Diffuse Idiopathic Skeletal Hyperostosis Is Associated with Lower Lung Volumes in Current and Former Smokers

Pelvic Roll Back Can Trigger Functional Psoas Impingement in Total Hip Arthroplasty

In most cases, impingement of the iliopsoas tendon after total hip arthroplasty is caused by acetabular component retroversion. The present case report describes a patient with functional iliopsoas impingement following total hip arthroplasty. With increasing flexibility of the hip joint after surgery, the functional adjustment to the stiff thoracolumbar spine in this patient with diffuse idiopathic skeletal hyperostosis resulted in progressive pelvic roll back. This roll back resulted in a functional iliopsoas impingement as the psoas tendon travels over the front of the pecten ossis pubis. Since excessive roll back is usually also addressed in primary total hip arthroplasty by decreasing anteversion of the acetabular component, surgeons should be aware to avoid the combination of roll back and decreased anteversion and their potential impact on iliopsoas impingement.

A Scoring System for Anterior Longitudinal Ligament Ossification of the Lumbar Spine in Diffuse Idiopathic Skeletal Hyperostosis: Relationship Between the Extent of Ligament Ossification and the Range of Motion

STUDY DESIGN

Retrospective observational study.

OBJECTIVE

To investigate the relationship between the extent of ligament ossification and the range of motion (ROM) of the lumbar spine and develop a new scoring system.

METHODS

Forty-three patients (30 men and 13 women) with lumbar spinal canal stenosis who underwent decompression from January to December 2018. Ligament ossification at L1/2 to L5/S was assessed on plain X-ray (Xp) and computed tomography (CT) using a modified Mata scoring system (0 point: no ossification, 1 point: ossification of less than half of the intervertebral disc height, 2 points: ossification of half or more of the intervertebral disc height, 3 points: complete bridging), and the intra-rater and inter-rater reliability of the scoring was assessed. The relationship of the scores with postoperative lumbar ROM was investigated.

RESULT

Intra-rater reliability was high (Cronbach's α was 0.74 for L5/S on Xp but 0.8 or above for other sections), as was inter-rater reliability (Cronbach's α was 0.8 or above for all the segments). ROM significantly decreased as the score increased (scores 1 to 2, and 2 to 3). A significant moderate negative correlation was found between the sum of the scores at L1/2-L5/S and the ROM at L1-S (ρ = - 0.4493, P = 0.025).

CONCLUSION

Our scoring system reflects lumbar mobility and is reproducible. It is effective for assessing DISH in fractures and spinal conditions, and monitoring effects on treatment outcomes and changes over time.

The Prevalence and Characteristics of Diffuse Idiopathic Skeletal Hyperostosis (DISH): A Cross-Sectional Study of 1519 Japanese Individuals

Background: Diffuse idiopathic skeletal hyperostosis (DISH) is a pathology characterized by enthesis ossification, but there have been few reports on epidemiological surveys. This report presents a cross-sectional survey of DISH from thoracic to sacral spine in patients at the tertiary emergency medical center. Methods: The patients were divided into DISH (+) group and DISH (−) group for a retrospective comparative study. The primary outcome measures were the frequency of DISH and the patient demographic data, the secondary outcome measures were the previous medical history (diabetes mellitus, cardiovascular disease), the extent of aortic calcification, the frequency of hyperostosis around the costovertebral joint and the mortality rate within 3 months of the initial examination. Results: This survey examined a total of 1519 patients. There were 265 cases (17.4%) in the DISH (+) group and 1254 cases in DISH (−) group. The prevalence of DISH was concentrated at the thoracolumbar junction, particularly at T9. The mean age, ratio of male and hyperostosis around the costovertebral joint were significantly higher in the DISH (+) group (p < 0.001), but there was no significant difference in other variables. Conclusions: The pathology of DISH might involve the effects of age-related changes or biomechanical effects.

Progression of Ossification of the Anterior Longitudinal Ligament Associated With Diffuse Idiopathic Skeletal Hyperostosis by Age: A Study of Computed Tomography Findings Over 5 Years

STUDY DESIGN

Observational study.

OBJECTIVE

To investigate whether the progression of anterior longitudinal ligament ossification varies by age among patients with diffuse idiopathic skeletal hyperostosis (DISH).

METHODS

Of the patients who underwent computed tomography (CT) of the thoracic to pelvic region at least twice from 2009 to 2018, 191 who underwent CT at an interval of 5 years and 0 months to 5 years and 2 months were enrolled (87 men and 104 women). Sex, age at the time of the first CT scan, the presence/absence of DISH, level of complete vertebral body fusion associated with DISH, and extent of ligament ossification using the modified Mata scoring system were investigated.

RESULTS

DISHs were detected in 53 (27.7%) of 191 patients. The score of ligament ossification increased over time in 35 (66%) of 53 patients; 93 intervertebral spaces were affected. The percentage of completely fused intervertebral spaces increased by 6.7% from 31.3% to 38.0% over time. The increase in score for all intervertebral spaces in individual patients was significantly greater in the ≤70 years old group (2.7 ± 2.8 points, n = 28) than in the ≥71 years old group (1.2 ± 1.4 points; n = 25; P = .028). The mean age of patients with a recorded score that increased by ≥1 point was 67.4 years and that of patients without any change in the score was 73.3 years (P = .036). Thus, patients with recorded changes in the score were younger.

CONCLUSION

During the approximately 5-year period, ossification progressed more in younger patients than in older patients.

Two Cases of Severe Type 2 Respiratory Failure Associated with Diffuse Idiopathic Skeletal Hyperostosis

Diffuse idiopathic skeletal hyperostosis (DISH) is a non-inflammatory process characterized by hyperostosis at tendon insertions and around joint capsules and ossification of the anterior longitudinal ligament of the spine. The flexibility of the spinal column is reduced in DISH and affects the movement of the thorax, leading to restrictive ventilatory function. In this report, we describe the first two cases of severe type 2 (hypercapnic) respiratory failure associated with DISH. Two older men presented with histories of shortness of breath. Radiography of the spine revealed DISH with coexisting ankylosis of the costovertebral joints. The patients’ thoracic motion was severely restricted, reducing the mechanism of lung expansion to diaphragm contraction only. Both patients required non-invasive positive-pressure ventilation therapy to cope with their conditions. Our report sheds light on the risk of potentially life-threatening respiratory manifestations of DISH among older adults.

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.

Subjects with diffuse idiopathic skeletal hyperostosis have an increased burden of coronary artery disease: An evaluation in the COPDGene cohort

BACKGROUND AND AIMS

Diffuse idiopathic skeletal hyperostosis (DISH) is a common incidental finding on medical imaging and often thought to be benign. Our objective was to investigate whether DISH is associated with coronary artery disease as measured with the coronary artery calcification (CAC) score in a large cohort of current and former smokers.

METHODS

In a subset of subjects from the COPDGene study, DISH was scored by a minimum of two independent readers if there were four adjacent levels of flowing osteophytes and a third reader adjudicated discrepancies. CAC was calculated using a modified Agatston method. Associations of DISH with the presence and extent of CAC were analyzed with and without adjustment for COPD and known atherosclerotic risk factors, including age, sex, race, diabetes, hypertension, high cholesterol, body mass index and smoking.

RESULTS

DISH was present in 361 subjects (13.2%) from a total group of 2728. Median (interquartile range) Agatston was 81 (0-329) in DISH subjects compared to 0 (0-94 in subjects without DISH (p < 0.001). DISH prevalence was 8.8% in CAC = 0, 12.8% in CAC1-100, 20.0% in CAC100-400 and 24.7% in CAC.400. Subjects with DISH had a significantly higher risk of having coronary artery calcifications; OR [CI95%] 1.37[1.05-1.78] (p=0.019) after correction for age, gender, race, COPD and atherosclerotic risk factors.

CONCLUSIONS

Subjects with DISH, a common musculoskeletal disorder involving bone formation anterior to the spine, have an increased burden of coronary artery disease, and therefore DISH may be a more relevant incidental finding than commonly thought.

Diffuse Idiopathic Skeletal Hyperostosis in Smokers and Restrictive Spirometry Pattern: An Analysis of the COPDGene Cohort

OBJECTIVE

Diffuse idiopathic skeletal hyperostosis (DISH) is a condition characterized by bony proliferation at sites of tendinous and ligamentous insertions in the spine. Spinal mobility is reduced in DISH and may affect movement in the thorax, potentially leading to restrictive pulmonary function. This study investigated whether DISH is associated with restrictive spirometric pattern (RSP) in former and current smokers.

METHODS

Participants (n = 1784) with complete postbronchodilator spirometry who did not meet spirometric criteria for chronic obstructive pulmonary disease (COPD) at time of enrollment in the COPDGene study were included in this study. Subjects were classified as RSP if they had forced expiratory volume in 1 s(FEV1) to forced vital capacity (FVC) ratio > 0.7 with an FVC < 80%. Computed tomography (CT) scans were scored for the presence of DISH in accordance with the Resnick criteria. Chest CT measures of interstitial and alveolar lung disease, clinical symptoms, health surveys, and 6-min walking distance were recorded. Uni- and multivariable analyses were performed to test the association of DISH with RSP.

RESULTS

DISH was present in 236 subjects (13.2%). RSP was twice as common in participants with DISH (n = 90/236, 38.1%) compared to those without DISH (n = 301/1548, 19.4%; p < 0.001). In multivariable analysis, DISH was significantly associated with RSP (OR 1.78; 95% CI 1.22-2.60; p = 0.003) after adjusting for potential confounders. The RSP group with and without DISH had significantly worse spirometry, dyspnea, St. George's Respiratory Questionnaire score, BODE index (Body mass index, airflow Obstruction, Dyspnea and Exercise capacity), and Medical Outcomes Study Short Form-36 questionnaire score.

CONCLUSION

In heavy smokers with an FEV1/FVC ratio > 0.70, DISH is associated with RSP after adjustment for intrinsic and extrinsic causes of restrictive lung function. (Clinical trial registration number: NCT00608764.).

Bone mineral density changes over time in diffuse idiopathic skeletal hyperostosis of the thoracic spine

Diffuse idiopathic skeletal hyperostosis (DISH) is an increasingly prevalent ankylosing condition. Patients with DISH have an increased risk of spinal fractures, hypothetically the result of biomechanical changes in the spine. The aim of this study was to analyze the occurrence of biomechanical stress shielding in patients with DISH. To do this, bone mineral density (BMD) was measured longitudinally in the vertebral bodies of subjects with and without DISH and in the newly formed bone of subjects with DISH. The presence of DISH was evaluated using Resnick criteria on two chest computed tomography (CT) scans taken at least 2.5 years apart from subjects over 50 years of age. Three groups were identified: pre-DISH (individuals who developed DISH after the first CT scan), definite DISH (individuals who had DISH on both CT scans), and controls (individuals with no DISH). Hounsfield units (HU) were measured in the newly formed bone and in predefined anterior and posterior portions of the involved vertebral bodies. Mean BMD of the newly formed bone increased significantly (mean ΔHU 137.5; p < 0.01) during a mean interval of 5 years in the cranial, middle, and caudally involved vertebral segments of both DISH groups. Mean BMD of the vertebral bodies in the ankylotic segments in the DISH groups did not significantly differ from that of the non-ankylotic vertebral bodies of the same subject. In contrast to our hypothesis, the HU value of the vertebral body decreased more in the control group than in the DISH groups; however, statistical significance was only reached at the cranial level in the anterior part of the vertebral body (p = 0.048). Our data suggest that 1) vertebral BMD is not influenced by the presence of DISH and 2) increased spinal stiffness may play a more important role than vertebral BMD in the increased fracture risk of and the typical fracture patterns observed in individuals with DISH.

The Natural Course of Diffuse Idiopathic Skeletal Hyperostosis in the Thoracic Spine of Adult Males

Objective.

Diffuse idiopathic skeletal hyperostosis (DISH) is characterized by flowing bony bridges on the right side of the spine. Knowledge of the development of these spinal bridges is limited. The current longitudinal computed tomography (CT) study was designed to bridge this gap.

Methods.

Chest CT scans from elderly males with 2 scans (interval ≥ 2.5 yrs) were retrospectively included. Using the Resnick criteria, a pre-DISH group and a definite DISH group were identified. A scoring system based on the completeness of a bone bridge (score 0–3), extent of fluency, and location of the new bone was created to evaluate the progression of bone formation.

Results.

In total, 145 of 1367 subjects were allocated to the DISH groups with a mean followup period of 5 years. Overall prevalence of a complete bone bridge increased in the pre-DISH group (11.3% to 31.0%) and in the definite DISH group (45.0% to 55.8%). The mean bridge score increased significantly in both the pre-DISH and definite DISH group (p < 0.001). The new bone gradually became more flowing and expanded circumferentially.

Conclusion.

Over the mean course of 5 years, the new bone developed from incomplete, pointy bone bridges to more flowing complete bridges. This suggests an ongoing and measurable bone-forming process that continues to progress, also in established cases of DISH.

Classification criteria for diffuse idiopathic skeletal hyperostosis: a lack of consensus

Objectives

DISH is a condition characterized by flowing ossifications of the spine with or without ossifications of entheses elsewhere in the body. Studies on the prevalence and pathogenesis of DISH use a variety of partly overlapping combinations of classification criteria, making meaningful comparisons across the literature difficult. The aim of this study was to systematically summarize the available criteria to support the development of a more uniform set of diagnostic/classification criteria.

Methods

A search was performed in Pubmed, Embase, Cochrane Library and Web of Science using the term DISH and its synonyms. Articles were included when two independent observers agreed that the articles proposed a new set of classification criteria for DISH. All retrieved articles were evaluated for methodological quality, and the presented criteria were extracted.

Results

A total of 24 articles met the inclusion criteria. In all articles, spinal hyperostosis was required for the diagnosis of DISH. Peripheral, extraspinal manifestations were included as a (co-)requirement for the diagnosis DISH in five articles. Most discrepancies revolved around the threshold for the number of vertebral bodies affected and to defining different developmental phases of DISH. More than half of the retrieved articles described a dichotomous set of criteria and did not consider the progressive character of DISH.

Conclusion

This systematic review summarizes the available different classification criteria for DISH, which highlights the lack of consensus on the diagnosis of (early) DISH. Consensus criteria, including consecutive phases of new bone formation that characterize DISH, can be developed based upon established diagnostic/classification criteria.