A modified axillary crutch for lower limb amputees

Objectives: The standard axillary crutch is known to cause general discomfort to the user and crutch palsy. Aim of this pilot study is to compare a modified axillary crutch with the standard aluminum crutch. The following modifications were made in the new design (patent – LK/P/15/866). 1. A single pole design 2. Improved axillary and back support 3. Shock absorbing mechanism 4. Adjustable hand grip Methods: Twenty normal subjects were used initially to ensure the safety and 20 amputees were later assessed. Both groups were studied before and after walking a distance of 50 meters using the standard and the modified crutch. Each subject was assessed three times on each crutch and the mean values were taken. The energy expenditure index (EEI) was calculated for each subject. The stability and comfort were assessed using a pre tested, close ended, self-administered questionnaire. Results: Twenty normal subjects {median age 23years (22-25); M: F 7:3)}, showed a significant reduction of heart rate (standard v modified, 11: 5, p=0.00) and EEI (standard v modified, 5.84: 2.39, p=0.00). Mean increase in velocity (standard v modified, 2.17:2.11, p= 0.58) was not significantly high. Twenty amputees {median age 63 years (35-90); M: F 5:1; AK: BK; 6:14; median duration of crutch use 6 months} showed a significant reduction of heart rate (standard v modified, 20: 14, p=0.00) and EEI (standard v modified, 10.59: 6.89, p=0.01), and an increase in velocity (standard v modified, 1.94: 2.11, p=0.00). Stability of the modified crutch was reported to be equivalent to the standard crutch by the majority in both groups {healthy volunteers; 14(70%), amputees; 13(65%)}. Comfort was considered to be better in the modified crutch by the majority {healthy volunteers; 15(75%), amputees; 12(60%)}. Conclusions: The modification reduces energy consumption during locomotion, provides more comfort with an equal level of stability compared to the standard. Introduction Crutches have not changed significantly during their 5,000 years of use (1). There are many reasons physiological and psychological why it is good to stand and walk rather than sit and have wheeled mobility (2-4). Crutches improve the quality of life of lower limb amputees. Traditional crutch designs are known to cause discomfort and complications such as crutch palsy due to the implied stress on the axilla (brachial plexus). Furthermore the user has to spend a considerable amount of extra energy for locomotion when compared to a normal individual. The purpose of this study was to test energy efficiency and the level of comfort provided by a modified axillary crutch compared with the standard aluminum crutch. Modifications made (patent – LK/P/15/866). 1. Improved axillary support with back support The axillary pad was ergonomically designed to fit the axillary curvature and increase the area of weight distribution. The extension of the axillary pad posterosuperiorly supports the back and maintains better stability while walking and in the stationary position.