DYNAMIC PLANTAR FOOT PRESSURE MEASUREMENTS (DPFPM) IN ATHLETES
Simsek, D.1, Onarici Gungor, E.1, Yildizer, G.1, Kirkaya, I.2 1:Anadolu University, (Eskisehir, Turkey), 2: Uludag Technic University (Bursa, Turkey)
Introduction
Foot and ankle injuries are extremely common among athletes and other physically active individuals (Chinn, and Hertel 2010). The purpose of this study is to investigate the effect of foot pain on plantar peak pressure, maximum force of right and left foot.
Methods
Nine male athletes who have foot pain (FP) (20.50± 1.16 year; 1.78±0.06m; 76.64±8.93 kg; 23.85±1.74 kg/m2) and 11 athletes (22 ± 3.52 year; 1.78±0.06 m; 75.30±7,74 kg; 23.40±2.41 kg/m2) (as the control group) having no history of surgery related to the lower extremity, and no history of pain in the past 6 months were included in the study. Subjects of FP group was included according to the results of Foot Function Index (FFI) which is composed of items assessing three areas: pain, disability (including impairment), and functional limitation. FFI has been found to have good reliability and validity, and it has had wide appeal to clinicians and research scientists (Budiman-Mak et al. 2013). Dynamic plantar pressure assessment during walking without shoes was undertaken using the EMED-XL (Novel GmbH, Munich, Germany) plantar pressure analysis system. This system consists of platform (platform size:1,529 x 504 mm²; sensor area:1,440 x 440mm²) incorporating 25,344 sensors (4 sensors/cm2) sampling at a rate of 100 Hz. The two-step gait initiation protocol was used to obtain foot pressure data. Five trials have been found to be sufficient to ensure reliability of the pressure data (Bosch and Rosenbaum, 2010). For data analysis the Novel scientific analysis software was used. The following parameters were calculated for the entire foot: Peak pressure (PP in kPa), maximum force (F) contact area (CA in cm2), and contact time (CT in ms). The maximum force was normalized with respect to the body weight of each participant. Foot was masked as ‘big toe, second toe, toes 3-4-5, MH1: 1st metatarsal head, MH2: 2nd metatarsal head, MH3: 3rd metatarsal head, MH4: 4th metatarsal head, MH5: 5th metatarsal head, middle foot and hind foot’. Before statistical analyses, all of the measures were found to be distributed normally based on the Shapiro-Wilk test. It was examined whether there were any statistically significant differences between the experiment and control group means using independent T test. In the measurements 95% reliability range and P < 0.01 – 0.05 were accepted as significance level.
Discussion
According to descriptive data there is no significant differences of age, height, weight, BMI between the FP and FFP groups (P>0.05). It was found that there were significant differences between the FP and FFP group in terms of relative maximum force (%BW) in total foot (FP: 95.57±4.84; FFP: 90.37±4.73), big toe (FP: 15.57±3.40; FFP: 9.07±4.30) and second toe (FP: 3.07±1.17; FFP: 1.92±1.10) (P<0.05). In addition to this data absolute maximum force of hind foot (FP:450.94±68.15; FFP: 366.51±109.59), big toe (FP:120.16±33.17; FFP:69.21±36.10) and second toe (FP:23.68±9.22; FFP:14.60±8.73) were found statistically different between FP and FFP groups (P<0.05). Relative peak pressure of big toe (FP: 33.36±7.26; FFP:26.87±7.36) was found statistically different between groups (P<0.05). Contact area (cm2) of total foot (FP: 165.22±17.70; FFP:150.53±11.66) and MH1 (FP: 15.37±1.46; FFP:13.53±1.36) was found statistically different between groups (P<0.05). In our findings, it was found that the peak pressure, maximum force and contact area in FP group was higher than FFP group. Increased foot pain would be associated with higher peak plantar pressure, maximum force and contact area. Underlying mechanism of these findings may be related with angle deviation of subtalar varus and valgus.
References
Budiman-Mak, E, Conrad, KJ, Mazza, J. and Stuck, RM. ( 2013). A review of the foot function index and the foot function index. Journal of Foot and Ankle Research, 6(5).
Bosch, K, Rosenbaum, D. (2010). Gait symmetry improves in childhood—A 4-year follow-up of foot loading data. Gait & Posture 32, 464–468.