Bone and cartilage characteristics in postmenopausal women with mild knee radiographic osteoarthritis and those without radiographic osteoarthritis.
OBJECTIVE
To evaluate the association between radiographically-assessed knee osteoarthritis and femoral neck bone characteristics in women with mild knee radiographic osteoarthritis and those without radiographic osteoarthritis.


METHODS
Ninety postmenopausal women (mean age [SD], 58 [4] years; height, 163 [6] cm; weight, 71 [11] kg) participated in this cross-sectional study. The severity of radiographic knee osteoarthritis was defined using Kellgren-Lawrence grades 0=normal (n=12), 1=doubtful (n=25) or 2=minimal (n=53). Femoral neck bone mineral content (BMC), section modulus (Z), and cross-sectional area (CSA) were measured with DXA. The biochemical composition of ipsilateral knee cartilage was estimated using quantitative MRI measures, T2 mapping and dGEMRIC. The associations between radiographic knee osteoarthritis grades and bone and cartilage characteristics were analyzed using generalized linear models.


RESULTS
Age-, height-, and weight-adjusted femoral neck BMC (p for linearity=0.019), Z (p for linearity=0.033), and CSA (p for linearity=0.019) increased significantly with higher knee osteoarthritis grades. There was no linear relationship between osteoarthritis grades and knee cartilage indices.


CONCLUSIONS
Increased DXA assessed hip bone strength is related to knee osteoarthritis severity. These results are hypothesis driven that there is an inverse relationship between osteoarthritis and osteoporosis. However, MRI assessed measures of cartilage do not discriminate mild radiographic osteoarthritis severity.
Department of Physical Medicine and Rehabilitation, Central Finland Central Hospital, Jyväskylä, Finland.
J
J
Multanen
A
A
Heinonen
A
A
Häkkinen
H
H
Kautiainen
U M
UM
Kujala
E
E
Lammentausta
T
T
Jämsä
I
I
Kiviranta
M T
MT
Nieminen
D015502:Absorptiometry, Photon; D000368:Aged; D015519:Bone Density; D001842:Bone and Bones / Q000000981:diagnostic imaging* / Q000473:pathology; D002356:Cartilage / Q000000981:diagnostic imaging* / Q000473:pathology; D003430:Cross-Sectional Studies; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000473:pathology; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology; D010024:Osteoporosis / Q000150:complications; D017698:Postmenopause