The effects of application of lateral wedge insoles on medial osteoarthritis of the knee.

Abstract

The lateral wedge insoles seem to improve the external moment of knee adduction in individuals with medial knee osteoarthritis. This thesis sought to study the biomechanical changes and the effectiveness of using this type of insoles. Five studies were carried out. Three studies (study II, IV and V), sought to understand the effects of this type of insoles on biomechanics and clinical results. Twenty-three healthy participants (study II) and thirty-eight participants with medial knee osteoarthritis were recruited (study III, IV and V). A three-dimensional motion capture system was used together with force platforms for data collection. A systematic review with meta-analysis (study I) suggests that higher wedges (> 9 degrees) are not more effective than lower wedges (≤ 9 degrees). A distinct study (study III), which analysed the participants' performance in the 30-second chair stand test, found that they did not present significant biomechanical differences during the test, between the most and least painful knee. Six lateral wedge insoles with slight variations (2 degrees) were tested. It was found that they induce immediate effects incrementally in the frontal plane of the foot and knee (study II and IV). On the other hand, the continuous use of personalized insoles by biomechanical analysis, for 12 weeks, was not effective in improving biomechanical and clinical outcomes, except in symptoms, when compared with a neutral insole (study V). The continuous use of this type of device needs more robust evidence to support its use in individuals with medial knee osteoarthritis.