Marfan syndrome involves a genetic disorder of the connective tissue that is typically featured with a rather discriminating physical appearance that can be summarized to represent 'elongation' of body parts [dolichostenomelia]. The hand in Marfan syndrome can often be recognized at first glance through the fingers: they are commonly featured with 'spider fingers' [arachnodactyly] - a.k.a. 'extraordinary long fingers' [dolichodactyly]. This concerns a highly discriminating typical characteristic for the hand in this disorder, and... it is relatively rare in the hands of people who do not have Marfan syndrome!
Marfan syndrome is affecting about 1 in 5.000 births - with half of them undiagnosed as adults. One of the reasons why many Marfan adults continue to be undiagnosed is because Marfan syndrome is a rather complex disorder: there is actually no single feature seen in every Marfan person. The official process of diagnosis presents 7 different criteria that may lead to a diagnosis - according the 2010 revised Ghent Nosology. This implicates that patience & finance is always required for a proper diagnosis.
The HandResearch 'Marfan Syndrome Hand Test' is presented here as a quick & cost less 'screening tool' - providing people a clue (based on multiple dimensions of the hand) about their chance for having Marfan syndrome.
NOTICE: For adults a score of 17 or higher is required to pass the test (for children: 18 or higher), and an early validation study has indicated that more than half of Marfan people (confirmed by an official diagnosis) are likely to pass the 'Marfan Syndrome Hand Test' - NON-Marfan people are unlikely to pass the test (only a relatively small percentage of people with Loeys-Dietz syndrome & Ehler-Danlos syndrome may pass the test as well; even though people who have Beals syndrome also have a Marfanoid appearance, they are unlikely to pass the test due to the typical muscle contractors that result in inflexible hands).
Until august 21, 2013 this test has been validated with self-reports by 20 persons who have Marfan syndrome (16 Marfan persons passed the test, 3 Marfan persons scored in the 'borderline' category - indicative for various related syndromes, and 1 Marfan person didn't pass the test). Only 2 'false positives' spotted so far (1 person who has Loeys-Dietz syndrome + 1 person who has Ehler-Danlos syndrome).
The Marfan Syndrome Hand Test:
STEP 2 - advanced considerations!
After scoring the 10 hand signs, advanced considerations regarding the score can be made via an analysis of the numbers of 'hand dimensions' + the presence of other hand features (listed below):
- If a person scores 16 points through the combination of the 'hand length sign' (8 points) and the 'arm span sign' (8 points) OR the combination with the 'arm span sign' (8 points) plus the 'thumb sign' (4 points) & 'wrist sign' (4 points), the outcome of the test should be considered as 'positive' (just like when a person scores 17 points or higher);
- If a person scores points on (all) 3 hand dimensions, the probability for making a false diagnosis should be estimated at about half of the percentage suggest by the protocol;
- If a person has at least two of the '8 other Marfan hand signs' (see the next paragraph) the probability for making a false diagnosis should be estimated at about half of the percentage suggested by the protocol;
- If a person scores points for (all) 3 hand dimensions + has at least two of the '8 other Marfan hand signs', the probability for making a false diagnosis should be estimated about a quarter of the percentages suggested by the protocol.
The hand in Marfan syndrome:
8 other Marfan hand signs!
Beyond the guidelines described by the Marfan syndrome hand test there is a list of other hand features that are known for their significance in Marfan syndrome, including:
•  long, thin fingers (fingers)
•  dolichonychia [average length-width ratio for 10 nails: > 1.3] (fingernails)
•  camptodactyly (fingers)
•  clinodactyly (fingers)
•  extra digital transverse creases (fingers)
•  high positioned axial triradius (dermatoglyphics)
•  simian crease (hand lines)
•  Sydney line (hand lines)
Despite the significance of these 8 hand signs for Marfan syndrome, the discriminating value of these signs is usually much lower than the hand features included in the Marfan syndrome hand test; only the feature related to the fingernails (dolichonychia) is known for having a highly specific discriminating value for Marfan syndrome.
The hand in Marfan syndrome:
Multi-Perspective Palm Reading required!!
The innovative approach of Multi-Perspective Palm Reading (introduced in 2011) explains why a consideration of multiple dimensions of the hand is a requirement for recognizing Marfan syndrome. For, not all Marfan people have the two most typical hand shape characteristics that are featured with 'spider fingers' [arachnodactyly] - which is in usually described/defined by means of the 'thumb sign' (a.k.a. Steinberg sign) and the 'wrist sign' (a.k.a. Walker-Murdoch sign)
NOTICE: Additional advanced criteria for recognizing arachnodactyly have been described in the literature (e.g. in terms of the metacarpal index and skeletal maturity), however these are often not used in clinical practice.
For this reason a hand assessment for Marfan syndrome also requires a consideration of hand features beyond the hand shape: the skin quality and the motorics are essential as well!
Multiple other syndromes show significant overlap with the hand in Marfan syndrome:
- Loeys-Dietz syndrome (LDS - until 2006 it was known as Marfan type 2), has significant overlap with Marfan syndrome especially for 6 hand features related to the hand dimensions 'skin quality' & 'motorics'.  Camptodactyly is a common feature seen in the hand (much more often than in Marfan syndrome). However, in LDS the Marfanoid appearance is missing:  no excessive arm span. BODY HEIGHT:  No excessive tall body height;  FOOT: A club foot may be present.
- Ehler-Danlos syndrome (EDS) has significant overlap with Marfan syndrome on all three hand dimensions. However, LDS distinguishes itself from Marfan syndrome through the following features:  excessive arm span is missing (arm span vs. body height ratio < 1.05);  translucent skin that bruises easily and usually combined with  severe skin problems;  swan-nek deformity of the fingers.  FOOT: A club foot may be present.
• Hand shape assessment 2.0
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the 'Marfan syndrome hand test' at the Multi-Perspective Palm Reading blog.