Foot Drop: Categorisation and Analysis of Corrective Measures

Foot drop is a condition that can have a large impact on quality of life due to its effect on gait and mobility. Foot drop is the condition where dorsiflexion (upward motion) is reduced significantly resulting in a very distinct "slap gait". There are many causes for this condition (such as stroke or nerve disorders), so the treatment of foot drop is varied. Some of the main treatments for foot drop include Functional Electrical Stimulation (FES), Ankle Foot Orthosis (AFO) and surgical interventions. This project is concerned with analysing gait in individuals with foot drop using Vicon motion capture hardware and software and EMG signal recording using Delsys software. Further information may be obtained using accelerometers and magnetometers on some form of sock, however anything designed will face challenges in being certified for use. As this project is in conjunction with the NHS (Freeman Hospital) there will be access to the data from the gait assessment service.

The motion capture equipment used with Vicon relies on several cameras set up at different angles to obtain a full picture of the space. These cameras then pick up infrared markers placed on key points (e.g. knees, ankles) using the Helen Hayes/Oxford foot model. During a walking trial many parameters can be measured using this set up, including gait speeds and key foot and ankle angles. Additional data can be calculated as a result of the angles and speeds recorded. The EMG recordings can be done in tandem with the motion capture assessments using surface electrodes.

This data will then be used to categorise the condition and compare before and after treatment. All data will be observed and compared, and any differences will be noted. There will then be an attempt to collate this data to use to predict the success outcomes of specific treatments with an individual with a particular categorisation. This will be done using a statistical analysis (using the R programming language), the specifics of this are dependent on the number of participants acquired. The link with the NHS will be very important for this research, as they have access to a large amount of pre and post treatment data. Also, the opportunity to have access to medical knowledge and experience would be very useful in making sense of particular patterns and adding more context to the data.

The final stage of the project involves design of a treatment strategy taking into account the data already collected and identifying any issues with current treatment. This project aims to not only provide a novel insight into the analysis of foot drop from a mechanical/electrical perspective but also help to inform the protocol used in a clinical setting. The foot and ankle services in the Freeman Hospital will implement some of the protocol produced in order to produce useful reports for foot drop patients.