Electrobasographic records, together with 7,000 feet of moving pictures, have been made of two women with 'normal' gait, with thirteen different pairs of shoes. Interpretation of the gait records has been supported by the analysis of moving pictures made at 64 exposures per second.
The electrobasographic records have revealed the presence or absence of stability of the feet of persons wearing shoes of known last design, heel height, and quality of material, workmanship, and construction. Pronation is revealed by diminution of weight-bearing time on the fifth metatarsal head. Improper fitting of shoes, producing discomfort, is not revealed in the electrobasographic record until after the subject is unable to compensate for the pain produced.
The fitting of shoes has been based upon foot length, width, and comfort in the shoe. Little attention has been given to depth. Evidence presented indicates that stability of the foot in the shoe is not related to these criteria of fit. The shoe must, therefore, be regarded as a potential cause of inequality of weight-bearing on the three respective points of each foot.
Records indicate that shoes must differ in design of the last and other physical characteristics, so that they may fit most women with comfort and provide stability for the feet under the influence of weight-bearing. Although new shoes of inferior quality of material and workmanship may be comfortable and provide stability, they are more predisposed to the loss of the latter essential characteristic with increasing use and poor care.
Evidence indicates that, although the size of shoe may be correct and the foot may be free from pain, instability and abnormality in weight-bearing may result from improper design of the last with relation to the feet in question. This fault cannot be corrected by quality of material and skill in shoe construction. The foundation is wrong.
Data justify the statement that even a heel two and seven-eighths inches high may be worn upon occasion without subjective discomfort or recordable indication of instability of the feet. Some feet are more unstable than others; therefore, a particular shoe may not provide equal stability for different individuals.
The final conclusion of this work is that all of the factors pertaining to the relation of the patient's shoes to electrobasographic records are under control.
(C) 1935 All Rights Reserved.The Journal of Bone and Joint Surgery, Inc.