Background: Rice farming activities involve prolonged manual work and human–machine
interaction. Prolonged farming risk-exposure may result in lower limb malalignment. This
malalignment may increase the risk of lower extremity injury and physical disabilities. However,
the prevalence and factors associated with lower extremity malalignment have not yet been
reported. This study aimed to investigate the prevalence and risk factors of lower extremity
malalignment among rice farmers.
Methods: A cross-sectional survey was conducted with 249 rice farmers. Lower extremity
alignment assessment included: pelvic tilt angle, limb length equality, femoral torsion, quadriceps
(Q) angle, tibiofemoral angle, genu recurvatum, rearfoot angle, and medial longitudinal arch
angle. Descriptive statistics were used to analyze participant characteristics and prevalence of
lower extremity malalignment. Logistic regression analysis was used to identify risk factors.
Results: The highest prevalence of lower extremity malalignment was foot pronation (36.14%),
followed by the abnormal Q angle (34.94%), tibiofemoral angle (31.73%), pelvic tilt angle
(30.52%), femoral antetorsion (28.11%), limb length inequality (22.49%), tibial torsion
(21.29%), and genu recurvatum (11.24%). In females, the risk factors were abnormal Q angle,
tibiofemoral angle, and genu recurvatum. Being overweight was a risk factor for abnormal pelvic
tilt angle, Q angle, and tibiofemoral angle. Age was a risk factor for limb length inequality.
Years of farming were a major risk factor for abnormal Q angle, tibiofemoral angle, and foot
malalignment.
Conclusion: Prevalence of lower extremity malalignment was reported in this study. Female
sex, being overweight, and years of farming were major risk factors for lower extremity malalignment.
Lower extremity screening should assist in the identification of foot and knee malalignment
in rice farmers. This may then lead to early prevention of musculoskeletal disorders
arising from such malalignment.
Keywords: lower extremity malalignment, prevalence, rice farmer, risk factors