Wearing high-heeled shoes on a side slope makes standing balance unstable.

INTRODUCTION: Many women wearing high-heeled footwear are at high risk of falls. Past studies have examined the balance on level ground or balance during walking. We measured the standing balance on the ground and side slopes for 18 healthy women. METHOD: Body sway was evaluated based on the center of pressure (COP) while participants stood on level ground on a side slope. The total locus length as well as rectangular and outer peripheral areas were then measured using a Zebris system. Measurements were compared under bare feet, normal shoe, and high-heeled shoe conditions. RESULTS: On level ground, there were no significant differences among the three conditions. On the side slope, the total locus length (TLL), rectangular area (RA) and outer peripheral areas (OPA) were significantly greater for the high-heeled shoes than for the bare feet and normal shoes. Standing on the side slope caused larger body sway than on the level ground, along with a higher risk of falling. DISCUSSION: In TLL, OPA, and RA, the COP moved outside substantially when participants stood on a slope in high heels than in shoes. High heels were highly unstable for standing on a slope since the ankle joint of one leg is in plantar flexion, the foot is pronated, and the other side is plantarflexed at the ankle with pronation of the foot. CONCLUSION: High-heeled shoes significantly alter a person's balance when standing on a side slope, suggesting a high risk of falling.

Recovery process of the muscle activities during walking with efficient early quadriceps training and gait exercises after total knee arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) by the trivector approach is less invasive to the knee extensor mechanism; early quadriceps training is possible and a good prognosis is expected after surgery. However, investigations regarding lower limb muscle activity during gait have not been reported after using the trivector approach. To determine an effective postoperative rehabilitation program, we analyzed the recovery processes of leg muscle activities during walking. METHODS: Fourteen subjects with severe knee osteoarthritis (OA) who underwent early exercises after TKA by trivector approach were included in the TKA group. The control group consisted of eight patients with mild knee OA. Surface electromyography of the vastus medialis (VM), vastus lateralis (VL), and rectus femoris (RF) muscles were recorded and gait speed and step length were measured. The TKA group was measured postoperatively at 3, 12, and 24 weeks. RESULTS: Gait speed of TKA group significantly increased at 12 weeks post-surgery and recovered equal to the control group at 24 weeks. Additionally, step length reached the level of control subjects at 24 weeks. Postoperative activity of VM returned to that of the control group at 12 weeks. VL continued decreasing until 12 weeks compared with the preoperative values, but gradually increased and became equal to the control group at 24 weeks. RF slightly increased at 3 weeks postoperation and remained stable. CONCLUSIONS: VM injury by the trivector approach might be small and temporary.Functional recovery of VL was important and early starting rehabilitation program up to 24 weeks is appropriate.

Does distal tibiofibular joint mobilization decrease limitation of ankle dorsiflexion?

Limitation of ankle motion is in many cases treated by joint mobilization (JM), a kind of manual physical therapy technique. Until now, the JM approach has mainly focused on the talocrural joint, with less attention to the distal tibiofibular joint. We applied cyclic loading to the lateral malleolus as in JM in order to clarify the relationship between the dorsiflexion angle and the excursion of the lateral malleolus. Seven normal, fresh-frozen cadaver legs were used. To each specimen, cyclic loading with a 30N force was applied 1000 times to the lateral malleolus at a speed of 15N/s. The displacement of the lateral malleolus was measured with a magnetic tracking system. The maximum dorsiflexion angle was measured before and after cyclic loading. After the first 100 and 1000 times of cyclic loading, the tibia was displaced 0.44+/-0.30mm and 0.75+/-0.36mm, respectively, and the fibula was displaced 0.44+/-0.28mm and 0.92+/-0.39mm, respectively. The average dorsiflexion angle increased from 14.36+/-7.51 degrees to 16.74+/-7.21 degrees after cyclic loading (P<0.05). Movement of the distal tibiofibular joint led to a significant increase in the range of ankle dorsiflexion. These results suggest that tibiofibular JM would be effective for limitation of ankle dorsiflexion.