The effect of footwear adapted with a multi-curved rocker sole in conjunction with knee-ankle-foot orthoses on walking in poliomyelitis subjects: a pilot study

Abstract

Background: Knee-ankle-foot orthoses (KAFOs) are used by people with poliomyelitis to ambulate. Whist advances in orthotic knee joint designs for use in KAFOs such the provision of stance control capability have proven efficacy, little attention has been paid to shoe adaptations which may also improve gait.Aim: The aim of this study was to evaluate the alteration to the kinematics and temporal-spatial parameters of gait caused by the use of heel-to-toe rocker-soled footwear when ambulating with KAFOs.Method: Nine adults with a history of poliomyelitis who routinely wore KAFOs participated in the study. A heel-to-toe rocker sole was added to footwear and worn on the affected side. A three-dimensional motion capture system was used to quantify the resulting alteration to specific gait parameters.Results: Maximum hip joint extension was significantly increased (p = 0.011), and hip abduction and adduction were both significantly reduced (p = 0.011 and p = 0.007, respectively) when walking with the rocker sole. A significant increase in stride length (p = 0.035) was demonstrated but there were no significant increases in either walking speed or cadence.Conclusions: A heel-to-toe rocker sole adaptation may be useful for walking in patients with poliomyelitis who use KAFOs.Implications for RehabilitationThe poor functionality and difficulty in walking when using an orthotic device such as a KAFO which keeps the knee locked during ambulation, plus the significant energy required to walk, are complications of orthoses using.Little evidence exists regarding the biomechanical effect of walking with a KAFO incorporating fixed knee joints, in conjunction with rocker-soled footwear.The main aim of walking with a heel-to-toe rocker sole is to facilitate forward progression of the tibia when used with an AFO or KAFO or to provide easier walking for patients who have undergone an ankle arthrodesis.In this study, a rocker sole profile adaptation produced no significant alteration to hip joint flexion, but hip joint maximum extension was significantly increased in subjects suffering from poliomyelitis, and maximum hip adduction and abduction were both significantly reduced.The most significant alterations were seen in stride length, and although there was a significant increase in this parameter, there was no statistically significant increase in walking velocity or cadence.