Quadriceps strength is negatively associated with knee joint structural abnormalities—data from osteoarthritis initiative

Table 1 Baseline characteristics of the participants and the knees

Characteristics	Men	Women	P
Participants^a
Race (%)	88.5	80.0	0.001
BMI (kg/m²)	29.4 ± 3.9	29.4 ± 5.1	0.688
Age (years)	61.9 ± 9.0	61.7 ± 8.7	0.589
Knees^b
KL grade, 0/1/2/3/4, (%)	16.4/24.3/19.6/26.0/13.8	16.5/31.5/26.1/18.5/7.4	< 0.001
Injury (%)	40.0%	28.2%	< 0.001
Surgery (%)	25.9%	12.5%	< 0.001
Quadriceps strength (Nm/kg)	1.5 ± 0.5	1.1 ± 0.4	< 0.001
Cartilage damage
MTF (range 0 to 15)	4.0 ± 4.0	2.6 ± 3.3	< 0.001
LTF (range 0 to 15)	1.7 ± 2.7	1.8 ± 2.7	0.480
MPF (range 0 to 6)	1.9 ± 1.5	2.5 ± 1.5	< 0.001
LPF (range 0 to 6)	1.5 ± 1.8	1.8 ± 1.9	0.001
BMLs
MTF (range 0 to 15)	1.8 ± 2.6	1.0 ± 2.0	< 0.001
LTF (range 0 to 15)	0.6 ± 1.5	0.5 ± 1.5	0.287
MPF (range 0 to 6)	0.6 ± 0.9	0.9 ± 1.1	< 0.001
LPF (range 0 to 6)	0.8 ± 1.3	1.0 ± 1.4	0.008
Synovitis
Effusion-synovitis, 0/1/2/3, (%)	41.8/34.6/17.5/6.2	43.9/38.2/13.2/4.7	0.059
Hoffa-synovitis, 0/1/2/3, (%)	34.9/49.5/13.7/1.9	45.0/47.0/7.8/0.2	< 0.001

Race, white people percentage, BMI Body mass index, KL Kellgren-Lawrence, MTF Medial tibiofemoral, LTF Lateral tibiofemoral, MPF Medial patellofemoral, LPF Lateral patellofemoral, BMLs Bone marrow lesions, Effusion-synovitis, graded as 0/1/2/3 according to MOAKS system; Hoffa-synovitis, graded as 0/1/2/3 according to MOAKS system; MOAKS, magnetic resonance imaging Osteoarthritis Knee Score
Bold denoted statistical significance (P < 0.05)
^a For all, n = 1338; for men, n = 523; for women, n = 815
^b For all, n = 1505; for men, n = 584; for women, n = 921

ISSN: 1471-2474