Effects of ladder parameters on asymmetric patterns of force exertion during below-knee amputees climbing ladders

Abstract

Different from walking, ladder climbing requires four-limb coordination and more energy exertion for below-knee amputees (BKAs). We hypothesized that functional deficiency of a disabled limb shall be compensated by the other three intact limbs, showing an asymmetry pattern among limbs. Hand and foot forces of six below-knee amputees and six able-bodied people were collected. Hand, foot and hand/foot sum force variances between groups (non-BKA, intact side and prosthetic side) were carefully examined. Our hypothesis was validated that there is asymmetry between prosthetic and intact side. Results further showed that the ipsilateral hand of the prosthetic leg is stronger than the hand on the intact side, compensating weakness of the prosthetic leg. Effects of ladder rung separations and ladder slant on asymmetric force distribution of BKAs were evaluated, indicating that rung separation has a more significant interactive effect on hand/foot force of BKAs than ladder slant.

Keywords:

• ladder climbing
• hand force
• foot force
• below-knee amputee
• asymmetry

Acknowledgements

The authors express sincere thanks to the administrative staff of China Disability Association, who accompanied them in the two-year investigations. The authors’ sincere appreciation shall also be given to the faculty of Sport Science Department in Wuhan Sport University. Last but not least, many thanks shall be given to Foxconn Technology Group and Hubei Huitian Rubber Company for their devotion to applications of our guidelines.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This project was supported by China National Science Foundation [grant number 71301057] and the Foxconn Fund on Handicapped Job Placement. Field investigations and experiment studies were supported by staff of China Disability Association and the faculty of Sport Science Department in Wuhan Sport University. Applications of the study were supported by Foxconn Technology Group and Hubei Huitian Rubber Company.