Lee, RKT

Peh, WCG

HKU Scholars Hub

Title Radiological Conference: Rheumatoid arthritisAuthor(s) Lee, RKT; Peh, WCGCitation Hong Kong Practitioner, 1999, v. 21 n. 2, p. 80-83Issued Date 1999URL http://hdl.handle.net/10722/44681Rights Creative Commons: Attribution 3.0 Hong Kong LicenseRADIOLOGICAL CONFERENCEClinical History:A 43-year-old man presented with neck and shoulder pain. Cervical spine radiographs (Figures 1 & 2) weretaken.Figure 1: Lateral cervical spine radio-graph, taken in flexionFigure 2: Lateral cervical spine radio-graph, taken in extensionAnsweronpage 82What is the diagnosis?a) Rheumatoid arthritisb) Ankylosing spondylitisc) Klippel-Feil syndromed) Metastasis to C2 vertebrae) Retropharyngeal abscessThis radiology case was prepared by: Dr. R.K.T. Lee,Medical Officer.Professor W.C.G. Peh,Department of Diagnostic Radiology,The University of Hong Kong,Queen Mary Hospital.(Continued on page 82)80mm, A m m II «*•* A S <#* j^% ^iilff.|JE?a) Rheumatoid arthritisOn the radiographs of the cervical spine, the atlanto-axial distance is increased on the flexion view (Figure3), It measures approximately 8mm in this patient.Normally, it should measure up to 3 mm in adults and upto 5 mm in width in children. The atlanto-axial distanceis normal on the extension view (Figure 4). No bonyerosion is seen in the odontoid process, and the rest ofthe cervical vertebra is otherwise normal. There is noabnormal prevertebral soft tissue swelling.Figure 3: Same radiograph as Figure 1 with theaddition of arrows. The widenedatlanto-axial distance is indicated byarrowsFigure 4: Same radiograph as Figure 2 with theof arrows. The atlanto-axiaidistance (arrows) is normal in thispositionDiscussionRheumatoid arthritisThe radiological findings are typical of anterioratlanto-axial subluxation. The condition is suspectedwhen the distance between the posterior border of theanterior arch of C1 and the anterior border of the odontoidprocess of C2 vertebra exceeds 3 mm in adults and olderchildren, or 5 mm in younger children, or if theinterosseous distance changes considerably betweenflexion and extension on lateral radiographs.1 Atlanto-axial subluxation occurs in 20-25% of patients withrheumatoid arthritis, and may be evident in early stagesof the disease.2 It is related to transverse ligament laxitydue to synovial inflammation and hyperaemia of theadjacent articulations.82Hong Kong Practitioner 21 (2) February 1999RADIOLOGICAL CONFERENCEApart from anterior subluxation, vertical subluxationat C1-C2 is also observed in rheumatoid arthritis patients,which when extensive, can be fatal as the spinal cord andc e r v i c o m e d u l l a r y j u n c t i o n of the cord may becompressed. It occurs in 5-22% of patients.2 Lateralsubluxation of the atlanto-axial joints affects 10-20% ofcases. The clinical course of patients with atlanto-axialsubluxat ion is variable, ranging from non-progressivemild symptoms to disabling neurological abnormali t iesthat require operative in tervent ion . Magnetic resonanceimaging performed w i t h p a t i e n t in both f l ex ion ande x t e n s i o n p o s i t i o n s wou ld be h e l p f u l to assess thea d e q u a c y of the n e u r a l c ana l to e x c l u d e cord-compression. Since rheumatoid arthritis is a multi-organdisorder with symmetrical erosive arthritis of the synovialjoints, further investigation would depend on the clinicalpresentation.Ankylosing spondylitisAnkylos ing spondyl i t is is a chronic inflammatorydisorder affecting principally the axial skeleton, causingal terat ions in synovial and car t i laginous joints, and ats i tes of tendon and l i g a m e n t a t t a c h m e n t to bone.Insidious onset of back pain in a young adult would bet h e t y p i c a l c l i n i c a l m a n i f e s t a t i o n . C l a s s i c a l l y ,radiographical changes are init ially noted in the sacroiliacjo in ts , and then the thoracolumbar and lumbosacraljunctions. Cervical involvement tends to occur in thelater stages of the disease.2 By that time, other typicalfeatures such as bamboo spine, posterior element fusionand established sacroilii t is should be evident, none ofwhich is present in our patient.Klippel-Feil syndromeThe Klippel-Feil syndrome is a rare disordercharacterised by a short neck, low hairline and limitedneck movement due to ce rv ica l vertebral fusion.Segmental defects in the cervical spine produces blockvertebrae, most commonly affecting C2-3 and C5-6levels. This syndrome is frequently associated with otheranomal ies , such as moderate- to-severe scol iosis ,Sprengel 's shoulder, cervical ribs and geni tour inaryabnormal i t ies . ' Our patient does not have any of theclinical or radiological features of this syndrome.MetastasisThe spine is a frequent site of skeletal metastases,wi th the thoracic and lumbar levels mainly being affected.Metastases occur more commonly in the vertebral bodiesthan in the posterior elements.2 Carcinomas of the lung,breas t and pros ta te are among the most f r e q u e n tm a l i g n a n t t u m o u r s p r o d u c i n g s p i n a l metastases .Metastasis to C2 causing atlanto-axial subluxation is rare.There is no osteolytic or sclerotic lesion present on theradiographs, and moreover, our pat ient has no knownprimary tumour.Retropharyngeal abscessRetropharyngeal abscess may be caused by upperrespiratory tract infection, perforat ing in ju ry of thepharynx or oesophagus, or suppuration of infected lymphnodes. It usually occurs in patients less than one year old,with a clinical presentation of fever, neck stiffness anddysphagia. Radiographically, there is thickening of theretropharyngeal space exceeding % of the anteroposteriordiameter of the vertebral body. The retropharyngealswel l ing may contain gas or a gas-fluid level . 3 Theairway may be displaced anteriorly. Both the clinical andradiological features of retropharyngeal abscess areabsent in our patient. •References1. Chapman S, Nakielny R. Aids to Radiological Differential Diagnosis. 3rded. WB Saunders Company, London. 1995;p83.2. Resnick D. Bone and Joint Imaging. WB Saunders Company, Philadelphia.1989;pp277-279,309,871 -873,1199.3. Dahnert W. Radiology Review Manual. 3rd ed. Will iams & Wilkins,Baltimore, 1996;p293.83

Radiological Conference: Rheumatoid arthritis

http://hub.hku.hk/bitstream/10722/44681/1/52294.pdf

Radiological Conference: Rheumatoid arthritis

Abstract

Similar works

Full text

Available Versions

HKU Scholars Hub