Ankylosing Spondylitis

Diagnosis and Management

Barend J. van Royen, Ben A. C. Dijkmans, Barend J. van Royen, Ben A. C. Dijkmans

• Publisher: CRC Press
• Year: 2006
• ISBN:
  9781000611793
• Edition: 1
• Topic: Medicine
• Subtopic: Medical Theory, Practice & Reference

The first and only interdisciplinary guide dedicated to the subject, this reference leads readers through the pathogenic, genetic, clinical, and biomechanical aspects of ankylosing spondylitis (AS) and addresses issues related to outcomes assessment, medical treatment, surgical complications, disease management, and genetics.

PART I: CLINICAL ESSENTIALS

1
The History of Ankylosing Spondylitis

Jan Dequeker and Kurt de Vlam

Department of Rheumatology, University Hospital K.U.Leuven, Leuven, Belgium

INTRODUCTION

The antiquity of ankylosing spondylitis (AS) is controversial because early descriptions of ancient remains did not clearly differentiate between ankylosing skeletal diseases affecting the axial and peripheral joints (1).

It is now well recognized that on the one hand there are a number of chronic inflammatory rheumatic diseases, which may result in ankylosis of multiple spine and peripheral joints, but clinically they can be differentiated in separate entities. They are usually grouped under the name seronegative spondylarthropathies. Most of these entities affect young adults and are strongly associated with a genetic predisposition identifiable by the antigen HLA-B27. In this group sacroiliac joints and spinal joints are affected.

On the other hand, ankylosis of the spine can also be the result of noninflammatory chronic skeletal disorders as primary and secondary hyperostosis vertebralis. Primary hyperostosis is seen mainly in elderly cases and is considered to be a degenerative-metabolic disorder. In this group the sacroiliac joints are not fused. Secondary hyperostosis can be due to fluor- or vitamin A intoxication or to chronic use of retinoids. Ankylosis of a joint can be the result of direct local infection (e.g., toe), trauma, or immobilization. The characteristic of ankylosis due to infection, trauma, or immobilization is that in the majority of these cases only one joint will be involved.

The study of the history of AS has some limitations, which should be recognized. In paleopathology (study of fossil remains), the only evidence of AS consists of alterations in skeletal remains, as fusion of joints, ligamentous calcifications, and erosions. The latter erosions, compared to complete fusion, can be biased and must be differentiated from other inflammatory diseases such as calcium pyrophosphate dihydrate (CPPD) deposition disease or rheumatoid arthritis (RA). Moreover, after a hundred or even a thousand million years, corrosion and chemical interactions with soil may create artifacts, which have to be interpreted carefully in order to eliminate any bias.

In historical images (paintings, drawings, and etches), general clinical appearance can give additional information for the historian. In longstanding AS, the entire spine is stiff, the lumbar lordosis is flattened, and there is a smoothly curved thoracic kyphosis. In Pott’s disease (tuberculosis of the spine), there is an angular curve.

SKELETAL PALEOPATHOLOGY

The commonly observed osseous alterations of spondylosis deformans and AS have been described in both humans and animals, dating back to prehistoric times. Rogers et al. (1) reviewed the available literature and concluded that many paleopathological specimens, previously reported as AS, are examples of diffuse idiopathic skeletal hyperostosis (DISH) or other seronegative spondylarthropathies. So the antiquity and paleopathology of AS need reappraisal.

The differential diagnosis of ankylosis of the axial skeleton, spine and pelvis in skeletal remains should include AS, DISH, fluorosis, hypervitamin A, and inflammatory spondylarthropathies associated with related rheumatic disorders as juvenile onset chronic arthritis, reactive arthritis, and psoriatic arthritis.

Paleopathology in Animals

Rotschild et al. (2) identified erosive arthritis of the spondylarthropathy variety in the Paleocene of North America 40 million years ago. In 7 out of 37 fossils of the Eocene examined (19%), sacroiliac fusion was noted.

Rotschild and Wood (3) assessed for evidence of spondylarthropathy in 1699 nonhuman Old World primates from 10 different collections. Syndesmophytes and sacroiliac erosions or fusion was present in 2.1% of Old World primates, in 3.2% of lesser apes, and in 6.7% of the great apes (but none of the orangutans was affected).

A detailed description of the pathologic findings of a case of spontaneous AS in an 18.5-year-old Rhesus monkey, compared with another monkey, diagnosed postmortem as hyperostotic spondylosis, is given by Sokoloff et al. (4).

In a radiological study of 48 saber-toothed cat vertebral specimens, Bjorkengren et al. (5) found changes typical of AS in 11 specimens and changes resembling those of DISH in nine specimens. The saber-toothed cat species existed during most of the Pleistocene epoch and became extinct approximately 12,000 years ago. This carnivore was of comparable size but of much heavier build compared to the modern day African lion.

The existence of disease of the spine has been described in two crocodiles, one from Egypt and one from Cuba, dating from the Miocene and Pliocene periods, respectively (6,7,8). Whether these lesions are developmental or pathological, or whether they have any relation to human AS is impossible to judge.

It is well known that in many domestic animals, including dogs, cats, sheep, bulls, cows, pigs, and horses, the incidence of osteophytic outgrowths increases with the age of the animal and is thought to be secondary to degenerative changes in the annulus fibrosus of the intervertebral disc. Thus it is not surprising that similar lesions were present in the mummies of the sacred animals in ancient Egypt (6).

Paleopathology in Humans

Short (9), reviewing the paleopathological literature on RA, concluded that AS, with or without peripheral joint involvement, existed with some frequency in the ancient world but not what we see today as RA. A description of a Stone Age skeleton with complete ankylosis of the lumbosacral and sacroiliac joints is indisputable evidence for the existence of AS in ancient remains (10). Findings on Egyptian mummies concerning arthritis and in particular AS have been criticized (1). Most of the cases found in mummies represent more likely hyperostosis vertebralis, also called DISH, which can cause fusion of the upper third of the sacroiliac joints.

Many Egyptian skeletons, ranging from 3000 B.C. to the beginning of the Christian era, were examined by Ruffer and Rietti and others (7,8,11,12). They described “AS” or “spondylitis deformans” in many cases, but the terms are not clearly defined. Sacroiliac changes were often ignored or absent, and the spinal changes described included asymmetrical fusion with “roughness of bones” elsewhere. Nubian skeletons examined by Smith and Wood Jones (13) were also said to show frequent spinal fusion. Salib describes frequent “spondylitis” and spinal “arthritis deformans” in Egyptian material and Shore states that spinal fusion was seen in 7 of 274 vertebral columns from Ancient Egypt, although he concluded that infection was the most likely cause (12,14). Bourke (15) also looked at Egyptian and Nubian material and reported some possible cases ofAS. However, only one case, an individual from Hou, is convincing (Fig. 1), and in others the asymmetrical changes with large paravertebral osteophytosis suggest possible DISH or psoriatic arthritis. Zorab (16) was unable to find convincing evidence of AS in Egyptian material and thought that the previous authors had misdiagnosed osteophytosis.

Two examples of peripheral joint disease and cervical spine ankylosis were found in the tomb of the third Dynasty (2700 B.C.). The first bony specimens involved the distal joint of one finger, with bony ankylosis in a flexed position. An accompanying fragment demonstrates two cervical vertebrae firmly joined by anterior and posterior paravertebral calcification (11). The other is an ankylosed knee, with patella fused to the femur. In this subject, definite cervical spondylitis is pictured, with bony bridging (9). Ruffer (12) describes a possible case of AS: a third dynasty (2980–2900 B.C.) Egyptian named Nefermaat. This unfortunate patient has bony ankylosis of his apophyseal joints, along with bone formation in his long ligaments. His spine is a solid block from the fourth cervical vertebra to the coccyx. According to a recent publication by Feldtkeller et al. (17) reviewing the published material about the remains of the pharaohs of ancient Egypt’s 18th and 19th dynasty, at least three had AS: Amenhotep (Amenophis) II, Ramses II (“The Great”) and his son Mezenptah.

Rogers et al. (1) concluded that there are surprisingly few convincing descriptions of human AS in other paleopathological literature. A possible French case from the Neolithic period was described by Snorrason (18). Morse (19) and Kidd (20) have both examined suspected cases from ancient midwestern skeletons; Zivanovic (21) records a case of medieval Anglo-Saxon origin with probable AS (although he diagnosed RA); and Kramar (22) gave a detailed description of a very convincing case from medieval Geneva. calv...