Segment angle. The foot segment angle was measured for both high-heeled and normal gait. The minimum angle occurred just after heel strike as the foot has completed the dorsiflexion movement, and the maximum angle occurred right after toe take off as the foot had plantarflexed. Larger angles were measured for the high-heeled gait because of the increased angle caused by the high-heeled shoes. The range of motion for the normal gait movement was 81 degrees, with a maximum of 188 degrees and a minimum of 107 degrees. The high-heeled movement the range of motion was 71 degrees, with a maximum of 197 degrees and a minimum of 128 degrees.
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Figure 3. Foot segment angle during the normal gait (left) or the high-heel gait (right). The segment angle is calculated from a hypothetical plane passing horizontally through the ankle joint in the frontal plane, and parallel to the ground. The anatomical position for the ankle joint is 90 degrees. In both graphs increasing angles indicate clockwise rotation, while decreasing angles indicate counterclockwise rotation. | |
Joint angle 1. The knee joint angle for both movements (normal and high-heeled gait) was analyzed for comparison. The maximum for both movements was about 180 degrees. This was achieved during the stance phase of both movements. During this phase the knee becomes completely extended, flexes a little and then extends once more before toe take off. This explains the slight dip and rise before the swing phase forced flexion at the knee. During extension, or swing phase, the minimum angle for the normal gait movement reaches 116 degrees, while the minimum angle reaches 125 degrees for the high-heeled gait movement. The range of motion for the normal gait movement was 65 degrees, while the range of motion for the high-heeled gait was 55 degrees.
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Figure 4. Knee joint angles in the normal gait (left) and the high-heel gait (right). The angle is calculated from a vertical line passing through the thigh and lower leg segments. The anatomical position for the knee joint is 180 degrees. An angle less than 180 degrees corresponds to flexion and an angle greater than 180 degrees corresponds to hyperextension. | |
Joint angle 2. The ankle motion that is seen between the normal gait and the high heel gait is very similar in timing but is much different in angle size. The maximum angle for the ankle in the normal gait peaks at 125 degrees. This angle is seen approximately 75% into the motion when the ankle is planter flexed while in swing phase preparing for heel strike. The maximum angle in the high-heel gait peaks at 155 degrees. Just as seen in the normal gait, the peak in the ankle joint is seen during the planter flexion approximately 75% into the motion. This also, is during the swing phase, preparing for heel strike. The minimum ankle angle in the normal gait was 100 degrees approximately 48% through the motion. This angle is in direct correlation with the dorsi flexion associated with the stance phase. The minimal angle seen in the high-heel gait is 110 degrees 48% through the motion. Once again dorsi flexion occurs in correlation with the stance phase of the motion. The range of motion in the normal gait is 25 degrees, while the "ROM" in the high-heel gait is 45 degrees.
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Figure 5. Ankle joint angles in the normal gait (left) and the high-heel gait (right). The angle is calculated from the lower leg and foot segments. The anatomical position of the ankle joint is 90 degrees and the angle was measured clockwise from the lower leg segment to the foot segment. Decreasing ankle angles represent dorsiflexion. Increasing angles greater represent plantarflexion. | |
Joint velocity. The angular joint velocity was similar for both the normal gait and the high-heeled gait. Positive values correspond to plantarflexion and negative values correspond to dorsiflexion. There appears to be much more dorsiflexion in the normal gait action than in the high-heeled gait as there are six minima in the normal gait graph and only four in the high-heel gait graph. The initial peak in both graphs represent heel strike for both actions as we started analyzing the motions at this point. For the normal gait, the maximum angular velocity approaches 148 deg/s, and the minimum angular velocity is about 171 deg/s. For the high-heeled gait these numbers change quite a bit as the maximum angular velocity approaches 184 deg/s, and the minimum angular velocity is around 235 deg/s.
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Figure 6. Ankle joint angular velocity in normal gait (left) and in high-heel gait (right). Positive values represent plantarflexion and negative values represent dorsiflexion. | |
Angle-Angle Plot. The coordination of the knee and ankle was different in normal gait and high-heeled gait. The graphs below, of ankle angle versus knee angle, represent the combined action of both ankle dorsiflexion and plantarflexion, and knee flexion and extension. In the normal gait stance phase the knee had flexed while the ankle at first plantarflexed and then dorsiflexed. In the swing phase of normal gait the knee extended and the ankle dorsiflexed and then plantarflexed to complete the cycle. In high-heeled gait during the stance phase the knee was flexed and the ankle again shifted from the initial plantarflexion to dorsiflexion. During the swing phase of the high-heeled gait the knee again extended while the ankle went from dorsiflexion to plantarflexion to once again complete the cycle. Because knee motion was very similar in both normal gait and high-heeled gait the differences in the graphs depict the differences in ankle motion. In both cases the graphs appeared to have a rough sideways figure eight appearance to them because they both represented a single cycle (plantarflexion- dorsiflexion-plantarflexion) of the ankle movement. The high-heeled graph occurs at higher ankle angles because of the increased ankle angle the high-heels cause. The jumbled region in the upper right of each graph represents the heel strike of the movement, at this point the foot absorbs some impact and the ankle angle begins to decrease sharply. The other jumbled region in the bottom right of each graph represents toe take off, and at this point the ankle angle starts to increase rapidly.
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Figure 7. Coordination of the ankle joint angles and the knee joint angles in the normal gait (left) and the high-heel gait (right). The arrow points to the direction of the recorded gait in each movement. Increasing ankle angles correspond to plantarflexion, while decreasing ankle angles correspond to dorsiflexion. Increasing knee angles represent extension and decreasing knee angles represent flexion. | |
