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: helgi@hi.is
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.