Relationship between stature and tibial length for children with moderate-to-severe cerebral palsy

Objective: To derive the equation for estimating stature, based on tibial length, for children with moderate-to-severe cerebral palsy (CP) and lower limb joint contracture or scoliosis.

Methods: The participants (3-12-years-old) included 50 children with moderate-to-severe CP (mean age, 8.3±2.4 years) and 38 typically developed (TD) children (mean age, 7.5±2.6 years). Thirty-four (68%) of the children with CP had a gross motor function classification system level of V. Furthermore, 40 (80%) had definite lower limb joint contracture or scoliosis. The stature and the tibial length measurements of all participants were determined. Regression equations to estimate stature, based on tibial lengths, were determined for both TD children and children with CP. Moreover, regression equations defining the relationship between tibial length and age were compared between the two groups of children, using multiple regression analysis.

Results: The regression equations for estimating stature, based on tibial length, were stature=tibial length×3.25+34.45 [cm], R(2)=0.91 (TD children), and stature=tibial length×3.42+31.82 [cm], R(2)=0.81 (CP children). In children with CP, tibial lengths were significantly shorter than those in similarly aged TD children.

Conclusion: The stature of children with moderate-to-severe CP can be estimated from their tibial lengths, regardless of the presence of joint contracture or scoliosis. The tibial length may be a proxy for estimating stature during the growth assessment of children with moderate-to-severe CP.