Neil Messenger

Kinematics of cycling in relation to anterior knee pain and patellar tendinitis

The coronal and sagittal plane leg movements of 24 experienced male cyclists were assessed using video analysis while cycling on a Kingcycle windload simulator. The cyclists were grouped into those with a history of injury and an asymptomatic group on the basis of self-reported injury status. The ages, cycling experience, competition distances and competition speeds of the two groups were compared using Students t-test. No significant differences (P <0.05) were found for any of these variables. The maximum and minimum shank adduction, shank adduction velocities, knee flexion and ankle dorsiflexion values were also compared using Students t-test. Significant differences were found at the point of maximum adduction (1.9°; P = 0.019) and minimum dorsiflexion (4.9°; P = 0.014). These differences indicated more dorsiflexion and greater abduction on the part of the symptomatic cyclists, supporting previous research that found that cyclists with a history of injury differ from those without a history of injury in the coronal plane leg movement patterns they adopt. Also, the most extreme medial position of the knee relative to the ankle occurred during knee extension. This supports the potential injury mechanism proposed by Francis (1986), which had previously only been examined using coronal plane kinematics.

Energetics of paraplegic walking

A group of 35 paraplegic subjects using reciprocating walking orthoses have been examined in order to gain an insight into the potential functional benefits of using such devices. Measurements have been made of walking speeds and of the energy costs of ambulation using an established technique based on heart rate recordings. It was found that orthotically aided walking for paraplegics was slow and energy costly compared with both normal walking and wheelchair propulsion and, as it additionally requires the use of a walking aid in both hands, cannot be considered to confer the functional benefits frequently claimed for it. Nevertheless, the majority of the subjects studied liked their orthosis and did well in it, with many subjectively reporting improvements in mobility and independence.

The Measurement of Gait

An individual’s walking pattern represents his or her particular solution to the problem of getting from A to B with the minimum expenditure of energy. It is generated through the precise and complex interaction of the many elements of the locomotor system, and under normal circumstances represents a highly efficient form of movement. However, any disorder or disruption of any constituent part of the system will have a deleterious effect on the resulting gait, causing deviations from the normal optimum pattern and making gait less efficient. The restoration of an optimum walking pattern is often a central part of the rehabilitation process. This clearly requires judgements to be made on a patient’s gait pattern at intervals during rehabilitation in order to assess the outcome of the treatment to date and effectively plan the future regime. To do this, clinicians must normally rely on observation of the patient’s gait pattern using

The Role of Gait Analysis in Clinical Medicine: A Survey of UK Centres

This paper reports the results of a survey carried out to assess the clinical usage currently being made of gait analysis facilities within the UK.Thirty-five centres were circulated with a questionnaire which requested information under four main headings: (i) equipment, (ii) research projects, (iii) clinical service commitments, and (iv) subjective views of the ultimate clinical value of the service. Of the 25 completed questionnaires returned, 16 were suitable for inclusion in the final analysis of data.The survey provided useful data on the equipment and facilities available in each centre together with details of the service available to prospective referring clinicians. Ten centres were considered as being currently involved in some clinical work, with six of these being routinely involved.The respondents generally felt that gait analysis techniques have a clinical context, if not yet routinely, but the numbers of referrals to the centres is still quite small. A number of areas worthy of further wor...

Effects of ambulation on the blood flow in paralysed limbs

Non-invasive transcutaneous blood gas monitoring techniques have been used as indicators of the effect of standing exercise on circulation in paraplegic subjects. Oxygen (tPO2) and carbon dioxide (tPCO2) electrodes were positioned on the chests and legs of a group of normal control subjects and a group of paraplegic subjects in both rested sitting and post-ambulatory standing. It has been shown that, with one possible exception, there is no significant difference in the transcutaneous blood gas partial pressures of O2 and CO2, and thus, by inference, in the circulation of paraplegics when either sitting or standing.

Sequential therapy of anti-Nogo-A antibody treatment and treadmill training leads to cumulative improvements after spinal cord injury in rats

ABSTRACT Intense training is the most clinically successful treatment modality following incomplete spinal cord injuries (SCIs). With the advent of plasticity enhancing treatments, understanding how treatments might interact when delivered in combination becomes critical. Here, we investigated a rational approach to sequentially combine treadmill locomotor training with antibody mediated suppression of the fiber growth inhibitory protein Nogo‐A. Following a large but incomplete thoracic lesion, rats were immediately treated with either anti‐Nogo‐A or control antibody (2 weeks) and then either left untrained or step‐trained starting 3 weeks after injury for 8 weeks. It was found that sequentially combined therapy improved step consistency and reduced toe dragging and climbing errors, as seen with training and anti‐Nogo‐A individually. Animals with sequential therapy also adopted a more parallel paw position during bipedal walking and showed greater overall quadrupedal locomotor recovery than individual treatments. Histologically, sequential therapy induced the greatest corticospinal tract sprouting caudally into the lumbar region and increased the number of serotonergic synapses onto lumbar motoneurons. Increased primary afferent sprouting and synapse formation onto lumbar motoneurons observed with anti‐Nogo‐A antibody were reduced by training. Animals with sequential therapy also showed the highest reduction of lumbar interneuronal activity associated with walking (c‐fos expression). No treatment effects for thermal nociception, mechanical allodynia, or lesion volume were observed. The results demonstrate that sequential administration of anti‐Nogo‐A antibody followed in time with intensive locomotor training leads to superior recovery of lost locomotor functions, which is probably mediated by changes in the interaction between descending sprouting and local segmental networks after SCI. HIGHLIGHTSSequential combination of anti‐Nogo‐A antibody and locomotor training enhanced recovery after incomplete spinal cord injury.Only the combination group showed sprouting of corticospinal tract fibers into lumbar segments.Locomotor training significantly reduced sprouting of Ia afferents into spinal cord compared to anti‐Nogo‐A antibody group.No changes in mechanical allodynia or thermal nociception were detected in any group.

Virtual prototyping of a semi-active transfemoral prosthetic leg.

This article presents a virtual prototyping study of a semi-active lower limb prosthesis to improve the functionality of an amputee during prosthesis–environment interaction for level ground walking. Articulated ankle–foot prosthesis and a single-axis semi-active prosthetic knee with active and passive operating modes were considered. Data for level ground walking were collected using a photogrammetric method in order to develop a base-line simulation model and with the hip kinematics input to verify the proposed design. The simulated results show that the semi-active lower limb prosthesis is able to move efficiently in passive mode, and the activation time of the knee actuator can be reduced by approximately 50%. Therefore, this semi-active system has the potential to reduce the energy consumption of the actuators required during level ground walking and requires less compensation from the amputee due to lower deviation of the vertical excursion of body centre of mass.

Moving the human machine: understanding the mechanical characteristics of normal human walking

Analysing the motion of the human body provides a means of demonstrating the practical implications of a number of fundamental mechanical concepts. In this discussion of the apparently simple action of walking, the concepts of kinetic and potential energy and energy transfer, of Newtons second law and the impulse-momentum relationship and of basic levers and equilibrium are used to explain why individuals walk in almost identical ways.

Tennis footwear: An investigation of impact characteristics

Tennis is promoted as an excellent source of physical activity for individuals of all ages and abilities due to the fitness and psychosocial benefits associated with play. For elite players achieving world class status is the ultimate performance goal. The pursuit of excellence and mass participation in tennis has lead to great investment in equipment from both a performance enhancement and an injury prevention perspective. Rapid, multi-directional movement will typically increase both the load and the rate of loading experienced by an athlete. The consequence of this on the musculoskeletal system is to increase the likelihood of sustaining an injury depicted by an acute or chronic mechanism (Luethi et al. 1986). Footwear is considered a sensible strategy in injury prevention specifically for the lower limbs due to its potential ability to attenuate impact forces via cushioning. Confounding the potential of injury further is the hardness of the playing surfaces which is associated with an increase in injury risk (Strauss 2003). These considerations are particularly applicable for tennis as the game is played on difference court surfaces with varying degrees of hardness, ranging from the acrylic ‘hard’ to the grass ‘soft’ courts. Currently there is limited understanding of the interaction between the player, the surface and the role footwear has in injury prevention. The aims of this study are two-fold: (1) to measure the impact properties of a variety of tennis footwear independently of human interaction; and (2) to evaluate the impact characteristics of the shoe-surface interface.

Biomechanical analysis of walking gait when simulating the use of an Ilizarov external fixator

The Ilizarov frame is an external fixation device, primarily used for the treatment of complex fractures. The authors postulate that the size and weight of the frame may lead to biomechanical adaptations to gait, independent to any injury. Temporospatial characteristics, kinetics and kinematics were assessed when simulating the use of an Ilizarov frame. Fifteen healthy participants performed walking trials, with and without the simulated frame. Significant changes to temporospatial characteristics were identified, with a decreased mean walking speed (with: 1.24 m s–1; without: 1.29 m s–1) and increased mean step width (with: 0.14 m; without: 0.11 m). The push-off phase of gait differed significantly between test conditions with mean increases in ankle dorsiflexion angles (with: 90.4°; without: 89.0°) and extension moments (proportional to body weight or P BWT) at the knee and ankle (knee with: 0.8 P BWT·m; without: 0.7 P BWT·m; ankle with: 1.6 P BWT·m; without: 1.6 P BWT·m). Although changes were small and likely to be clinically insignificant, the size and weight of the frame led to adaptations which may be magnified for patient groups with associated injury and pain at the lower limb. Results provide an argument for the potential redesign of the frame.