[Ultrasound measurement of humeral torsion in children and adolescents with hemiplegic cerebral palsy].

BACKGROUND: Torsional deformity in the lower extremities is well known in children and adolescents with hemiplegic cerebral palsy, however, little or nothing is known about possible differences in torsional behavior of the upper extremities. Alterations of torsion in the lower extremities influence the gait, alterations in the rotation behavior of the upper extremities, for example after fractures, lead to limited movement of the arms or to an altered movement radius. The aim of this study was to investigate whether there is a difference in humeral torsion between affected and non-affected arms in children and adolescents with hemiplegic cerebral palsy and which factors play a decisive role. PATIENTS AND METHODS: A total of 33 children and adolescents with hemiplegic cerebral palsy (mean age 9.7 years, range 3-16 years) answered a questionnaire and were examined clinically, photographically and with a new ultrasound method. Severity of cerebral palsy was classified into three levels. Ultrasound measurements of humeral torsion were compared with the results from a normal collective (n=149).
RESULTS: In approximately half (n=16, 48.5%) of the 33 children investigated, humeral torsion was directed more internally, in 17 (51.5%) children humeral torsion was directed more externally compared to the healthy side. The difference in humeral torsion between the affected and non-affected sides was significant (p<0.05) in both groups. Differences in humeral torsion between the affected and non-affected sides in children with hemiplegic cerebral palsy were significantly increased (p<0.00001) compared to differences in humeral torsion between left and right arms in healthy children. A correlation with the level of severity of hemiplegic cerebral palsy was observed but there was no correlation with age. Children and adolescents with external torsional deformity had a smaller range of rotation, a larger muscle force deficit of the affected upper extremity and did less sport using the affected arm than children and adolescents with internal torsional deformity.
CONCLUSION: Humeral torsion deformity in children and adolescents with hemiplegic cerebral palsy was proven to exist in addition to the already well known difference in torsion of the lower extremities. Analogous to increased activity of external or internal rotator muscles codetermined by the palsy, increased external or internal humeral torsion occurs. External torsion deformity was associated with a smaller range of motion and seemed to have a greater importance for routine daily activities (e.g. muscle force, sports ability) than internal torsion deformity.