Session Information
Session Type: Abstract Submissions (ACR)
Background/Purpose:
There is increasing evidence to suggest that bone marrow lesions (BMLs) play a key role in the pathogenesis of OA. Whilst many studies have focused on short and medium term changes in BMLs, no study has explored BMLs over longer timeframes. The aim of this study was to describe the natural history of knee BMLs and their association with knee pain over eight years.
Methods:
199 subjects which consisted of 109 adult offspring of subjects who had a knee replacement and 90 controls who were initially matched by age and sex were studied. BMLs were measured at the two and ten year follow-ups using T2 weighted fat saturation MRI measuring the maximum area of the lesion at the medial and lateral tibial/femoral and patella sites. Knee pain was assessed by the Western Ontario and McMaster Universities Arthritis Index (WOMAC).
Multiple linear and logistic regression models were performed to investigate potential associations between BMLs and pain.
Results:
At the two year follow-up, 64% of participants (n=128/199) had one or more BMLs, with a total of 231 BMLs present. Over eight years, of the 231 BMLs, 71% (164/231) increased in size, 8% (18/231) remained stable and 21% (49/231) decreased in size or resolved completely (Figure 1). Of those participants with no BMLs at baseline (71/199), 52% (37/71) developed one or more incident BMLs. In the whole sample, 31% of participants (62/199) developed a new BML at 1 site, 22% (44/199) at 2 sites, 9% (18/199) at 3 sites and 1% (2/199) at 4 sites or more. BML natural history did not vary between offspring and controls.
After adjusting for age, sex and BMI, the development of a new BML was associated with developing pain in those without pain at baseline (β=3.71, 95% CI 1.02-6.41). Those with a large BML at two years also had greater odds of having pain at ten years (OR=1.95, 95% CI 1.05-3.62). Eight year change in total BML size predicted an increase in total WOMAC pain in offspring but not controls (Table 1). The magnitude of the association in offspring was stronger in males as compared to females.
Conclusion:
Over eight years, the proportion of BMLs increasing in size was more than triple those decreasing in size and stable BMLs were rare. Incident BMLs were common, with slightly over half of our participants developing new BMLs, whilst one-fifth of BMLs resolved. Change in BML size was associated with pain only in those with a strong family history of OA, suggesting that knee pain associated with BMLs may have a genetic component.
Table 1: Change in WOMAC pain score per change in BML size (linear regression) |
||||
|
Univariable β (95% CI) |
Multivariable* β (95% CI) |
Females* β (95% CI) |
Males* β (95% CI) |
Total |
0.46 (-0.17, 1.08) |
0.47 ( -0.16, 1.11) |
0.14 (-0.58, 0.87) |
2.49 (0.86, 4.12) |
Controls |
-0.09 ( -0.71, 0.53) |
-0.04 (-0.69, 0.60) |
-0.14 (-0.93, 0.66) |
1.56 (-1.10, 4.23) |
Offspring |
2.68 (1.22, 4.13) |
2.65 (1.20, 4.10) |
2.22 (0.10, 4.34) |
3.17 (1.04, 5.31) |
*Adjusted for age, sex, BMI. β coefficients are the change in pain score per unit change in BML size (cm2). |
Figure1: Natural history of BMLs
Disclosure:
Y. C. Foong,
None;
H. I. Khan,
None;
D. Aitken,
None;
C. Ding,
None;
F. Cicuttini,
None;
G. Jones,
None.
« Back to 2013 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/the-clinical-significance-and-natural-history-of-knee-bone-marrow-lesions-over-8-years/