Assessment of forearm and plantar foot load in the elderly using a four-wheeled walker with armrest and the effect of armrest height

Chang-Yong Ko,* Sol-Bi Kim,* Hyuk-Jae Choi, Yunhee Chang, Sungjae Kang, Yoon Heo, Jeicheong Ryu, Gyoosuk Kim, Museong Mun Korea Orthopedics and Rehabilitation Research Center, Incheon, South Korea *These authors contributed equally to this work Background: Patients with hand and/or wrist pathology are recommended to have a four-wheeled walker with an arm rest (FWW-AR) rather than a standard walker or a standard four-wheeled walker (FWW). However, only a few quantitative studies have been performed to compare upper and lower extremity weight bearing. The aim of this study was to evaluate forearm and foot weight bearing using a FWW-AR and the effect of the armrest height.Methods: Eleven elderly women (mean age 80.1±5.3 years; mean height 148.5±4.0 cm; mean weight 51.2±9.0 kg) were enrolled. The subjects walked with an FWW-AR, with the elbow in either 90 degree (D90) or 130 degree (D130) flexion, for a distance of 10 m. Surface electromyographic signals were recorded for the upper, middle, and lower trapezius, anterior deltoid, and erector spinae muscles; walking velocity was measured with the subjects weight bearing on their feet and forearms while walking. Simultaneously, the maximum plantar and forearm loads during walking with an FWW-AR were measured.Results: The normalized foot plantar loads were lower at D90 than at D130, while the normalized forearm load was higher at D90 than at D130 (all P