Functional gait analysis of trans-femoral amputees using two different single-axis prosthetic knees with hydraulic swing-phase control: Kinematic and kinetic comparison of two prosthetic knees.

This paper reports a comparison of the gait patterns of trans-femoral amputees using a single-axis prosthetic knee that coordinates ankle and knee flexions (Proteor's Hydracadence system) with the gait patterns of patients using other knee joints without a knee-ankle link and the gait patterns of individuals with normal gait. The two patient groups were composed of 11 male trans-femoral amputees: six patients had the Hydracadence joint (Group 1) and five patients had other prosthetic knees (Group 2). The reference group was made up of 23 normal volunteers (Group 3). In this work, trunk, hip, knee, and ankle 3-D motion was assessed using the VICON system. Kinetic data were collected by two AMTI force plates, and the knee moment was calculated via the 3-D equilibrium equations. An original questionnaire was used to assess the participants' activity level and clinical background. The results reveal that, during stance, all knee types guaranteed security. After heel strike, the plantar flexion of the ankle enabled by the Hydracadence prosthesis seems to increase stability. During swing phase, hip and knee sagittal motion was nearly the same in both Group 1 and Group 2. By contrast, hallux and sole vertical positions were significantly higher in Group 1 than in Group 2; thus, it seems the link between the ankle joint and the knee joint makes foot clearance easier. No alteration of the lateral bending of the trunk was observed. The protocol proposed in this paper allows a functional comparison between prosthetic components by combining clinical data with objective 3-D kinematic and kinetic information. It might help to determine which prosthetic knees are best for a specific patient.

A functional evaluation of prosthetic foot kinematics during lower-limb amputee gait.

This paper reports on a functional evaluation of prosthetic feet based on gait analysis. The aim is to analyse prosthetic feet behaviour under loads applied during gait in order to quantify user benefits for each foot. Ten traumatic amputees (six trans-tibial and four trans-femoral) were tested using their own prosthetic foot. An original protocol is presented to calculate the forefoot kinematics together with the overall body kinematics and ground reaction forces during gait. In this work, sagittal motion of the prosthetic ankle and the forefoot, time-distance parameters and ground reaction forces were examined. It is shown that an analysis of not only trans-tibial but also trans-femoral amputees provides an insight in the performance of prosthetic feet. Symmetry and prosthetic propulsive force were proved to be mainly dependant on amputation level. In contrast, the flexion of the prosthetic forefoot and several time-distance parameters are highly influenced by foot design. Correlations show influential of foot and ankle kinematics on other parameters. These results suggest that prosthetic foot efficiency depends simultaneously on foot design and gait style. The evaluation, proposed in this article, associated to clinical examination should help to achieve the best prosthetic foot match to a patient.

[Evolution in prostheses for sprinters with lower-limb amputation]. / Evolution des prothèses des sprinters amputés de membre inférieur.

For about 15 years, technical advances in prosthetic treatment have been the main factor in the increased performance of athletes with lower-limb amputation. For trans-tibial amputation, the prosthesis for sprinting is composed of a gel liner and a socket joined by a locking or virtual vacuum liner. Because of these dynamic properties, the carbon prosthetic foot equipped with tacks ensures outstanding performance. For trans-femoral amputation, a hydraulic swing and a stance control unit are added to the same prosthesis. In comparison with the able-bodied runner, athletes with amputation have smaller loading times in the prosthetic limb and larger ones in the sound limb. The length of the energy-storing prosthetic foot is determined by the "up-on-the-toes" running gait. The sprinting gait with trans-tibial amputation is almost symmetrical. The hip extensor effort is the main compensation of propulsion reduction with lower-limb amputation. With trans-femoral amputation, the lack of knee increases the asymmetry. The total prosthetic knee extension (early in late-swing phase and lasting during total stance phase) compensates with extension of both hips, especially the opposite one. The amputation and sound limb load transfer with lumbar hyperlordosis concern the pelvis, trunk and shoulders. Because of athletes with amputation, research in prosthetic treatment has progressed. The development of orthotics and prostheses for such athletes has benefited non-athletes with amputation.

[Evaluation of a public health measure for the amelioration of birth safety in Martinique: 1977-1984]. / Evaluation d'une action de santé publique pour l'amélioration de la sécurité à la naissance en Martinique: 1977-1984.

A public health programme was instituted on the island of Martinique (in the Carribean archipelago) between 1977 and 1984. Its aim was to reduce the perinatal death rate in Martinique which was 25.7 per thousand in 1977 to the level found in France in the same year, namely 14 per thousand. The measures taken to improve the safety of deliveries included closing small maternity homes and improving the hospitals both public and private. The chief measure however, was to improve the availability of specialised antenatal care chiefly administered by midwives (free care consultations near the homes) for the poor and the less well educated women. The results showed that perinatal deaths in the island dropped to 14.9 per thousand in 1984. The major improvement was that women who had been attended by midwives had 10 per thousand perinatal deaths. This involved half the population of the island and the same results were found as to the wealthier and more educated women who were attended by private obstetricians. It was found to be possible to reduce the difference in the perinatal death rate between an African population in Martinique and an European population in European France.

A randomized comparison of early with conservative use of antihypertensive drugs in the management of pregnancy-induced hypertension.

Two treatment strategies were compared in 155 women with pregnancy-induced hypertension who were also given comprehensive non-pharmacological care. The mean gestation at entry was 28 weeks. As long as the diastolic blood pressure (DBP) remained below 106 mmHg, oxprenolol, or oxprenolol plus dihydralazine, were given to the early treatment group, and matching placebos to the control group. Open antihypertensive treatment was provided for patients whose DBP rose above 105 mmHg. Proteinuria occurred in seven women in each group. In the early treatment group, 13 of the 78 women were delivered by caesarean section; the corresponding numbers in the control group were 27 of 76 (17 vs 36%, 95% confidence interval (CI) of difference: 5-33%); the sections included seven and 16 in the early treatment and control groups, respectively, for severe hypertension and/or fetal distress. There were five perinatal deaths, two in the early treatment group and three in the control group. Early treatment did not influence gestational age at birth or birthweight. Respiratory distress syndrome occurred in four infants in the early treated group and in 10 in the control group; 14 infants in the former group and 26 in the latter were in hospital for more than 10 days (18 vs 35%; 95% CI of difference 4-32%). These results indicate that early antihypertensive treatment with oxprenolol is safe for the fetus and newborn in pregnancy-induced hypertension, but has no advantage over non-pharmacological care in terms of fetal growth. However, it may prevent acute hypertension in late pregnancy and associated fetal distress, and thus reduce the number of caesarean sections.

The prevention of preterm delivery through prenatal care: an intervention study in Martinique.

During 1976-1978, improvements were made in the free prenatal care provided by the maternal and child health authority (PMI) of Martinique. Central to these changes was implementation of a program of preventive prenatal care developed in France by one of the authors (EP). Data on all births during 1980-1982 show no significant difference in pregnancy outcomes between women receiving free prenatal care from the government and women receiving private care from obstetricians.

PIP: This paper reports the results of a prenatal care program in Martinique aimed at preventing preterm deliveries among women of low socioeconomic status. It was based on the assumption that high-quality preventive care during pregnancy can substantially improve pregnancy outcomes among disadvantaged women. During 1976-78, the government's maternal and child health department (PMI) took steps to ensure easy access to prenatal care for all women in Martinique. New service sites were established, existing sites were improved, and health personnel were given special training on the recognition of high-risk pregnancies. The mean number of prenatal visits/woman to government clinics increased from 4.9 in 1978 to 6.2 in 1982. During this period, the percentage of women attending a free clinic in the 1st trimester of pregnancy rose from 39% to 64%. In 1981, 42% of all births were to women who received prenatal care through the PMI and delivered in public facilities. 22% were to women who received prenatal care and delivered within the private health care system, and the remaining 36% were to women to delivered in public facilities but did not received prenatal care through the PMI system. To evaluate the impact of the government prenatal care program, the outcomes of all births in Martinique in 1980, 1981, and 1982 were compared by type of prenatal care. Although women who received private prenatal care belonged to a higher socioeconomic class, there were no significant differences between women receiving private or public prenatal care in terms of preterm deliveries, low birthweight, or perinatal mortality. This finding suggests that the social class effect on pregnancy outcome can be eliminated through preventive prenatal care. It is further noted that the Martinique program did not involve an emphasis on expensive equipment or the services of specialists; rather, patient education and upgrading the skills of midwwives were central features.