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

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.