Imaging Characteristics of Diffuse Idiopathic Skeletal Hyperostosis With an Emphasis on Acute Spinal Fractures: Review

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1 Imaging Characteristics of Diffuse Idiopathic Skeletal Hyperostosis With an Emphasis on cute Spinal Fractures: Review Mihra S. Taljanovic 1, Tim. Hunter 1, Ronald J. Wisneski 2, Joachim F. Seeger 1, Christopher J. Friend 3, Stephanie. Schwartz 1, Lee F. Rogers 1 JR Integrative Imaging LIFELONG LERNING FOR RDIOLOGY Objective The educational objectives of this self-assessment module are for the participant to exercise, self-assess, and improve his or her understanding of the imaging of diffuse idiopathic skeletal hyperostosis (DISH), with emphasis on acute spinal fractures. Conclusion Understanding the pathomechanics of the fractures in the ankylosed spine is important in the differentiation of the acute spinal fractures in DISH and ankylosing spondylitis. This article emphasizes the imaging features of spinal DISH and acute spinal fractures in DISH, distinguishing them specifically from those in ankylosing spondylitis. Introduction DISH [1], often referred to as Forestier disease [2], is a common disorder of unknown cause characterized by intermittent pain and stiffness in areas of bony changes of the spine. The incidence of DISH has been reported to be seven in every 100 men and four in every 100 women older than 30 years [3]. This disorder produces characteristic spinal or extraspinal manifestations [2]. Spinal DISH is typically characterized by the presence of flowing ossification of variable thickness (up to 2 cm) along the anterolateral margins of at least four contiguous vertebral bodies [2 4] (Fig. 1). The main differential diagnosis of spinal DISH includes spondylosis deformans, ankylosing spondylitis, reactive arthritis, and psoriatic arthritis [2]. Fusion of the facet joints, costovertebral joints, and sacroiliac joints, which are characteristic of ankylosing spondylitis, are not seen in DISH [2]. Pathologic features of spinal DISH include focal and diffuse calcification and ossification of the anterior longitudinal ligament, paraspinal connective tissue, and annulus fibrosis; degeneration in the peripheral annulus fibrosis fibers; anterolateral extensions of fibrous tissue; hypervascularity; chronic inflammatory cellular infiltration; and periosteal new bone formation on the anterior surface of the vertebral bodies [5]. cute spinal fractures associated with DISH are not common but can lead to serious complications, including nonunion, deformity, neurologic injury, and death [3, 6]. cute spinal fractures that occur in DISH may be mistaken for or misinterpreted as those of ankylosing spondylitis. Different patterns of spinal fractures in patients with DISH and in those with ankylosing spondylitis can be explained by differences in the pathomechanics of these diseases [3]. Clinical Manifestations of Spinal DISH Clinical symptoms in spinal DISH are usually mild and include spinal stiffness and mild intermittent and nonradiating thoracolumbar pain that becomes evident in middle age. Generally, no significant change occurs in normal spinal mechanics, and the clinical findings are usually mild in comparison with the extent of the radiographic abnormalities. With progression of the disease, pain and stiffness may involve the lumbar and cervical segments [2]. Occasionally, patients with DISH may have severe limitation of spinal mobility and associated postural abnormality as is seen with advanced ankylosing spondylitis [7]. Prominent flowing ossifications of DISH in the cervical spine can cause dysphagia [2, 4, 8]. However, many patients with DISH are asymptomatic and their disease is discovered incidentally [4]. The association of ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum with DISH may explain, in part, the occasional presence of neurologic findings in patients with DISH [2, 9]. Sharma et al. [10] showed in retrospective analysis that 15% of patients with DISH presenting to a particular neurosurgical unit had serious neurologic manifestations requiring neurosurgical intervention. Keywords: acute fracture, diffuse idiopathic skeletal hyperostosis, spinal fractures DOI: /JR Received June 3, 2008; accepted after revision October 7, Department of Radiology, The University of rizona Health Sciences Center, 1501 N Campbell ve., Tucson, Z ddress correspondence to M. S. Taljanovic (mihrat@radiology.arizona.edu). 2 Department of Orthopaedic Surgery, The University of rizona Health Sciences Center, Tucson, Z. 3 Inland Imaging Z, Gilbert, Z. JR 2009;193:S10 S X/09/1933 S10 merican Roentgen Ray Society S10 JR:193, September 2009

2 Diffuse Idiopathic Skeletal Hyperostosis Fig year-old man with diffuse idiopathic skeletal hyperostosis. and, nteroposterior () and lateral () radiographs of thoracic spine show characteristic flowing ossifications at anterolateral aspect of multiple contiguous levels on right side. Imaging Characteristics of Spinal DISH The diagnosis of DISH in most patients is made with radiography and, if needed, further characterization may be provided by cross-sectional imaging, including CT and MRI. CT and MRI are useful in the evaluation of trauma and in the rare cases of spinal stenosis in patients with DISH that are caused by ossification of spinal ligaments or hypertrophy of the apophyseal joints [2]. Three strict radiographic findings in the spine serve as a prerequisite for the diagnosis of DISH. First, flowing calcification and ossification along the anterolateral aspect of at least four contiguous vertebral bodies with or without associated localized pointed excrescences at the intervening vertebral body intervertebral disk junctions separate this condition from typical spondylosis deformans (Figs. 1 and 2). Second, relative preservation of the intervertebral disk height in the involved vertebral segment and the absence of extensive radiographic changes of degenerative disk disease, including vacuum phenomena and vertebral body marginal sclerosis, distinguishes DISH from intervertebral (osteo)chondrosis. Last, the absence of apophyseal joint ankylosis and costovertebral joint fusion (Fig. 3), as well as the absence of sacroiliac joint erosions, sclerosis, or intraarticular osseous fusion in the synovial portion of these joints, differentiates this entity from ankylosing spondylitis [2]. However, in DISH, asymmetric intraarticular osseous fusion may occur in the proximal fibrous portion of the sacroiliac joints [2]. Osteoporosis is not a feature of DISH [2]. ssociation of DISH and OPLL, which is most commonly encountered in the cervical spine, is common and may be noted in up to 50% of the patients with DISH. Ossification of the ligamentum flavum is commonly associated with DISH [2, 9, 11, 12]. DISH in the Thoracic Spine The thoracic spine is most commonly involved, particularly T7 T11 [4] (Fig. 1). nkylosis is more commonly seen in the thoracic than in the cervical or lumbar spine. nkylosis is frequently incomplete, with interdigitating areas of protruding disk material in the flowing ossifications [2] (Fig. 4). CT parallels the radiographic findings. The superb spatial resolution of CT allows accurate assessment of the facet joints, which is important in the differentiation of DISH and ankylosing spondylitis (Fig. 3). In the thoracic spine involved by DISH, bridging ossifications are commonly seen along the right lateral aspect of the thoracic spine [4] and not on the left lateral aspect, probably related to an inhibiting effect on ossification by pulsation of the descending thoracic aorta (Figs. 1 and 2). Patients with situs inversus develop flowing ossifications on the left side [2, 4]. JR:193, September 2009 S11

3 Taljanovic et al. Fig year-old woman with spondylosis deformans. and, nteroposterior () and lateral () radiographs of thoracic spine show disk space narrowing and marginal endplate osteophytes at multiple levels without bridging ossifications. Fig. 3 bsence of apophyseal joint ankylosis and costovertebral joint fusion with diffuse idiopathic skeletal hyperostosis, which is present with ankylosing spondylitis., xial CT image of thoracic spine in 66-year-old man with diffuse idiopathic skeletal hyperostosis shows normal apophyseal joints with no evidence of fusion (long arrow) and mild osteoarthritic changes of costovertebral joints that are not fused (short arrow)., xial CT image of thoracic spine in 59-year-old man with ankylosing spondylitis shows fused apophyseal joints (long arrow) and fused costovertebral joints (short arrow). S12 JR:193, September 2009

4 Diffuse Idiopathic Skeletal Hyperostosis Fig year-old man with diffuse idiopathic skeletal hyperostosis. and, nteroposterior () and lateral () radiographs of thoracic spine show interdigitating areas of protruding disk material in flowing ossifications at multiple levels (arrows). Ossifications at the posterior aspect of the thoracic spine are rare [2]. Flowing ossifications produce a bumpy contour of the thoracic spine (Figs. 1 and 2). Under these ossifications, radiolucencies are seen along the anterior aspect of the vertebral bodies (Fig. 5). These radiolucencies end at the level of the vertebral endplates where horizontal struts of new bone deposit are seen. This is related to the anatomy of the anterior longitudinal ligament, which adheres tightly to the vertebra at its central point and less tightly near the endplates [2] (Fig. 5). The anterior extension of disk material produces additional radiolucencies in the bridging ossifications at the level of disk spaces of various shapes (L-, T-, and Y-shaped) (Fig. 4). There is usually no significant thoracic disk space narrowing. Intervertebral disk calcifications may occur [2] (Fig. 6). Ossifications about and between the spinous processes may be seen [2, 4] (Fig. 6). Thoracic spine DISH may be accompanied by cortical thickening and hyperostosis of the posterior aspect of the ribs [2, 4]. However, the apophyseal joints and costovertebral joints are spared and not fused in DISH. DISH in the Cervical Spine Involvement of the cervical and lumbar spine with DISH is common. Lower cervical segments are more commonly involved. Progressive bone depositions along the vertebral bodies extend over the disk spaces and form either smooth or bumpy flowing ossification [2, 4]. Radiolucent areas along the anterior aspect of the cervical vertebral bodies are less frequent than in the thoracic spine [2]. Radiolucent disk extension may be observed in the cervical spine, which may isolate a small triangular ossicle in front of the disk space [2] (Fig. 7). Degenerative changes of the cervical apophyseal joints, ossifications of the nuchal ligament, posterior spinal osteophytes, and calcification or ossification of the posterior longitudinal ligament may be seen. Hyperostosis about the atlantoaxial joint and hyperostosis at the occiput can occur [2]. Fig year-old man with diffuse idiopathic skeletal hyperostosis. and, Lateral radiographs of thoracic spine show radiolucencies at anterior aspect of thoracic vertebral bodies subjacent to flowing ossifications (arrowheads). These radiolucencies end at level of vertebral endplates, where horizontal struts of new bone deposit are seen (arrows). JR:193, September 2009 S13

5 Taljanovic et al. DISH in the Lumbar Spine The upper lumbar segments are more commonly involved. The radiographic abnormalities along the anterior aspect of the lumbar spine are similar to those in the cervical spine [2, 4]. Unlike the thoracic spine, flowing ossifications are equally frequent on the right and left sides of the lumbar spine [2]. Ossifications about the spinous processes and interspinous ligaments may be observed [2]. Degenerative disk space narrowing is typically mild to moderate. Degenerative changes of the apophyseal joints may occur in the lower lumbar spine and at the lumbosacral junction, but no fusion is seen [2, 4]. DISH in the Sacrum and Sacroiliac Joints ridging ossifications are observed about the anterior articular margins of the sacroiliac joints, resulting in paraar- C Fig year-old man with diffuse idiopathic skeletal hyperostosis (DISH). and, Coronal () and sagittal () reformatted CT images of thoracic spine show transverse fracture through inferior aspect of T8 vertebral body (arrows) extending () into mid portion of subjacent T8 T9 disk space (arrowhead, ). C, nteroposterior radiograph of thoracic spine shows thoracolumbosacral orthotic brace in place. Mechanism of injury was hyperextension. Note intervertebral disk calcifications at multiple levels and ossification of interspinous ligaments as seen in. D, xial CT image shows apophyseal joints were not fused, which distinguishes DISH from ankylosing spondylitis (arrows). D S14 JR:193, September 2009

6 Diffuse Idiopathic Skeletal Hyperostosis Fig. 7 Sagittal reformatted CT image of cervical spine in 73-year-old woman with diffuse idiopathic skeletal hyperostosis shows radiolucent disk extension (arrow) that isolates small triangular ossicle in front of disk space. 7 8 Fig. 8 xial CT scan shows bridging ossifications at anterior aspect of sacroiliac joints in 81-year-old man with diffuse idiopathic skeletal hyperostosis (arrows). ticular fusion [2, 4, 13] (Fig. 8). symmetric intraarticular fusion, when it occurs, predominates in the proximal fibrous portion of the sacroiliac joints [2]. Pathomechanics of cute Spinal Fractures in nkylosed Spine The ankylosed spine is more prone to fracture than a normal spine, which has been reported in both DISH and ankylosing spondylitis. These fractures can occur after even minor trauma [2, 14]. Spinal fractures in ankylosing spondylitis are more common than those in DISH, probably because of osteoporosis associated with ankylosing spondylitis [14 16]. Fractures in DISH typically occur in patients with moderate to severe disease in which osseous fusion of the long spinal segments is present [2]. DISH produces exuberant, broad, and irregular bridging ossification, which encompasses the annulus fibrosis, anterior longitudinal ligament, and paraspinal connective tissue, with an anterior distribution. The bridging ossifications are thickest at the level of the disk space and attach to the adjacent vertebral bodies. road areas of the proximal and distal thirds of the vertebral bodies are covered by the ossifications, leaving the sites above and below their attachment with the least amount of hyperostosis [3]. Taking into consideration the pattern of ossification in DISH and the relative preservation of the disk space, it is logical to expect fractures to occur in the regions of least resistance, such as through the mid vertebral body above or below the attachment sites of flowing ossifications [2]. nother type of spinal fracture in patients with DISH involves the end of an ankylosed segment causing disruption of the disk space. These fractures occur at the level of the stress risers at the junction of the mobile and fused spine [3]. In contrast, the thin vertical syndesmophytes of ankylosing spondylitis form at the outer fibers of annulus fibrosis and bridge the adjacent vertebrae. Chondroid metaplasia, calcifications, and ossifications progress through and weaken the involved disk over time [3]. In the early stages of Fig year-old man with diffuse idiopathic skeletal hyperostosis. and, Coronal () and sagittal () reformatted CT images of thoracic spine show fracture involving superior endplate of T7 vertebral body on left and involvement and mild widening of T6 T7 disk space. This widening is consistent with anterior and posterior longitudinal ligamentous injury (arrows). Mechanism of injury was hyperextension. JR:193, September 2009 S15

7 Taljanovic et al. Fig year-old man with diffuse idiopathic skeletal hyperostosis. C, Sagittal reformatted CT image () and sagittal T1-weighted () and T2-weighted fat-suppressed (C) MR images of thoracic spine show transverse fracture of T7 vertebra that involves central aspect of vertebral body and posterior elements (arrow). Fracture line is hypointense on T1-weighted () and hyperintense on T2-weighted fat-suppressed (C) MR images. D, On coronal reformatted CT image, note active extravasation of contrast material (arrow) in right paraspinal region at fracture site from injured intercostal artery. Mechanism of injury was translation shear. E, Sagittal CT reformatted image of lumbar spine shows additional compression fracture of superior endplate of L1 vertebral body (arrow). Mechanism of injury was flexion compression. C D E ankylosing spondylitis, most fractures occur through the disk space. In late disease, osteopenia coupled with ossification of the entire disk can render the vertebral body the weak point, and fracture may occur through the vertebral body rather than the disk space [3]. cute Spinal Fractures in DISH Different patterns of spinal fractures in patients with DISH and in those with ankylosing spondylitis can be explained by differences of these two diseases and the pathomechanics of the ankylosed spine [3]. Fractures usually occur with advanced DISH because the ankylosed segments are prone to fracture, even with relatively minor trauma [2, 4, 16 18]. They are more common in the thoracic and cervical spine than in the lumbar region [2]. Hyperextension is the most common mechanism of injury [2, 4, 6] (Figs. 6 and 9), but other mechanisms of injury may occur (Figs ). Odontoid fractures [3] and atlantoaxial instability [19] have been reported. Facet joint fracture or dislocation has also been reported in the cervical spine [10] (Fig. 11). fter evaluating 14 cervical spine fractures, one thoracic spine fracture, and one lumbar spine fracture in 16 patients with spinal DISH, Hendrix et al. [16] proposed that patients with longer ankylosed segments will have more severe spinal cord injury than those with shorter ankylosed segments. Fractures in DISH may involve the vertebral body in the ankylosed segment or may occur close to the endplate, with associated disruption of the intervertebral disk (Figs. 6, 9, and 10), but they can also occur through the intervertebral disk [16] (Fig. 11). Most spinal fractures in ankylosing spondylitis are transdiskal [3, 4] (Fig. 13), but they can also occur through the vertebral body, as was recently shown by Wang et al. [14]. Fracture through an ankylosed segment with continued motion at the site of fracture can result in pseudoarthrosis, which can also develop at the junction of the fused and mobile spine secondary to chronic abnormal stresses. This complication manifests radiographically as single-level intervertebral disk space destruction, vertebral endplate erosions, marked vertebral sclerosis, and large osteophytes, and can mimic infective spondylitis or neuropathic changes [20]. In most patients, the diagnosis of acute spinal fractures associated with DISH is made with radiography. Further S16 JR:193, September 2009

8 Diffuse Idiopathic Skeletal Hyperostosis C Fig year-old man with diffuse idiopathic skeletal hyperostosis who presented with quadriplegia after fall. C, Sagittal reformatted CT images of cervical spine show bilateral interfacetal fracture dislocation of cervical spine at C5 C6 level (arrows). D, Posterior spinal fusion was performed at C5 C6 level. Radiograph shows smooth, flowing ossification at anterior aspect of mid and lower cervical spine, which is also seen on CT image (). D characterization may be provided by CT (Figs. 7, 9, and 10) and MRI [4, 21 24] (Fig. 10). MDCT with multiplanar reformatted images has superb spatial resolution and best defines not only the presence of fracture but also the full extent of the osseous injuries [21, 22]. MRI with its superb contrast resolution and multiplanar imaging capabilities enables detailed evaluation of the spinal column, including spinal cord and ligamentous injuries, as well paraspinal ligamentous injuries and soft-tissue hematomas. ecause of the higher prevalence of spinal cord and soft-tissue injuries associated with acute spinal fractures with DISH, MRI plays a fundamental role in the assessment in these patients [21 23]. Posttraumatic intravertebral fluid collections associated with hyperextension injuries have been described in patients with DISH [24]. Treatment of Spinal Fractures in DISH Early stabilization of the fractured spine is needed to preclude nonunion, osteolysis, late instability, and neurologic deficit. Operative stabilization is usually required for significantly JR:193, September 2009 S17

9 Taljanovic et al. Fig year-old man with diffuse idiopathic skeletal hyperostosis. C, Sagittal reformatted CT image () and sagittal T1-weighted () and T2-weighted fat-suppressed (C) MR images of cervical spine show no evidence of fracture. MR images show no evidence of spinal cord injury. Note edema in posterior soft tissues and in region of interspinous ligaments, and mild edema in prevertebral soft tissues at C2 C3 level, consistent with musculoligamentous strain. Note also ossification in posterior longitudinal ligament at C6 C7 level (arrows, and C) and bumpy contour of cervical spine related to flowing ossifications. C Fig year-old man with ankylosing spondylitis (same patient as in Fig. 3). C, Sagittal CT reformatted image () and sagittal T1-weighted () and T2-weighted fat-suppressed (C) MR images of thoracic spine show transdiskal fracture at T8 T9 level that extends into subjacent superior endplate (arrow). On MR images, note bone marrow edema about inferior endplate of T8 and superior endplate of T9. (Fig. 13 continues on the next page) C S18 JR:193, September 2009

10 Diffuse Idiopathic Skeletal Hyperostosis displaced or unstable fractures (Fig. 11D). Nonoperative treatment with bed rest, orthotic devices, or halo vest can be used for more stable, minimally displaced fractures or as an adjunct to operative treatment [3, 4] (Fig. 6C). Conclusion Spinal DISH is a common bone-forming disorder in the middle-aged and elderly population. Patients with advanced DISH may sustain acute spinal fractures even after minor trauma. cute fractures in patients with DISH frequently occur in a typical pattern. Different patterns of spinal fractures in patients with DISH, and in those with ankylosing spondylitis, can be explained by differences in the pathogenesis and pathomechanics of these two diseases. D Fig. 13 (continued) 59- year-old man with ankylosing spondylitis (same patient as in Fig. 3). D, cute fracture was stabilized with posterior spinal fusion. References 1. Resnick D, Shaul SR, Robins JM. Diffuse idiopathic skeletal hyperostosis (DISH): Forestier s disease with extraspinal manifestations. Radiology 1975; 115: Resnick D. Diffuse idiopathic skeletal hyperostosis. In: Resnick D, ed. Diagnosis of bone and joint disorders, 4th ed. Philadelphia, P: Saunders, 2002: Paley D, Schwartz M, Cooper P, Harris WR, Levine M. Fractures of the spine in diffuse idiopathic skeletal hyperostosis. Clin Orthop Relat Res 1991; 267: elanger T, Rowe DE. Diffuse idiopathic skeletal hyperostosis: musculoskeletal manifestations. J m cad Orthop Surg 2001; 9: Resnick D, Niwayama G. Radiographic and pathologic features of spinal involvement in diffuse idiopathic skeletal hyperostosis (DISH). Radiology 1976; 119: Sreedharan S, Li YH. Diffuse idiopathic skeletal hyperostosis with cervical spinal cord injury: a report of 3 cases and a literature review. nn cad Med Singapore 2005; 34: Olivieri I, D ngelo S, Cutro MS, et al. Diffuse idiopathic skeletal hyperostosis may give the typical postural abnormalities of advanced ankylosing spondylitis. Rheumatology (Oxford) 2007; 46: ; Epub 2007 Oct Giger R, Dulguerov P, Payer M. nterior cervical osteophytes causing dysphagia and dyspnea: an uncommon entity revisited. Dysphagia 2006; 21: Hukuda S, Mochizuki T, Ogata M, Shichikawa K. The pattern of spinal and extraspinal hyperostosis in patients with ossification of the posterior longitudinal ligament and the ligamentum flavum causing myelopathy. Skeletal Radiol 1983; 10: Sharma RR, Mahapatra, Pawar SJ, Sousa J, Lad SD, thale SD. Spinal cord and cauda equina compression in DISH. Neurol India 2001; 49: Ehara S, Shimamura T, Nakamura R, Yamazaki K. Paravertebral ligamentous ossification: DISH, OPLL and OLF. Eur J Radiol 1998; 27: Resnick D, Guerra J Jr, Robinson C, Vint VC. ssociation of diffuse idiopathic skeletal hyperostosis (DISH) and calcification and ossification of the posterior longitudinal ligament. JR 1978; 131: Dar G, Peleg S, Masharawi Y, Steinberg N, Rothschild M, Hershkovitz I. The association of sacroiliac joint bridging with other enthesopathies in the human body. Spine 2007; 32:E303 E Wang YF, Teng MM, Chang CY, Wu HT, Wang ST. Imaging manifestations of spinal fractures in ankylosing spondylitis. JNR 2005; 26: Hunter T, Forster, Dvorak M. nkylosed spines are prone to fracture. Can Fam Physician 1995; 41: Hendrix RW, Melany M, Miller F, Rogers LF. Fracture of the spine in patients with ankylosis due to diffuse skeletal hyperostosis: clinical and imaging findings. JR 1994; 162: Callahan EP, guillera H. Complications following minor trauma in a patient with diffuse idiopathic skeletal hyperostosis. nn Emerg Med 1993; 22: de Peretti F, Sane JC, Dran G, Razafindratsiva C, rgenson C. nkylosed spine fractures with spondylitis or diffuse idiopathic skeletal hyperostosis: diagnosis and complications [in French]. Rev Chir Orthop Repar ppar Mot 2004; 90: Chiba H, nnen S, Shimada T, Imura S. tlantoaxial subluxation complicated by diffuse idiopathic skeletal hyperostosis: a case report. Spine 1992; 17: Quagliano PV, Hayes CW, Palmer WE. Vertebral pseudoarthrosis associated with diffuse idiopathic skeletal hyperostosis. Skeletal Radiol 1994; 23: Gonzalez-eicos, Nuñez D Jr, Fung W, Sanchez M, Gahbauer H. Trauma to the ankylotic spine: imaging spectrum of vertebral and soft tissue injuries. Emerg Radiol 2007; 14: ; Epub 2007 Sep Rao SK, Wasyliw C, Nunez D Jr. Spectrum of imaging findings in hyperextension injuries of the neck. RadioGraphics 2005; 25: Strohm PC, Zwingmann J, ley T, Köstler W, Südkamp NP. Injuries of the cervical spine with Forestier s disease: problems in the diagnostic and surgical management [in German]. Unfallchirurg 2006; 109: Le Hir PX, Sautet, Le Gars L, et al. Hyperextension vertebral body fractures in diffuse idiopathic skeletal hyperostosis: a cause of intravertebral fluidlike collections on MR imaging. JR 1999; 173: FOR YOUR INFORMTION The reader s attention is directed to the Self-ssessment Module for this article, which appears on the following pages. JR:193, September 2009 S19