Abstract
Increase in heel height increases peak pressure under the forefoot. Customized shoe inlays with metatarsal lift, arch support has demonstrated lowered forefoot pressure and increase in the subjective comfort. A commercial shoe brand (Roccamore) has introduced an off-the-rack stiletto with a slim (1 cm2) 8 cm heel plus 2 cm platform with metatarsal lift, arch support and heel cap claiming it will reduce the discomfort associated with high heels. The primary aim of this study was to compare the pressure under the forefoot, arch, heel and toes in this “orthopaedic” stiletto (OS) to a standard stiletto of the same heel height without inlays (SS) and a control sneaker (SN). Secondary aims were to measure the comfort under the forefoot, heel and arch during everyday use. Finally to investigate if any pressure measurements were correlated to comfort or any anatomical/clinical feature of the foot.
22 women, aged 40 (21–62), accustomed to stilettos, walked at 4 km/hr on a level treadmill in all three shoe types. Peak pressure (kPa) and pressure-time integral (kPa/sec) under 2+3rd and first metatarsal heads, the arch/midfoot and heel were measured during 10 consecutive steps at 50 Hz using Novel Pedar-X pressure distribution insoles. Standing X-rays and a standardized clinical examination were carried out. Mundermanns comfort VAS and daily steps were recorded for each shoe type during 3 full days. (0= worst to 150 mm= most comfortable). Data were compared with paired t-tests and regression analysis. Statistical significance is reported as p<0.05=, p<0.01=, p<0.001=.
Peak pressure: Compared to SS the peak pressure under the 2+3 metatarsals was reduced to 82% in the OS and 60% in the SN. Under the first metatarsal it was reduced to 73% and 40%, respectively. Under the arch it was similar for SN and OS and 30% lower for the SS. Under the heel the OS was 27–28% lower than SS and SN.
The same reductions, as well as similarities in the arch were seen in the pressure-time integrals, although with smaller difference between OS and SS, and conversely larger reductions in the SN to 49% under 2+3 metatarsals and 43% under the first.
For forefoot, arch and heel, the comfort was rated highest for the SN and lowest for the SS. No statistical difference between OS and SS in the arch.
For each mm the second metatarsal was longer than the first, the peak pressure under MT2+3 rose 13 kPa (95%CI: 7 to 19) and the pressure time integral 3 kPa/s (1–5). No effect of first ray ROM or stability. The forefoot VAS score dropped (less comfortable) 0.3 mm for each kPa/s the pressure time integral rose under the MT2+3. Peak pressure parameters or daily steps were not statistically significantly related to the forefoot comfort.
A mass produced “orthopaedic” stiletto can reduce the pressure approaching those achieved in a sneaker and increase comfort for the user. An increase in pressure-time integral under 2+3 metatarsals increases the discomfort and the pressure is increased in index-minus feet.
