Objective gait analysis made (and continues to make) a significant contribution in improving the outcome of interventions of children with cerebral palsy (CP). The use of objective gait analysis and the change in surgical approach is a prime example of how technology and open, inquiring minds came to interact for the benefit of our patients.The University Hospital of Leuven (Pellenberg) has seen rapid developments in the area of clinical gait analysis since 1992, using a multidisciplinary approach.

For the past decade, the gait laboratory has been a centre for the evaluation of children and adults with gait problems. In today's competitive health care market, we cannot rely on traditional treatment theories without rigid research to prove them. Therefore, apart from the individual clinical gait evaluations, the gait laboratory has always been the heart of numerous research projects.The team of the gait analysis laboratory was honoured to receive the invitation of the ESMAC committee to organize the eleventh annual meeting in Leuven. We have the privilege of welcoming you to Leuven for the ESMAC gait courses and conference, for the week beginning September 16.HistoryThe first steps towards a clinical gait analysis laboratory at the University Hospital of Leuven were taken in 1992.

At that time, gait evaluations were performed using a set of normal video cameras and a four camera automatic video system synchronised with a forceplate. From these first evaluations, the use of objective gait analysis became more and more obvious and crucial in defining an optimal treatment plan for children and adults with spasticity.After a training session with the group under the direction of Prof. Gage at the Gillette Specialty Child Care Center in Minnesota, U.S.A in 1993, Dr.

Guy Molenaers, Paediatric orthopaedic surgeon of the University Hospital of Leuven, was convinced of the need for an up-to-date three dimensional gait lab, integrated within the multidisciplinary framework of the hospital. However, lack of both budget and space prevented an immediate update of the available gait lab facilities.Finally, in July 1996, the gait lab was upgraded with a Vicon 370 system, founded as a multidisciplinary service. This was the result of a joint effort of three departments within the University of Leuven: the department of paediatric orthopaedics under Prof. Fabry, rehabilitation, headed by Prof. Lysens, and the child neurology department led by Prof.

Casaer.The Vicon 370 system with five cameras was synchronised with two AMTI forceplates, four normal video-cameras and a 16 channel surface EMG system. A typical data collection at that time involved kinematic and kinetic data collection, sagittal, coronal and transverse plane split screen video, and bilateral surface EMG of the rectus femoris, vastus lateralis, medial and lateral hamstrings, tibialis anterior, gastrocnemius, soleus, and for some patients gluteus medius, or other surface muscles of the lower limb. The Vicon clinical manager was used to process the data.The current gait analysis laboratorySince September 2001, the three-dimensional lab has been advanced further by means of a Vicon 612 system with eight M-cameras, supported by three AMTI force plates and a 16 channel surface EMG system (K-Lab). For most routine gait analyses, the M-cameras are used at 120 Hz.

Gait data are now processed using Polygon, making use of the PluginGait marker set. Bodybuilder software is available for special model development. Clinical gait analysis is always combined with a thorough clinical examination, assessing ROM, spasticity and muscle force and selectivity.In young children (;4 years) gait analysis is limited to standardized video recording, because of a lack of sustained concentration.

The 2D video laboratory runs in parallel with the Vicon 3D lab. The 2D laboratory uses a standardized video protocol in order to characterize motor function, including walking, in young children and adults that do not meet the inclusion criteria for a 3D gait assessment.A video recording is taken in different planes, including a close-up of the foot. Apart from five normal video cameras, the 2D lab also includes a foot pressure system (RS-scan platform and in-shoe pressure measurement system) in order to study pressure distribution in patients with foot deformities. The 2D lab is also used for upper limb evaluation.

A standardized protocol for the evaluation of upper limb function has recently been developed and is used with an adopted clinical examination. A special trajectory in the 2D lab is used for energy measurements (Cosmed b4).Since the Vicon lab began in 1996, over 2500 full 3D gait assessments have been performed according to the established protocol. At present 15 full gait evaluations and between eight and ten video analyses are planned each week.

Full gait analysis in the 3D gait laboratory.Clinical applicationsFrom the start of the activities, the major field of interest was the evaluation of gait deviation associated with neuromuscular disorders (mainly children with CP, but also patients with spina bifida, Charcot-Marie Tooth, arthrogryposis). Other evaluated patient categories are tip-toe walkers, children with clubfeet and other lower limb deficiencies. Since 2000, adults are more often evaluated in the gait lab (adults with CP, stroke, craniocerebral trauma, incomplete paraplegia, post-polio gait difficulties, foot problems with total gait involvement and other lower limb deficiencies). The areas of application are continuously extending.

The use of gait analyses in our department serves several purposes:- First gait evaluation (preferably at a young age)- Follow-up gait evaluation (frequently throughout growing spurt)- Evaluation and tuning of ankle foot orthoses- Evaluation of assistive devices- Pre-intervention screening (orthopaedic surgery, selective dorsal rhizotomy, Botulinum toxin A treatment, intrathecal baclofen).- Post-intervention gait analysis to evaluate the individual treatment result and to evaluate the present treatment hypothesis.The multidisciplinary teamGait analysis results are discussed during multidisciplinary review meetings. As a result of this, recommendations for therapeutic interventions are formulated and communicated to referring doctors or physiotherapists. These can be a broad selection of either physiotherapy settings, orthoses, surgical procedures directed to elongation or transfer of soft-tissue or restoration of bone alignment, Botulinum toxin injections, selective dorsal rhizotomy, baclofen treatment (oral or intrathecal administration). For each of these interventions, a history exists within the University Hospital of Leuven.

The 2D gait laboratory.Initially the lab was equipped with a small team. The gait analysis data was collected and processed by one kinesiologist, and discussed within a team comprising a kinesiologist, a paediatric orthopaedic surgeon, a neuro-paediatrician and a paediatric rehabilitation doctor. The laboratory multidisciplinary team gradually expanded, co-ordinated by Dr. Guy Molenaers (paediatric orthopaedic surgeon, clinical director of the gait laboratory), by kinesiologist Kaat Desloovere (PhD in biomechanics, manager of the gait laboratory) and by Professor Roeland Lysens (department director of the rehabilitation division and of C.E.

R.M.). The gait laboratory is now a major part of C.E.R.

M. (Centre of Evaluation en Rehabilitation of Motor functions) of the University Hospital of Leuven.