 ### Description

Mirwald et al developed equations for estimating the number of years to peak height velocity (PHV) during adolescence. This can be used as an indicator of physical maturity, especially in athletes. The authors are from the University of Saskatchewan in Canada, University of Queensland in Australia and Katholieke Universiteit Leuven in Belgium.

Patient selection: pediatric patients from 8 to 16 years

Parameters:

(1) gender

(2) age

(3) standing height in cm

(4) sitting height in cm

(5) body weight in kg

leg length in cm =

= (standing height) - (sitting height)

maturity offset for a male = years from PHV for a male =

= (0.0002708 * (leg length) * (sitting height)) - (0.001663 * (age) * (leg length)) + (0.007216 * (age) * (sitting height)) + (0.02292 * (weight) / (height)) - 9.236

maturity offset for a female = years from PHV for a female =

= (0.0001882 * (leg length) * (sitting height)) + (0.0022 * (age) * (leg length)) + (0.005841 * (age) * (sitting height)) - (0.002658 * (age) * (weight)) + (0.07693 * (weight) / (height)) - 9.376

Interpretation:

• A negative number indicates an age younger than PHV while a positive number indicates that the PHV has passed.

Performance:

• The R-squared for both equations was 0.89. The SEE was 0.59 for males and 0.57 for females.

• Performance is best for males 12 to 16 years of age and for females 9 to 13 years of age.