Effect of a supervised hip flexor-stretching program on gait in healthy elders

Abstract

Fig. 1. Kinematic profiles of the lower limb joints in the sagittal plane (right limb in green, left limb in red). of various forms of dystonia, however they present some important drawbacks in terms of sensitivity and reproducibility [3] because they are based on kinematic parameters visually assessed by the clinician. Although quantitative gait analysis is largely used to study kinematic impairments in patients with upper motor neuron disease or Parkinson’s disease, it has not been used so far to assess the pathology or medication or DBS effects in dystonic syndromes. Our objective was to evaluate the influence of DBS on multifocal dystonia in terms of clinical and spatio-temporal and kinematic parameters of lower limb during gait. Methods: The patient, a 52 years old female, with polio exit, developed first symptoms of dystonia when she was 33. She arrived at the laboratory in the morning preoperatively (baseline) and 12 months following DBS surgery with the stimulator on. Burke-FahnMarsden Dystonia Rating Scale (BFMDRS) was used to assess the patient before each gait analysis session which consisted of at least 10 trials where the patient walked along an 8-m walkway at her preferred speed. Kinematics, spatial and temporal gait measurements were measured preoperatively and 12 months following surgery by means of 6 infrared cameras (VICON 460 Oxford Metrics) and 16 markers positioned according to the Plug-in-Gait protocol. The differences between pre and post DBS were analyzed nonparametrically by using the Wilcoxon Signed-Rank test. Level of significance was set to 0.05. Results: An overall improvement in gait performance at month 12 of follow-up is showed by the spatio-temporal parameters. In particular, the walking velocity of the patient significantly increased (p = 0.003) with respect to the baseline condition. The increase in walking velocity may be explained by the significant increase in stride length (p = 0.00012), while cadence is similar between pre and post surgery. An increased symmetry of gait and a reduced inter-trial variability after surgery were related with a reduction of the pelvic tilt (p < 0.05) and of the right knee flexion (p < 0.05), together with an increase of the left knee flexion (p < 0.05)