title: Association of radiological hand osteoarthritis with bone mineral mass: a population study.
abstract: OBJECTIVE
  A number of previous studies have reported an inverse relationship between osteoarthritis and osteoporosis. However, the association has remained controversial because osteoarthritis in hand joints seems to associate differently from osteoarthritis in weight-bearing joints with bone mineral mass. We studied osteoarthritis in distal interphalangeal (DIP) joints and osteoarthritis in the base of the thumb (CMC-1) for their cross-sectional associations with metacarpal cortical bone mineral mass, and for their prediction of calcaneal broadband ultrasound attenuation.
  
  
  METHODS
  A population sample of 8000 Finns aged 30 yr and over was invited to a comprehensive health examination in 1978-1980; 90% complied. Hand radiographs were taken from 3568 participants to diagnose osteoarthritis in various hand joints, and to determine two indicators of cortical bone mineral mass, the combined cortical thickness (CCT) and the metacarpal index (MCI). Calcaneal broadband ultrasound attenuation was measured 20 yr later in 340 of these participants with the Sahara sonometer.
  
  
  RESULTS
  In the cross-sectional setting, osteoarthritis in the DIP joints and osteoarthritis in the base of the thumb (CMC-1) were significantly associated with low CCT and low MCI. These associations were proportional to the radiological severity of osteoarthritis. In the follow-up setting, symmetrical DIP osteoarthritis adjusted for age, sex, body mass index, smoking, education, workload and MCI significantly predicted low values of broadband ultrasound attenuation.
  
  
  CONCLUSIONS
  Our results indicate a direct relation of both radiological DIP osteoarthritis and CMC-1 osteoarthritis with low cortical bone mineral mass, in proportion to the severity of osteoarthritis. The presence of symmetrical DIP osteoarthritis, a possible indicator of generalized osteoarthritis, suggests an increased risk of osteoporosis over time.
authors.affiliation: Bone and Cartilage Research Unit (BCRU) and Department of General Practice and Public Health, University of Kuopio, Kuopio, Finland. mhaara@hytti.uku.fi
authors.forename: M M
authors.initials: MM
authors.lastname: Haara
authors.forename: J P A
authors.initials: JP
authors.lastname: Arokoski
authors.forename: H
authors.initials: H
authors.lastname: Kröger
authors.forename: A
authors.initials: A
authors.lastname: Kärkkäinen
authors.forename: P
authors.initials: P
authors.lastname: Manninen
authors.forename: P
authors.initials: P
authors.lastname: Knekt
authors.forename: O
authors.initials: O
authors.lastname: Impivaara
authors.forename: M
authors.initials: M
authors.lastname: Heliövaara
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D002111:Calcaneus / Q000000981:diagnostic imaging / Q000503:physiopathology; D004812:Epidemiologic Methods; D005260:Female; D005387:Finland / Q000453:epidemiology; D050823:Hand Joints / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D050279:Metacarpal Bones / Q000503:physiopathology; D008875:Middle Aged; D010003:Osteoarthritis / Q000150:complications* / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000503:physiopathology; D010024:Osteoporosis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology*; D011859:Radiography; D012720:Severity of Illness Index; D014463:Ultrasonography