Andersson Lesion Research Articles

Discovertebral (Andersson) lesions in severe ankylosing spondylitis: a study using MRI and conventional radiography

The objective of this study is to investigate the prevalence of Andersson lesions (AL) in ankylosing spondylitis (AS) patients who will start anti-tumor necrosis factor (TNF) treatment. Radiographs and magnetic resonance imaging (MRI) of the spine were performed before therapy with anti-TNF. ALs were defined as discovertebral endplate destructions on MRI, associated with bone marrow edema and fat replacement or sclerosis, a decreased signal on T1, enhancement after contrast administration (gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA)), and increased signal on T2 and short tau inversion recovery (STIR). Additionally, conventional radiography showed a fracture line, irregular endplates, and increased sclerosis of adjacent vertebral bodies. Fifty-six AS patients were included, 68% males, mean age of 43 years, and mean disease duration of 11 years. The mean bath ankylosing spondylitis disease activity index was 6.4, and 24% of all patients had ankylosis. Only one patient showed a discovertebral abnormality with bone marrow edema of more than 50% of the vertebral bodies adjacent to the intervertebral disk of T7/T8 and T9/T10, a hypodense signal area on T1, and a high signal on STIR. Irregular endplates were depicted, and T1 after Gd-DTPA demonstrated high signal intensity around the disk margins. However, no fracture line was visible on conventional radiology, and therefore, this case was not considered to be an AL. No AL was detected in our AS patients, who were candidates for anti-TNF treatment. One patient showed a discovertebral abnormality on MRI, without a fracture line on conventional radiology. The relative small proportion of patients with a long-established disease might explain this finding for, particularly, an ankylosed spine is prone to develop an AL.

Polysegmentäre Anderssonläsion bei ankylosierender Spondylitis

Basing on roentgenological observation of the course of the disease, and on postmortem examination, of a patient with polysegmental Andersson lesions (known as spondylodiscitis) in ankylosing spondylitis, the article reports on the histological and often also clinico-roentgenological possibility of differentiating between an inflammatory and non-inflammatory type of this destructive lesion. The non-inflammatory type of Andersson lesion reflects a fracture due to fatigue, or its sequel, eg pseudarthrosis, in the stiffened axial skeleton. In this particular patient, renal osteopathy had favoured the genesis of the disease.

Discovertebral (Andersson) lesions of the spine in ankylosing spondylitis revisited

A well-known complication in patients with ankylosing spondylitis (AS) is the development of localised vertebral or discovertebral lesions of the spine, which was first described by Andersson in 1937. Since then, many different terms are used in literature to refer to these localised lesions of the spine, including the eponym ‘Andersson lesion’ (AL). The use of different terms reflects an ongoing debate on the exact aetiology of the AL. In the current study, we performed an extensive review of the literature in order to align communication on aetiology, diagnosis and management between treating physicians. AL may result from inflammation or (stress-) fractures of the complete ankylosed spine. There is no evidence for an infectious origin. Regardless of the exact aetiology, a final common pathway exists, in which mechanical stresses prevent the lesion from fusion and provoke the development of pseudarthrosis. The diagnosis of AL is established on conventional radiography, but computed tomography and magnetic resonance imaging both provide additional information. There is no indication for a diagnostic biopsy. Surgical instrumentation and fusion is considered the principle management in symptomatic AL that fails to resolve from a conservative treatment. We advise to use the term Andersson lesion for these spinal lesions in patients with AS.

Transpedicular wedge resection osteotomy for the treatment of a kyphotic Andersson lesion-complicating ankylosing spondylitis

Two cases with a long-standing thoracolumbar kyphosis due to ankylosing spondylitis are presented with a symptomatic localized destructive kyphotic lesion of the spine. Clinical and radiographic findings demonstrated a progressive vertebral and discovertebral kyphotic pseudarthrosis, known as an Andersson lesion, at the L1 and L1-2 level, respectively. Surgical correction and stabilization was performed by an extending transpedicular wedge resection osteotomy to restore spinal stability, to facilitate fracture healing as well as to restore the sagittal balance of the ankylosed spine. To predict the effect of a surgical correction of the Andersson lesion on the sagittal balance, deformity planning was performed preoperatively. The indication for surgery, the surgical technique and the 2 years' clinical results are described. In addition, the difficulties experienced with preoperative deformity planning are evaluated.

Spinal Changes in Patients with Spondyloarthritis: Comparison of MR Imaging and Radiographic Appearances

Since the advent of highly effective TNF-alpha inhibitors for treating spondyloarthritides, referring rheumatologists have been requesting the sensitive visualization of inflammatory changes not only of the sacroiliac joints but of the entire spine. Given that changes in spondyloarthritis may be very subtle, their visualization by means of magnetic resonance (MR) imaging relies critically on selecting the proper imaging protocol. Spinal changes associated with spondyloarthritis are florid anterior spondylitis (or Romanus lesion), florid diskitis (or Andersson lesion), ankylosis, insufficiency fractures of the ankylosed spine, syndesmophytes, arthritis of the apophyseal and costovertebral joints, and enthesitis of the interspinal ligaments. A comparison of MR imaging findings with those of conventional radiography in individual patients reveals strengths and weaknesses of both modalities. Results of this comparison suggest that syndesmophytes are depicted better with radiography; ankylosis, equally well with both imaging techniques; and all other lesions, better with MR imaging. Classification of the different findings based on the typical signal-intensity changes seen on MR images enables standardized reporting, and scoring the lesions may be helpful in clinical trials.

Magnetic resonance imaging of the axial skeleton in rheumatoid disease

The axial skeleton is a target for both spondyloarthritis and rheumatoid arthritis. While conventional radiography allows the clear documentation of the late stages of inflammatory changes, magnetic resonance imaging (MRI) is sensitive enough to depict early inflammatory lesions. It is, therefore, of particular importance for radiologists and clinicians to know the MRI appearances of inflammatory changes of the axial skeleton in rheumatoid diseases. Typical lesions in ankylosing spondylitis and related conditions comprise spondylitis (Romanus lesion), spondylodiscitis (Andersson lesion), arthritis of the apophyseal joints, the costovertebral and costotransverse joints, and insufficiency fractures of the ankylosed vertebral spine (non-inflammatory type of Andersson lesion). Sacroiliitis is associated with chronic changes such as sclerosis, erosions, transarticular bone bridges, periarticular accumulation of fatty tissue and ankylosis. In addition, acute findings include capsulitis, juxta-articular osteitis and the enhancement of the joint space after contrast medium administration. Another important sign of spondyloarthritis is enthesitis, which affects the interspinal and supraspinal ligaments of the vertebral spine and the interosseous ligaments in the retroarticular space of the sacroiliac joints. The main site of manifestation of spinal involvement in rheumatoid arthritis is the cervical spine. Typical changes are the destruction of the atlantoaxial complex by pannus tissue with subsequent atlantoaxial subluxation, basilar impression and erosion of the dens axis. Changes in the lower segments of the cervical spine are destruction of the apophyseal joints resulting in the so-called stepladder phenomenon. Because of the uniform response of the discovertebral complex to different noxae, a number of different conditions must be distinguished on the basis of the patient's clinical findings and history in combination with their imaging appearance. These conditions comprise degenerative disc disease, septic spondylodiscitis, Scheuermann's disease, Paget's disease and diffuse idiopathic skeletal hyperostosis (DISH).

Discovertebral lesion in ankylosing spondylitis: differential diagnosis with discitis by magnetic resonance imaging

Ankylosing spondylitis (AS) is occasionally accompanied by erosive changes in the vertebral endplate at one or more restricted levels (Andersson lesions). The radiographic findings of this lesion are similar to those of bacterial discitis, and a differential diagnosis between them is often difficult. These diseases must be diagnosed correctly because they require different treatments. In order to evaluate the prevalence of Andersson lesions in the Japanese population, we examined 31 cases of AS which were treated in our department, and Andersson lesions were found in three (9.7%) of them. All these three cases developed Andersson lesions in the earlier phase of the AS, and differentiating the lesions from bacterial discitis was difficult. The details of these three cases are reviewed, and the importance of differentiating between Andersson lesions and bacterial discitis is discussed. Plain radiographs showed no clear difference between these conditions, but magnetic resonance imaging (MRI) was found to be more efficient.

Spondylodiscitis in ankylosing spondylitis, inflammation or trauma? A description of six cases.

An uncommon, but well recognised complication of Ankylosing Spondylitis (AS) is spondylodiscitis, a destructive discovertebral lesion also called the Andersson lesion. We describe six cases, with variable clinical presentation and radiological appearance. Two had multiple lesions, in one patient spondylodiscitis was the presenting symptom of AS. None had a history of even a minor trauma. Prognosis was good with conservative treatment including NSAID's, rest, and physiotherapy. In two cases histopathology was studied and suggested sterile inflammation as the main etiologic factor. The literature is reviewed regarding the mechanisms that may contribute to these lesions: mainly inflammatory like increasing enthesopathy or mainly mechanical like pseudoarthrosis about a fracture site. It may be that both mechanisms can result in similar destructive intervertebral disc lesions.

A destructive discovertebral lesion: Septic discitis, ankylosing spondylitis, or rheumatoid arthritis ?

A 41-year-old male with a 20-year history of classical ankylosing spondylitis, psoriasis and seropositive, nodular erosive rheumatoid arthritis presented with a 12-month history of thoracolumbar junction pain following minor trauma. A pseudoarthrosis was noted at the T11/12 level on plain radiographs and tomograms. A gallium scan showed no increased isotope uptake, and a computed tomogram (CT) revealed no evidence of a paraspinal collection. Conservative management including cast immobilisation and local radiotherapy was ineffective, and spinal fusion was required. A typical Andersson lesion was found at operation. The diagnostic and therapeutic problems of such discovertebral lesions are discussed.

Current radiodiagnostic concept of ankylosing spondylitis.

Nine radiodiagnostic rules are drawn from the X-rays of 2125 ankylosing spondylitis patients. The significance of early diagnosis of the 'multicolored' saroiliac X-ray is looked onto; the syndesmophyte, squaring-phenomenon, barrel-shaped vertebra, Romanus and Andersson lesions, and the ossification of ligaments are discussed. The changes at the apophyseal and the costovertebral joints, unimportant for early diagnosis, are explored.

Disco-vertebral destructive lesions (So-called Andersson Lesions) associated with ankylosing spondylitis

Radiological examination of 31 patients with established ankylosing spondylitis revealed 58 disco-vertebral destructive lesions. Careful assessment of their radiological features permitted differentiation into two main types, (1) inflammatory and (2) non-inflammatory. The ‘inflammatory’ type may represent either an active inflammatory process or a late sequel to such a lesion. In this series 44 lesions were included in this category, with a marked predilection for the lumbar spine. Moreover, all were observed within the first decade following the onset of the disease.