Jan Göthlin

Osteoporosis in ankylosing spondylitis - prevalence, risk factors and methods of assessment

IntroductionOsteoporosis can be a complication of ankylosing spondylitis (AS), but diagnosing spinal osteoporosis can be difficult since pathologic new bone formation interferes with the assessment of the bone mineral density (BMD). The aims of the current study were to investigate prevalence and risk factors for reduced BMD in a Swedish cohort of AS patients, and to examine how progressive ankylosis influences BMD with the use of dual-energy x-ray absorptiometry (DXA) of the lumbar spine in different projections.MethodsMethods of assessment were questionnaires, back mobility tests, blood samples, lateral spine radiographs for syndesmophyte grading (mSASSS), DXA of the hip, radius and lumbar spine in anteroposterior (AP) and lateral projections with estimation of volumetric BMD (vBMD).ResultsAS patients (modified New York criteria), 87 women and 117 men, mean age 50 ± 13 years and disease duration 15 ± 11 years were included. According to World Health Organization (WHO) criteria 21% osteoporosis and 44% osteopenia was diagnosed in patients > = 50 years. Under age 50 BMD below expected range for age was found in 5%. Interestingly lateral lumbar DXA showed significantly lower BMD and revealed significantly more cases with osteoporosis as compared with AP DXA. Lumbar vBMD was not different between sexes, but women had significantly more lumbar osteoporosis measured with AP DXA (P < 0.001). Men had significantly higher mSASSS (P < 0.001). Low BMD was associated with high age, disease duration, mSASSS, Bath Ankylosing Spondylitis Metrology Index (BASMI), inflammatory parameters and low body mass index (BMI). Increasing mSASSS correlated significantly with decreasing lateral and volumetric lumbar BMD, while AP lumbar BMD showed tendency to increase.ConclusionsOsteoporosis and osteopenia is common in AS and associated with high disease burden. Lateral and volumetric lumbar DXA are more sensitive than AP DXA in detecting osteoporosis and are less affected by syndesmophyte formation.

Vertebral Fractures in Ankylosing Spondylitis Are Associated with Lower Bone Mineral Density in Both Central and Peripheral Skeleton

Objective. To study the prevalence and risk factors for vertebral fractures (VF) in ankylosing spondylitis (AS) and the relation between VF, measures of disease activity, and bone mineral density (BMD) in different measurement sites. Methods. Patients with AS (modified New York criteria) underwent examination, answered questionnaires, and gave blood samples. Lateral spine radiographs were scored for VF (Genant score) and syndesmophyte formation through modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). BMD was measured with dual-energy x-ray absorptiometry in the hip, radius, and lumbar spine in anteroposterior and lateral projections with estimation of volumetric BMD (vBMD). Results. Two hundred four patients (57% men) with a mean age of 50 ± 13 years and disease duration 15 ± 11 years were included. VF were diagnosed in 24 patients (12%), but were previously noted clinically in only 3 of the 24. Patients with VF were significantly older (p = 0.004), had longer disease duration (p = 0.011), higher Bath Ankylosing Spondylitis Metrology Index (p = 0.011), mSASSS (p = 0.035), and Bath Ankylosing Spondylitis patient global score-2 (BASG-2) (p = 0.032) and were more often smokers (p = 0.032). All women with a VF were postmenopausal. BMD was significantly lower at all measuring sites in the patients with VF. In logistic regression, high BASG-2, low BMD in femoral neck, and low lumbar vBMD were independently associated with presence of VF. Conclusion. VF in AS are common but are often not diagnosed. VF are associated with advanced age, longstanding disease, impaired back mobility, syndesmophyte formation, and lower BMD in both the central and peripheral skeleton. BMD in the femoral neck, total hip, and estimated vBMD showed the strongest association with VF.

The role of CT in the diagnosis of sacro-iliitis

Objective: Ankylosing spondylitis is a progressive, debilitating disease in which early diagnosis and early treatment can improve the prognosis. Radiographic confirmation is essential for diagnosis but conventional radiography has not proved useful, particularly in the early course of the disease. The aims of this study were to correlate the findings at conventional radiography with those at CT, and to correlate the duration of clinical symptoms with the radiological findings Material and Methods: Forty patients with clinical sacro-iliitis and 13 controls were evaluated by means of conventional radiography and CT Results: Conventional radiography was positive in 10/40 patients and CT in 30/40 patients. Conventional radiography was positive in only 2/14 patients with a symptom duration of less than 2 years while CT was positive in 10/14 such patients Conclusion: The study demonstrated a considerably higher sensitivity in CT than in conventional radiography in detecting the subtle changes necessary for the radiological diagnosis of sacro-iliitis, particularly in cases of short duration. CT allows an early start to be made in treatment with a consequently improved prognosis. The use of conventional radiography cannot be recommended because its low sensitivity delays diagnosis in many instances

The validity of the new york radiological grading criteria in diagnosing sacroiliitis by computed tomography

Background: Sacroiliitis in ankylosing spondylitis has frequently been graded radiographically using the New York (NY) criteria, which also have been applied in computed tomography (CT). Purpose: To validate the grading of the NY criteria in CT of the sacroiliac joints. Material and Methods: With the aid of the NY criteria, assessment of inflammatory and degenerative changes was made in 1304 CT studies. Assessment included erosions, the distribution, type, and width of sclerosis, and the involvement of the joints in sacroiliitis, as well as of normal anatomic variants such as joint space width and shape. Results: There was definite radiological sacroiliitis in 420 joints in 251 patients. Among these, more than two-thirds of the joint was involved in 71.0% of the affected joints. Sclerosis of the ilium was much more prevalent than sacral sclerosis. With increasing NY grade, iliac sclerosis, width, and extent increased, transition from sclerosis to normal bone became indistinct, and the structure of sclerosis was more inhomogeneous. Erosions of the joint surfaces were localized predominantly on the iliac side. Conclusion: Only erosions seem to be a valid solitary diagnostic sign. Solitary erosions need supplemental evidence from other inflammatory signs. Inflammatory sclerosis may be distinguished from degenerative sclerosis, and can sometimes support early diagnosis. Joint space width, joint shape, bone mineral content, or enthesopathy have no place in sacroiliitis diagnosis on CT. The NY criteria are not ideal for use with CT. A practical classification of sacroiliitis on CT is proposed, with a grading of no disease, suspected disease, and definite disease.

Endovascular Training with Animals versus Virtual Reality Systems: An Economic Analysis

PURPOSE To assess the relative costs of a virtual reality (VR) laboratory and an animal laboratory for endovascular skills training. MATERIALS AND METHODS Cost data extracted from a previous experiment was used to perform a financial analysis according to the guidelines published by the National Institutes of Health. The analysis compared the purchase or rental of a Procedicus Vascular Interventional System Trainer to the rental of an animal laboratory. RESULTS The VR laboratory course cost

Bone bruise, lipohemarthrosis, and joint effusion in CT of non-displaced hip fracture.

3,434 per trainee versus

Role of Wnt/β-catenin and RANKL/OPG in bone healing of diabetic Charcot arthropathy patients.

4,634 in the animal laboratory according to the purchase-versus-rental analysis. The cost ratio was 0.74 in favor of the VR laboratory. Cost ratio sensitivity analysis ranged from 0.25 in favor of the VR laboratory to 2.22 in favor of the animal laboratory. The first-year potential savings were

The Utility of Digital Linear Tomosynthesis Imaging of Total Hip Joint Arthroplasty with Suspicion of Loosening: A Prospective Study in 40 Patients

62,410 assuming exclusive use of the VR laboratory. The 5-year training savings totaled

Observer variation for radiography, computed tomography, and magnetic resonance imaging of occult hip fractures

390,376, excluding the

Computed tomography compared to magnetic resonance imaging in occult or suspect hip fractures. A retrospective study in 44 patients

60,000 residual value of the simulator. Simulator rental reduced the course price to