Abstract: ObjectiveTo study the best estimating method of measuring length of crutches.Methods99 healthy student acted as volunteers for the test and the height of crutches was estimated with error margin of linear regression.ResultsThe error value of subtracting 41cm from the height of the subject was 7.071, and the error value of tip of Olecranon to the 3rd fingertip was 9.165.Conclusion The value of subtracting 41cm from the height of subject is more reliable in estimating the ideal length of crutches. The value of tip of Olecranon to the 3rd fingertip is ideal for determining fitting of the handgrip.

Key words: crutch, length, estimation, error margin, energy depletion