A study on the measurement of wrist motion range using the iPhone 4 gyroscope application

Measuring the range of motion (ROM) of the wrist is an important physical examination conducted in the Department of Hand Surgery for the purpose of evaluation, diagnosis, prognosis, and treatment of patients. The most common method for performing this task is by using a universal goniometer.

This study was performed using 52 healthy participants to compare wrist ROM measurement using a universal goniometer and the iPhone 4 Gyroscope application. Participants did not have previous wrist illnesses and their measured values for wrist motion were compared in each direction.

Normal values for wrist ROM are 73 degrees of flexion, 71 degrees of extension, 19 degrees of radial deviation, 33 degrees of ulnar deviation, 140 degrees of supination, and 60 degrees of pronation.The average measurement values obtained using the goniometer were 74.2 (5.1) degrees for flexion, 71.1 (4.9) degrees for extension, 19.7 (3.0) degrees for radial deviation, 34.0 (3.7) degrees for ulnar deviation, 140.8 (5.6) degrees for supination, and 61.1 (4.7) degrees for pronation. The average measurement values obtained using the iPhone 4 Gyroscope application were 73.7 (5.5) degrees for flexion, 70.8 (5.1) degrees for extension, 19.5 (3.0) degrees for radial deviation, 33.7 (3.9) degrees for ulnar deviation, 140.4 (5.7) degrees for supination, and 60.8 (4.9) degrees for pronation. The differences between the measurement values by the Gyroscope application and average value were 0.7 degrees for flexion, -0.2 degrees for extension, 0.5 degrees for radial deviation, 0.7 degrees for ulnar deviation, 0.4 degrees for supination, and 0.8 degrees for pronation. The differences in average value were not statistically significant.

The authors introduced a new method of measuring the range of wrist motion using the iPhone 4 Gyroscope application that is simpler to use and can be performed by the patient outside a clinical setting.