Radiologic-Pathologic Correlations of the Vertebral Column Component of Ankylosing Spondylitis 2009 2 Elective Student P. H.
Case 63 year old man Chief complaint Tingling sensation of left leg Gait disturbance Instability while descending stairs History of Presenting Illness Symptoms began 2 years ago Presented to local doctor whom then referred on to Jikei orthopedic outpatient
Examination Sensory disturbance of posterolateral aspect of the left leg Left gastrocnemius muscle atrophied Left ankle reflex absent Heel gait normal Toe gait and hopping not possible
Investigations Ankle brachial index (ABI) & Cardio-ankle vascular index (CAVI) both normal Plain film studies of the lumbar spine taken
Diagnosis and Management Ankylosing Spondylitis Patient was subsequently lost to follow up
Definition of Ankylosing Spondylitis Chronic inflammatory disorder principally involving the axial skeleton Cartilaginous joints Entheses: ligamentous, tendinous, capsular, & fascial insertions into bone Synovial joints Broad interindividual disease variance Severity Temporal Progression Appendicular skeletal and extraskeletal manifestations
Prevalence 0-1.4% Epidemiology, Etiology Depending on ethnic group, HLA B27 status, diagnostic criteria Male:female ratio 2-3:1 Clearly polygenic:hla B27 (20-50% of risk) HLA B27(+) status: caucasian 8% Japanese<1% HLA B27(+) monozygotic twin studies: 63% concordance Autoimmune or autoinflammatory
Articulations of the Vertebral Arches Synovial Apophyseal/facet joints Costovertebral joints Syndesmosis Ligamenta flava Interspinous ligaments Intertransverse ligaments Supraspinous ligament Facet Joint Interspinous Ligament Supraspinous Ligament Ligamentum Flavum ALL Intertransverse Ligament PLL
Articulations of the Vertebral Bodies AF NP Cartilaginous endplate Calcified endplate ALL PLL
Articulations of the Vertebral Bodies AF NP Cartilaginous endplate Calcified endplate Sharpey`s Fibers (Entheses) ALL PLL
Early Radiographic Features Romanus lesions erosive lesions of the superoanterior and inferoanterior aspects of the vertebral bodies Shiny corner reactive sclerosis/eburnation following inflammatory activity Squaring of anterior vertebra
Syndesmophytosis Bamboo Spine Progressive syndesmophyte formation
Late Radiographic Features Dagger sign Calcification of the interspinous and supraspinous ligaments
Late Radiographic Features Trolley track sign Apophyseal joint ankylosis Capsular ossification Intraarticular ankylosis
Inflammation and Ankylosis Dissociated mechanisms? Syndesmophytes are more likely to develop at sites of prior inflammation
Inflammation and Ankylosis Dissociated mechanisms? Syndesmophytes are more likely to develop at sites of prior inflammation But most syndesmophytes appear without any preceding inflammation
Inflammation and Ankylosis Dissociated mechanisms? Syndesmophytes are more likely to develop at sites of prior inflammation But most syndesmophytes appear without any preceding inflammation Early inflammation may merely instigate the initial events of bony formation which subsequently continues largely independent of inflammatory activity
Summary A case of Ankylosing spondylitis was presented The importance of the Sharpey fibers in the pathogenesis of ankylosing spondylitis was discussed
Thank You Biography written by David Tucker Thought to be the 1st written account of Ankylosing Spondylitis in the US (1858)
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