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- Author or Editor: Mark W. Cornwall x
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One hundred fifty-three subjects between the ages of 18 and 41 years (mean age, 26.2 years) with no history of congenital or traumatic deformity or foot problems walked along a 6-m walkway while the angular and linear displacement of the tibia, calcaneus, navicular, and first metatarsal was measured by means of an electromagnetic motion analysis system. Three-dimensional movement of the calcaneus relative to the tibia, of the navicular relative to the calcaneus, and of the first metatarsal relative to the navicular during the stance phase of gait was calculated. The results of this study provide information on, and an understanding of, how the calcaneus, navicular, and first metatarsal function during the stance phase of normal human walking. (J Am Podiatr Med Assoc 92(2): 67-76, 2002)
The purpose of this study was to determine the reliability and validity of two center-of-pressure quantification methods. One hundred five individuals (33 men and 72 women) with a mean age of 26.7 years participated in phase 1 of the study. Two measures of the center-of-pressure pattern, the lateral-medial area index and the lateral-medial force index, were calculated from plantar pressure data collected on all subjects. Between-trial reliability of the two measurements was assessed using intraclass correlation coefficients. In phase 2, frontal plane motion of the rearfoot was recorded in 30 individuals. Pearson correlation coefficients were then calculated between the two center-of-pressure indices and the magnitude of rearfoot eversion obtained from each subject during walking. Intraclass correlation coefficient values ranged from 0.374 to 0.889 for the lateral-medial area index and from 0.215 to 0.905 for the lateral-medial force index. Pearson correlation coefficients between the two center-of-pressure indices and the rearfoot kinematic variables ranged from 0.050 to 0.165. The lateral-medial area index and the lateral-medial force index may have adequate between-trial reliability but are not related to the magnitude of frontal plane rearfoot eversion during the stance phase of walking. (J Am Podiatr Med Assoc 93(2): 142-149, 2003)
Background: A study was conducted to determine whether the longitudinal arch angle can be used to predict dynamic foot posture during running.
Methods: Seventeen healthy, experienced runners participated in the study. The static longitudinal arch angle was determined from a digital image of the medial aspect of each subject’s feet obtained in relaxed standing posture. For the dynamic phase, subjects were asked to walk across a 12-m walkway and then to run across a 25-m runway while the medial aspect of each foot was videotaped. The longitudinal arch angle was digitized from the video images at midstance in walking and at midsupport while running for five trials per extremity.
Results: The longitudinal arch angle obtained in relaxed standing posture was highly predictive of dynamic foot posture at midstance in walking (r 2 = 0.854) and at midsupport while running (r 2 = 0.846).
Conclusions: The static measurement of longitudinal arch angle is highly predictive of dynamic foot posture during walking and running. The longitudinal arch angle measured in relaxed standing posture significantly contributed to explaining more than 85% of the variance associated with the longitudinal arch angle position at midstance during walking and at midsupport while running. These results seem to validate use of the longitudinal arch angle as part of the foot and ankle physical examination. (J Am Podiatr Med Assoc 97(2): 102–107, 2007)
To determine whether differences exist in the longitudinal arch angle based on sex or extremity, the longitudinal arch angle was assessed in 21 men and 21 women using a digital image of the medial aspect of each subject’s feet. The image was obtained with the subject in relaxed standing posture and in maximum internal rotation of the lower leg. To determine whether the longitudinal arch angle could be used to predict dynamic foot posture during walking, 50 different subjects were asked to walk across a 6-m walkway while the medial aspect of each foot was videotaped. The longitudinal arch angle was digitized from digital images obtained at midstance for three walking trials. No differences in the longitudinal arch angle were found based on sex or extremity. The longitudinal arch angles obtained in the static positions of relaxed standing posture and maximum internal rotation were highly predictive of dynamic foot posture at midstance during walking. Relaxed standing posture and maximum internal rotation significantly contributed to explaining more than 90% of the variance associated with the longitudinal arch angle position at midstance during walking. These results validate use of the longitudinal arch angle as part of the foot and ankle physical examination. (J Am Podiatr Med Assoc 95(2): 114–120, 2005)
A study was conducted to determine whether plantar surface contact area measures calculated from footprints collected during walking can be used to predict the height of the medial longitudinal arch. Thirty healthy women participated in the study. Arch height was determined by the distance from the navicular tuberosity to the floor and by the “bony” arch index. Dynamic plantar surface contact area was recorded using a pressure platform as the subjects walked across a 12-m walkway. The arch index and the total plantar surface contact area were determined from the pressure sensor data. The results indicated that plantar surface contact area could be used to estimate only approximately 27% of the height of the medial longitudinal arch as determined by navicular tuberosity height and the bony arch index. These findings demonstrate the inability of the clinician to predict the vertical height of the medial longitudinal arch on the basis of the amount of foot plantar surface area in contact with the ground during walking. (J Am Podiatr Med Assoc 96(6): 489-494, 2006)
Background: Classification of rearfoot motion patterns would assist in understanding normal rearfoot motion and would facilitate the identification of abnormal motion. We sought to identify common frontal plane rearfoot motion patterns in an asymptomatic population.
Methods: Frontal plane rearfoot motion was measured with an electromagnetic motion analysis system in 279 asymptomatic individuals during barefoot walking. The coefficient of multiple correlation and visual observation were used to identify similar patterns of rearfoot motion.
Results: Four distinct rearfoot motion patterns were identified: pattern 1 consisted of 176 individuals (63.1%) and was labeled “typical” eversion, pattern 2 consisted of 87 individuals (31.2%) and was labeled “prolonged eversion,” pattern 3 consisted of nine individuals (3.2%) and was labeled “delayed eversion,” and pattern 4 consisted of seven individuals (2.5%) and was labeled “early eversion.”
Conclusions: Asymptomatic frontal plane rearfoot motion can be classified into four distinct patterns, but most individuals (94.3%) exhibit one of two motion patterns (typical or prolonged eversion). (J Am Podiatr Med Assoc 99(5): 399–405, 2009)
Background: Foot orthoses have been described as a possible intervention for individuals with patellofemoral joint pain. No study has attempted to quantify the perceived comfort and support of foot orthoses when used as an intervention for patellofemoral joint pain.
Methods: A randomized case-control trial with crossover between contoured and flat orthoses was conducted on ten individuals with patellofemoral pain and ten healthy participants. All of the participants completed a comfort-support assessment and had in-shoe plantar pressure data collected before and after 3 weeks of wear. A 1-week washout period was used to minimize any continued treatment effect between orthotics testing. The patellofemoral pain group also completed a numeric rating scale to assess pain reduction after using each orthosis.
Results: All of the participants perceived that greater support was provided by the contoured orthoses in the heel and arch regions. Even with a 30% difference in material hardness between the two orthoses, all of the participants rated cushioning as equivalent. Six individuals in the patellofemoral pain group reported a clinically significant reduction in knee pain as a result of wearing foot orthoses.
Conclusions: A key factor in the selection of contoured foot orthoses versus flat inserts is the amount of support that an individual perceives in the arch and heel regions. In addition, clinicians using foot orthoses as an intervention for patellofemoral pain should expect an individualistic, nonsystematic response. (J Am Podiatr Med Assoc 101(1): 7–16, 2011)
The purpose of this study was to determine the degree of symmetry for in-shoe plantar pressure and vertical force patterns between the left and right feet of healthy subjects during walking. Thirty subjects with a mean age of 29.6 years participated in the study. Each subject walked a distance of 8 m three times while in-shoe plantar pressure and vertical force data were collected. A total of 12 steps were analyzed for both feet, and maximum vertical force, peak pressure, and pressure-time integrals were calculated for four plantar regions of the foot. No differences in the three variables were noted between male and female subjects. Plantar pressure and vertical force patterns were found to be symmetrical between the left and right feet, except for two of the four plantar regions studied. Only the forefoot and rearfoot regions were found to show significant differences between the left and right feet for plantar pressure and vertical force, respectively. The degree of asymmetry for these two plantar regions in the same foot, however, was minimal. (J Am Podiatr Med Assoc 91(7): 337-342, 2001)
Background: Recent research has discussed the use of low-frequency electrical stimulation to increase blood flow by eliciting muscular contraction in soft tissues. This randomized clinical trial examined the efficacy of low-frequency electrical stimulation combined with stretching exercises and foot orthoses in individuals diagnosed as having plantar fasciitis for less than 6 months.
Methods: Twenty-six participants aged 18 to 65 years diagnosed as having plantar fasciitis were randomly assigned to two treatment groups: a control group receiving only stretching and orthoses and a treatment group receiving low-frequency electrical stimulation in addition to stretching and orthoses. To assess treatment response, a visual analog scale was used to determine first-step morning pain, and changes in daily activity levels were monitored by using a validated outcome measure. All of the participants were assessed before starting treatment, after 4 weeks of treatment, and 3 months after the conclusion of treatment.
Results: Participants in the control and experimental groups demonstrated pain reduction and improvements in functional activity levels after 4 weeks and 3 months.
Conclusions: Regardless of whether low-frequency electrical stimulation was used as an intervention, the use of plantar fascia–specific stretching and prefabricated foot orthoses provided short-term (3-month) pain relief and improvement in functional activity levels. (J Am Podiatr Med Assoc 99(6): 481–488, 2009)
Background:
We sought to determine whether foot posture and foot mobility were increased in individuals with patellofemoral pain syndrome compared with individuals in a control group.
Methods:
A nested case-control design was used with two controls matched to each patient by sex and age (±1 year). Participants included 43 individuals with a history of unilateral or bilateral patellofemoral pain syndrome and 86 participants in a control group. Data collected included height, weight, and five different measures of foot height and width in weightbearing and nonweightbearing that have been previously shown to have high levels of reliability.
Results:
Individuals with patellofemoral pain syndrome were found to be four times more likely (odds ratio, 4.04; 95% confidence interval, 1.45–11.32) to have a larger-than-normal difference between nonweightbearing and weightbearing arch height compared with those in the control group. The mean values for difference in arch height and foot mobility magnitude were also statistically significant between the patient and control groups. Foot posture, as determined using the arch height ratio, was not significant between groups (odds ratio, 0.94; 95% confidence interval, 0.34–2.61).
Conclusions:
Although foot posture may not be different between individuals with patellofemoral pain syndrome and controls, foot mobility assessed using difference in arch height and foot mobility magnitude is different between the two groups. (J Am Podiatr Med Assoc 101(4): 289–296, 2011)
