suggestions for a reproducible scoring system
Transcription
suggestions for a reproducible scoring system
HAND PHOTOGRAPHY AS A METHOD FOR DIAGNOSING HAND OSTEOARTHRITIS: SUGGESTIONS FOR A REPRODUCIBLE SCORING SYSTEM Reference photo collection Helgi Jónsson and Guðrún P. Helgadóttir May 2007 Copyright: Helgi Jónsson and Guðrún P. Helgadóttir. Reproduction only on written permission from authors. e-mail: [email protected] www.handphotos.tk In this booklet, we propose the use of high quality hand photographs as a method for diagnosing hand osteoarthritis (HOA) and take the first step towards suggesting a reproducible scoring system for HOA on hand photographs. The photographs were taken as part of the AGES-Reykjavik study. All participants were aged 69 or older. The photographs were taken with a Fuji Finepix 6800 zoom camera with images taken at 2800x2200 pixels. The camera was mounted on a tripod with a fixed distance to a velvet board with markers for thumb positioning. The quality of the digital images is important in order for the readers to be able to visually assess the degree of enlargement and deformity. Some detail is lost in the printed version but a digital copy of this brochure can be found at www.handphotos.tk. In preparing the scoring system, we initially registered a number of variables that we suspected to be related to HOA in each joint. After comparing our results with hand radiographs, we chose the variables most likely to be associated with radiographic HOA. Each individual joint was graded separately for the visual signs of the presence of hand OA. Several factors are of importance, such as hard tissue enlargement, visible soft tissue swelling, position and deformity. We scored the distal interphalangeal (DIP) and the proximal interphalangeal joints (PIP) on a 0-3 scale as follows: 0=no evidence of OA, 1=suspected but not definite OA, 2= definite moderate OA, 3= severe OA. For the DIP joints, we found that deformity of joint without hard tissue enlargement did not justify the diagnosis of hand OA on its own but when deformity was severe (>30°), the recorded score was raised by one (1) unit (to a maximum of 3). Reference photos for the grading of DIP and PIP joints are shown in figures 1-8. For uniformity of presentation we selected to show the right DIP2 and PIP3 joints. For assessment of OA of the first carpometacarpal joints (CMC1), a slightly different approach was needed. Two different findings, enlargement and position were most clearly related to OA in that joint. Position reflects palmar migration of the base of the first metacarpal bone and is reflected on photography by a number of factors, including disappearance of the normal configuration of the CMC1 joint, medial rotation of the thumb showing increased folding of the skin over the first metacarpal joint (MCP1) and sometimes hyperextension of that joint. Both enlargement and position were scored on a 0-3 scale, (0=no evidence of OA, 1=suspected but not definite OA, 2= definite moderate OA, 3= severe OA.) and subsequently added, giving a score of 0-6 which was translated into a 0-3 score as follows: (0= Normal joint, 1= Doubtful OA, 2-3= Definite OA and 4+= Severe OA). Reference photos for the CMC1 joints are shown in figures 9-15. Fig. 1. Unaffected DIP joints. Fig. 2. Grade 1 DIP joints. Some evidence of OA but not fulfilling the criteria for definite disease. Fig. 3. Grade 2 DIP joints. Definite moderate OA. Fig. 4. Grade 3 DIP joints. Severe hand OA defined by large Heberden´s nodes with or without deformity. Fig. 5. Unaffected PIP joints. Fig. 6. Grade 1 PIP joints. Some evidence of OA but not fulfilling the criteria for definite disease. Fig. 7. Grade 2 PIP joints. Definite moderate OA. Fig. 8. Grade 3 PIP joints. Severe hand OA defined by large Bouchard´s nodes with or without deformity. Fig. 9. Both photos show unaffected CMC1 joints. The first score refers to bony enlargement and the second to thumb position. Fig. 10. Both photos show unaffected CMC1 joints. The first score refers to bony enlargement and the second to thumb position. Fig. 11. The photos show suspected or mild CMC1 OA of the CMC1 joints. The first score refers to bony enlargement and the second to thumb position. Thus, the right thumb on the lower photo scores as definite OA(1+1=2). Fig. 12. Definite CMC1 OA. Upper right hand scores 2+1=3 =definite OA, and lower left hand scores 2+2= severe OA. Fig. 13. Further examples of severe CMC1 OA. Upper right hand and lower left hand both qualify as severe CMC1 OA. Fig. 14. Further examples of different stages of CMC1 OA. Fig. 15. Further examples of different stages of CMC1 OA. Acknowledgements The making of this booklet was funded by the Icelandic Osteoarthritis Fund and the University of Iceland Research Fund. We thank the Icelandic Heart Association Age, Gene/Environment Susceptibility-Reykjavik Study (AGES-Reykjavik) for providing the photographs.