22q11.2 deletion syndrome: are motor deficits more than expected for IQ level?

Objective: To examine motor function in children with 22q11.2 deletion syndrome (22q11.2) and a Full Scale IQ (FSIQ) comparable control group.

Study Design: This study was part of a prospective study of neuropsychological function in children 9 to 15 years of age with 22q11.2 and community control subjects and included children from these two populations with comparable FSIQs.

Results: Verbal IQs on the WISC-R for 40 children with 22q11.2 (88.4) and 24 community control subjects (87.2) were not different (P=.563). However, the performance IQs were (22q11.2; 81.1 vs community controls; 89.3; P<.001). On the Visual Motor Inventory, there was no difference between the standard scores of the two groups (22q11.2; 93.0 vs community control subjects; 98.1; P=.336) but on the motor coordination part of the Visual Motor Inventory, the scores of the 22q11.2 deletion syndrome group were lower (77.2 vs 89.3; P=.002). On the general neurologic examination (P=.906), the tone examination (P=.705), and the ball skills part of the Motor Battery, (P=.378), there were no differences. However, on the axial stability part of the Motor Battery, the children with 22q11.2 exhibited less good balance (P=.026).

Conclusions: School-aged children with 22q11.2 have specific motor deficits in axial stability and graphomotor skills.