Knee alignment does not predict incident osteoarthritis: The Framingham osteoarthritis study
Open Access
- 28 March 2007
- journal article
- research article
- Published by Wiley in Arthritis & Rheumatism
- Vol. 56 (4), 1212-1218
- https://doi.org/10.1002/art.22508
Abstract
Objective To examine the relationship of knee malalignment to the occurrence of knee osteoarthritis (OA) among subjects without radiographic OA at baseline to determine whether malalignment is a risk factor for incident disease or simply a marker of increasing disease severity. Methods We selected 110 incident tibiofemoral (TF) OA case knees (76 subjects) and 356 random control knees (178 subjects) from among participants in the Framingham Osteoarthritis Study. Case knees did not have OA at baseline (1992–1994 examination) but had developed OA (Kellgren/Lawrence grade ≥2) at followup (2002–2005 examination) (mean of 8.75 years between examinations). Control knees did not have OA at baseline. Standardized digital radiographs of the fully extended knee with weight-bearing were read using a standard protocol and eFilm viewing software. We measured the anatomic axis, the condylar angle, the tibial plateau angle, and the condylar tibial plateau angle. The interobserver intraclass correlation coefficient (ICC) ranged from 0.93 to 0.96 and the intraobserver ICC from 0.94 to 0.97. In a knee-specific analysis, we examined the relationship of each alignment measurement to the risk of TF OA using generalized estimating equations, adjusting for age, sex, and body mass index (BMI). We used the same approach to assess the association between each alignment measurement and the risk of medial TF OA. Results Subjects in the case population were older and had a higher BMI than the controls. The alignment values were normally distributed and were not different between the cases and the controls. After adjustment for age, sex and BMI, there was no significant increase in incident OA in the highest quartile compared with the lowest quartile category for any of the alignment measures (P for trend for anatomic axis and condylar tibial plateau angle was 0.83 and 0.80, respectively). Similar results were also observed for medial compartment OA. Conclusion We found that baseline knee alignment is not associated with either incident radiographic TF OA or medial TF OA. These results suggest that malalignment is not a risk factor for OA, but rather is a marker of disease severity and/or its progression.Keywords
This publication has 16 references indexed in Scilit:
- A comparative assessment of alignment angle of the knee by radiographic and physical examination methodsArthritis & Rheumatism, 2005
- Development of radiographic changes of osteoarthritis in the """Chingford knee""" reflects progression of disease or non-standardised positioning of the joint rather than incident diseaseAnnals Of The Rheumatic Diseases, 2003
- Bone Marrow Edema and Its Relation to Progression of Knee OsteoarthritisAnnals of Internal Medicine, 2003
- Quadriceps Strength and Osteoarthritis Progression in Malaligned and Lax KneesAnnals of Internal Medicine, 2003
- The influence of alignment on risk of knee osteoarthritis progression according to baseline stage of diseaseArthritis & Rheumatism, 2002
- The mechanism of the effect of obesity in knee osteoarthritis: The mediating role of malalignmentArthritis & Rheumatism, 2000
- A connective tissue disease screening questionnaire for population studiesAnnals of Epidemiology, 1995
- Incidence and progression of osteoarthritis in women with unilateral knee disease in the general population: the effect of obesity.Annals Of The Rheumatic Diseases, 1994
- Radiographic patterns and associations of osteoarthritis of the knee in patients referred to hospital.Annals Of The Rheumatic Diseases, 1993
- The prevalence of knee osteoarthritis in the elderly. the framingham osteoarthritis studyArthritis & Rheumatism, 1987