Segment angle. The angle of the trunk segment was analyzed for both normal and high-heel gait. The maximum angle occurred just after heel strike, and the minimum angle occurred during the transition from stance phase to swing phase for each movement. The range of motion for normal gait was 16 degrees, with a maximum angle of 10 degrees and a minimum angle of -6 degrees. The range of motion for high-heel gait was 14 degrees, with a maximum angle of 11 degrees and a minimum angle of -3 degrees.
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Figure 3. Trunk angle during normal gait (left) and high-heel gait (right). Trunk angle was calculated between the trunk segment and a vertical axis through the hip joint, where upright position (anatomical) corresponds to zero degrees. Positive values represent clockwise rotation of the trunk and negative values represent counterclockwise rotation of the trunk. | |
Segment velocity. The angular velocity of the trunk segment was similar for both normal gait and high-heel gait. The maximum angular velocity of the trunk segment was 61 deg/s for both normal gait and high-heel gait, occurring during the swing phase for both movements. The minimum angular velocity was -61 deg/s for normal gait and -45 deg/s for high-heel gait.
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Figure 4. Trunk angular velocity in normal gait (left) and high-heel gait (right). Positive velocity represents clockwise rotation of the trunk. | |
Joint angle1. The cycle of ankle motion was different for normal gait and high-heel gait. Normal gait had two distinct maximums, 121 degrees and 124 degrees occurring at 11.6% and 67.8% of total movement time. The two minimums, both measuring 96 degrees, occurred at 41% and 85.7% of total movement time respectively. The average ankle angle in normal gait was 108 degrees. The total range of motion for normal gait was 25 degrees. High-heel gait had only one maximum, 156 degrees, occurring at 15.6% of total movement time. The minimum occurred at 123 degrees and at 67% of total movement time. The average ankle angle in high-heel gait was 140 degrees. This increase in average ankle angle was due to the plantarflexion caused by the height of the heel. The total range of motion for high-heel gait was 33 degrees. The cycle of motion in normal gait is doubled of that in high-heel gait.
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Figure 5. Ankle joint angles in normal gait (left) and high-heel gait (right). The anatomical position of the ankle joint is 110 degrees for normal gait and approximately 140 degrees for high-heel gait. The ankle joint for normal gait was calculated clockwise from the shank segment. An ankle angle less than 110 degrees for normal gait, and 140 degrees for high-heel gait represents dorsiflexion and an ankle angle greater represents plantarflexion. The ankle joint for high-heel gait was calculated clockwise from the shank segment. | |
Joint angle 2. The hip joint motion for normal gait and high-heel gait was similar. The maximum hip angle occurred at maximum extension, and corresponded to the toe off portion of the gait cycle. The maximum hip joint angle for normal gait was 192 degrees and occurred after 59% of the total movement time had elapsed, and the maximum angle for high-heel gait was 191 degrees after 58% of the total movement time had elapsed. The minimum hip angle occurred at maximum flexion, which corresponded to heel strike. The minimum angle for normal gait occurred at 153 degrees and after 2% of the total movement time had elapsed, and high-heel gait at 152 degrees and after 1% of the total movement time had elapsed. The range of motion of the hip angle was the same for both movements (39 degrees).
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Figure 6. Hip joint angles in normal gait (left) and high-heel gait (right). The anatomical position of the hip joint is 180 degrees. The hip joint angle was calculated between the trunk and thigh segments, where a hip angle less than 180 degrees corresponds to hip flexion and a hip angle greater than 180 degrees corresponds to hip extension. | |
Angle-Angle Plot. The coordination of the hip and ankle was different in normal and high-heel gait. The graph of the hip joint angle versus the ankle joint angle represents the combined action of hip flexion and extension, and ankle plantarflexion and dorsiflexion. For the stance phase of normal gait in which the hip was extending, the initial movement of the ankle was plantarflexion, followed by dorsiflexion, and finally plantarflexion. During the swing phase, the hip was flexed while the ankle dorsiflexed, followed by a plantarflexion to prepare for the next heelstrike. For the stance phase of high-heel gait in which the hip was extended, the ankle plantarflexed and then dorsiflexed. During the swing phase, the hip was flexed and the ankle proceeded to plantarflex to prepare for the next heelstrike. Because hip motion was similar in the two gaits, differences in the graphs reflect differences in ankle motion. The graph of high-heel gait appeared like a "figure 8" because of the single cycle of ankle movement (plantarflexion-dorsiflexion-plantarflexion), whereas the graph of normal gait appeared "zig-zaged" because it represents two cycles of this ankle movement.
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Figure 7. Coordination of the ankle joint and the hip joint angles in normal gait (left) and high-heel gait (right). The arrow points in the direction of the recorded gait. | |
