Table 3

Heritability estimates of tibiofemoral angle in 712 knees, from 180 sib pairs

Characteristics	H²	95% CI	p
Non-osteoarthritic knees
Tibiofemoral angle in right knee*	0.41	0.02 to 0.80	0.04
Tibiofemoral angle of right knee, adjusted for age, sex, BMI, history of meniscectomy or fracture	0.42	0.02 to 0.82	0.045
Tibiofemoral angle in left knee†	0.60	0.26 to 0.95	0.002
Tibiofemoral angle in left knee, adjusted for age, sex, BMI, history of meniscectomy or fracture	0.56	0.19 to 0.93	0.005
All knees
Tibiofemoral angle in right knee	0.48	0.19 to 0.76	0.002
Tibiofemoral angle of the right knee, adjusted for age, sex, BMI, history of meniscectomy or fracture, KL score‡	0.48	0.18 to 0.78	0.003
Tibiofemoral angle in left knee	0.38	0.09 to 0.67	0.01
Tibiofemoral angle of the left knee, adjusted for age, sex, BMI, history of meniscectomy or fracture, KL score‡	0.50	0.21 to 0.79	0.002

↵* Ninety-three families with both siblings with non-osteoarthritic (KL score <2) right knees
↵† 109 families with both siblings with non-osteoarthritic (KL score < 2) left knees
↵‡ KL score = KL score of right or left knee (0–4).
BMI, body mass index; H², heritability estimate; KL, Kellgren–Lawrence score.