Table 1.

Summary of neonatal foot length studies and models

Description	Streeter [8]	Usher [13]	Jordaan [15]	Chatterjee [10]	Mercer [7]	Mhaskar [11]	Merz [12]	Meirowitz [16]
Year	1920	1969	1982	1986	1987	1988	2000	2000
n	704	300	132 live born, 94 abortus	53	223	105	610	5372
Purpose	Determine weight, sitting height, head size and foot length	Determine seven anthropometric measurements in normal newborns	Compare FL and BW with Streeter data; estimate BW from FL	Fetal foot length as determinant of GA	Compare fetal and postnatal foot lengths	Correlate FL with GA	Reference range for fetal foot growth	Evaluate effect of growth disturbances in SGA and LGA fetuses
Population	America-Caucasian	Canada, Caucasian	South Africa	Mexico	USA	India	Germany	American 85%, Caucasian 10%, African American 10.9% SGA incidence
GA (weeks)	8.5–40, pathology specimens (formalin)	25–40	Live born: 23–44, abortus: 16–20	14–40	11–43	13–42	12–42	15–37
Method of confirm GA	LMP	LMP	Clinical estimates and antenatal ultrasound	EUS <14 weeks	Secure dates and EUS	Not specified	EUS <12 weeks	Two week concordance between LMP and US
Method FL measurement	Sliding compass	Metal millimetre rule	Specially constructed sliding calliper	Ultrasound	Ultrasound	Ultrasound;101 measured postnatally	Ultrasound	Ultrasound
FL measurement technique	Longest toe (first or second) to heel	Longest toe to heel	Heel to outstretched longest toe	Heel to end of big toe	Longest toe to heel	heel to tip of big toe; Postnatal measurements with a ruler	heel to tip of big toe	Not specified
Growth curve FL/GA	Curvilinear correlation	Curvilinear correlation	Curvilinear correlation	Linear	Curvilinear	Linear	Curvilinear	Curvilinear
Results	Growth curves for various parameters studied, including FL	Mean foot length values documented: ± SD 4.2–8.8% difference AGA vs. SGA; correlation FL and BW r = 0.95 and FL/COH 0.96	FL and BW r = 0.8152; insignificant difference with Streeter's data	r2 = 0.89, p << 0.0001 between GA and FL, only 5th, 50th and 95th centile	Similar to Streeter's data; FL/GA r2 = 0.98, reference range	GA/FL correlation r2 = 0.85, p < 0.001, BPD and FL, r4 = 0.91, p < 0.001. Antenatal FL correlated well with postnatal FL, measured within 3 days Correlated well with Streeter and Mercer data	FL leveled off slightly at 24/52—continued linear growth, values for 5th, 50th and 95th centile only; results for half week	Smoothed normogram for 5th, 10th, 50th, 90th and 95th centile

Notes. FL = foot length; BW = birth weight; COH = circumference of head; EUS = early ultrasound; BPD = biparietal diameter; US = ultrasound.