosed between 2015 and 2022 were extracted from the Southeast Norway population-based quality control database for traumatic CS-Fxs. Categorical data were summarized using frequencies, and continuous data were summarized using medians. The Wilcoxon rank-sum test was used to compare continuous variables, and the chi-squared test and Fischer exact test were used to compare categorical variables. To investigate the trend in the incidence of fractures, two different Poisson models were fitted with the number of non-AS and AS fractures as dependent variables and the year as the explanatory variable.

RESULTS

Over an 8-year period, we registered 3,622 CS-Fxs in 3598 patients, with AS patients accounting for 125 of these fractures. Relative to their non-AS counterparts, AS patients presented a 9-fold and 8-fold higher risk of initial and subsequent CS-Fxs, respectively. We observed a declining trend in AS-related CS-Fxs with an annual linear decrease of 8.4% (p=.026), whereas non-AS-related CS-Fxs showed an annual linear increase of 3.7% (p<.001). AS patients sustaining CS-Fxs were typically older (median age 70 vs 63 years), predominantly male (89% vs 67%), and more frequently experienced injuries due to falls (82% vs 57%). They also exhibited a higher prevalence of subaxial CS-Fxs (91% vs 62%), fewer C0-C2 CS-Fxs (14% vs 44%), a higher rate of associated cSCI (21% vs 11%), and a greater tendency for surgical fixation (66% vs 21%). We observed a 30-day mortality rate of 11% in AS patients and 5.4% in non-AS patients (p=.005).

CONCLUSIONS

The results of this study confirm the elevated risk of CS-Fxs among AS patients, although this risk appears to show a decreasing trend. The most plausible explanation for this risk reduction is the widespread application of bDMARDs.

Treatment of lower cervical spine fracture with ankylosing spondylitis by simple long anterior cervical plate: a retrospective study of 17 cases

Objective

Ankylosing spondylitis (AS), an autoimmune disease, often leads to lower cervical spine fractures, with the potential for severe spinal nerve damage even from low-energy injuries. The optimal treatment approach remains debated.

Methods

A retrospective study involved 17 AS patients with lower cervical spine fractures who received anterior cervical fixation. Most presented cervicothoracic or thoracolumbar kyphosis, with 11 exhibiting neurological deficits. Patient characteristics, clinical data, visual analog scale (VAS), complications, and nerve recovery were analyzed.

Results

No postoperative neurological deterioration occurred. All cases experienced complete fusion of fractures during the follow-up period. Preoperative VAS significantly decreased at 3 days and 3 months post-surgery. Of the 11 patients with preoperative neurological deficits, approximately 54.5% showed improvement post-surgery. No complications were reported, such as esophageal fistula, wound infection, or fixation failure.

Conclusion

Anterior internal fixation is a possible treatment for AS-related lower cervical fractures. This approach ensures satisfactory spinal stability and neurological recovery with proper cranial traction and external fixation post-surgery. Our findings demonstrate that this surgical method is safe and effective.

Comparison of Posterior Approach and Combined Anterior-Posterior Approach in the Treatment of Ankylosing Spondylitis Combined With Cervical Spine Fracture: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review.

OBJECTIVE

To compare the efficacy of the posterior approach and combined anterior-posterior approach in the treatment of ankylosing spondylitis (AS) with cervical spine fracture by meta-analysis.

METHODS

The databases PubMed, Web of Science, Embase, and Cochrane Library were searched for studies on the comparison of the posterior approach group and the combined anterior-posterior approach group in the treatment of ankylosing spondylitis combined with cervical spine fracture from database establishment to August 2023. The procedure time, intraoperative blood loss, the rates of neurological improvement, mean change in the postoperative neurological function, complication rates, rates of revised surgery, and mortality were extracted. Meta-analysis was performed using RevMan 5.4 software provided by Cochrane Library.

RESULTS

A total of 11 retrospective cohort studies with a total of 215 patients were included in this study. The posterior approach group had lower intraoperative blood loss than the combined anterior-posterior approach group [Mean difference (MD) = -146.05, 95%CI(-187.40,-104.69), P < .00001]; the operation time was significantly less in the posterior approach group than in the combined anterior-posterior approach group [MD = -95.34, 95%CI(-113.13,-77.55), P < .00001]. There were no statistically significant differences in the neurological improvement rates, mean changes in postoperative neurological function, complication rates, modified surgery rates, and mortality rates.

CONCLUSION

Both the posterior approach and combined anterior and posterior approach can achieve good results. Clinicians should develop an individualized approach based on the patient's fracture type, degree of spinal cord injury, fracture stability, fracture dislocation, general condition, and underlying disease.

Iatrogenic vertebral fracture in ankylosed spine during liver transplantation: a case report and biomechanical study using finite element method

PURPOSE

The occurrence of an iatrogenic vertebral fracture during non-spinal digestive surgery is an exceptional event that has not been previously documented. Our study aims to explain the occurrence of this fracture from a biomechanical perspective, given its rarity. Using a finite element model of the spine, we will evaluate the strength required to induce a vertebral fracture through a hyperextension mechanism, considering the structure of the patient's spine, whether it is ossified or healthy.

METHODS

A 70-year-old patient was diagnosed T12 fracture during a liver transplantation on ankylosed spine. We use a finite element model of the spine. Different mechanical properties were applied to the spine model: first to a healthy spine, the second to a osteoporotic ossified spine. The displacement and force imposed at the Sacrum, the time and location of fractures initiation were recorded and compared between the two spine conditions.

RESULTS

A surgical treatment is done associating decompression with posterior fixation. After biomechanical study, we found that the fracture initiation occurred for the ossified spine after a sacrum displacement of 29 mm corresponding to an applied force of 65 N. For the healthy spine it occurred at a sacrum displacement of 52 mm corresponding to an applied force of 350 N.

CONCLUSION

The force required to produce a type B fracture in an ankylosed spine is 5 times less than in a healthy spine. These data enable us to propose several points of management to avoid unexpected complications with ankylosed spines during surgical procedures.

LEVEL OF EVIDENCE

IV.

Construct length analysis of type B and C cervical and thoracolumbar fractures

Objectives

The purpose of this study is to identify if construct length affects the rate of surgical complications and instrumentation revision following surgical fixation of subaxial and thoracolumbar Type B and C fractures. This study evaluates the effect of ankylosing spondylitis/diffuse idiopathic skeletal hyperostosis (AS/DISH) within this population on outcomes.

Methods

Retrospective review of 91 cervical and 89 thoracolumbar Type B and C fractures. Groups were divided by construct length for analysis: short-segment (constructs spanning two or less segments adjacent to the fracture) and long-segment (constructs spanning more than two segments adjacent to the vertebral fracture).

Results

For cervical fractures, construct length did not impact surgical complications (P = 0.641), surgical hardware revision (P = 0.167), or kyphotic change (P = 0.994). For thoracolumbar fractures, construct length did not impact surgical complications (P = 0.508), surgical hardware revision (P = 0.224), and kyphotic change (P = 0.278). Cervical Type B fractures were nonsignificantly more likely to have worsened kyphosis (P = 0.058) than Type C fractures. Assessing all regions of the spine, a diagnosis of AS/DISH was associated with an increase in kyphosis (P = 0.030) and a diagnosis of osteoporosis was associated with surgical hardware failure (P = 0.006).

Conclusion

Patients with short-segment instrumentation have similar surgical outcomes and changes in kyphosis compared to those with long-segment instrumentation. A diagnosis of AS/DISH or osteoporosis was associated with worse surgical outcomes.

Concurrently Occurring Spinal Cord Cross-Section and Aortic Injury After a Chalk-Stick Fracture and Dislocation in Patient with Ankylosing Spondylitis: Clinical Image

A 74-year-old woman with ankylosing spondylitis presented with back pain and complete paraplegia after a fall. A radiologic finding of a bamboo spine, a characteristic feature of ankylosing spondylitis, was observed on computed tomography, along with a fracture-dislocation involving T10 and T11 (chalk-stick fracture) and compression of the descending thoracic aorta due to the caudal bony column. The patient underwent an open reduction and T8-L3 posterior fusion in the operating room. A complete cross-section of the spinal cord was observed during surgery. Post operation, a decrease in blood pressure led to a thoracotomy and thoracic endovascular aortic repair due to a crack in the descending aorta wall. Thoracolumbar fracture-dislocations, particularly in patients with ankylosing spondylitis, are characterized by instability and can be further complicated by concurrent vascular and spinal cord injuries. It is crucial therefore to recognize the potential for vascular and spinal cord injuries early on in such cases.

Management of Thoracolumbar Vertebral Fractures and Dislocations in Patients with Ankylosing Conditions of the Spine

Ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) are bone-forming spinal conditions which inherently increase spine rigidity and place patients at a higher risk for thoracolumbar fractures. Due to the long lever-arm associated with their pathology, these fractures are frequently unstable and may significantly displace leading to catastrophic neurologic consequences. Operative and non-operative management are considerations in these fractures. However conservative measures including immobilization and bracing are typically reserved for non-displaced or incomplete fractures, or in patients for whom surgery poses a high risk. Thus, first line treatment is often surgery which has historically been an open posterior spinal fusion. Recent techniques such as minimally invasive surgery (MIS) and robotic surgery have shown promising lower complication rates as compared to open techniques, however these methods need to be further validated.

Complications of the Rigid Spine

We present a short overview of the most common causes and imaging findings of a rigid spine including long-standing spondylarthritis, diffuse idiopathic skeletal hyperostosis, and the less common ossification of the posterior longitudinal ligament. The article also focuses on the pathogenesis and imaging findings of acute complications of the rigid spine due to fractures. These fractures may occur even after minor trauma and are difficult to detect on initial radiographs, resulting in a delayed diagnosis. They are often unstable with a high risk of severe neurologic complications, leading to high morbidity and mortality both in the initial phase and in the months following the fracture. Because the negative predictive value of conventional radiography is low, every patient with a rigid spine with newly appearing pain should be referred for subsequent cross-sectional imaging.

Screw fixation without fusion for low lumbar chance fracture accompanied by spinal epidural hematoma in patient with ankylosing spondylitis

Ankylosing spondylitis (AS) is a chronic inflammatory disease involving the sacroiliac joint and axial spine. AS may render the ankylosed spine prone to trauma and cause an increased frequency of associated epidural hematomas in spine fractures. Herein, we report a rare case of L5 chance fracture and epidural hematoma in a 27-year-old female patient with AS. She was treated surgically but without bone fusion or decompressive laminectomy due to the neurologically intact status despite significant neural compression by the spinal epidural hematoma (SEH). We believe that conservative treatment with close observation of neurological status may be effective in SEH presenting with mild neurological symptoms despite significant neural compression.

Risk factors for thirty-day morbidity and mortality after spinal trauma

BACKGROUND

Traumatic Spinal Injuries (TSI) often follow high velocity injuries and frequently accompanied by polytrauma. While most studies have focussed on outcomes of spinal cord injuries, the incidence and risk factors that predict morbidity and mortality after TSI has not been well-defined.

METHODS

Data of consecutive patients of TSI (n = 2065) treated over a 5-year-period were evaluated for demographics, injury mechanisms, neurological status, associated injuries, timing of surgery and co-morbidities. The thirty-day incidence and risk factors for complications, length of stay and mortality were analysed.

RESULTS

The incidence of spinal trauma was 6.2%. Associated injuries were seen in 49.7% (n = 1028), and 33.5% (n = 692) patients had comorbidities. The 30-day mortality was 0.73% (n = 15). Associated chest injuries (p = 0.0001), cervical spine injury (p = 0.0001), ASIA-A neurology (p < 0.01) and ankylosing spondylitis (p = 0.01) correlated with higher mortality. Peri-operative morbidity was noted in 571 patients (27.7%) and were significantly associated with age > 60 (p = 0.043), ASIA-A neurology (p < 0.05), chest injuries (p = 0.042), cervical and thoracic spine injury (p < 0.0001). The mean length of stay in hospital was 8.87 days. Cervical spine injury (p < 0.0001), delay in surgery > 48 h (p = 0.011), Diabetes mellitus (p = 0.01), Ankylosing spondylitis (p = 0.009), associated injuries of chest, head, pelvis and face (p < 0.05) were independent risk factors for longer hospital stay.

CONCLUSION

Key predictors of mortality after spinal trauma were cervical spine injury, complete neurological deficit, chest injuries and ankylosing spondylitis, while additionally higher age and thoracic injuries contributed to higher morbidity and prolonged hospitalisation. Notably multi-level injuries, higher age, co-morbidities and timing of surgery did not influence the mortality.

Combined anterior and posterior approach in treatment of ankylosing spondylitis-associated cervical fractures: a systematic review and meta-analysis

OBJECTIVE

Cervical fractures with ankylosing spondylitis (CAS) are a specific type of spinal fracture with poor stability, low healing rate, and high disability rate. Its treatment is mainly surgical, predominantly through the anterior approach, posterior approach, and the anterior-posterior approach. Although many clinical studies have been conducted on various surgical approaches, controversy still exists concerning the choice of these surgical approaches by surgeons. The authors present here a systematic evaluation and meta-analysis exploring the utility of the anterior-posterior approach versus the anterior approach and the posterior approach.

METHODS

After a comprehensive literature search of PubMed, Cochrane, Web of Science, and Embase databases, 12 clinical studies were included in the final qualitative analysis and 8 in the final quantitative analysis. Of these studies, 11 conducted a comparison between the anterior-posterior approach and the anterior approach and posterior approaches, while one examined only the anterior-posterior approach. Where appropriate, statistical advantage ratios and 95% confidence intervals were calculated.

RESULTS

The present meta-analysis of postoperative neurological improvement showed no statistical difference in the overall neurological improvement rate between the anterior-posterior approach and anterior approach (OR 1.70, 95% CI 0.61 to 4.75; p = 0.31). However, the mean change in postoperative neurological function was lower in patients who received the anterior approach than in those who received the anterior-posterior approach (MD 0.17, 95% CI -0.02 to 0.36; p = 0.08). There was an identical trend between the anterior-posterior approach and posterior approach, with no statistically significant difference in the overall rate of neurological improvement (OR 1.37, 95% CI 0.70 to 2.56; p = 0.38). Nevertheless, the mean change in neurological function was smaller in patients receiving the anterior-posterior approach compared with the posterior approach, but there was no statistically significant difference between the two (MD 0.17, 95% CI -0.02 to 0.36; p = 0.08).

CONCLUSIONS

The results of this review and meta-analysis suggest that the benefits of the anterior-posterior approach are different from those of the anterior and posterior approaches in the treatment of ankylosing spondylitis-related cervical fractures. In a word, there is no significant difference between the cervical surgical approach and the neurological functional improvement. Therefore, surgeons should pay more attention to the type of cervical fracture, the displacement degree of cervical fracture, the spinal cord injury, the balance of cervical spine and other aspects to comprehensively consider the selection of appropriate surgical methods.

Surgical treatment of thoracolumbar fracture in ankylosing spondylitis: A comparison of percutaneous and open techniques

BACKGROUND CONTEXT

Posterior percutaneous long-segment internal fixation and open fixation with long-segment screws have been used to treat thoracolumbar fractures in ankylosing spondylitis patients.

PURPOSE

To observe the clinical effect of posterior percutaneous long-segment internal fixation in 26 ankylosing spondylitis (AS) patients with thoracolumbar fractures.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

Forty-seven AS patients who were diagnosed with thoracolumbar fractures and treated from December 2014 to December 2018.

OUTCOME MEASURES

Visual analog scale score, Cobb angle, American Spinal Injury Association Grade, SF-Qualiveen score, pedicle screw misplacement rate, operative duration, blood loss, complications, bed rest duration and modified MacNab score.

METHODS

All patients were divided into the percutaneous group (PG) and the open group. Twenty-six patients were treated with percutaneous long-segment internal fixation, and the remaining 21 underwent open fixation with long-segment screws. The minimum follow-up period was 12 months.

RESULTS

The operations were successful in both groups. A patient in the PG showed class C wound healing, while the others showed class A healing, and some patients experienced perioperative complications. All patients were followed up for 12-48 months (mean, 33.81 months), and all patients showed clinical osseous fracture healing. Significant differences were found in operative duration, intraoperative blood loss and postoperative bed rest duration between the two groups (P < 0.05). No significant difference was found in improvement of the visual analog scale score, Cobb angle of spinal kyphosis or neurological function after the operation (P > 0.05).

CONCLUSIONS

As a minimally invasive procedure, posterior percutaneous long-segment internal fixation requires less time, results in less blood loss and causes less trauma. This procedure can also improve patients' pain, neurological function and kyphotic deformity and achieve effects similar to those of traditional methods. With this curative clinical effect, this procedure can be used as an ideal surgical treatment for thoracolumbar fractures in AS patients, especially for elderly patients with underlying diseases and high surgical risk.

Outcomes of spinal cord injury following cervical fracture in ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis (DISH): A prospective cohort study

INTRODUCTION

The ankylosed spine is prone to increased fractures risk even after minor trauma. The lower cervical spine is most frequently injured, and fractures of the ankylosed spine tend to precipitate spinal cord injury (SCI). The objective of the current study is to assess the incidence, management, and outcomes of patients with ankylosis of the spine sustaining a cervical fracture with associated SCI over a 7-year period.

MATERIAL AND METHODS

Prospective cohort study. Patients referred to the institution with a cervical fracture associated with SCI on a background of AS or DISH from 2009 to 2017 were reviewed. Demographics, mechanism of injury, fracture type, neurological level of injury, time to surgery, surgical management, neurological status (AIS), spinal cord independence measure (SCIMIII) scale at admission and discharge, and hospital length of stay. In September 2019 the summative data was analyzed using NDI, VAS, SV-QLI/SCI and length of survival were analyzed for statistical significance. Pathological fractures and dementia were excluded.

RESULTS

1613 patients with traumatic SCI were admitted in this period of whom 37 (12 AS and 25 DISH) met the inclusion criteria (mean age 65 years AS; 67 DISH). Fracture-dislocation was the most frequent fracture type (33% AS patients, 24% DISH patients). C4 was the most common neurological level of injury. SCIMIII score at admission was 1 point and 59 at discharge. AIS at admission was A (50%). At time of discharge no patient had neurologically deteriorated. Post-discharge mortality was 58% in AS patients and 32% in DISH patients (p=0.13).

CONCLUSIONS

Both AS and DISH patients have high levels of disability and mortality associated with trauma to the cervical spine. Despite their distinct clinical differences, in this cohort there were no statistically significant differences between AS and DISH patients regarding fracture type, SCIMIII, AIS, hospital stay, mortality, VAS, and SV-QLI/SCI after cervical fracture over 7 years follow-up.

Surgical Outcomes and Prognostic Factors for Cervical Spine Fractures in Patients with Ankylosing Spondylitis

BACKGROUND

Ankylosing spondylitis (AS) often results in progressive spinal stiffness, making patients prone to spinal fractures. Cervical spine fractures in AS mostly occur in the lower segment and cause progressive neurological deficits. However, the optimal approach to treating this patient population is still controversial, and it is unclear what factors have an impact on prognosis. Thus, this study aimed to investigate the choice of surgical approach and prognostic factors in AS patients with cervical spine fractures.

METHODS

A total of 22 AS patients with cervical fracture who were treated in our institution were reviewed from 2015 to 2020. We analyzed demographic data, perioperative complications, postoperative results, and radiographic results. The Japanese Orthopaedic Association (JOA) score was used to assess preoperative and postoperative spinal cord function, and the improvement rate was calculated.

RESULTS

Twenty-two patients were enrolled, including 6 patients in the anterior approach group, 11 in the posterior approach group, and 5 in the combined approach group. The operative time and intraoperative blood loss in the anterior approach group were significantly less than those in the posterior approach group and combined approach group (P = 0.00). Patients who underwent surgery within 48 hours of injury had a lower JOA score than patients who underwent surgery later (P = 0.01). Basic AS treatment before injury significantly improved JOA scores after surgery (P = 0.01).

CONCLUSIONS

All approaches can provide good clinical results, and thus, the surgical approach should be individualized. It remains unclear whether the operation should be performed as soon as possible. Basic AS treatment is an independent factor that affects the prognosis of cervical spine fracture patients with AS.

Instantaneous death risk, conditional survival and optimal surgery timing in cervical fracture patients with ankylosing spondylitis: A national multicentre retrospective study

Background

The mortality rate in patients with ankylosing spondylitis (AS) and cervical fracture is relatively high.

Objectives

This study aimed to investigate the instantaneous death risk and conditional survival (CS) in patients with AS and cervical fracture. We also studied the relationship between surgical timing and the incidence of complications.

Methods

This national multicentre retrospective study included 459 patients with AS and cervical fractures between 2003 and 2019. The hazard function was used to determine the risk of instantaneous death. The five-year CS was calculated to show the dynamic changes in prognosis.

Results

The instantaneous death risk was relatively high in the first 6 months and gradually decreased over time in patients with AS and cervical fracture. For patients who did not undergo surgery, the instantaneous risk of death was relatively high in the first 15 months and gradually decreased over time. For patients with American Spinal Injury Association impairment scale (ASIA) A and B, the 5-year CS was 55.3% at baseline, and improved steadily to 88.4% at 2 years. Odds ratios (ORs) for pneumonia, electrolyte disturbance, respiratory insufficiency, and phlebothrombosis decreased as the surgery timing increased.

Conclusion

Deaths occurred mainly in the first 6 months after injury and gradually decreased over time. Our study highlights the need for continued surveillance and care in patients with AS with cervical fractures and provides useful survival estimates for both surgeons and patients. We also observed that early surgery can significantly increase functional recovery, and decrease the incidence of complications and rehospitalisation.

Does the Level of Pedicle Subtraction Osteotomy Affect the Surgical Outcomes in Ankylosing Spondylitis-Related Thoracolumbar Kyphosis With the Same Curve Pattern?

STUDY DESIGN

A retrospective study.

OBJECTIVE

To investigate the effect of pedicle subtraction osteotomy (PSO) level on the surgical outcomes in ankylosing spondylitis-related thoracolumbar kyphosis with the same curve pattern.

METHODS

ankylosing spondylitis (AS) patients with thoracolumbar kyphosis, who underwent 1-level lumbar PSO between March 2006 and June 2017, were retrospectively reviewed. Criteria for curve-matched thoracolumbar kyphosis were: (1) have same level of preoperative apex (pre-apex); (2) have similar global kyphosis (GK, the angle between the superior/inferior endplate of the maximally tilted upper and lower end vertebra) (the difference of GK less than 15˚). The radiographic parameters measured were sagittal vertical axis (SVA, the horizontal distance between the C7 plumb line and the posterosuperior corner of the S1), GK, thoracic kyphosis (TK, the angle between the T5 superior endplate and the T12 inferior endplate), lumbar lordosis (LL, the angle between the L1 and S1 superior endplate), sacral slope (SS, the angle between the sacral endplate and the horizontal line), pelvic tilt (PT, the angle between the vertical and the line joining the midpoint of the sacral plate and hip axis), and pelvic incidence (PI, the angle between the line vertical to the superior margin of S1 and the line connecting the sacral plate midpoint with the hip joint axis). All of these parameters and health-related quality of life (HRQoL, evaluated by preoperative and the last follow-up questionnaires including ODI and VAS) scores were collected before surgery and at the last follow-up. According to their osteotomy level, patients were devided into 2 sub-groups (L1 group and L2 group), and differences of these mentioned parameters between 2 groups were compared.

RESULTS

26 curve-matched patients were recruited with a mean follow-up of 37.2 months. All patients improved significantly after surgery in HRQoL scores (VAS 1.6 vs 5.4, P < 0.001; ODI 11.9 vs 26.4, P < 0.001). Except for TK and PI, those radiographic parameters were also observed to be significantly changed after surgery. Compared to L2 group, PSO at L1 may have larger correction of TK (ΔTK -6.8 vs -0.3°, P = 0.164), PI (ΔPI -7.4 vs -0.7°, P = 0.364) and smaller correction of SVA (ΔSVA -105.3 vs -128.5 mm, P = 0.096), LL (ΔLL -31.1 vs -43.0°, P = 0.307) and SS (ΔSS 6.9 vs 12.2°, P = 0.279) but had no statistical significance.

CONCLUSION

The results of this investigation showed that in AS-related thoracolumbar kyphosis patients with the same curve pattern, the different levels of osteotomy had little effect on the improvement of surgical outcomes. However, osteotomy at L2 is more likely to obtain a larger correction of SVA compared to osteotomy at L1.

Kyphoplasty for thoracic and lumbar fractures with an intravertebral vacuum phenomenon in ankylosing spondylitis patients

Background

Intravertebral vacuum phenomenon (IVP) is a special sign after vertebral fractures, which is common in patients with ankylosing spondylitis (AS) and may indicate pseudarthrosis and bone nonunion that lead to spinal instability. The objective of this study is to evaluate the efficacy and safety of kyphoplasty (KP) in treating such types of vertebral fractures with AS.

Methods

Sixteen patients with AS suffering from thoracic or lumbar fractures with IVP received KP from 2015 to 2020 and were monitored for more than 1 year. The visual analog scale (VAS) score was used to evaluate back pain relief. The Oswestry Disability Index (ODI) questionnaire was used to assess the improvement of the patients' living quality. The anterior and middle vertebral height restoration ratio (AVH, MVH) and the kyphotic angle (KA) were used to evaluate the radiographic results.

Results

The mean follow-up period was 20.8 months (12–28 months). The VAS and ODI significantly reduced at 3 days, 3 months after surgery, and at the last follow-up compared with the preoperative outcomes (p < 0.05). The AVH and MVH were significantly increased compared with the preoperative outcomes (p < 0.05). There was a significant correction in the KA between pre- and postoperative assessments (p < 0.05). Asymptomatic intradiscal polymethylmethacrylate (PMMA) cement leakage was found in two patients.

Conclusions

For thoracic or lumbar fractures with IVP in AS patients, KP may be safe and effective, which achieves pain relief and satisfying functional improvement, restores the anterior and middle height, and corrects the kyphotic angle of the fractured vertebra.

A brief human history of ankylosing spondylitis: A scoping review of pathogenesis, diagnosis, and treatment

Background

Ankylosing spondylitis (AS) is a chronic, progressive, inflammatory disease of the spine and SI joints. Diagnostic criteria and treatments have continued to evolve, necessitating a historical compendium of AS and its management. This paper aims to review the historical context underlying the discovery of AS, as well as the major diagnostic and therapeutic discoveries in the last two centuries.

Methods

A scoping review of the literature pertaining to AS was performed via the Pubmed, Scopus, and Web of Science databases. Future directions of AS treatments were assessed by querying the clinicaltrials.gov website.

Results

The history of AS can be traced as far back as ancient Egypt (as evidenced by the discovery of its presence in ancient Egyptian mummies) to the late 20th century, when the inherited nature of AS was linked to a genetic factor, HLA-B27. Each discovery made throughout the years led to further investigations into the pathophysiology, diagnosis, and treatment of AS. The criteria to differentiate AS from rheumatoid arthritis were first reported in 1893. Since then, diagnostic criteria for AS have undergone a series of changes before the present-day diagnostic criteria for AS were ultimately determined in 2009 by the Assessment of Spondyloarthritis International Society.

Conclusion

As the pathophysiology of AS is better understood, healthcare providers are able to diagnose and treat the condition more effectively. In particular, earlier diagnosis and multiple treatment options have facilitated efficient and more effective treatment.

Research of a Safe and Simplified Intertransverse Process Approach for the Lower Thoracic Interbody Surgery

Objective

To assess a safe surgical approach for intertransverse process lower thoracic intervertebral body fusion (ITIF) based on measurements from enhanced three‐dimensional CT reconstruction, cadaver simulated operation, and patient operation.

Methods

Enhanced three‐dimensional CT image reconstruction was performed for 20 healthy volunteers on thoracic segments T8–T12. The length of the transverse process (LTP), distance between the upper and lower transverse processes (DULTP), remote distance of the transverse process (RDTP), height of the extraforaminal intervertebral space (HEIS), and oblique diameter of the intervertebral space (ODIS) were measured and recorded. The blood vessels of the intertransverse lower thoracic region were observed, and their internal diameters were measured. The rib‐intervertebral space relationship for T10/11 and T11/12 was measured in 104 patients of the thoracic skeleton. Then, based on the data from the CT measurements, simulated surgery was performed on six human cadavers at the T11/12 level. An ankylosing spondylitis (AS) patient with a fracture of the T10/11 level was eventually operated on with the ITIF technique.

Results

No significant difference was found between the lengths of the left and right thoracic transverse processes. The relationship of the values of the LTP and RDTP for the measured vertebrae were found to be as follows:T8 > T9 > T10 > T11 > T12. For HEIS and DULTP, T8–9 < T9–10 < T10–11 < T11–12. The results for the ODIS were as follows: T8–T9 < T9–T10 < T10–T11 < T11–T12. The blood vessel inner diameter of T11–12 was less than that of T10–11, while there was no significant difference between the diameters for T8–9 and T11–12. Almost half of the volunteer's T10/11 intervertebral spaces were covered posteriorly by the 11th rib (45.19% on left and 41.35% on right), while for most patients, the T11/12 intervertebral space was not covered by the 12th rib (98.08%). According to the cadaver experiments, intervertebral bone grafting and ipsilateral pedicle screw fixation were performed to simulate the operation. One patient with a combined AS and T10/11 fracture was then operated on with the ITIF technique and followed up for 3 years with satisfactory results.

Conclusion

As verified by 3D CT reconstruction measurements, cadaver simulation surgery and patient operation with follow‐up, the intertransverse process approach for some T10/T11 and almost all T11/T12 segments is a safe surgical pathway for operations such as ITIF, fracture bone grafting, clearance of focal lesions.

Spinal cord injury and spinal fracture in patients with ankylosing spondylitis

Background

Spinal cord injury (SCI) and spinal fracture are major complications in patients with ankylosing spondylitis (AS) who sustain spinal trauma. The purpose of this study was to investigate the incidence, predictors, and sequelae of spinal trauma in patients with AS.

Methods

This retrospective study included patients with AS who were admitted for spinal trauma between January 1, 2006, and June 30, 2016. The study compared clinical outcomes of patients between group 1: SCI alone, group 2: spinal fracture alone (no SCI), and group 3: both SCI and spinal fracture.

Results

Of the 6285 patients with AS admitted during the retrospective study period, only 105 suffered from spinal trauma and were enrolled in the study. Case number in group 1, 2, and 3 was 11(10.48%), 45(42.85%), and 49(46.67%), respectively. Among the patients with spinal fractures, 52.1% had SCI. Bamboo spine was significantly more prevalent in the fracture group than in the nonfracture group (78.7% vs. 36.4%; P = 0.006). Patients with SCI had more instances of subluxation or dislocation (48.3% vs. 8.9%; P < 0.001) and more cases of spinal epidural hematoma (SEH; 21.7% vs. 2.2%; P = 0.003) than patients without SCI. The rate of delayed diagnosis for spinal fracture was 31.4%, with one-third of patients developing delayed SCI. Among the patients with incomplete SCI, 58.3% achieved neurological improvement after treatment (P = 0.004).

Conclusions

Patients with AS and bamboo spine at radiograph had a higher rate of spinal fracture, which may be an important factor in SCI in patients with AS. Spinal fractures involving the C3–C7 region, subluxation or dislocation, severe spinal fracture, and SEH were found to be predictive of SCI, and SCI in patients with AS resulted in higher mortality and complication rates.

Classification and Treatment for Cervical Spine Fracture with Ankylosing Spondylitis: A Clinical Nomogram Prediction Study

Objective

Through the follow-up analysis of cervical spine fracture cases with ankylosing spondylitis (AS), a treatment-oriented fracture classification method is introduced to evaluate the clinical efficacy guided by this classification method.

Method

A retrospective analysis was performed on 128 AS patients who underwent comprehensive treatment in the Spine Surgery Department of Qingdao University Hospital from January 2009 to May 2018. Statistics of patient demographic data, distribution of different fractures corresponding to surgical methods, 3-year follow-up outcomes, and summary of objective fracture classification methods were analyzed. A prospective 5-year follow-up study of 90 patients with AS cervical spine fractures from June 2015 to August 2020 was also included. Statistical differences on the distribution of factors such as case information, cervical spine sagittal sequence parameters, and fracture classification were assessed. Correlations between surgical information, American Spinal Injuries Association grade (ASIA), modified Japanese Orthopaedic Association scores (mJOA), and other factors were analyzed to establish a nomogram predictive model for curative effect outcomes. Overall, three major types and the four subtypes of AS cervical spine fractures were evaluated based on the clinical efficacy of the classification and the selection of surgical treatment methods.

Result

The most common type of fracture was type II (30 cases, 33.33%), most of the subtypes were A (37 cases), followed by B (36 cases) and C (17 cases). Twenty-four of 28 patients with type I underwent anterior surgery, and 47 of 62 patients with type II and III underwent posterior surgery. The average follow-up time was 25.76 ± 11.80 months. The results of predicting clinical variables are different but include factors such as fracture type and subtype, type of operation, and age. The predictor variables include the above-mentioned similar variables, but survival is more affected by the fracture type of the patient.

Conclusion

This predictive model based on follow-up information delineation points out the impact of ankylosing spondylitis cervical spine fracture classification on surgical selection and clinical efficacy.

Drug Discovery in Spinal Cord Injury With Ankylosing Spondylitis Identified by Text Mining and Biomedical Databases

Spinal cord injury (SCI) and ankylosing spondylitis (AS) are common inflammatory diseases in spine surgery. However, it is a project where the relationship between the two diseases is ambiguous and the efficiency of drug discovery is limited. Therefore, the study aimed to investigate new drug therapies for SCI and AS. First, text mining was used to obtain the interacting genes related to SCI and AS, and then, the functional analysis was conducted. Protein–protein interaction (PPI) networks were constructed by STRING online and Cytoscape software to identify hub genes. Last, hub genes and potential drugs were performed after undergoing drug–gene interaction analysis, and MicroRNA and transcription factors regulatory networks were also analyzed. Two hundred five genes common to “SCI” and “AS” identified by text mining were enriched in inflammatory responses. PPI network analysis showed that 30 genes constructed two significant modules. Ultimately, nine (SST, VWF, IL1B, IL6, CXCR4, VEGFA, SERPINE1, FN1, and PROS1) out of 30 genes could be targetable by a total of 13 drugs. In conclusion, the novel core genes contribute to a novel insight for latent functional mechanisms and present potential prognostic indicators and therapeutic targets in SCI and AS.

Spinal Fractures in Ankylosing Spondylitis: Patterns, Management, and Complications in the United States - Analysis of Latest Nationwide Inpatient Sample Data

Objective

Ankylosing spondylitis (AS) is a rheumatic inflammatory disease marked by chronic inflammation of the axial skeleton. This condition, particularly when severe, can lead to increased risk of vertebral fractures attributed to decreased ability of the stiffened spinal column to sustain normal loads. However, little focus has been placed on understanding the locations of spinal fractures and associated complications and assessing the correlation between these. In this review, we aim to summarize the complications and treatment patterns in the United States in AS patients with spinal fractures, using the latest Nationwide Inpatient Sample (NIS) database (2016–2018).

Methods

We analyzed the NIS data of years 2016–2018 to compare the fracture patterns and complications.

Results

A total of 5,385 patients were included. The mean age was 71.63 years (standard deviation [SD], 13.21), with male predominance (83.8%). The most common population is Whites (77.4%), followed by Hispanics (7.9%). The most common fracture level was thoracic level (58.3%), followed by cervical level (38%). Multiple fracture levels were found in 13.3% of the patients. Spinal cord injury (SCI) was associated with 15.8% of the patients. The cervical level had a higher proportion of SCI (26.5%), followed by thoracic level (9.2%). The mean Elixhauser comorbidity score was 4.82 (SD, 2.17). A total of 2,365 patients (43.9%) underwent surgical treatment for the fractures. The overall complication rate was 40.8%. Respiratory complications, including pneumonia and respiratory insufficiency, were the predominant complications in the overall cohort. Based on the regression analysis, there was no significant difference (p=0.45) in the complication rates based on the levels. The presence of SCI increased the odds of having a complication by 2.164 times (95% confidence interval, 1.722–2.72; p≤0.001), and an increase in Elixhauser comorbidity score predicted the complication and in-hospital mortality rate (p≤0.001).

Conclusion

AS patients with spinal fractures have higher postoperative complications than the general population. The most common fracture location was thoracic in our study, although it differs with few studies, with SCI occurring in 1/6th of the patients.

Decreasing pressure injuries and acute care length of stay in patients with acute traumatic spinal cord injury

OBJECTIVES

Identifying factors associated with the occurrence of pressure injuries (PI) during acute care and with longer length of stay (LOS), focusing on modifiable factors that can be addressed and optimized by the acute rehabilitation team.

DESIGN

Prospective cohort study.

SETTING

A single Level-1 trauma center specialized in SCI care.

PARTICIPANTS

A cohort of 301 patients with acute TSCI was studied.

OUTCOME MEASURES

The primary outcome was the occurrence of PI during acute care stay. The secondary outcome was acute care LOS. Bivariate and multivariate logistic or linear regression analyses were performed to determine the association between non-modifiable factors and outcomes (PI of any stage and acute LOS), whereas bivariate and hierarchical multivariate logistic or linear regression analyses were used for modifiable factors.

RESULTS

When controlling for the level and severity of the TSCI, the occurrence of pneumonia (OR = 2.1, CI = 1.1-4.1) was significantly associated with the occurrence of PI. When controlling for the level and severity of the TSCI, the occurrence of medical complications (PI, urinary tract infection and pneumonia) and lesser daily therapy resulted in significantly longer acute care LOS (P < .001).

CONCLUSIONS

Prevention of PI occurrence and the optimization of the acute care LOS represent crucial challenges of the acute rehabilitation team, as they are significantly associated with higher functional outcomes. Patients who develop pneumonia may benefit from more aggressive prevention strategies to reduce PI occurrence. Systematic protocols for the prevention of complications as well as greater volume of therapy interventions should be considered to optimize the acute care LOS.

Epidural hematoma in patients with ankylosing spondylitis requiring surgical stabilization: a single-institution retrospective review with literature analysis

OBJECTIVE

Ankylosing spondylitis (AS) is a chronic inflammatory disease affecting the sacroiliac joints and axial spine that is closely linked with human leukocyte antigen-B27. There appears to be an increased frequency of associated epidural hematomas in spine fractures in patients with AS. The objective was to review the incidence within the literature and a single-institution experience of the occurrence of epidural hematoma in the context of patients with AS requiring spine surgery.

METHODS

Deep 6 AI software was used to search the entire database of patients at a single level I trauma center (since the advent of the institution's modern electronic health record system) to look at all patients with AS who underwent spinal surgery and who had a diagnosis of epidural hematoma. Additionally, a systemic literature review was performed of all papers evaluating the incidence of epidural hematoma in patients with spine fractures.

RESULTS

A single-institution, retrospective review of records from 2009 to 2020 yielded a total of 164 patients with AS who underwent spine surgery. Of those patients, 17 (10.4%) had epidural hematomas on imaging, with the majority requiring surgical decompression. These spine fractures occurred close to the cervicothoracic or thoracolumbar junction. The patients ranged in age from 51 to 88 years, and there were 14 males and 3 females in the cohort. Eight patients were administered an antiplatelet and/or anticoagulant agent, and the rest were not. All patients required surgical stabilization, with 64.7% of patients also requiring decompressive laminectomies for evacuation of the hematoma and spinal cord decompression. Only 1 death was reported in the series. There was a tendency toward neurological improvement after surgical intervention.

CONCLUSIONS

AS has been a well-described pathologic process that leads to an increased risk of three-column injury in spine fracture, with an increased incidence of symptomatic epidural hematoma compared with patients without AS. Early recognition of this entity is important to ensure that appropriate surgical management includes addressing compression of the neural elements in addition to surgical stabilization.

The role of an anterior approach in the treatment of ankylosing spondylitis-associated cervical fractures: a systematic review and meta-analysis

OBJECTIVE

Cervical fractures in patients with ankylosing spondylitis can have devastating neurological consequences. Currently, several surgical approaches are commonly used to treat these fractures: anterior, posterior, and anterior-posterior. The relative rarity of these fractures has limited the ability of surgeons to objectively determine the merits of each. The authors present an updated systematic review and meta-analysis investigating the utility of anterior surgical approaches relative to posterior and anterior-posterior approaches.

METHODS

After a comprehensive literature search of the PubMed, Cochrane, and Embase databases, 7 clinical studies were included in the final qualitative and 6 in the final quantitative analyses. Of these studies, 6 compared anterior approaches with anterior-posterior and posterior approaches, while 1 investigated only an anterior approach. Odds ratios and 95% confidence intervals were calculated where appropriate.

RESULTS

A meta-analysis of postoperative neurological improvement revealed no statistically significant differences in gross rates of neurological improvement between anterior and posterior approaches (OR 0.40, 95% CI 0.10-1.59; p = 0.19). However, when analyzing the mean change in neurological function, patients who underwent anterior approaches had a significantly lower mean change in postoperative neurological function relative to patients who underwent posterior approaches (mean difference [MD] -0.60, 95% CI -0.76 to -0.45; p < 0.00001). An identical trend was seen between anterior and anterior-posterior approaches; there were no statistically significant differences in gross rates of neurological improvement (OR 3.05, 95% CI 0.84-11.15; p = 0.09). However, patients who underwent anterior approaches experienced a lower mean change in neurological function relative to anterior-posterior approaches (MD -0.46, 95% CI -0.60 to -0.32; p < 0.00001). There were no significant differences in complication rates between anterior approaches, posterior approaches, or anterior-posterior approaches, although complication rates trended lower in patients who underwent anterior approaches.

CONCLUSIONS

The results of this review and meta-analysis demonstrated the varying benefits of anterior approaches relative to posterior and anterior-posterior approaches in treatment of cervical fractures associated with ankylosing spondylitis. While reports demonstrated lower degrees of neurological improvement in anterior approaches, they may benefit patients with less-severe injuries if lower complication rates are desired.

'Can you touch your toes?' spondyloarthropathies and acute anterior uveitis for primary eyecare practitioners

The rheumatological diseases known as spondyloarthropathies (SpAs) are reviewed with respect to the current classifications of SpAs and from the perspective of ophthalmic practitioners. The focus is on the most common spondyloarthropathy, ankylosing spondylitis (AS), and the key symptoms, such as inflammatory back pain. The association with HLA-B27 and acute anterior uveitis (AAU) and the major clinical considerations for primary eye care practitioners are reviewed. An atypical case study illustrates difficulties in the detection and diagnosis of ankylosing spondylitis.

Trends in hospitalizations for vertebral compression fracture in ankylosing spondylitis: data from the National Inpatient Sample 2000-2014

Ankylosing spondylitis (AS) patients are at increased risk of vertebral compression fractures (VCF). Our objective was to examine the yearly trend of VCF hospitalizations in AS patients as compared to rheumatoid arthritis (RA) and the general population. National Inpatient Sample (NIS) database (2000-2014) was used to identify adult (≥ 18 years) hospitalizations, based on validated ICD-9 diagnosis codes. The rate of VCF hospitalizations, as a primary diagnosis, was assessed in three mutually exclusive groups: AS, RA, and the general population. The prevalence of VCF hospitalization was highest in AS (2.70%), compared to 0.77% in RA and 0.35% in the general population. Over the 15-year period, VCF hospitalization in AS was noted to have an increasing trend (Annual Percent Change (APC) = 4.73, p < 0.05) in contrast to the stable trend in the general population (APC = 0.34, p = NS) and a declining trend in RA (APC -3.61, p < 0.05). VCF related to AS was also associated with a longer hospital stay as compared to the general population (8.1 days vs. 5.1 days, p < 0.05) and higher inpatient mortality (3.4% vs. 1.0%, p < 0.05). A higher rate of VCF hospitalization along with an increasing trend was noted in AS as compared to RA and compared to the general population. Better screening approaches and treatment strategies for AS patients with VCF risk are urgently needed to reduce hospitalizations and related complications. Key Points • An increasing trend of VCF hospitalization was noted in AS, in contrast to a declining trend in RA and a stable trend in the general population. • VCF in AS was associated with longer hospital stay and higher inpatient mortality than in RA and the general population.

Spinal trauma in DISH and AS: is MRI essential following the detection of vertebral fractures on CT?

BACKGROUND

Both ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) cause a rigid spine, but through different pathophysiology. Recent data has shown that characteristic fracture patterns may also differ following trauma since the posterior osseous and soft tissue elements are often spared in DISH. CT and MRI are important in diagnosing spine injury, but given the differences between AS and DISH, the utility of obtaining both studies in all patients warrants scrutiny.

PURPOSE

To assess the prevalence of posterior element injury on CT and MRI in DISH and AS patients with known vertebral body injury detected on CT; to determine whether MRI demonstrates additional injuries in neurologically intact patients presumed to have isolated vertebral body injuries on CT.

STUDY DESIGN

Multicenter, retrospective, case-control study.

PATIENT SAMPLE

DISH and AS patients presenting after spine trauma between 2007 and 2017.

OUTCOME MEASURES

Review of CT and MRI findings at the time of presentation.

METHODS

One hundred sixty DISH and 85 AS patients presenting after spine trauma were identified from 2 affiliated academic hospitals serving as level 1 trauma and tertiary referral centers. A diagnosis of DISH or AS was verified by a board-certified emergency radiologist with 3 years of experience. Age, gender, mechanism of injury, fracture type, spine CT and MRI imaging findings, surgical intervention, and neurologic deficit were recorded. The CT and MRI studies were reviewed by the same radiologist for fracture location and type using the AO spine classification. No funding source or conflict of interest was present.

RESULTS

Median age was 72 and 79 years old for the AS and DISH groups, respectively. Both were predominantly male (81%) and most presented after a low energy mechanism of injury (74% and 73%). Type C AO spine injuries were seen in 52% of AS patients but only 4% of DISH patients. In patients with known vertebral body injury on CT, additional injury to the posterior elements on CT or MRI in DISH patients was 51% versus 92% in AS patients. However, in patients with an isolated vertebral body fracture on CT and no neurological deficit, MRI identified posterior element injury in only 4/22 (18%) DISH patients compared to 5 of 7 (71%) AS patients. None of the MRI findings in the DISH patients were considered clinically important while all 5 AS patients eventually underwent operative treatment despite having no neurological deficit. Epidural hematoma on MRI was seen in 43% of AS patients as opposed to 5% of DISH patients.

CONCLUSION

Based on our small sample size, CT alone may be adequate in DISH patients with isolated vertebral body fractures and no neurologic deficit, but an additional MRI should be considered in the presence of an unclear neurological exam or deficit. MRI should be strongly considered for any AS patient regardless of neurologic status.

Post-traumatic spinal hematoma in ankylosing spondylitis

PURPOSE

The purpose of this study is to examine the incidence, location, and magnetic resonance imaging (MRI) features of spinal epidural hematoma (SEH) and spinal subdural hematoma (SSH) in post-traumatic ankylosing spondylitis (AS) patients.

METHODS

A total of 2256 consecutive referrals for urgent and emergency MRI scans of the spine over a period of eight years and nine months were manually reviewed for any mentions indicating axial ankylosis and post-traumatic spinal hematoma. We found 164 patients with ankylosed spines complicated by spinal fracture, of whom 32 had AS. Of the 132 excluded patients, 80 had diffuse idiopathic skeletal hyperostosis (DISH). The primary outcome was the presence of spinal hematoma, and the secondary outcome was spinal canal narrowing and spinal cord impingement. Two musculoskeletal radiologists and one fellow in musculoskeletal radiology reviewed the images for the presence of spinal hematoma and related signal characteristics, blinded to one another and initial reports.

RESULTS

Of 28 post-traumatic AS patients, 19 had SEHs and five had spinal SSHs. There was a statistically significant difference between Frankel grades before and after surgery in respect of neurological improvement (p = 0.008). Patients who had radiologically proven spinal cord impingement showed more severe neurological deficits (p = 0.012). Hematomas with T1 heterogeneity showed a significantly increased delay (p = 0.047) between injury and imaging, while other signal characteristics were only approximate.

CONCLUSIONS

Both SEH and SSH are common complications in post-traumatic AS patients. Patients benefit from surgery, but the relevance of spinal hematoma as a separate factor causing neurological deficit remains unclear.

Neurologically Asymptomatic Lumbar Traumatic Dislocation With Vascular Compression in a Patient With Ankylosing Spondylitis: Case Report

BACKGROUND

Ankylosing spondylitis (AS) is associated with high rates of severe thoracolumbar fractures, in many cases with neurological deficits. It is currently a point of debate as to whether the optimal surgical treatment is posterior fixation and fusion or combined approaches. Vascular injuries in this kind of fracture are a challenging issue to solve in the management of these patients.

METHODS

We are reporting the case of a 65-year-old man who presented an L4 traumatic fracture-dislocation. He had a long history of symptomatic AS. No neurological deficits were detected during the initial exploration. During the preoperative work-up, a lumbar spine computed tomography (CT) scan was taken with vascular reconstruction of the abdominal vessels. It confirmed the compression of the abdominal aorta, which had caused more than 90% stenosis. A posterior approach, an open reduction, and fixation with pedicle screws were performed, without hemodynamic or neurological changes. A postoperative angiography demonstrated a complete recovery of the vessel caliber, without contrast leaks.

RESULTS

After a 2-year follow-up, the patient was pain free and the CT scan revealed bone fusion.

CONCLUSIONS

The vascular structures involved in severe thoracolumbar fractures present a dangerous situation that should be considered in the choice of the surgical approach. The posterior approach alone may be a good option in the absence of vascular damage. However, due to risk of vessel rupture during the fracture reduction, vascular surgeons must take part in the surgery.

LEVEL OF EVIDENCE

5.

CLINICAL RELEVANCE

The article provides help for surgeons who have to treat severe fractures in the context of ankylosing spondylitis.

Spinal fractures in patients with ankylosing spondylitis: A case report and literature review

Background

Severe ankylosing spondylitis (AS) affects the entire spine, increasing the risk of vertebral fractures. There are several fusion procedures used (e.g., anterior, posterior, or combined 360° procedures) to stabilize these fractures.

Case Description

A 45-year-old male with a 33-year diagnosis of AS presented with a progressive quadriparesis of 6 months' duration. Previously, he had surgery on both hips. The medical report documented degenerative spondylolisthesis at the C5-C6 level along with syndesmophytes a herniated disc and stenosis. Following a circumferential decompression/fusion without complications, the patient's symptoms resolved.

Conclusion

For patients presenting with cervical fractures and AS, circumferential surgical decompression/ fusion may result in good outcomes.

Improvement of Sleep Quality in Patients With Ankylosing Spondylitis Kyphosis After Corrective Surgery

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim of this study is to investigate the changes in sleep quality in patients surgically treated for kyphosis due to ankylosing spondylitis (AS) and the correlation between these changes and spinal sagittal realignment.

SUMMARY OF BACKGROUND DATA

Sleep problems are prevalent in AS patients. However, little attention has been paid to the sleep quality in patients with AS kyphosis and the effect of surgical intervention on sleep quality.

METHODS

We have retrospectively reviewed 62 patients with AS-induced thoracolumbar kyphosis who underwent surgically treatment from October 2012 to November 2016. Sleep quality was evaluated by the Pittsburgh Sleep Quality Index (PSQI) questionnaire. Preoperative and postoperative radiological characteristics and supine function were documented. We compared the above-mentioned parameters pre- and 24 months postoperatively and analyzed the correlation of the changes in the PSQI with the changes in radiological characteristics.

RESULTS

Fifity-one patients (82%) classified as poor sleepers preoperatively. In addition to use of sleeping medication, each domain of the PSQI and the total PSQI were increased postoperatively. Improved sleep quality was correlated with changes in spinal sagittal characteristics, among which the lumbar lordosis (LL) and the chin-brow vertical angle (CBVA) were the independent correlation factors. The number of patients with supine dysfunction decreased from 89% to 15% after surgery. Significant differences were identified in the PSQI scores between the patients with and without supine dysfunction either pre- or postoperatively.

CONCLUSION

Surgical correction of spinal deformity may improve sleep quality and supine function in patients with AS. Spinal sagittal realignment may be correlated with the improvement of sleep quality.

LEVEL OF EVIDENCE

4.

Spontaneous intraoperative lumbar fracture leading to an unexpected correction in ankylosing spondylitis corrective surgery - a case report

Severe kyphotic deformity in patients with ankylosing spondylitis can be corrected surgically to achieve a better spinal alignment and an improved visual axis. Different surgical techniques are used today depending on the extent of ossification and the degree of kyphosis. It is well known that the underlying disease leads to distinct biomechanical changes of the spinal column causing an increased fracture risk especially in case of minor trauma. This includes manipulations during surgical procedures as well as during the required perioperative measures.

We present the case of a 45-year-old patient with severe global kyphotic deformity due to ankylosing spondylitis. During the elective corrective surgery (pedicle subtraction osteotomy at the level of L3) the patient sustained a spontaneous fracture at L2/3. This fortunately nondisplaced wedge-shaped fracture in the sense of a Smith-Peterson osteotomy led to a spontaneous correction of the kyphosis. The described unexpected event required a change in the surgical strategy. Correction could be achieved using a two-stage surgical procedure without further drawbacks for the patient.

This case report stresses the need of particular attention regarding the increased susceptibility of the spinal column in case of ankylosing spondylitis.

Management of cervical fractures in ankylosing spondylitis patients: immediate fixation effort via vertebroplasty with one-staged combined anterior and posterior fixation

The ankylosed spine is prone to fracture even as a result of minor trauma due to its changed biomechanical properties. Fractures in ankylosing spondylitis (AS) patients are highly unstable and surgical intervention for fixation is warranted. Implant failure rates are high and combined anterior and posterior fixation is required to enhance the fixation outcome. For fusion, anterior interbody fusion or posterior bone graft fusion is often adopted. Here, we introduce a new method which combines vertebroplasty with anterior and posterior approaches to improve pain control, facilitate the long-term fixation outcome and mechanics, and decrease perioperative risks with prompt stabilization, especially in patients with spine curve deformity. Here, we present two AS cases with cervical spine fracture treated with this new method.

Diffuse idiopathic skeletal hyperostosis: Etiology and clinical relevance

Diffuse idiopathic skeletal hyperostosis (DISH) is a systemic bone-forming condition characterized by the presence of at least three bony bridges at the anterolateral spine. The aim of this review was to address the present state of pathophysiological knowledge, the clinical relevance, and diagnosis of DISH. The pathogenesis of DISH is currently unknown. The presence of DISH has been associated with older age, male sex, obesity, hypertension, atherosclerosis, and diabetes mellitus. Because the new bone forms mainly at entheseal sites, local fibroblasts, chondrocytes, collagen fibers, and calcified matrix are probably influenced by genetic, vascular, metabolic, and mechanical factors. Diagnosing the presence of DISH is of clinical importance, because the risk of a spinal fracture increases and associations with the metabolic syndrome, coronary and aortic disease, and respiratory effects are strong. Unravelling the pathogenesis of DISH can impact the field of regenerative medicine and bone tissue regeneration.

Advances in nanomedicine for the treatment of ankylosing spondylitis

Ankylosing spondylitis (AS) is a complex disease characterized by inflammation and ankylosis primarily at the cartilage–bone interface. The disease is more common in young males and risk factors include both genetic and environmental. While the pathogenesis of AS is not completely understood, it is thought to be an immune-mediated disease involving inflammatory cellular infiltrates, and human leukocyte antigen-B27. Currently, there is no specific diagnostic technique available for this disease; therefore conventional diagnostic approaches such as clinical symptoms, laboratory tests and imaging techniques are used. There are various review papers that have been published on conventional treatment approaches, and in this review work, we focus on the more promising nanomedicine-based treatment modalities to move this field forward.

Is routine MRI of the spine necessary in trauma patients with ankylosing spinal disorders or is a CT scan sufficient?

BACKGROUND

Ankylosing spinal disorder (ASD) patients are at a greater risk for spinal fractures due to osteoporosis and rigidity of the spinal column. These fractures are associated with a high risk of neurologic compromise resulting from delayed or missed diagnoses. Although computed tomography (CT) is usually the initial imaging modality, magnetic resonance imaging (MRI) has been proposed as mandatory to help identify spinal injuries in ASD patients with unexplained neck or back pain or known injuries to help identify noncontiguous fractures. However, some studies have also shown that neurological injury can result from the required patient transfer and positioning for an MRI.

PURPOSE

The purpose of our study was to assess the frequency with which an MRI identified an injury not previously identified with CT, and whether this affected the treatment and outcome of the patient. Secondarily, we attempted to identify clinical or CT findings that may render an MRI particularly useful.

STUDY DESIGN

Retrospective review.

PATIENT SAMPLE

Patients with ASD who sustained acute spine fractures from 2005 to 2015.

OUTCOME MEASURES

Acute fractures identified by CT scan and MRI upon admission; neurologic status upon admission and discharge, mode of injury, type of fracture, and final intervention before and after MRI assessment.

METHODS

A total of 124 patients with a diagnosis of diffuse idiopathic skeletal hyperostosis (DISH) or ankylosing spondylitis (AS) were identified by searching the radiology database of a level I trauma center with diagnosis keywords. Final radiology reports were assessed to determine presence and type of fracture(s) from CT. MRI report was then reviewed to assess if additional fractures or injuries were identified beyond that already known from the CT. Neurologic status upon admission and discharge, mode of injury, type of fracture, and final intervention were determined by inpatient notes and/or operative reports. No source funding or conflict of interest was present pertaining to this study.

RESULTS

In the designated time frame, 124 ASD patients with injuries of the spine were identified who had obtained both a baseline CT and MRI. Six patients (4.8%) had additional injuries on MRI that had not been identified with CT. Four of these six patients had a change in treatment plan (three operative and one nonoperative) based on subsequent MRI findings. These included a (1) C4-5 hyperextension injury, (2) C6-7 hyperextension injury, (3) C7 bony fracture with C5-T4 epidural hematoma, and (4) C5-C6 hyperextension injury treated in a brace. Two of the six patients that had additional injuries identified on MRI had no change in their treatment plan. One patient had an additional lumbar extension injury identified above a previously diagnosed injury on CT, which was managed with a Thoracolumbosacral Orthosis (TLSO) according to the original plan. One patient died who had a known odontoid fracture and a suspected C6-7 hyperextension injury, and was identified on MRI as also having a C3-C4 hyperextension injury and a C2 spinal cord transection.

CONCLUSIONS

In this study, 3.2% (4/124) of patients with ASD who presented to a level I trauma center with an acute spine injury identified with CT required a change in their treatment plan based on subsequent MRI findings. Only one fracture was missed on CT imaging, with the other missed injuries all being either disco-ligamentous hyperextension injuries through mobile discs or intracanal pathology. Our recommendation is that the routine use of MRI be limited to patients with nonankylosed levels in which a disco-ligamentous injury may have occurred, and in patients with neurological deficits that require investigation of the spinal canal to assess for causes of neurological injury.

The surgical treatment strategies for thoracolumbar spine fractures with ankylosing spondylitis: a case report

Background

Ankylosing spondylitis (AS) is a chronic inflammatory disease that primarily affects spine and paraspinal soft tissue. Ankylosing spondylitis is one of the causes of osteoporosis and patients with ankylosing spondylitis tend to have spinal fractures due to limited mobility and osteoporosis. In recent years, due to the increase in the number of patients with AS, patients with AS and thoracolumbar spine fractures have gradually increased. In the past 1 year, we have treated 3 cases of AS with thoracolumbar spine fractures via simple posterior internal fixation and this paper aims to report its clinic effect.

Case presentation

All the three patients selected had a history of ankylosing spondylitis for nearly 30 years, and one of them developed a thoracolumbar spine fracture after falling when he walked, and the other two developed a thoracolumbar spine fracture without any reason. They were hospitalized for “low back pain” and were diagnosed as fractures after careful physical examination and imaging examinations such as X-ray, CT, and MRI. After the preoperative preparation was completed, all the three patients underwent surgery with simple posterior internal fixation-reduction of the fracture and pedicle screw fixation via posterior approach. All the implants-pedicle screws and connecting rods-are made of titanium alloy. For postoperative management, we asked all the patients to stay in bed for 3 weeks after the operation, and then slowly move down with the help of crutches. Fracture healing and neurological function recovery were observed postoperatively. All the three patients recovered satisfactorily after surgery, and the follow-up confirmed that the fracture healed successfully after 3 months.

Conclusions

The 3 patients included 2 men and 1 women. All the 3 patients recovered well after surgery, and the follow-up confirmed that the fracture healed successfully after 3 months. One man developed urination dysfunction after operation and recovered to normal 3 months after rehabilitation exercise.

Injuries to the Rigid Spine: What the Spine Surgeon Wants to Know

The biomechanical stability of the spine is altered in patients with a rigid spine, rendering it vulnerable to fracture even from relatively minor impact. The rigid spine entities are ankylosing spondylitis (AS), diffuse idiopathic skeletal hyperostosis, degenerative spondylosis, and a surgically fused spine. The most common mechanism of injury resulting in fracture is hyperextension, which often leads to unstable injury in patients with a rigid spine per the recent AOSpine classification system. Due to the increased risk of spinal fractures in this population, performing a spine CT is the first step when a patient with a rigid spine presents with new back pain or suspected spinal trauma. In addition, there should be a low threshold for performing a non-contrast-enhanced spine MRI in patients with a rigid spine, especially those with AS who may have an occult fracture, epidural hematoma, or spinal cord injury. Unfortunately, owing to insufficient imaging and an unfamiliarity with fracture patterns in the setting of a rigid spine, fracture diagnosis is often delayed, leading to significant morbidity and even death. The radiologist's role is to recognize the imaging features of a rigid spine, identify any fractures at CT and MRI, and fully characterize the extent of injury. Reasons for surgical intervention include neurologic deficit or concern for deterioration, an unstable fracture, or the presence of an epidural hematoma. By understanding the imaging features of various rigid spine conditions and vigilantly examining images for occult fractures, the radiologist can avoid a missed or delayed diagnosis of an injured rigid spine. ^©RSNA, 2019.

Spine surgery in patients with ankylosing spondylitis

INTRODUCTION

Ankylosing spondylitis (AS) is an idiopathic seronegative spondyloartropathy that involves mainly the axial skeleton and the sacroiliac joints. AS promotes biomechanical changes in the spine that predispose to fractures, spinal deformity and spondylodiscitis. The aim of this article is to report the clinical and laboratorial characteristics of patients with AS who underwent spinal surgery at our Institution.

METHODS

Retrospective review of medical charts of patients who had AS and underwent spinal interventions.

RESULTS

Nine patients were found and eight were included in the present study. There were three men and six women and the patients' mean age was 57 years old. All patients had pain at the involved spinal level and one patient had tetraparesis due to cervical myelopathy. Acute-phase proteins were positive in six patients (75%), and HLA-B27 was found in two patients (25%). Four patients had the radiological diagnosis of spondylodiscitis (50%) and underwent a spinal disc biopsy. They were all characterized as having aseptic spondylodiscitis. Three patients were free of pain with analgesics in their last follow-up and one patient had only partial solution of his pain. Three additional patients had spinal fractures surgically treated (37.5%) and one patient was operated because of a cervical kyphotic deformity (12.5%). There were no deaths or surgical complications in this series.

CONCLUSIONS

the majority of our clinical and laboratories findings were discrepant with the medical literature. These differences may be secondary to regional characteristics or by the fact that our population included only those patients who underwent spinal surgery.

Spine Fractures in Ankylosing Diseases: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU)

STUDY DESIGN

Review of literature and case series.

OBJECTIVES

Update and review of current treatment concepts for spine fractures in patients with ankylosing spinal disorders.

METHODS

Case presentation and description of a diagnostic and therapeutic algorithm for unstable spinal injuries with an underlying ankylosing spinal disorder (ASD) of the cervical and thoracolumbar spine.

RESULTS

Nondisplaced fractures can be missed easily using conventional X-rays. Thus, computed tomography (CT) scans are recommended for all trauma patients with ASD. In doubt or presence of any neurologic involvement additional magnetic resonance imaging (MRI) scans should be obtained. Spine precautions should be maintained all times and until definitive treatment (<24 h). Nonoperative fracture treatment is not recommended given the mechanical instability of the most commonly seen fracture patterns (AOSpine B- and C-type, M2) in patients with ASD and inherent high risk of secondary neurologic deterioration. For patients with ankylosing spondylitis (AS) or diffuse idiopathic hyperostosis (DISH) sustaining cervical spine fractures, a combined anterior-posterior instrumentation for fracture fixation is recommended. Closed reduction and patient positioning can be challenging in presence of preexisting kyphotic deformities. In the thoracolumbar (TL) spine, a posterior instrumentation extending 2 to 3 levels above and below the fracture level is recommended to maintain adequate reduction and stability until fracture healing. Minimally invasive percutaneous pedicle screws and cement augmentation can help to minimize the surgical trauma and strengthen the construct stability in patients with diminished minor bone quality (osteopenia, osteoporosis).

CONCLUSIONS

Current concepts, treatment options, and recommendations of the German Orthopedic Trauma Society-Spine Section for spinal fractures in the ankylosed spine have been outlined.

Evaluation of the comorbidity burden in patients with ankylosing spondylitis using a large US administrative claims data set

Comorbidities among US patients with ankylosing spondylitis (AS) are inadequately understood. This study compared the prevalence and incidence of comorbidities between patients with AS and matched controls using national claims databases. Adults enrolled in the MarketScan Commercial and Medicare databases with ≥ 1 inpatient or ≥ 2 non-rule-out outpatient diagnoses of AS between January 1, 2012 and December 31, 2014 were included. Patients had to have ≥ 1 AS diagnosis in 2013; the first AS diagnosis in 2013 was assigned as the index date. Control patients without AS were matched to AS patients on age, geographic region, index calendar year, and sex. Comorbidities were evaluated in AS patients and matched controls during the baseline and follow-up periods (before and after the index date, respectively). Hazard ratios of developing new comorbidities were estimated using Cox proportional hazard models adjusted for patients’ characteristics. A total of 6679 patients with AS were matched to 19,951 control patients. In addition to extra-articular manifestations of AS (inflammatory bowel disease [IBD], psoriasis, uveitis), a higher proportion of AS patients had asthma, cardiovascular disease, depression, dyslipidemia, gastrointestinal ulcers, malignancies, multiple sclerosis, osteoporosis, sleep apnea, and spinal fractures during the baseline period than matched controls. After AS diagnosis, a higher proportion of patients developed newly diagnosed cases of cardiovascular diseases, depression, osteoporosis, spinal fracture, IBD, psoriasis, and uveitis than matched controls. In this real-world, US claims-based study, patients with AS were shown to have significantly more comorbidities than matched controls.

The association between ankylosing spondylitis and the risk of any, hip, or vertebral fracture: A meta-analysis

BACKGROUND

Ankylosing spondylitis (AS) is an inflammatory rheumatic disease and strongly associated with an increased risk of fractures. A great proportion of patients with AS are suffering from sustaining fractures and the aim of this study is to evaluate and quantify the association between the site of the fracture and AS by performing a meta-analysis.

METHODS

A systematic literature search was performed on Medline database from 1966 to August 15, 2016 and Embase database from 1980 to August 15, 2016. Studies were evaluated by 2 independent reviewers and quantitative estimates regarding the association between ankylosing spondylitis and the risk of any, hip, or vertebral fracture were presented. After the heterogeneity of selected studies was assessed by using Cochran I statistics, the random effect model was used to combine effect size. Publication bias was measured by Egger and Begg's regression tests.

RESULTS

A total of 6 articles were involved in our study. The results of meta-analysis revealed that AS was strongly associated with the risk of vertebral fracture (odds ratio [OR] = 4.25, 95% confidence interval [CI] = 1.07-7.42) and was not significantly associated with the risk of any fracture (OR=2.00, 95%CI = 0.94-3.06) or hip fracture (OR=1.28, 95%CI =0.16-2.40).

CONCLUSION

In the present study, a general knowledge of the association between AS and the risk of 3 kinds of fractures were presented, which could improve the ways of prevention of fracture in the patients with AS.

Spinal cord injury after traumatic spine fracture in patients with ankylosing spinal disorders

OBJECTIVE

Spinal cord injury (SCI) is a major complication of spinal fractures in patients with ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH). Due to the uncommon nature of these conditions, existing literature consists of relatively small case series without detailed neurological data. This study aims to investigate the incidence, predictors, and sequelae of SCI in patients with a traumatic fracture of the ankylosed spine.

METHODS

The study included all patients older than 18 years of age with AS or DISH who presented to two affiliated tertiary care centers between January 1, 1990, and January 1, 2016, and had a traumatic fracture of the spine. Factors associated with SCI after traumatic fracture were compared using Fisher’s exact tests. Logistic regression was used for the analysis of predictive factors for SCI. For the comparison of probability of survival between patients with and without SCI, Kaplan-Meier methodology was used.

RESULTS

One hundred seventy-two patients with a traumatic fracture of an ankylosed spine were included. Fifty-seven patients (34.1%) had an SCI associated with the fracture. The cervical spine was the most fractured region for patients both with (77.2%) and without (51.4%) SCI. A cervical fracture (odds ratio [OR] 2.70, p = 0.024) and a spinal epidural hematoma (SEH) after fracture (OR 2.69, p = 0.013) were predictive of SCI. Eleven patients (19.3%) with SCI had delayed SCI (range 8–230 days). Of 44 patients with SCI and sufficient follow-up, 20 (45.5%) had neurological improvement after treatment. Early and late complication rates were significantly higher (p = 0.001 and p = 0.004) and hospital stay was significantly longer (p = 0.001) in patients with SCI. The probability of survival was significantly lower in the SCI group compared with the non-SCI group (p = 0.006).

CONCLUSIONS

The incidence of SCI was high after fracture of the spine in patients with AS and DISH. Predictive factors for SCI after fracture were a fracture in the cervical spine and an SEH following fracture. One-fifth of the patients with SCI had delayed SCI. Patients with SCI had more complications, a longer hospital stay, and a lower probability of survival. Less than half of the patients with SCI showed neurological improvement.