Mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome): assessment of joint mobility and grip and pinch strength.
OBJECTIVE
To describe the profile of joint mobility and grip and pinch strength of MPS VI patients and to correlate this with urinary excretion of glycosaminoglycans (GAGs), ARSB activity, and the distance covered in a 6-minute walking test (6MWT).


METHODS
This was an observational study of 28 patients with MPS VI, who had not undergone specific treatment. All patients were assessed for amplitude of joint mobility (shoulder, elbow, and knee), grip and pinch strength and urinary GAG excretion and also performed the 6MWT.


RESULTS
Shoulder flexion exhibited the greatest limitation, with no correlation with age, followed by knee extension and elbow flexion, both of which were correlated inversely with age. Hand grip strength was compromised in all patients, and pinch strength exhibited a positive correlation with age.


CONCLUSIONS
The fact that restricted shoulder flexion was not correlated with age suggests that this finding is present early on in MPS VI and that it constitutes an important clinical sign that should arouse diagnostic suspicion of this disease. The amplitude of knee extension and elbow flexion, in turn, are possible markers of disease progression since they have a negative correlation with age. Further studies are needed to confirm these hypotheses.
Cardoso-Santos
Antonio
A
Faculdade de Medicina, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil. acsantos@hcpa.ufrgs.br
Azevedo
Ana C M M
AC
Fagondes
Simone
S
Burin
Maira G
MG
Giugliani
Roberto
R
Schwartz
Ida V D
IV
D002648:Child; D004551:Elbow Joint / Q000503:physiopathology; D005260:Female; D006025:Glycosaminoglycans / Q000652:urine; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D007719:Knee Joint / Q000503:physiopathology; D008297:Male; D009087:Mucopolysaccharidosis VI / Q000150:complications / Q000378:metabolism / Q000503:physiopathology*; D020051:N-Acetylgalactosamine-4-Sulfatase / Q000097:blood; D012016:Reference Values; D012785:Shoulder Joint / Q000503:physiopathology
D006025:Glycosaminoglycans; D020051:N-Acetylgalactosamine-4-Sulfatase