EVALUATION OF PRESSURE DISTRIBUTION OF KYBOOT SHOES IN COMPARISON TO OTHER FOOT WEAR IN DIABETIC PATIENTS AND IN HEALTHY SUBJECTS

Siev-ner I 1, Dotan Marom Y 1, Portnoy S 2, Levy S 1

1
Sheba Medical Center, Department of Orthopedic Rehabilitation, Tel Hashomer, Ramat Gan, Israel
2 Department of Medical Professions, University of Tel Aviv, Tel Aviv, Israel

BACKGROUND
Every 30 seconds a limb is lost somewhere in the world as a consequence of diabetes. These amputations are preceded by a foot ulcer in 84% of cases. Therefore, to reduce risk of ulceration, relief of mechanical pressure is indicated. Currently therapeutic footwear, custom made, is provided by the Ministry of Health to diabetic patients that are at risk of developing foot ulcers. The Kybun shoe could offer a cheaper yet effective solution to prevent foot ulcers and concomitantly achieve better compliance as it looks like ordinary shoes.

AIM
Comparison and evaluation of pressure distribution, gait pattern, changes in the movement of the center of pressure, and comfort of wear using KyBoot shoes versus normal foot wear in diabetic and healthy subjects.

METHOD 
10 healthy subjects and 11 individuals with diabetes participated in our study. Neuropathy was defined as the inability to sense the pressure of a 10g monofilament in 5 out of 9 pre-determined points on the plantar side of the patients' feet.

We measured the pressure distribution and movement of the Center of Pressure with insole pressure sensors (Tactilus®) which is able to record pressure up to 30 psi (206 kpa) in real-time. Gaitrite® is a gait analysis walkway system that  provided data on gait characteristics. The participants were asked to complete a questionnaire on comfort of wear and satisfaction on both the normal and Kyboot shoes.

RESULTS
We did not find significant difference between the diabetic and non-diabetic participants. The maximal heel to forefoot pressure ratio was significantly lower in gait with KyBoot shoes 9.7±5.6 compared to 23.7±14.0 in normal shoes (p<.001), (See Fig. 1)

Figure 1.


During gait, the average pressure was significantly lower with the Kybun shoes compared to the regular shoes (42.9±10.7kPa and 49.1±11.4kPa, respectively; p<.001). The kybun shoes increased the maximal contact area from 121.8±13.9cm2 to 126.8±14.5cm2 (p=.011).The subjects ambulated with reduced medio-lateral (2.0±0.4mm and 2.5±0.5mm,; p<.001) and anterior-posterior (12.3±2.4mm and 14.6±2.0mm,; p<.001 movement of the Center of Pressure, for Kybun and normal shoes respectively.

DISCUSSION & CONCLUSION
In both groups, the measured objective parameters as well as the subjective questionnaire information support the potential of reduction of the risk for foot ulcers and thus the risk for amputations in diabetic patients. The study limitations: we examined the Kyboot against the regular shoe which the patient is using daily. The sample size is relatively small.