Spondyloarthropathies: ankylosing spondylitis and psoriatic arthritis

As advances in the treatment of ankylosing spondylitis continue, TNF-alpha blocking agents may eventually be used as a first-line treatment. MR imaging could then be used to aid in the early diagnosis of ankylosing spondylitis by identifying early sacroiliitis, followed by immediate initiation of treatment to prevent the progression of the disease with its accompanying morbidities. Currently, radiographic identification of sacroiliitis remains the mainstay in diagnosing ankylosing spondylitis. In ankylosing spondylitis and psoriasis, MR imaging can demonstrate areas that are undergoing active inflammatory changes and enthesitis, aiding in the diagnosis of a spondyloarthropathy.     

The other arthritides. Roentgenologic features of osteoarthritis, erosive osteoarthritis, ankylosing spondylitis, psoriatic arthritis, Reiter's disease, multicentric reticulohistiocytosis, and progressive systemic sclerosis

Osteoarthritis may be divided into primary generalized and secondary forms. Primary generalized osteoarthritis is characterized by narrowing of cartilage, marginal osteophytes, and absence of erosions. The most common sites of involvement are the distal interphalangeal joints of the fingers and the first carpometacarpal joint. Secondary osteoarthritis also results in narrowing of cartilage in the absence of erosions, but in regions of mechanical stress. Erosive osteoarthritis affects predominantly the proximal and distal interphalangeal joints, and evolves into bony fusion in 12 to 15 per cent of cases, about the same percentage of interphalangeal bony fusion that occurs in psoriatic arthritis. Ankylosing spondylitis predominates in the axial skeleton where it eventually leads to fusion of the vertebrae and sacroiliac joints. Psoriatic arthritis combines many features of rheumatoid arthritis, in which synovial inflammation predominates, and ankylosing spondylitis, in which ligamentous inflammation predominates. The hands and feet are involved to an equal extent, and in 20 per cent of patients the disorder also involves the sacroiliac joints and spine. Reiter's disease, like psoriatic arthritis, differs from ankylosing spondylitis in its inconstant involvement of the spine and greater involvement of peripheral joints. Reiter's disease differs from psoriatic arthritis in its predominant involvement of the lower limbs, particularly the feet, with relative sparing of the hands and wrists. Multicentric reticulohistiocytosis is a rare disorder in which polyarthritis usually precedes the onset of nodular cutaneous eruptions, a fact that emphasizes the importance of early roentgenologic recognition. The interphalangeal joints are the predominant sites of involvement in the hands, but eventually all of the synovium lined joints become affected, with arthritis mutilans the end result in one third of cases. The erosions are strikingly symmetrical and well circumscribed, and accompanying osteoporosis is disproportionately mild. Progressive systemic sclerosis is characterized by atrophy and dystrophic calcifications in the soft tissues, ultimately leading to joint deformities and resorption of the terminal tufts of the phalanges. Resorption of bone occurs at other sites as well, and marginal erosions may develop in the metacarpophalangeal and interphalangeal joints of the hands.     

Clinical and radiographic abnormalities in ankylosing spondylitis: a comparison of men and women.

A clinical and radiographic study of 98 patients with definite ankylosing spondylitis (Rome criteria) was undertaken to evaluate differences in men and women with the disease. Clinical manifestations which were atypical in the 18 female patients when compared to those of the men included older age of disease onset, higher incidence of initial and subsequent peripheral joint disease, more common cervical spine symptomatology, and milder disease course. Radiographic differences in the women included a high incidence of cervical spine abnormalities, a combination of cervical spine and sacroiliac joint alterations with a normal intervening thoracic and lumbar segment, and frequent and severe osteitis pubis.     

Comparison of radiographic abnormalities of the sacroiliac joint in degenerative disease and ankylosing spondylitis.

Degenerative disease of the sacroiliac joint is common in middle-aged and elderly patients. Its radiographic features simulate those of ankylosing spondylitis. Interosseous space narrowing, subchondral sclerosis, and osteophytosis are apparent. Although intraarticular bony ankylosis is generally absent, anterior paraarticular bridging osteophytes resemble true osseous fusion of the joint cavity on frontal radiographs. Focal sclerosis in degenerative disease is most common on the superior and inferior margins of the articular cavity and can usually be differentiated from that accompanying ankylosing spondylitis and osteitis condensans ilii.     

Rheumatoid arthritis: similarity of radiographic abnormalities in men and women

To test the hypothesis that there are significant differences in the radiographic appearance of rheumatoid arthritis between men and women, the authors blindly evaluated bilateral hand and wrist radiographs in 32 men with definite rheumatoid arthritis and 32 age- and disease duration-matched women (mean age, 56.4 years; mean disease duration, 10.5 years). Radiographically, disease distribution and severity were identical in these matched groups. Superimposed osteoarthritis was frequent in both groups and related to age. Ill-defined bone proliferation was present in 13 of 64 hands in both groups. Cystic changes and well-defined erosions were present in 12 of 64 male hands and six of 64 female hands, but this difference was not statistically significant. In women, presence of cysts and bone proliferation was related to disease duration, whereas men exhibited these atypical features independent of disease duration. There was no statistically significant difference in the frequencies of typical and atypical features of rheumatoid arthritis between the two sexes, and the authors postulate that previously reported differences relate to patient selection and lack of adequate matching.     

The chest radiograph in ankylosing spondylitis.

In a study of 42 patients with ankylosing spondylitis, upper lobe fibrosis was present in six (14-3%) patients. All the patients with upper lobe fibrosis had total spinal ankylosis, and half showed peripheral joint involvement. A further 13 patients (30-9%) had other focal pulmonary abnormalities compared with only six (14-3%) of a group of age-matched controls. There was no correlation between the radiological extent of the disease (spinal changes and pulmonary involvement) and any of the haematological or biochemical parameters measured. Treatment with radiotherapy was not responsible for these changes.     

Imaging features of psoriatic arthritis and Reiter's syndrome

Psoriatic arthritis and Reiter's Syndrome are seronegative spondyloarthropathies with characteristic, yet nonspecific, radiographic findings. Radiographic diagnosis is based upon recognition of the classic morphologic changes and knowledge of the articular distribution. Other imaging modalities such as computed tomography (CT), radionuclide imaging, magnetic resonance (MR) imaging, and ultrasonography are also utilized and play specific roles in the evaluation of Psoriatic arthritis and Reiter's Syndrome.     

Case report: CT and MRI of the cauda equina syndrome in ankylosing spondylitis.

The clinical and radiological findings in a patient with long-standing ankylosing spondylitis who developed the clinical features of a cauda equina syndrome are presented. CT and MRI revealed characteristic expansion of the lumbar spinal canal with scalloping of the laminae and spinous processes related to the presence of dorsal dural diverticulae. MRI permitted confident exclusion of other intradural pathology without recourse to invasive investigations.     

Magnetic resonance imaging of cauda equina syndrome in long-standing ankylosing spondylitis

The cauda equina syndrome is an uncommon complication of long-standing ankylosing spondylitis and its aetiology is controversial. We report a case of the cauda equina syndrome, erosion of the posterior elements of the lumbar spine and traction of the lumbar nerve roots because of multiple dural diverticula in a patient with long-standing ankylosing spondylitis. Magnetic resonance imaging is valuable in excluding other spinal lesions. Extensive dural diverticula formation is characteristic of ankylosing spondylitis and has the potential to provide an early diagnosis.     

MRI demonstration of arachnoiditis in cauda equina syndrome of ankylosing spondylitis

The cauda equina syndrome is a rare but well-recognised complication of longstanding ankylosing spondylitis, usually presenting when the joint disease is quiescent. The clinical and radiological findings in a patient with only a 3-year history, in whom the onset of joint and neurological symptoms was apparently simultaneous, are presented. MRI revealed characteristic expansion of the lumbar spinal canal with scalloping of the pedicles, laminae and spinous processes, related to numerous posterior dural diverticula. The quantity and extent of such diverticula are unusual. We demonstrated adherence of individual nerve roots to the arachnoid surface of these diverticula and to each other. In a second patient, with a much longer history of both ankylosing spondylitis and cauda equina syndrome, MRI again showed florid, multilocular dural ectasia, marked irregularity and thickening of nerves, and adherence to the dural diverticula. These cases provide evidence for the role of arachnoiditis in the pathogenesis of the cauda equina syndrome of ankylosing spondylitis.     

Cauda equina syndrome and dural ectasia: rare manifestations in chronic ankylosing spondylitis

Cauda equina syndrome (CES) is a rare manifestation in patients with long-standing ankylosing spondylitis (AS). We report a 57-year-old male patient with a 30-year history of AS who developed CES in the past 4 years. The CT and MRI examinations showed unique appearances of dural ectasia, multiple dorsal dural diverticula, erosion of the vertebral posterior elements, tethering of the conus medullaris to the dorsal aspect of the spinal canal and adhesion of the nerve roots of the cauda equina to the wall of the dural sac. A large dural defect was found at surgery. De-adhesion of the tethered conus medullaris was performed but without significant clinical improvement. The possible aetiologies of CES and dural ectasia in patients with chronic AS are discussed and the literature is reviewed.     

Fractures of the thoracolumbar spine in ankylosing spondylitis.

Fractures through the disc or juxta-end plate region of the vertebra as well as the posterior elements have been observed in the thoracic and lumbar spine in ankylosing spondylitis. These are usually associated with increasing pain, usually do not produce neurologic deficit, and may require orthopedic fixation to heal. Irregularity and sclerosis at the margins secondary to pseudarthrosis may develop and should not be confused with a pyogenic or granulomatous infection. Biomechanically these fractures resemble the "seat belt type" or Chance fracture probably because of shifting of the axis of flexion and extension in the ankylosed spine away from its normal location in the center of the nucleus pulposus.     

Cerebral magnetic resonance imaging in a patient with ankylosing spondylitis and multiple sclerosis-like syndrome

Clinical and cerebral magnetic resonance imaging (MRI) findings in a patient with ankylosing spondylitis (AS) and multiple sclerosis-like (MS-like) syndrome are reported. Cerebral MRI demonstrated multiple, MS-like, scattered foci of signal abnormality, one of which showed contrast enhancement. Lesion dissemination in "space and time" is a hallmark for diagnosis of MS, and its demonstration by enhanced cerebral MRI prompted suspicion of coexistence of MS and AS in our patient.     

强直性脊柱炎的影像学诊断研究进展

强直性脊柱炎(ankylosingspondylitis,AS)至今病因不明,缺乏特异的实验室指标,放射学检查是重要诊断方法之一。本文综述了近年来各种影像手段在AS不同病程中的表现和临床应用;并着重介绍X线、MRI的AS分级     

Cervical fracture in ankylosing spondylitis: value of multidimensional imaging.

Ankylosing spondylitis creates a rigid spinal column that cannot easily accommodate to altered or increased forces. Fractures or fracture-subluxation may be seen following apparently trivial injury. Assessment of the lower cervical and cervicothoracic spine can be limited in the kyphotic, ankylosed spine. However, reformatted computed tomography (CT) data can be manipulated to provide true orthogonal (sagittal, coronal) planar images of the obliqued spine, and can be used to provide a three-dimensional overview of anatomy prior to treatment. One such case is presented.