Philip Rowe

What is balance

Balance is a term frequently used by health professionals working in a wide variety of clinical specialities. There is no universally accepted definition of human balance, or related terms. This article identifies mechanical definitions of balance and introduces clinical definitions of balance and postural control. Postural control is defined as the act of maintaining, achieving or restoring a state of balance during any posture or activity. Postural control strategies may be either predictive or reactive, and may involve either a fixed-support or a change-in-support response. Clinical tests of balance assess different components of balance ability. Health professionals should select clinical assessments based on a sound knowledge and understanding of the classification of balance and postural control strategies.

Knee joint kinematics in gait and other functional activities measured using flexible electrogoniometry: how much knee motion is sufficient for normal daily life?

The knee joint kinematics of a group (n=20) of elderly normal subjects (mean age=67 years) were investigated using flexible electrogoniometry. The flexion-extension angle of the knee was recorded during a range of functional activities performed as part of a circuit in and around the hospital. The functions analysed including gait, walking on slopes, stair negotiation, the use of standard and low chairs and a bath. The data were used to produce the pattern of joint angulation against the percentage of the cycle for each individual conducting each activity. Further the maximum and minimum knee joint angles and the excursion of the joint during the cycle were identified. The results indicate gait and slopes require less than 90 degrees of knee flexion, stairs and chairs 90-120 degrees of flexion and a bath approximately 135 degrees of flexion. The data suggests that 110 degrees of flexion would seem a suitable goal for the rehabilitation of motion in the knee. It is concluded that flexible electrogoniometry is a suitable and practical method for evaluating knee motion during a range of functional activities.

A prospective randomised double-blind study of functional outcome and range of flexion following total knee replacement with the NexGen standard and high flexion components

Modifications in the design of knee replacements have been proposed in order to maximise flexion. We performed a prospective double-blind randomised controlled trial to compare the functional outcome, including maximum knee flexion, in patients receiving either a standard or a high flexion version of the NexGen legacy posterior stabilised total knee replacement. A total of 56 patients, half of whom received each design, were assessed pre-operatively and at one year after operation using knee scores and analysis of range of movement using electrogoniometry. For both implant designs there was a significant improvement in the function component of the knee scores (p < 0.001) and the maximum range of flexion when walking on the level, ascending and descending a slope or stairs (all p < 0.001), squatting (p = 0.020) and stepping into a bath (p = 0.024). There was no significant difference in outcome, including the maximum knee flexion, between patients receiving the standard and high flexion designs of this implant.

Knee joint functional range of movement prior to and following total knee arthroplasty measured using flexible electrogoniometry

The functional ranges of movement of the knee were investigated in a group of patients with knee osteoarthritis (n = 42, mean age 70 years) before, 4 months and at 18-24 months after total knee arthroplasty and then compared with age matched normal subjects (n = 20, mean age 67 years). Flexible electrogoniometry was used to record the maximum flexion-extension angle, the minimum flexion-extension angle and flexion-extension excursions of both knees during eleven functional activities along with the active and passive knee joint range of motion measured using a manual goniometer. Over the eleven functional activities the patients pre-operatively exhibited 28% less knee joint excursion than normal age matched subjects. By 18-24 months following total knee arthroplasty only 2% of this deficit was recovered. Statistically this recovery was only significant in level walking, slope ascent and slope descent. A greater range of movement was measured in a non-weight bearing position than was used in weight bearing functional activity. It is concluded that total knee arthroplasty gives rise to little improvement in knee motion during functional activities and that functional range of movement of the knee remains limited when compared to normal knee function for a minimum of 18 months following operation.

The use of therapeutic electrical stimulation in the treatment of hemiplegic cerebral palsy

The effect of electrical stimulation of the anterior tibial muscles of children with hemiplegic cerebral palsy was studied. 10 children received electrical stimulation, applied by their parents daily for an hour for 35 days; they were compared with 10 matched controls. Active and passive ranges of movement of the ankle, and knee and ankle motion during walking were measured before and after therapy using electrogoniometers. The results showed a significant increase in passive range of movement among children receiving electrical stimulation. Gait analysis of knee and ankle motion showed little change.

Validation of Flexible Electrogoniometry as a Measure of Joint Kinematics

Summary Background and Purpose The Biometrics Flexible electrogoniometer has the potential to allow physiotherapists to record the motion of joints during dynamic functional activities. In order to make full and appropriate use of this device it is necessary to comprehend the design, attachment and measurement properties of this instrument. Methods The measurement properties of the Biometrics flexible electrogoniometer were investigated using a series of controlled experiments. The in vivo performance of the device was evaluated by comparing the results of the electrogoniometer to those from a TV motion analysis system while measuring knee movement during gait in five normal subjects. Results The results of these studies indicate that the electrogoniometers are stable, precise, accurate and repeatable in performance. Little variation exists between electrogoniometers or between the performance of an electrogoniometer at different times, on different days or in different environmental conditions. Small hysteretic effects and inaccuracies are present in the devices but these are of the order of 1 or 2 degrees. The system is not affected by environmental pollutants such as heat, electrical interference, convection currents or noise and therefore can be used in a variety of hospital settings. The device is however affected by abduction/adduction angle with angles of 40° or more giving substantial errors when associated with simultaneous flexion or extension. Conclusions The electrogoniometer should be attached firmly and securely across the joint in an essentially planar configuration. Provided care is taken to handle and mount the electrogoniometers appropriately they appear to record knee movement faithfully and accurately and the system is capable of giving valid and meaningful clinical data.

Proprioception and muscle torque deficits in children with hypermobility syndrome

OBJECTIVES Sensorimotor deficits such as impaired joint proprioception and muscle weakness have been found in association with hypermobility syndrome (HMS) in adults. HMS is more common in children than adults, yet such deficits have not been adequately investigated in paediatric populations. It is therefore uncertain as to what sensorimotor deficits are present in children with HMS. This study investigated knee joint proprioception and muscle torque in healthy children and those with HMS. METHODS Thirty-seven healthy children (mean age +/- s.d. = 11.5 +/- 2.6 yrs) and 29 children with HMS (mean age +/- s.d. = 11.9 +/- 1.8 yrs) participated in this study. Knee joint kinaesthesia (JK) and joint position sense (JPS) were measured, with the absolute angular error (AAE) calculated as the absolute difference between the target and perceived angles. Knee extensor and flexor muscle torque was assessed and normalized to body mass. Mann-Whitney U-tests were performed to compare JK, JPS and muscle torque between the two groups. RESULTS Children with HMS had significantly poorer JK and JPS compared with the controls (both P < 0.001). Knee extensor and flexor muscle torque was also significantly reduced (both P < 0.001) in children with HMS compared with their healthy counterparts. CONCLUSIONS The findings of this study demonstrated that knee joint proprioception was impaired in children with HMS. They also had weaker knee extensor and flexor muscles than healthy controls. Clinicians should be aware of these identified deficits in children with HMS, and a programme of proprioceptive training and muscle strengthening may be indicated.

Physical activity and quality of life: A study of a lower-limb amputee population:

This cross-sectional descriptive study was initiated to investigate the relationship between physical activity and perceived quality of life in a lower-limb amputee population. The objective was to show which aspects of physical activity were most strongly linked to quality-of-life factors in this special patient group. The outcome measurements were two questionnaires: a section of the Trinity Amputation and Prosthetic Experience Scales (TAPES) and the World Health Organization Quality-of-Life Scale (WHOQOL-Bref). The former measures activity restriction and has Athletic, Functional, and Social subscales. The latter includes Physical, Psychological, Social, and Environmental domains, and measures the individuals perception of their quality of life. The two questionnaires were sent by post to 75 male and female participants with either trans-tibial or trans-femoral amputation who were receiving prosthetic care from a Glasgow-based rehabilitation and mobility centre and who met the inclusion criteria. All participants were over 18 years of age (mean age 66 years). In total, 25 participants returned the questionnaires—a response rate of 33%. According to analysis, 8 of the 12 relationships found were statistically significant. There was a very strong correlation between scores on the social elements of each questionnaire. The correlations between scores on the functional and athletic elements of the TAPES questionnaire and scores on the social element of the WHOQOL-Bref questionnaire were less strong. Our findings support the need for greater acknowledgement by healthcare professionals involved in the care of those with amputation about the importance of the patients social relationships with friends and family. Education about the importance of increasing and maintaining a level of physical activity conducive to health benefits should be implemented within a supportive sociable environment for the patient with lower-limb amputation.

Affordable clinical gait analysis: an assessment of the marker tracking accuracy of a new low-cost optical 3D motion analysis system

BACKGROUND 3D motion analysis represents a method of collecting objective, accurate and repeatable gait data, however the high cost of equipment inhibits its widespread use in routine clinical practice. OBJECTIVE To determine the marker tracking accuracy of a new low-cost optical 3D motion analysis system. DESIGN Comparative between-system study. SETTING Clinical motion analysis laboratories. METHODS A rigid cluster of four reflective markers was used to compare a low-cost Optitrack 3D motion analysis system against two more expensive systems (Vicon 612 and Vicon MX). Accuracy was measured by comparing the mean vector magnitudes (between each combination of markers) for each system, and reliability was measured through the coefficients of variation (CV). Gaps in the marker trajectories, which are considered undesirable, were also counted. RESULTS In terms of accuracy, the largest disagreement between mean vector magnitudes for Optitrack and Vicon MX was 2.2%. The largest disagreement between Vicon 612 and Vicon MX was 2.1%. Regarding reliability, the mean CV was lowest in Vicon MX (0.3%) and similar in the Vicon 612 (2.5%) and Optitrack (2.3%) systems. The number of trajectory gaps for the Vicon MX, Vicon 612 and Optitrack systems were; zero, six and 11 respectively. CONCLUSIONS The Optitrack system provides a low-cost 3D motion analysis system that can offer marker tracking accuracy and reliability which is comparable with an older and still widely used system (Vicon 612). Further development work is required before Optitrack can be used for full 3D gait analysis by physiotherapists and other health professionals.

Movement of the knee in osteoarthritis: THE USE OF ELECTROGONIOMETRY TO ASSESS FUNCTION

We used electrogoniometers to measure the range of movement (ROM) of the knee during various activities, comparing 50 patients with osteoarthritis of the knee (OA) with 20 healthy age- and sex-matched subjects. The minimum and maximum joint angles and the ranges of excursion of the patient and control groups were tested for significant differences, using an unrelated Students t-test with pooled variance. Knee flexion in patients with OA was significantly reduced during all activities (p < 0.05), but differences in knee extension were not significant except when patients negotiated stairs. We believe that this reduction in ROM is caused by inhibition due to pain when load-bearing. Static non-load-bearing measurements of the ROM poorly reflected the functional ROM, with a coefficient of determination (r2) of 0.59 in the patient group and 0.60 in the control group. Electrogoniometry of the ROM of the knee provides a reliable, accurate and objective measurement of knee function.