Background: Pronated foot posture (PFP) contributes to excessive dynamic knee valgus (DKV). Although foot orthoses such as medial arch support (MAS) are widely and easily used in clinical practice and sports, few studies have investigated the effect of MAS on the improvement of DKV during stair descent in individuals with a PFP. Moreover, no studies reported the degree of improvement in DKV according to the severity of PFP when MAS was applied. Objects: This study aimed to examine the immediate effect of MAS on DKV during stair descent and determine the correlation between navicular drop distance and changes in DKV when MAS is applied. Methods: Twenty individuals with a PFP (15 males and five females) participated in this study. The navicular drop test was used to measure PFP severity. The frontal plane projection angle (FPPA) was calculated under two conditions, with and without MAS application, using 2-dimensional video analysis. Results: During stair descent, the FPPA with MAS (173.1° ± 4.7°) was significantly greater than that without MAS (164.8° ± 5.8°) (p < 0.05). There was also a significant correlation between the navicular drop distance and improvement in the FPPA when MAS was applied (r = 0.453, p = 0.045). Conclusion: MAS application can affect the decrease in DKV during stair descent. In addition, MAS application should be considered to improve the knee alignment for individuals with greater navicular drop distance.

Background: Considering the kinetic chain of the lower extremity, a pronated foot position (PFP) can affect malalignment of the lower extremity, such as a dynamic knee valgus (DKV). Although the DKV during several single-leg movement tests has been investigated, no studies have compared the differences in DKV during a single-leg step down (SLSD) between subjects with and without PFP. Objects: The purpose of this study was to compare the DKV during SLSD between subjects with and without PFP. Methods: Twelve subjects with PFP (9 men, 3 women) and 15 subjects without PFP (12 men, 3 women) participated in this study. To calculate the DKV, frontal plane projection angle (FPPA), knee-in distance (KID), and hip-out distance (HOD) during SLSD were analyzed by twodimensional video analysis software (Kinovea). Results: The FPPA was significantly lower in PFP group, compared with control group (166.4° ± 7.5° and 174.5° ± 5.5°, p < 0.05). Also, the KID was significantly greater in PFP group, compared with control group (12.7 ± 3.9 cm and 7.3 ± 2.4 cm, p < 0.05). However, the HOD not significantly differed between two groups (12.7 ± 1.7 cm and 11.4 ± 2.5 cm, p > 0.05). Conclusion: The PFP is associated with lower FPPA and greater KID. When assess the DKV during SLSD, the PFP should be considered as a crucial factor for occurrence of DKV.

Background: Hallux valgus (HV) is a foot deformity developed by mediolateral deviation of the first metatarsophalangeal joint. Although various foot-toe orthoses were used to correct the HV angle, verification of the effects of kinetics variables such as ground reaction force (GRF) through three-dimensional (3D) gait analysis according to the various type of orthoses for HV is insufficient. Objects: This study aimed to investigate the effect of soft and hard types of foot and toe orthoses to correct HV deformity on the GRF in individuals with HV using 3D motion analysis system during walking. Methods: Twenty-six subjects participated in the experiment. Participants had HV angle of more than 15° in both feet. Two force platforms were used to obtain 3D GRF data for both feet and a 3D motion capture system with six infrared cameras was used to measure exact stance phase point such as heel strike or toe off period. Total walk trials of each participant were 8 to 10, the walkway length was 6 m. Two-way repeated measures ANOVA was used to determine the effects of each orthosis condition on the various GRF values. Results: The late anteroposterior maximal force and a first vertical peak force of the GRF showed that the hard type orthosis condition significantly increased GRF compared to the other orthosis conditions (p < 0.05). Conclusion: There were significant effects in GRF values when wearing the hard type foot orthosis. However, the hard type foot orthosis was uncomfortable to wear during walking. Therefore, it is necessary to develop a new foot-toe orthosis that can compensate for these disadvantages.

The purpose of this study was to evaluate the effect of joint mobilization and manual stretching exercises in patients with hallux valgus. Twenty-three participants were divided into two groups; joint mobilization (n=11) and manual stretching exercises (n=12). The subjects participated in the experiment for 15minutes, three times a week, four weeks. The joint mobilization (Grade III, Maitland) was performed to experimental group for a minute and then rested for 10 seconds for each set. The manual stretching was performed to control group with three exercise session (preparatory and finishing exercises, agonist contraction exercises, agonist contraction and hold-relax exercises). In the results of the study, intragroup comparison of the deformity angles (DA) was shown to decrease from 15.18° to 13.09° in the joint mobilization group (p<.05) and from 19.00° to 16.83° in the stretching exercises group (p<.05). However, left static foot pressure (LSFP), right static foot pressure (RSFP), left dynamic foot pressure (LDFP) and right dynamic foot pressure (RDFP) did not significantly increase or decrease after the experiment. Intergroup differences also were not statistically significant in all variables (p>.05). The current study suggests that JM and MSE are effective in decreasing the DA in patients with hallux valgus.

The aim of this study was to observe the effects of kinesiotaping and joint mobilization on the metatarsophalangeal joint angle and pain in hallux valgus patients Twenty-one female hallux valgus patients in their 20s were divided into two groups, a Kinesiotaping group (KT, n=10) and another group with the addition of joint mobilization (KTJM, n=11). After undergoing 6 weeks of intervention, the change in the metatarsophalangeal joint and pain were measured. Metatarsophalangeal joint angle was significantly increased both the KT and the KTMJ group after intervention. In the change of pain, both the KT and KTJM groups on an individual basis also experienced a significant decrease in pain, though comparison between the two groups failed to represent a significant difference. These findings suggest that Kinesiotatping and joint mobilization increased the joint angle and reduced pain.

Background: The toe-spread-out (TSO) exercise has been introduced as a strengthening exercise for the abductor hallucis muscle in subjects with hallux valgus. Visual biofeedback using ultrasound imaging during exercise, may increase the ability to selectively contract the abductor hallucis muscle, compared with exercise alone. Objects: The aim of this study was to investigate the effects of ultrasound imaging visual feedback during the TSO exercise with respect to its influence on the angle of the first metatarsophalangeal joint (1st MPJ) and the cross-sectional area (CSA) of the abductor hallucis muscle in subjects with hallux valgus. Methods: Twenty-five healthy young subjects with a mean average age of 22.5 years, and a standard deviation of 2.3 years, were recruited for this study. Hallux valgus was defined as an angles greater than 15° angle of 1st MPJ. Goniometric measurement was used to determine the angle of 1st MPJ. In addition, an ultrasound system was used to collect the CSA of the abductor hallucis muscle in each foot. The angle of the 1st MPJ and CSA of the abductor hallucis were measured in three positions; the resting position, during TSO exercise, and during TSO exercise in conjunction with real-time ultrasound imaging feedback. All data analyzed using a repeated analysis of variance with Bonferroni correction in order to compare the dependent variables in all three positions. Statistical level of significance was set up as p<.05. Results: The angle of the 1st MPJ was noted to be significantly reduced and the CSA of the abductor hallucis to be significantly greater during TSO exercise used in conjunction with ultrasound imaging visual feedback, compared to when the values were recorded during TSO exercise alone (p<.05). Conclusion: Based on these findings, it can be concluded that the application of ultrasound imaging visual feedback during TSO exercise is more effective in contracting selectively the abductor hallucis than the use of exercise alone.

The purpose of this study was to investigate the reliability and validity of goniometer measurements of the hallux valgus angle (HVA) compared to radiographic measurements, which are the current standard. Twenty subjects (10 female, 10 male) were recruited for this study (40 feet). The HVA of the subjects was measured using goniometer and radiographic measurement. In three trials, measurements were taken of each subject by two examiners using goniometer and radiographic measurements using radiography in a standing position. The reliability of the measurements was investigated using intraclass correlation coefficients (ICC(3,1)), and the validity was tested using the Pearson product-moment correlation coefficient and an independent t-test. The intra-rater reliability of left and right HVAs were poor (ICC=.409 and .341, respectively). The inter-rater reliability of left and right HVAs were poor and moderate (ICC=.303 and .501, respectively). Left and right HVAs measured using goniometer and radiographic measurements were also poor and moderate (Pearson r=.246 and .544, respectively). These results suggest that goniometer measurements of the HVA are inaccurate and have unacceptable validity compared to radiographic measurements.

The purpose of this study was to determine whether gender differences existed in knee valgus kinematics in college students when performing a vertical drop landing. The hypothesis of this study was that females would demonstrate greater knee valgus motion. These differences in knee valgus motion may be indicative of decreased dynamic knee joint control in females. This study compared the initial knee valgus angle and maximum knee valgus angle at the instant of impact on vertical drop landings between healthy men and women. In this study, 60 participants (30 males, 30 females) dropped from a height of 43 cm. A digital camera and two-dimensional video motion analysis software were used to analyze the kinematic data. There was significant difference in the mean knee valgus angle at initial contact landing between the two groups (Mean=, SD= in males, Mean=, SD= in females). The range of knee valgus angle on landing (Mean=, SD= in males, Mean=, SD= in females) was differed significantly (p<.05). The maximal angle of knee valgus on landing (Mean=, SD= in males, Mean=, SD= in females) was also differed significantly (p<.05). The females landed with a larger range of knee valgus motion than the males and this might have increased the likelihood of a knee injury. The absence of dynamic knee joint stability may be responsible for increased rates of knee injury in females. No method for accurate and practical screening and identification of athletes at increased risk of ACL injury is currently available to target those individuals that would benefit from neuromuscular training before sports participation.

The purpose of this study was to investigate the effect of donning of a hard insole in patients with hallux valgus. Fourteen subjects were selected from patient with foot pain at Lee Chang-Heon Foot Clinic from August 4, 2000 to September 15, 2000. The hallux valgus angle and the first-second intermetatarsal angle were radiographically measured before and after donning the hard insole. Based on these two kinds of angles, a mild hallux valgus deformity group was characterized by the hallux valgus angle of less than 20 degrees, and a moderate hallux valgus deformity group was characterized by the hallux valgus angle of 20 to 40 degrees. After three weeks with the hard insole donned, the foot angles of the patients with hallux valgus were measured again. The data were analyzed by Wilcoxon signed ranks test, and the following results were obtained: 1) After the trial, both mild hallux valgus deformity group and moderate hallux valgus deformity group demonstrated that the hallux valgus angles were significantly decreased. 2) After the trial, mild hallux valgus deformity group demonstrated that the first-second intermetatarsal angle was significantly decreased. 3) After the trial, moderate hallux valgus deformity group demonstrated that the first-second intermetatarsal angle was not significantly decreased. The above findings revealed that according to donning hard insole, the hallux valgus angles of mild and moderate hallux valgus deformity groups and the first-second intermetatarsal angle of mild hallux valgus deformity group were significantly decreased. The results of this study have some limitation for generalization due to the limited number of subjects. Further studies are needed to evaluate the effect of hard insole on hallux valgus with more precise laboratory equipments and measurements in patients with hallux valgus.