Application of a digital head-posture measuring system in children.

PURPOSE: To report the repeatability of a digital head-posture measuring system when used to record anomalous head postures in children.

DESIGN

Prospective study and clinical laboratory investigation.

METHODS

Using a digital head-posture measuring system, we measured 36 different anomalous head postures in 27 children with infantile nystagmus syndrome. Repeatability values and 95% limits of repeatability of measurements were generated for anomalous head postures.

RESULTS

Among the 27 children, 3 had 2 head postures (right and left head turns) in 2 different directions; 6 had 2-dimensional head postures that were considered 2 different head postures; and 18 had a 1-dimensional head posture. There were 5 chin-up or chin-down postures, 23 head-turn postures, and 8 head-tilt postures in a total of 36 anomalous head postures. The repeatability value for all anomalous head postures was less than 10 degrees. Ninety-five percent limits of repeatability yielded ranges of less than 10 degrees for all anomalous head postures.

CONCLUSIONS

The digital head-posture measuring system is a valid and reliable device for measuring 3-dimensional head postures in children with nystagmus.