A smart cane with vibrotactile biofeedback improves cane loading for people with knee osteoarthritis

Abstract

Nine million adults have symptomatic knee osteoarthritis (OA) in the U.S. and almost half of those people have a walking aid such as a cane. Proper cane loading (e.g. 15% body weight [BW]) can reduce knee loading and may slow OA progression. The purpose of this study was to investigate the efficacy of a novel smart cane with vibrotactile biofeedback that aims to facilitate increased cane loading. Ten subjects with knee OA performed a 50 m hallway walk test under four conditions: 1) naïve, 2) conventional cane with verbal instruction, 3) smart cane, and 4) conventional cane post smart cane. The cane load (% BW; mean ± 1 standard deviation) for the four conditions was 9.0 ± 1.9 (naïve), 12.7 ± 2.6 (conventional cane), 17.6 ± 2.4 (smart cane), and 15.6 ±3.1 (conventional cane post smart cane). These results indicate that the smart cane's vibrotactile biofeedback helped the users achieve the target cane loading of 15% BW or more as compared to naïve or verbal instruction alone. After using the smart cane, conventional cane loading was higher than the naïve and verbal instruction conditions demonstrating a potential smart cane training effect. Long term increased cane loading may reduce knee pain and improve joint function.

A cane-based low cost sensor to implement attention mechanisms in telecare robots

“…On-board sensors on most smart canes are located either on the handgrip [6], [14], shaft [15], [16], [17], [7], [14], [7] or tip [6], [15]. Placing sensors on the handgrip or tip may involve major cane modifications [6], [14].…”

“…The shaft allows more space to place the electronic. However, this approach may involve changes in the cane center of gravity and also, in its weight [16], [15], [7], [14]. Even in a best case scenario, any modification significantly affecting a walking aid requires an extensively validation and/or certification process.…”

“…2) Electronic design: There are different options to measure the load on the cane, both in handgrips and shafts [6], [14] [7]. The main drawback of most existing approaches is that they rely on relatively expensive electronic components, such as piezoelectric quartz force link with in-line amplifier (Kistler Instrument Corp., Novi, MI) [7] or array of force sensor (FSR 402, Interlink Electronics, USA) [6], reducing affordability for end-users. The main drawback of simpler, cheaper sensors is that their range is very limited, usually 10 Kg or less.…”

“…Changes in activity periods also provide valuable information on the person's condition. Cane sensors may provide information on two relevant health related parameters: weight bearing and gait trends [6], [7].…”

A Novel Walking Cane With Haptic Biofeedback Reduces Degenerative Loading in the Arthritic Knee

“…This is especially true for walking canes used for off-loading of an injured or disabled leg. While cane use may seem straight-forward, one of the most important aspects for knee OA patientsapplying enough load to the cane in order off-load the arthritic jointis patient-specific, and often underestimated [18], [19]. Failure to apply sufficient axial load to the walking cane, in turn, does little to relieve the arthritic leg of undue stress and symptomatic pain.…”