Long-term effect of robot-assisted treadmill walking reduces freezing of gait in Parkinson’s disease patients: a pilot study

Abstract

Freezing of gait (FOG) is a common and disabling symptom in patients with advanced Parkinson’s disease (PD). Treatment options are often limited, since dopaminergic medication can either alleviate or aggravate FOG, and deep brain stimulation does not seem to suppress FOG as well as other PD symptoms [5]. In the last decade, physiotherapeutic studies moved into the focus of research. Two case studies found that repetitive robot-assisted treadmill training reduces FOG [4, 10], and in a randomized controlled trial robot-assisted gait training was superior to conventional physiotherapy on general walking performance in PD patients [6]. However, long-term effects of this potentially new training method are unknown so far. Based on previous studies, we hypothesised that robot-assisted treadmill training specifically reduces FOG by either increasing step length and/or decreasing step length variation, and that, similar to other physiotherapeutic training methods, this therapeutic effect declines over time after cessation of training. Three PD patients diagnosed according to the UK PDS Brain Bank Criteria with severe FOG participated in the study. All patients gave informed consent before study participation. The study was approved by the local ethics committee. Patients were trained by an experienced physiotherapist (FC) specialized in neurological rehabilitation. All patients received 10–12 training sessions of 30 min on a robot-assisted treadmill (Lokomat , Hocoma, Switzerland) in their regular medication ON. Robot-assisted treadmill walking includes treadmill walking combined with a certain degree of body weight support through assistance of mechanically driven robotic orthosis. A robotic exoskeleton attached to the patients’ legs shifts them passively through a stereotyped gait cycle over a treadmill with variable amounts of assistance. Walking parameters such as gait speed, leg movement assistance and body weight support can be adjusted individually. All patients received a piloting training session before the actual training started. We intended to use the same walking parameters for all three patients. All three patients reported comfortable training with a gait velocity of 1.5 km/h, fully assisted leg movements and a body weight support of 70 %. In the training session, body weight support was initially set at 100 % and was then gradually reduced to 70 % to familiarize patients with the walking device. Range of motion at the hip joint was set at 45 ; all other settings were kept according to the manufacturer’s specifications. On some occasions, training sessions had to be terminated due to exhaustion shortly before 30 min were Electronic supplementary material The online version of this article (doi:10.1007/s00415-012-6703-3) contains supplementary material, which is available to authorized users.