Loads on the uprights of a knee-ankle-foot orthosis

K. A. Bernhardt, Kenton R Kaufman

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Background: Objective design criteria for orthotic components is lacking. This paucity of data results in prescription guidelines based on assumptions or practitioners' past experience, and the potential for incorrectly designed components. The purpose of this study was to directly measure loads on the knee joint of a knee-ankle-foot orthosis. Study design: Case series. Case Description and Methods: Three subjects who had been prescribed a knee-ankle-foot orthosis for quadriceps weakness underwent gait analysis and orthotic upright load data collection. A load sensor to measure the three force and three moment components was used in place of the lateral knee joint while the subjects walked in three knee flexion positions. Findings and Outcomes: Forces were highest in compression and moments were greatest in the sagittal plane. The kinetics did not increase solely with patient weight. There was substantial variability between subjects. Conclusions: This data will help guide orthotic component design and prescription guidelines. Knowledge of loading conditions will lead to more optimal orthotic intervention for patients and increased patient satisfaction. Clinical relevance: This study is one of the first to directly measure loads on the upright of a KAFO. These data provide objective targets for engineering design. The data from this small case series can also be used to establish guidelines for patient device selection.

Original languageEnglish (US)
Pages (from-to)106-112
Number of pages7
JournalProsthetics and Orthotics International
Volume35
Issue number1
DOIs
StatePublished - Mar 2011

Fingerprint

Foot Orthoses
Ankle
Knee
Guidelines
Knee Joint
Prescriptions
Patient Satisfaction
Gait
Patient Selection
Weights and Measures
Equipment and Supplies

Keywords

  • Gait analysis
  • Knee-ankle-foot orthosis
  • Upright loads

ASJC Scopus subject areas

  • Rehabilitation
  • Health Professions (miscellaneous)

Cite this

Loads on the uprights of a knee-ankle-foot orthosis. / Bernhardt, K. A.; Kaufman, Kenton R.

In: Prosthetics and Orthotics International, Vol. 35, No. 1, 03.2011, p. 106-112.

Research output: Contribution to journalArticle

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