A reduction method for anterior opening displacement in thoracolumbarvertebral fractures with diffuse idiopathic skeletal hyperostosis using the skull clamp-assisted position.

Diffuse idiopathic skeletal hyperostosis (DISH) frequently occurs in the spine, resulting in unstable fractures. Treating thoracolumbar fractures in patients with DISH is often difficult because the anterior opening of the vertebral body is exacerbated by dislocation in the prone position, making reduction difficult. In this study, we introduced a novel skull clamp-assisted positioning (SAP) technique. The patient is placed in a supine position with a skull clamp used in cervical spine surgery before surgery to prevent the progression of dislocation and to restore the patient's position. Using this method, the mean difference in local kyphosis angle improved from -2.9 (±8.4)° preoperatively to 10.9 (±7.7)° postoperatively. Furthermore, posterior displacement decreased from a preoperative mean of 5.5 (±4.3) mm to 0.3 (±0.7) mm postoperatively. Complications such as neurological sequelae, implant fracture, and surgical site infection were not observed through one year of postoperative follow-up. SAP may decrease invasiveness and complications. Longer-term studies and larger sample sizes are needed to establish long-term efficacy and benefits.

[Dysphagia as the main symptom in anterior cervical spine osteophytes (Forestier disease and cervical spondylosis deformans). Case reports and literature review]. / Disfagiya kak osnovnoi simptom pri perednikh osteofitakh sheinogo otdela pozvonochnika (bolezn' Forest'e i tservikal'nyi deformiruyushchii spondilez): obzor literatury i analiz klinicheskikh sluchaev.

Anterior cervical osteophytes are a fairly common X-ray finding in people over 50 years old. Incidence of dysphagia in patients with anterior osteophytes varies from 1% in those aged 40-60 years to 10.6% in patients over 60 years old. The most common causes of anterior cervical hyperosteophytosis causing dysphagia are cervical spondylosis deformans and Forestier disease. We present 2 clinical cases of spondylogenic dysphagia in cervical spondylosis deformans and Forestier disease. The review is devoted to the causes and diagnostic methods for dysphagia caused by anterior cervical osteophytes, as well as surgical options for this pathology. CONCLUSION: Microsurgical resection of anterior osteophytes is an effective method for dysphagia after ineffective therapy for 3 months. Microsurgical osteophytectomy provides stable regression of dysphagia with low recurrence rate.

Progressive spinal destruction secondary to minimal vertebral fracture in a patient with diffuse idiopathic skeletal hyperostosis: a case report.

Early operative fixation is widely recognized as essential for managing spinal fractures in patients with diffuse idiopathic skeletal hyperostosis (DISH). However, no report to date has addressed the occurrence of minimal vertebral fractures diagnosable only through magnetic resonance imaging (MRI) in these patients and the associated temporal changes in the fracture site. In this report, we describe a rare clinical case involving an 81-year-old man who developed progressive spinal destruction secondary to a minimal vertebral fracture. MRI showed minimum-intensity changes in the T12 vertebral body, whereas X-ray and computed tomography examinations showed DISH and no spinal fracture. Despite experiencing severe low back pain, the patient did not undergo operative therapy for 2 months, resulting in progressive spinal destruction. Spinal fusion with posterior instrumentation was performed, and the patient was followed for 1 year with no symptoms and good functional status. This case emphasizes the importance of clinicians being cautious to avoid overlooking and undervaluing minimal vertebral fractures diagnosable only through MRI in patients with DISH.

Risk of further surgery after decompression in patients with diffuse idiopathic skeletal hyperostosis extending to the lumbar segments: focus on the number of residual lumbar/lumbosacral and sacroiliac mobile segments.

PURPOSE: Patients with diffuse idiopathic skeletal hyperostosis (DISH) that extends to the lumbar segments (L-DISH) have a high risk of further surgery after lumbar decompression. However, few studies have focused on the ankylosis status of the residual caudal segments, including the sacroiliac joint (SIJ). We hypothesized that patients with more ankylosed segments beside the operated level, including the SIJ, would be at a higher risk of further surgery. METHODS: A total of 79 patients with L-DISH who underwent decompression surgery for lumbar stenosis at a single academic institution between 2007 and 2021 were enrolled. The baseline demographics and radiological findings by CT imaging focusing on the ankylosing condition of the residual lumbar segments and SIJ were collected. Cox proportional hazard analysis was conducted to investigate the risk factors for further surgery after lumbar decompression. RESULTS: The rate of further surgery was 37.9% during an average of 48.8 months of follow-up. Cox proportional hazard analysis demonstrated that the presence of fewer than three segments of non-operated mobile caudal segments was an independent predictor for further surgery (including both the same and adjacent levels) after lumbar decompression (adjusted hazard ratio 2.53, 95%CI [1.12-5.70]). CONCLUSIONS: L-DISH patients with fewer than three mobile caudal segments besides index decompression levels are at a high risk of further surgery. Ankylosis status of the residual lumbar segments and SIJ should be thoroughly evaluated using CT during preoperative planning.

The Effect of Posterior Lumbar Interbody Fusion in Lumbar Spine Stenosis with Diffuse Idiopathic Skeletal Hyperostosis: A Finite Element Analysis.

OBJECTIVE: Lumbar spinal canal stenosis (LSS) with diffuse idiopathic skeletal hyperostosis (DISH) can require revision surgery because of the intervertebral instability after decompression. However, there is a lack of mechanical analyses for decompression procedures for LSS with DISH. METHODS: This study used a validated, three-dimensional finite element model of an L1-L5 lumbar spine, L1-L4 DISH, pelvis, and femurs to compare the biomechanical parameters (range of motion [ROM], intervertebral disc, hip joint, and instrumentation stresses) with an L5-sacrum (L5-S) and L4-S posterior lumbar interbody fusion (PLIF). A pure moment with a compressive follower load was applied to these models. RESULTS: ROM of L5-S and L4-S PLIF models decreased by more than 50% at L4-L5, respectively, and decreased by more than 15% at L1-S compared with the DISH model in all motions. The L4-L5 nucleus stress of the L5-S PLIF increased by more than 14% compared with the DISH model. In all motions, the hip stress of DISH, L5-S, and L4-S PLIF had very small differences. The sacroiliac joint stress of L5-S and L4-S PLIF models decreased by more than 15% compared with the DISH model. The stress values of the screws and rods in the L4-S PLIF model was higher than in the L5-S PLIF model. CONCLUSIONS: The concentration of stress because of DISH may influence adjacent segment disease on the nonunited segment of PLIF. A shorter-level lumbar interbody fixation is recommended to preserve ROM; however, it should be used with caution because it could provoke adjacent segment disease.

Prognostic factors of balloon kyphoplasty for osteoporotic vertebral fractures with diffuse idiopathic skeletal hyperostosis.

OBJECTIVE: The authors aimed to determine the poor prognostic factors of balloon kyphoplasty for the treatment of fractures of the most distal or distal-adjacent vertebrae in ankylosing spines with diffuse idiopathic skeletal hyperostosis (DISH). METHODS: Eighty-nine patients with fractures of the most distal or distal-adjacent vertebrae of ankylosing spines with DISH were included and divided into two groups: those with (n = 51) and without (n = 38) bone healing 6 months postoperatively. Clinical evaluation included age, sex, time from onset to surgery, the visual analog scale score for low-back pain, and the Oswestry Disability Index (ODI). The VAS scores and ODI were measured both preoperatively and at 6 months postoperatively. Radiological evaluations included bone density; wedge angles of the fractured vertebrae in the supine and sitting positions on lateral radiographs; differences in the wedge angles (change in wedge angle); and the amount of polymethylmethacrylate used. RESULTS: The preoperative ODI, vertebral wedge angles in the supine and sitting positions, change in wedge angle, and amount of polymethylmethacrylate were significantly different between the two groups and were significantly associated with delayed bone healing in univariate logistic regression analysis. Multivariate logistic regression analysis showed that only a change in the wedge angle was significantly associated with delayed healing, with a cutoff value of 10°, sensitivity of 84.2%, and specificity of 82.4%. CONCLUSIONS: Treatment with balloon kyphoplasty alone should be avoided in patients with a difference ≥ 10° in the wedge angle of the fractured vertebrae between the supine and sitting positions.

Thoracic spondylotic myelopathy in diffuse idiopathic skeletal hyperostosis: a comparative study.

BACKGROUND: To explore the characteristics and clinical management of thoracic spinal stenosis with diffuse idiopathic skeletal hyperostosis (DISH). METHODS: The patients diagnosed with thoracic spondylotic myelopathy who underwent spinal decompression and fusion surgery in a single center between 2012 and 2020 were retrospectively analyzed. All the patients were followed up for at least 2 years. Patients were classified into DISH and non-DISH groups. Demographic, radiographic and clinical parameters were compared between the two groups. RESULTS: A total of 100 thoracic spondylotic myelopathy patients were included in the study. 22 patients were diagnosed with DISH. The proportion of male patients in the DISH group was higher, and the average BMI was larger. The incidence of upper thoracic vertebrae with ossification of posterior longitudinal ligament (OPLL) (P < 0.05) and lumbar spine with ossification of ligamentum flavum (OLF) was higher (P < 0.05) in DISH the group. The proportion of patients received staged surgery is higher in the DISH group (P < 0.1). There were no significant differences between the two groups in the amount of surgical bleeding, the ratio of cerebrospinal fluid leakage, the time duration of drainage tube placement and the JOA scores. CONCLUSION: Thoracic spinal stenosis with DISH occurred more in male patients with larger BMI. The posterior decompression and fusion surgery could achieve comparable satisfying clinical outcomes between DISH and non-DISH patients. More proportion of patients received staged surgery in the DISH group; the underline mechanism may be DISH caused more OPLL in the upper thoracic spine and more OLF in the lumbar spine because of mechanical stress.

Coexistence of flavum ligament ossification with diffuse idiopathic skeletal hyperostosis in the cervical spine: Review of literature and technical note starting from a rare case.

BACKGROUND: Cervical flavum ligament ossification (C-OLF) is very rare source of myeloradiculopathy. Less than 100 cases have been reported in modern English literature up to 2020. Association between C-OLF and Diffuse Idiopathic Skeletal Hyperostosis (DISH) at cervical level has never been described. METHODS: In this article we performed a systematic review about epidemiology, physiopathology, clinical and surgical management of C-OLF. Moreover, we research its possible association with other cervical spine ligament ossification and in particular with anterior longitudinal ligament ossification. We report a case of 73 years-old woman experiencing mild cervical myeloradiculopathy caused by C6-C7 C-OLF compression and coexistence of DISH at cervico-thoracic level. A brief technical note about intraoperative management of C-OLF has also been described. RESULT: Our research found 81 previous reported case of C-OLF. The coexistence of Posterior longitudinal ligament ossification has been reported in 21.3% of C-OLF case. Conversely, we reported the first case describing the association between DISH and C-OLF. Posterior surgical decompression is the only useful treatment providing good long-term functional outcome. Instrumentation should be tailored according to pre-operative findings. CONCLUSIONS: C-OLF is a rare source of myeloradiculopathy and it may coexists with DISH probably due to alteration in the cervical mechanical stress and tendency of bone formation in patients harboring coexistent ligament ossifications. According to our result, skip en-bloc microsurgical laminectomy is safe and less invasive method to avoid complication and to provide optimal cervical spinal cord and nerve decompression avoiding CSF-leak.

Zero-Profile Implant System for Treatment of Dysphagia Caused by Noncontiguous Anterior Cervical Osteophytes-A Case Report with Literature Review.

BACKGROUND: Esophageal cervical spondylosis is a rare type of cervical spondylosis which causes dysphagia. Surgical osteophyte resection is taken when conservative treatment does not respond. However, few reports on its operation and postoperative follow-up. We first present a case showing how the Zero-Profile implant system is utilized to treat dysphagia caused by noncontiguous anterior cervical osteophytes. CASE PRESENTATION: A patient with progressive dysphagia was referred to our department. Imaging examinations revealed a large diffuse idiopathic skeletal hyperostosis (DISH) related anterior osteophyte in C3/4, C6/7 and ossification of the anterior and posterior longitudinal ligaments. Anterior cervical osteophytectomy, discectomy, and fusion were performed on C3/4, C6/7. Two Zero-Profile implants were implanted. Postoperative dysphagia was significantly improved, and the patient was free to swallow large pills or solid foods at nine-years follow-up. CONCLUSION: Osteophyte excision can effectively treat esophageal cervical spondylosis, This case shows that fusion using the Zero-Profile implant system is a viable option for patients with potential cervical instability following osteophyte resection.

Surgical Treatment of Dysphagia Secondary to Anterior Cervical Osteophytes Due to Diffuse Idiopathic Skeletal Hyperostosis.

Diffuse idiopathic skeletal hyperostosis (DISH) is an ossifying and ankylosing skeletal condition that can be associated with DISH-related dysphagia in the case of cervical involvement. In contrast to most cases of dysphagia, which are managed conservatively, DISH-related dysphagia can be discouraging due to the progressive nature of DISH. We report two cases of DISH-related dysphagia that were treated with the surgical removal of osteophytes via an anterolateral approach. We were able to remove osteophytes using the bottleneck point as an anatomical landmark between the vertebral body and the bony excrescence. Patients' symptoms improved following osteophyte removal, without recurrence. In cases of DISH-related dysphagia, osteophyte removal using an osteotome could improve dysphagia safely and quickly.

Diffuse idiopathic skeletal hyperostosis of the cervical spine causing dysphagia and airway obstruction: an updated systematic review.

BACKGROUND AND CONTEXT: Diffuse idiopathic skeletal hyperostosis (DISH) is characterized by growing ossifications of spinal entheses and tendons, which may cause trachea and esophagus compression when located anteriorly in the cervical spine. PURPOSE: Our previous systematic review on the epidemiological and clinical knowledge of dysphagia and airway obstruction caused by cervical DISH was updated, with a focus on (surgical) treatment and outcomes. STUDY DESIGN: A systematic review of the literature was performed. METHODS: Publications in Medline and EMBASE from July 2010 to June 2021 were searched. Two investigators performed data extraction and study specific quality assessment. RESULTS: A total of 138 articles (112 case reports and 26 case series) were included, describing 419 patients with dysphagia and/or airway obstruction. The mean age of the patient group was 67.3 years (range: 35-91 years), and 85.4% was male. An evident increase of published cases was observed within the last decade. Surgical treatment was chosen for 66% of patients with the anterolateral approach most commonly used. The total complication rate after surgery was 22.1%, with 12.7% occurring within 1 month after intervention. Improvement of dysphagia was observed in 95.5% of operated patients. After a mean follow-up of 3.7 years (range: 0.4-9.0 years), dysphagia recurred in 12 surgically treated patients (4%), of which five patients had osteophyte regrowth. CONCLUSIONS: The number of published cases of dysphagia in patients with DISH has doubled in the last decade compared to our previous review. Yet, randomized studies or guidelines on the treatment or prevention on recurrence are lacking. Surgical treatment is effective and has low (major) complication rates. Common trends established across the cases in our study may help improve our understanding and management of dysphagia and airway obstruction in cervical DISH.

Diffuse Idiopathic Skeletal Hyperostosis Combined with Thoracic Spinal Stenosis Treated by Endoscopic Surgery: A Case Report.

CASE: A 48-year-old man presented to our facility with debilitating motor and sensory symptoms due to advanced T10-11 thoracic spinal stenosis secondary to diffuse idiopathic skeletal hyperostosis (DISH). The patient's condition was addressed with endoscopic spine surgery through a yet-to-be-reported interlaminar approach, and at the 12-month follow-up, his neurologic function was significantly improved. CONCLUSION: Select patients with symptomatic thoracic spinal stenosis secondary to DISH can be effectively managed with endoscopic spine surgery through an interlaminar approach by clinicians with extensive endoscopic spine experience.

Hyperextension-distraction fractures in ankylosing and spondylotic spines: injury profile and treatment results.

STUDY DESIGN: Case series study. PURPOSE: To describe demographic metrics, and clinical and radiographical outcomes of surgical treatment in patients with ankylosed spine (ASP) such as diffuse idiopathic skeletal hyperostosis (DISH) or ankylosing spondylitis (AS) and non-ankylosed spines (NAS) suffering from hyperextension-distraction spine fractures. METHODS: Patients diagnosed with hyperextension-distraction fractures between 2012 and 2020 were identified. A retrospective analysis of clinical and surgical data was performed. Similarities between patients with ASP and NAS were evaluated by Fisher's exact test. RESULTS: Of the 22 patients, 13 had ASP (10 patients with DISH, 3 AS) and nine NAS. Most of these injuries involved the thoracolumbar spine (45.4%). All patients with NAS presented some sign of spondylosis: facet joint degeneration, intervertebral osteochondrosis, and anterolateral osteophytes. None of the patients with NAS and 30.7% with ASP suffered low-energy mechanisms (p = .11). All the patients with NAS and 61% of the patients with ASP had associated injuries (p = .04). On average, the instrumented levels were four (range, 2-6), achieving a fusion rate of 94.7% in all groups. Most of the ASP and NAS presented post-operative complications respectively (p = .65). CONCLUSION: Hyperextension-distraction spine fractures are not unique in ASP. In patients with spondylosis and high-energy accidents, we should suspect those fractures and rule out associated injuries, fractures in other vertebral segments, and acute spinal cord injury. The four-level instrumentation achieved an effective fusion rate in all patients.

The impact of diabetes mellitus on spinal fracture with diffuse idiopathic skeletal hyperostosis: A multicenter retrospective study.

BACKGROUND: Patients with diffuse idiopathic skeletal hyperostosis (DISH) are susceptible to spinal column injuries with neurological deterioration. Previous studies indicated that the prevalence of diabetes mellitus (DM) in patients with DISH was higher than that in patients without DISH. This study investigates the impact of DM on surgical outcomes for spinal fractures in patients with DISH. METHODS: We retrospectively evaluated 177 spinal fractures in patients with DISH (132 men and 45 women; mean age, 75 ± 10 years) who underwent surgery from a multicenter database. The subjects were classified into two groups according to the presence of DM. Perioperative complications, neurological status by Frankel grade, mortality rate, and status of surgical site infection (SSI) were compared between the two groups. RESULTS: DM was present in 28.2% (50/177) of the patients. The proportion of men was significantly higher in the DM group (DM group: 86.0% vs. non-DM group: 70.1%) (p = 0.03). The overall complication rate was 22.0% in the DM group and 19.7% in the non-DM group (p = 0.60). Poisson regression model revealed that SSI was significantly associated with DM (DM group: 10.0% vs. non-DM group: 2.4%, Relative risk: 4.5) (p = 0.048). Change in neurological status, mortality rate, instrumentation failure, and nonunion were similar between both groups. HbA1c and fasting blood glucose level (SSI group: 7.2% ± 1.2%, 201 ± 67 mg/dL vs. non-SSI group: 6.6% ± 1.1%, 167 ± 47 mg/dL) tended to be higher in patients with SSI; however, there was no significant difference. CONCLUSIONS: In spinal fracture in patients with DISH, although DM was an associated factor for SSI with a relative risk of 4.5, DM did not negatively impact neurological recovery. Perioperative glycemic control may be useful for preventing SSI because fasting blood glucose level was high in patients with SSI.

Surgical management of Diffuse Idiopathic Skeletal Hyperostosis (DISH) causing secondary dysphagia (Narrative review).

Objectives: To summarize the current evidence on surgical treatment for large bridging osteophytes of the anterior cervical spine from Diffuse Idiopathic Skeletal Hyperostosis (DISH). Overview of Literature: In the current review, the surgical treatment of secondary dysphagia from DISH was the most useful treatment. We propose a treatment algorithm for management of this condition because currently there are only case reports and retrospective studies available. Methods: Literature search was performed using the MeSH terms "Anterior Cervical Osteophyte," "Diffuse Idiopathic Skeletal Hyperostosis (DISH)," and "Dysphagia" and "Treatment" for articles published between January 2000 and February 2020. PubMed search identified 117 articles that met the initial screening criteria. Detailed analysis identified the 40 best matching articles, following which the full inclusion and exclusion criteria left 11 articles for this review. Results: Incidence of secondary dysphagia was associated with DISH in elderly patients (average 65 years). The major clinical findings were dysphagia or respiratory compromise, with the most common level of bridging osteophytes of the cervical spine at C3-C5. There were 10 articles on surgical treatment involving anterior cervical osteophytectomy without fusion, 1 for multilevel cervical oblique corpectomy, 1 for anterior cervical discectomy with fusion plus plate, and 1 for anterior cervical osteophytectomy with stand-alone PEEK cage or plus plate. All the cases resulted in significant improvement without recurrence, with only 1 case having post-operative complications. Follow-up duration was 3-70.3 months. Conclusions: Surgical intervention for anterior cervical osteophytectomy appears to result in improved outcomes. However, there could be disadvantages concerning cervical spine motion if cervical osteophytectomy with cervical discectomy and fusion (ACDF) plus plate system is done.

Management of spine fractures in ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis: a challenge.

OBJECTIVE: Ankylosing spinal disorders (ASDs) such as ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) are complex diseases regarding diagnostics, treatment, and patient outcome, especially in trauma. Originating from rigid biomechanics and low bone quality in considerably comorbid patients, serious spinal injury requires thorough and immediate imaging and is frequently missed. The aim of this study was to evaluate patient characteristics as well as procedures in patients with ASD in order to identify the major particularities of treatment. METHODS: A total of 60 patients aged 78.5 ± 8.9 years were retrospectively included. Preoperative imaging as well as surgical treatment procedures and postoperative patient outcome were analyzed, including 30-day readmissions. RESULTS: CT imaging of the entire spine was performed within 24 hours after the initial trauma in 73.3% of patients. A delay in diagnostics (> 24 hours) occurred in 41.7% of patients transferred from primary care centers. At admission, 25.0% of patients had fracture-related neurological deficits (American Spinal Injury Association [ASIA] grades A and B in 4 patients, and ASIA grades C and D in 11 patients). A spinal epidural hematoma was found in 21.2% of patients and was symptomatic in 72.7% of those patients. Of the patients with fracture-related neurological deficits, 93.3% were operated on within 48 hours from symptom onset. One patient (1.7%) developed neurological deficits from diagnosis to surgery. Postoperatively, 18.3% of patients had surgical complications, and 76.7% of patients developed further medical issues, with pneumonia (38.3%), pulmonary decompensation (25.0%), and cardiac decompensation (20.0%) being the leading causes. The 30-day mortality rate was high at 10.0%. CONCLUSIONS: Treatment of patients with ASDs is complex. While surgical outcome is usually good, the multimorbid nature of these patients results in a high rate of major medical complications. If an ankylosing disease is suspected, MRI of the entire spine is mandatory. Upon diagnosis, treatment should be performed in centers capable of managing all aspects of the regular complications these patients will develop.

Anterior cervical surgery to treat diffuse idiopathic skeletal hypertrophic combined with cervical disc herniation: A case report.

RATIONALE: Diffuse idiopathic skeletal hyperostosis (DISH) is a skeletal disease characterized by calcification of anterolateral ligaments of the spine and the rest of the body. DISH combined with disc herniation induces complex symptoms and is more difficult to treat. Here, we describe a complicated case of a patient diagnosed with DISH as well as cervical disc herniation that was successfully treated using anterior cervical surgery. PATIENTS CONCERN: A 69-year-old Asian male experienced dysphagia and weakness in his left limbs. He also experienced a stiff neck and right slant over a 6-month period. DIAGNOSIS: An X-ray revealed calcification of the C4-7 vertebral front edge and a narrowed intervertebral space between C5/6. Coronal and sagittal computerized tomography (CT) and magnetic resonance imaging (MRI) both showed compression of the spinal cord at the cervical 5/6. Esophagography revealed that osteophytes in the anterior margin of vertebral body (C4-C7) oppressed the esophagus. INTERVENTIONS: An operation focused on anterior cervical C5/6 disc fusion and anterior vertebral C4-7 osteophyte removal was performed. OUTCOMES: After the operation, X-ray and CT showed that most osteophytes were removed and spinal cord compression was relieved. One day following the operation, both dysphagia and numbness in limbs were improved. Strong recovery was observed at the three-month follow-up exam. LESSONS: This complex DISH combined with disc herniation case is rarely observed in patients. Anterior cervical disc fusion and anterior vertebral osteophyte removal were effective treatment measures. This case study provides insight into treating cases presented with cervical spine complications associated with DISH combined with other ailments.

Percutaneous, PMMA-augmented, pedicle screw instrumentation of thoracolumbar ankylotic spine fractures.

INTRODUCTION: Fractures in the ankylotic spine may have an insidious presentation but are prone to displace with devastating consequences. The long lever arm of ankylosed spine fragments may lead to pulmonary and great vessel injury and is difficult to adequately immobilize. Conservative treatment will produce in many cases poor outcomes with high morbidity and mortality. Open surgical treatment is also fraught with technical difficulties and can lead to major blood loss and prolonged operative times. In recent years, percutaneous instrumentation of non-ankylotic spine fractures has gained popularity, producing similar outcomes to open surgery with shorter operative times and reduced blood loss and hospital length of stay. We describe our experience implementing these techniques in ankylotic spine patients. METHODS: We retrospectively retrieved from our hospital's electronic health records all patients treated for thoracolumbar spine fractures between 2008 and 2015 with a diagnosis of ankylosing spondylitis (AS) or diffuse idiopathic skeletal hyperostosis (DISH). Operative and postoperative data, results, and complications were tabulated, and radiographic parameters were evaluated. RESULTS: Twenty-four patients with ankylotic spine disease underwent percutaneous augmented instrumentation between 2008 and 2015. The mean age was 76. All patients had at least one comorbidity. The mean number of ankylosed levels was 14. Mean operative time was 131 min. The average postoperative hemoglobin decrease was 1.21 gr/%, with only 4 patients requiring blood transfusion. 45.8% of the patients had postoperative medical complications. One patient (4.2%) had a superficial postoperative infection, and one patient died in hospital. The average hospital length of stay was 14.55 days. All patients retained their preoperative ASIA grades, and 3 improved one grade. All patients united their fractures without losing reduction. CONCLUSIONS: PMMA-augmented percutaneous instrumentation is an attractive surgical option for this difficult patient subset, especially when compared to other available current alternatives.

Usefulness of dynamic stabilisation with mobile percutaneous pedicle screw for thoracic vertebral fractures in diffuse idiopathic skeletal hyperostosis.

We report a case of vertebral fracture with diffuse idiopathic skeletal hyperostosis (DISH) who underwent posterior dynamic stabilisation using mobile percutaneous pedicle screws (PPS) with 1 above-1 below and obtained good bone fusion. A 76-year-old man experienced severe low back pain after he fell backward 1 m off a stepladder during work. A 12th thoracic vertebral fracture with DISH was observed. As the fractured part was unstable due to a three-column injury, and the conservative treatment of resting was not successful, posterior dynamic stabilisation with a mobile PPS between T11-L1 was performed the 38th day after injury. Immediately after surgery, a fracture gap was observed, but 5 months later, vertebral body height was shortened by about 4 mm, and good bone fusion was observed without loosening of the screw. The mobile PPS flexibly adapts to spinal plasticity and may be useful for bone union in vertebral fractures associated with DISH.