Foot posture, foot function and low back pain: the Framingham Foot Study.
OBJECTIVE
Abnormal foot posture and function have been proposed as possible risk factors for low back pain, but this has not been examined in detail. The objective of this study was to explore the associations of foot posture and foot function with low back pain in 1930 members of the Framingham Study (2002-05).


METHODS
Low back pain, aching or stiffness on most days was documented on a body chart. Foot posture was categorized as normal, planus or cavus using static weight-bearing measurements of the arch index. Foot function was categorized as normal, pronated or supinated using the centre of pressure excursion index derived from dynamic foot pressure measurements. Sex-specific multivariate logistic regression models were used to examine the associations of foot posture, foot function and asymmetry with low back pain, adjusting for confounding variables.


RESULTS
Foot posture showed no association with low back pain. However, pronated foot function was associated with low back pain in women [odds ratio (OR) = 1.51, 95% CI 1.1, 2.07, P = 0.011] and this remained significant after adjusting for age, weight, smoking and depressive symptoms (OR = 1.48, 95% CI 1.07, 2.05, P = 0.018).


CONCLUSIONS
These findings suggest that pronated foot function may contribute to low back symptoms in women. Interventions that modify foot function, such as orthoses, may therefore have a role in the prevention and treatment of low back pain.
Institute for Aging Research, Hebrew Senior Life, 1200 Centre Street, Boston, MA 02131, USA. hannan@hsl.harvard.edu.
Hylton B
HB
Menz
Alyssa B
AB
Dufour
Jody L
JL
Riskowski
Howard J
HJ
Hillstrom
Marian T
MT
Hannan
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D005528:Foot / Q000503:physiopathology*; D005534:Foot Diseases / Q000503:physiopathology*; D006801:Humans; D017116:Low Back Pain / Q000209:etiology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D011403:Pronation / Q000502:physiology*; D012737:Sex Factors; D013484:Supination / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology
flatfoot; gait; low back pain; risk factors