Vibration perception among children and adolescents with Charcot-Marie-tooth disease and implications for foot posture.

BACKGROUND: Alterations in vibration perception among children and adolescents with Charcot-Marie-Tooth disease might explain observed changes in foot posture. Therefore, this cross-sectional study compared the vibration perception of the lower limbs in youths with and without Charcot-Marie-Tooth disease and verified the cut-off value of the distal vibration perception for the Charcot-Marie-Tooth group. In addition, associations between dynamic plantar pressure, vibration perception and isometric muscle strength were investigated. METHODS: Participants aged 9-18 (Charcot-Marie-Tooth group n = 32; Typical group n = 32) had vibration perception measured by a 128-Hz graduated tuning fork. The static and dynamic foot posture were evaluated by the Foot Posture Index and pressure distribution measuring system, respectively. For the Charcot-Marie-Tooth group, a hand-held dynamometer evaluated the isometric muscle strength of the lower limbs. FINDINGS: Children with Charcot-Marie-Tooth disease presented impaired vibration perception at the distal phalanx of the hallux and head of the first metatarsal compared to their typically developing peers, while adolescents with Charcot-Marie-Tooth disease showed impairment in all the tested regions compared to their typically developing peers. The cut-off value for vibration perception for participants with Charcot-Marie-Tooth disease was 5.7, considering the original grade of the tuning-fork 128 Hz. Among the associations established for the Charcot-Marie-Tooth group, a greater vibration perception at the distal phalanx of the hallux was associated with a longer rearfoot contact time (ß = 31.02, p = 0.04). INTERPRETATION: These new findings may guide the clinical evaluation and rehabilitation treatment for children and adolescents with Charcot-Marie-Tooth disease.

Changes in the plantar pressure distribution during gait throughout gestation.

BACKGROUND: The intention of this investigation was to longitudinally describe and compare the plantar pressure distribution in orthostatic posture and gait throughout pregnancy. METHODS: A prospective longitudinal observational study was conducted with six pregnant women (mean ± SD age, 32 ± 3 years) with a mean ± SD weight gain of 10.0 ± 1.4 kg. Peak pressure, contact time, contact area, and maximum force in five plantar areas were evaluated using capacitive insoles during gait and orthostatic posture. For 1 year, the plantar pressures of pregnant women were evaluated the last month of each trimester. Comparisons among plantar areas and trimesters were made by analysis of variance. RESULTS: For orthostatic posture, no differences in contact time, contact area, peak pressure, and maximum force throughout the trimesters were found. During gait, peak pressure and maximum force of the medial rearfoot were reduced from the first to third and second to third trimesters. Maximum force increased at the medial forefoot from the first to second trimester. Contact area increased at the lateral rearfoot from the second to third trimester and at the midfoot from the first to third trimester. Contact time increased at the midfoot and medial and lateral forefoot from the first to third trimester. CONCLUSIONS: Pregnant women do not alter plantar pressure during orthostatic posture, but, during gait, the plantar loads were redistributed from the rearfoot (decrease) to the midfoot and forefoot (increase) throughout pregnancy. These adjustments help maintain the dynamic stability of the pregnant woman during locomotion.