Effect of short foot exercise on lower-limb motor control function during single-leg standing in university students with flatfoot: A randomized controlled trial.

INTRODUCTION: Intrinsic foot muscles (IFMs) play an important role in lower-limb motor control, including biomechanics and neuromuscular control function. Short foot exercise (SFE) and toe curl exercise (TC) are methods used to train the IFMs, but their effect on lower-limb motor control has not been reported in previous studies. This study evaluated the effects of SFE and TC on lower-limb motor control function during single-leg standing (SLS). TRIAL DESIGN: Randomized control trial. METHOD: Thirty-six participants with flatfoot were randomly assigned to the SFE or TC group and performed exercise for 8 weeks. The assessment items were navicular drop test, toe grip strength (TGS), plantar sensation, and SLS. In the SLS assessment, we measured the mean center of pressure (COP) amplitude in the anteroposterior (AP) and mediolateral (ML) directions, onset time of gluteus maximus (G. max) and gluteus medius (G. med), angle of forefoot/hindfoot protonation and hip adduction, and lateral pelvic shift. Mixed-model repeated-measures analysis of variance and Bonferroni corrections were performed in statistical analysis. RESULTS: The SFE group showed significant differences between pre- and post-intervention for TGS (p < 0.001), COP ML (p = 0.039), and onset times of G. max (p = 0.015), and G. med (p < 0.001). The TC group showed no significant differences in all assessment items. CONCLUSION: Our finding suggests that SFE contributes to lower neuromuscular control function in people with flatfoot. TRIAL REGISTRATION: UMIN000049963.

The combined effect of short foot exercises and orthosis in symptomatic flexible flatfoot: a randomized controlled trial.

BACKGROUND: Flatfoot is a musculoskeletal problem associated with dysfunctional active and passive supporting structures of the normal foot curvature. Strengthening of the intrinsic foot muscles or using shoe orthosis are recommend treatment approaches. However, investigating the effect of combining both approaches is still warranted. AIM: To examine the effect of applying short foot exercises (SFE) combined with shoe insole versus shoe insole alone on foot pressure measures, pain, function and navicular drop in individuals with symptomatic flexible flatfoot. DESIGN: Prospective, active control, parallel-group, assessor-blinded, randomized controlled trial and intention-to-treat analysis. SETTING: Outpatient physical therapy clinic of a university teaching hospital. POPULATION: Forty participants with symptomatic flexible flatfoot. METHODS: A six-week treatment protocol of SFE (three sets of 10 repetitions a day) in addition to shoe insole (eight hours a day) (experimental group, N.=20) or shoe insole only (eight hours a day) (control group, N.=20). Clinic visits were made at baseline and every two weeks for monitoring and follow-up. The static and dynamic foot area, force and pressure measures, pain, lower extremity function, and navicular drop were assessed at baseline and postintervention. RESULTS: Forty participants joined the study and 37 (92.5%) completed the six-week intervention period. Foot pressure, pain and function showed a significant interaction (P=0.02 - <0.001) and time (P<0.001) effects with a non-significant group effect in favor of the experimental group. Post-hoc analysis revealed that the experimental group had lesser pain (P=0.002) and better function (P=0.03) than the control group at six weeks. Navicular drop decreased equally in both groups. CONCLUSIONS: Implementation of shoe insole and SFE for six weeks improved pain and function and altered foot pressure distribution greater than shoe insole alone in patients with symptomatic flatfoot. CLINICAL REHABILITATION IMPACT: Wearing shoe insole is an easy, but passive, treatment approach for a flatfoot problem. This study provided evidence regarding the added benefit of SFE. It is recommended that rehabilitation practitioners implement a comprehensive treatment protocol including both shoe insole and SFE for at least six weeks to achieve better results for their flatfoot patients.

Does the long-term use of medial arch support insole induce the radiographic structural changes for pediatric flexible flat foot? - A prospective comparative study.

BACKGROUND: Several conservative treatment methods, from intrinsic muscle exercises to orthoses, including insoles or specially designed shoes, have been introduced for pediatric flexible flat foot (PFFF). However, the structural effects of a long-term use of medial arch support insole remain unclear because the normal physiological maturation of the medial longitudinal arch cannot be ruled out. METHODS: From January 2005 to June 2015, 18 patients (34 feet) in group 1 (continuously insole applied group) and 13 patients (26 feet) in group 2 (untreated group) were enrolled. Medial arch support insole was applied from the age 10-11years to radiographic physeal closure. RESULTS: In group 1, talonavicular coverage angle, lateral talo-1st metatarsal angle, calcaneal pitch angle and medial cuneiform height were significantly changed at final follow-up, although all values were still within the abnormal range. Further, no significant differences were found in any of the increments of the radiographic parameters between group 1 and 2. CONCLUSIONS: Radiographic improvements were found in both of medial arch support insole treated or untreated group despite all radiographic values were still within the abnormal range. It was meaningful that the PFFF could be improved somewhat until the physes were closed. And the hindfoot alignment remained unchanged regardless of medial arch support insole application.

Effects of plantar intrinsic foot muscle strengthening exercise on static and dynamic foot kinematics: A pilot randomized controlled single-blind trial in individuals with pes planus.

BACKGROUND: No reliable evidence has confirmed whether plantar intrinsic foot muscle strengthening exercises improve static and dynamic foot kinematics in individuals with pes planus. RESEARCH QUESTION: Does the short-foot exercise affect static foot alignment and foot kinematics during gait in individuals with pes planus? METHODS: This was a randomized controlled single-blind trial involving 20 participants with pes planus who were randomly allocated to a short-foot exercise group (exercise) or a control group (controls). Exercise patients performed a progressive short-foot exercise three times per week for 8 weeks; controls received no intervention. Before and after the 8-week intervention, foot kinematics during gait, including dynamic navicular drop-the difference between navicular height at heel strike and the minimum value-and the time at which navicular height reached its minimum value were assessed, using three-dimensional motion analysis. We assessed static foot alignment by foot posture index and navicular drop test, and the thickness of the intrinsic and extrinsic foot muscles using ultrasound. All measurements were performed by one investigator (KO) blinded to the participants' allocation. RESULTS: After the 8-week intervention in the exercise group, foot posture index scores with regard to calcaneal inversion/eversion improved significantly (p < 0.05). Moreover, the time required for navicular height to reach the minimum value decreased significantly (p < 0.01). SIGNIFICANCE: For individuals with pes planus, the short-foot exercise effectively corrected static foot alignment and temporal parameters of foot kinematics during gait. This temporal change, which shortens the time for navicular height to reach its minimum value, indicates an improved windlass mechanism. Therefore, short-foot exercise might effectively prevent or treat injuries related to the pes planus alignment.

Foot orthoses alter lower limb biomechanics but not jump performance in basketball players with and without flat feet.

BACKGROUND: Flat-footed individuals are believed to have poorer jump performance compared to normal-arched individuals. Foot orthoses are commonly used to support the deformed foot arch, and improve normal foot function. However, it is unclear if foot orthoses use affects jump performance in athletes. Our study aims to investigate if foot type and/or foot orthosis influence countermovement jump (CMJ) and standing broad jump (SBJ) performance and lower limb biomechanics. METHODS: Twenty-six male basketball players were classified into normal-arched (n = 15) or flat-footed (n = 11) groups using the Chippaux-Smirak index, navicular drop test, and the resting calcaneal angle measurement. They performed jumps with and without prefabricated foot orthoses. We measured jump height and distance for CMJ and SBJ, respectively. Hip, knee and ankle joint angles, angular velocities, moments and powers during take-off were also measured. RESULTS: For CMJ, the flat-footed group exhibited less ankle plantarflexion (F 1,24 = 8.407, p = 0.008, η p 2 = 0.259 large effect) and less hip joint power (F 1,24 = 7.416, p = 0.012, η p 2 = 0.244 large effect) than the normal-arched group. Foot orthoses reduced ankle eversion in both groups (F 1,24 = 6.702, p = 0.016, η p 2 = 0.218 large effect). For SBJ, the flat-footed group produced lower peak hip angular velocity (F 1,24 = 7.115, p = 0.013, η p 2 = 0.229 large effect) and generated lower horizontal GRF (F 1,24 = 5.594, p = 0.026, η p 2 = 0.189 large effect) than the normal-arched group. Wearing foot orthoses reduced ankle eversion (F 1,24 = 5.453, p = 0.028, η p 2 = 0.185 large effect), peak horizontal GRF (F 1,24 = 13.672, p = 0.001, η p 2 = 0.363 large effect) and frontal plane ankle moment (F 1,24 = 4.932, p = 0.036, η p 2 = 0.170 large effect). CONCLUSION: Foot type and the use of foot orthoses influence take-off biomechanics, but not actual CMJ and SBJ performances in basketball players. Compared to the normal-arched individuals, flat-footed athletes generated smaller propulsion GRF and lower hip flexion velocity and power, which suggests possible compensatory movement strategies to maximise jump performance. Future studies may investigate whether these altered biomechanics, taking into consideration their respective magnitude and effect sizes, may have implications on lower limb injuries. The use of foot orthoses resulted in biomechanical changes in both the normal-arched and flat-footed groups but does not enhance jumping performance.

The effect of different foot orthoses on pain and health related quality of life in painful flexible flat foot: a randomized controlled trial.

BACKGROUND: Foot orthoses are widely used in conservative treatment of painful flexible flatfoot (PFFF) however research is limited to choose the best option in orthotic treatment. AIM: We aimed to compare the effects of computer-aided design/computer-aided manufacturing (CAD-CAM) and conventional insole types in comparison with sham insole, on pain and health related quality of life in patients with PFFF. DESIGN: Randomized controlled trial. SETTING: Outpatient rehabilitation clinic. POPULATION: Sixty-seven people with PFFF, aged between 18 and 45 years, were assigned to CAD-CAM (N.=22), conventional (N.=22) or sham (N.=23) groups. METHODS: In addition to insoles, a home-based exercise program was followed by all participants for eight weeks. Foot pain intensity and quality of life were assessed at the initial evaluation and at the end of two-month follow-up. RESULTS: Pain intensity (Mean±SD, mm on VAS) was significantly lower in CAD-CAM (27.84±18.41) and conventional (27.05±16.82) insole groups than sham group (46.39±20.18) after two months (P<0.05), but there was no difference between conventional and CAD-CAM (P>0.05). All groups had significantly higher physical health scores at the second assessment (P<0.05), but there was no intergroup difference (P>0.05). CONCLUSIONS: CAD-CAM and conventionally designed insoles are both more effective than having sham insole in alleviating pain in PFFF. CLINICAL REHABILITATION IMPACT: CAD-CAM and conventionally designed semicustom insoles in conjunction with a home-based exercise program are both effective in controlling pain compared with sham insole and exercise in PFFF. Clinicians can prescribe both types of semicustom insoles as a part of conservative treatment instead of each other.

Effects of selective strengthening of tibialis posterior and stretching of iliopsoas on navicular drop, dynamic balance, and lower limb muscle activity in pronated feet: A randomized clinical trial.

Objectives: Flexibility and strength are compromised in pronated feet, which could in turn lead to alteration of the dynamic balance and muscle activity in the lower extremities. This study aimed to analyze the effects of selective tibialis posterior strengthening and iliopsoas stretching on navicular drop, dynamic balance, and lower limb muscle activity in young adults with pronated feet. Methods: Twenty-eight participants with pronated feet were randomly assigned to either the stretching and strengthening group (n = 14) or the conventional exercise group (n = 14). The stretching and strengthening group performed tibialis posterior strengthening exercises and iliopsoas stretching three times a week for 6 weeks in addition to the conventional towel curl exercises. The conventional exercise group performed towel curl exercises only. Navicular drop, dynamic balance, and lower limb muscle activity were assessed at baseline and post-intervention. A mixed model analysis of variance was performed to test the study hypothesis. Results: Significant group effects for the activity of tibialis anterior (p = 0.003) and abductor hallucis muscle (p = 0.010), as well as for the posterolateral (p = 0.036) and composite reach scores (p = 0.018), were detected. Significant group × time interactions were observed for naviculardrop (p < 0.001), all dynamic balance components (p < 0.001), and the activity of tibialis anterior (p < 0.001) and abductor hallucis (p < 0.001). Conclusions: This study demonstrated that inclusion of selective tibialis posterior strengthening and iliopsoas stretching in addition to the conventional towel curl exercise program could improve important clinical outcomes, such as navicular drop, muscle activity, and dynamic balance in flatfeet.

The effect of additional activation of the plantar intrinsic foot muscles on foot kinematics in flat-footed subjects.

BACKGROUND: Strengthening exercises of the plantar intrinsic foot muscles (PIFMs) are often prescribed to flat-footed subjects because of the capacity of the PIFMs to support the medial longitudinal arch (MLA). However, it is unclear whether the capacity of the PIFMs to support the MLA is enough to change the foot kinematics in flat-footed subjects. To confirm this, the current study examined changes in foot kinematics in flat-footed subjects during standing and gait accompanied by changes in the activity of the PIFMs. METHODS: Eighteen flat-footed subjects were randomly assigned to an electrical stimulation group (ESG) or a control group (CG). In the ESG, electrical stimulation to the PIFMs was applied during standing and gait to simulate reinforcement of the PIFMs. Then, foot kinematics were measured using 3D motion analysis, and the amount of change from baseline (when no electrical stimulation was applied) was compared between the groups. RESULTS: In the gait analysis, the time at which the MLA height reached its minimum value was significantly later in the ESG, with no reduction in the MLA height at that time. Moreover, forefoot inversion angle and tibial external rotation angle were significantly increased in the ESG at that time. In the standing analysis, there were no significant differences between the groups. CONCLUSION: The results revealed that in flat-footed subjects, the PIFMs have the capacity to support the MLA enough to change foot kinematics during gait. Strengthening these muscles may be effective in preventing or treating lower extremity overuse injuries related to flat-foot alignment.

Acute effect of foot orthoses on frequency domain of ground reaction forces in male children with flexible flatfeet during walking.

BACKGROUND: Flatfoot is a structural and functional abnormality of the foot that may cause lower limb mechanical damage during walking. The aim of this study was to investigate the acute effect of foot orthoses on the frequency domain of ground reaction forces in children with flatfeet during the stance phase of walking. METHODS: Bilateral gait data were collected from fifteen male children suffering from flatfeet syndrome. Two Kistler force platforms were used to record the ground reaction forces of each limb during level walking. Arc support foot orthoses were used as an intervention. RESULTS: No significant differences in the frequency content of the dominant limb ground reaction forces were found in the three directions in the two conditions (P>0.05). However, the use of foot orthoses decreased non-dominant limb medio-lateral ground reaction force frequency with a power of 99.5% (P=0.015). Overall, for both limbs, the amplitude of the three-dimensional ground reaction force components during walking with foot orthoses were lower than those obtained without foot orthoses (P<0.05). For both dominant and non-dominant limbs, the essential number of harmonics in three directions during walking with and without foot orthoses were similar (P>0.05). CONCLUSIONS: Foot orthoses decreased medio-lateral ground reaction force frequency in the non-dominant limb, but have little effect on other ground reaction frequency components. Decreased frequency phenomena due to foot orthoses in children with flatfeet suggest an attenuation of ground reaction forces during walking. Frequency domain analysis thus offered new insights on the gait improvements associated with using foot orthoses.

Use of high speed stereo radiography to assess the foot orthoses effectiveness in controlling midfoot posture during walking: A pilot study.

BACKGROUND: The intent of this pilot study was to determine the feasibility of using high-speed stereo radiography (HSSR) to assess the effectiveness of footwear and foot orthoses in controlling the change in the position of the midfoot during walking in individuals with a flexible pes planus foot type. METHODS: Four individuals (1 female; 3 male) with a mean age of 25 years (range 22-29) and a bilateral flexible pes planus foot type participated in the study. The HSSR system was used to measure 3-dimensional changes in the longitudinal arch angle (LAA) with each participant walking barefoot, shoe only and shoes with orthoses. RESULTS: The HSSR system was found to be highly effective in measuring the change in the position of the midfoot, as measured using the LAA, when wearing footwear with or without foot orthoses. Based on an assessment of mean values, three out of the four participants demonstrated a change in the LAA as a result of using either shoes only or shoes with orthoses. The methodology used in this pilot study for assessing the effect of footwear and foot orthoses on the posture of the midfoot was highly effective with no side-effects noted by any of the study participants. CONCLUSIONS: Future studies using the HSSR will require modifications to participant inclusion criteria as well as alterations to the data collection methodology. The HSSR system used in this study is feasible for use in larger cohort studies assessing footwear and foot orthosis effectiveness with the described modifications.

Effect of total-contact orthosis on medial longitudinal arch and lower extremities in flexible flatfoot subjects during walking.

BACKGROUND: Total-contact orthosis (TCO) is one kind of foot orthosis (FO) that is used to adjust biomechanics in flexible flatfoot. OBJECTIVE: To determine the effects of a TCO on the MLA moment, MLA deformation angle and lower limb biomechanics. STUDY DESIGN: Cross-sectional study. METHODS: Seven-flatfoot and thirteen-normal foot subjects were recruited by footprint and radiographs. The biomechanics of subjects with normal foot (NF), flatfoot with shoe only (FWOT) and flatfoot with TCO (FWT) were collected in a 3D motion analysis laboratory and force plates. The MLA and lower limb biomechanics in each condition during specific sub-phases of stance were analyzed. RESULTS: The NF had larger MLA eversion moment after shod walking ( p = 0.001). The FWT condition compared with the FWOT condition had a significantly larger peak MLA upward moment ( p = 0.035) during pre-swing, larger peak knee external rotation angle ( p = 0.040) during mid stance, smaller peak knee extension moment during terminal stance ( p = 0.035) and a larger ground reaction force in the anterior-posterior direction during early stance ( p < 0.05). CONCLUSION: Our study found positive effects from the customized TCOs which included an increased TCO angle that led to a decreased peak MLA moment in the frontal plane in flexible flatfoot subjects during walking. Clinical relevance Lower limb biomechanics is different from normal in subjects with flexible flatfoot. The design of a TCO affects MLA, ankle and knee biomechanics and may be used to clinically correct biomechanical changes in flexible flatfoot.

Comparison of plantar pressure distribution in CAD-CAM and prefabricated foot orthoses in patients with flexible flatfeet.

BACKGROUNDS: The effect of foot orthoses on plantar pressure distribution has been proven by researchers but there are some controversies about advantages of custom-made foot orthoses to less expensive prefabricated foot orthoses. METHODS: Nineteen flatfeet adults between 18 and 45 participated in this study. CAD-CAM foot orthoses were made for these patients according to their foot scan. Prefabricated foot orthoses were prepared according to their foot size. Plantar pressure, force and contact area were measured using pedar®-x in-shoe system wearing shoe alone, wearing CAD-CAM foot orthoses and wearing prefabricated foot orthoses. Repeated measures ANOVA model with post-hoc, Bonferroni comparison were used to test differences. RESULTS: CAD-CAM and prefabricated foot orthoses both decreased pressure and force under 2nd, 3-5 metatarsal and heel regions comparing to shoe alone condition. CAD-CAM foot orthosis increased pressure under lateral toe region in comparison to shoe alone and prefabricated foot orthosis. Both foot orthoses increased pressure and contact area in medial midfoot region comparing to shoe alone condition. Increased forces were seen at hallux and lateral toes by prefabricated foot orthoses in comparison with CAD-CAM foot orthoses and control condition, respectively. CONCLUSION: According to the results, both foot orthoses could decrease the pressure under heel and metatarsal area. It seems that the special design of CAD-CAM foot orthoses could not make great differences in plantar pressure distribution in this sample. Further research is required to determine whether these results are associated with different scan systems or design software.

The Effect of Arch Height and Material Hardness of Personalized Insole on Correction and Tissues of Flatfoot.

Flat foot is one of the common deformities in the youth population, seriously affecting the weight supporting and daily exercising. However, there is lacking of quantitative data relative to material selection and shape design of the personalized orthopedic insole. This study was to evaluate the biomechanical effects of material hardness and support height of personalized orthopedic insole on foot tissues, by in vivo experiment and finite element modeling. The correction of arch height increased with material hardness and support height. The peak plantar pressure increased with the material hardness, and these values by wearing insoles of 40° were apparently higher than the bare feet condition. Harder insole material results in higher stress in the joint and ligament stress than softer material. In the calcaneocuboid joint, the stress increased with the arch height of insoles. The material hardness did not apparently affect the stress in the ankle joints, but the support heights of insole did. In general, insole material and support design are positively affecting the correction of orthopedic insole, but negatively resulting in unreasonable stress on the stress in the joint and ligaments. There should be an integration of improving correction and reducing stress in foot tissues.

Effect of foot orthoses on the medial longitudinal arch in children with flexible flatfoot deformity: A three-dimensional moment analysis.

Foot orthoses are often used to correct altered gait patterns. The purpose of this study was to investigate how foot orthoses can modify the magnitude of three dimensional moments of ankle, knee, and hip joints during a stride of gait in children with flexible flat feet. Bilateral gait data were collected from fourteen male children (age 10.2±1.4 years) suffering from flat feet syndrome. In order to obtain the kinematics data, a Vicon system with six cameras (100Hz) was used and two Kistler force plates (1000Hz) to record the kinetics data under each leg. Arc support foot orthoses were used as an intervention. Paired-sample T-test was used for within-group comparisons (α=0.05). The results of data analysis showed that foot orthoses can decrease the ankle evertor moment, knee and hip abductor moments and hip flexor moment in dominant lower limb. In non-dominant lower limb, using the orthoses can decrease evertor and internal rotator moments at the ankle, flexor and internal rotator moments at the knee and extensor moment at the hip, while it can increase dorsiflexor moment at the ankle. The findings imply that effects of orthoses on three dimensional moments differ in dominant and non-dominant lower limbs. Furthermore, results demonstrated that dominant and non-dominant lower limbs would also show different responses to the same intervention.

Adult-acquired flatfoot deformity.

Adult-acquired flatfoot deformity (AAFD) is a known and recognized cause of pain and disability. Loss of PTT function is the most important contributor to AAFD, and its estimated prevalence is thought to be over 3%. This review aims to summarize the current literature and encompass recent advances regarding AAFD.

Shod wear and foot alignment in clinical gait analysis.

Sagittal plane alignment of the foot presents challenges when the subject wears shoes during gait analysis. Typically, visual alignment is performed by positioning two markers, the heel and toe markers, aligned with the foot within the shoe. Alternatively, software alignment is possible when the sole of the shoe lies parallel to the ground, and the change in the shoe's sole thickness is measured and entered as a parameter. The aim of this technical note was to evaluate the accuracy of visual and software foot alignment during shod gait analysis. We calculated the static standing ankle angles of 8 participants (mean age: 8.7 years, SD: 2.9 years) wearing bilateral solid ankle foot orthoses (BSAFOs) with and without shoes using the visual and software alignment methods. All participants were able to stand with flat feet in both static trials and the ankle angles obtained in BSAFOs without shoes was considered the reference. We showed that the current implementation of software alignment introduces a bias towards more ankle dorsiflexion, mean=3°, SD=3.4°, p=0.006, and proposed an adjusted software alignment method. We found no statistical differences using visual alignment and adjusted software alignment between the shoe and shoeless conditions, p=0.19 for both. Visual alignment or adjusted software alignment are advised to represent foot alignment accurately.

Do corrective shoes improve the development of the medial longitudinal arch in children with flexible flat feet?

BACKGROUND: Flexible flatfoot, as the most prevalent foot deformity in pediatric population still has no standardized strategy for its management hence some orthopedic surgeons have the tendency to use orthotic devices. The objective of this study is to evaluate whether orthotic shoes effect the natural course of the developing medial longitudinal arch in children diagnosed with moderate flexible flatfoot. METHODS: Fourty-five children (33 boys and 12 girls) with moderate flexible flatfoot were enrolled in this study. They were followed up for 34.6 ± 10.9 months (24-57 months). Patients in group 1 were treated with corrective shoes whereas group 2 was left untreated. Patients were evaluated according to; general joint laxity, arch index, lateral talo-first metatarsal (TM), talo-horizontal (TH), calcaneal pitch (CP), lateral and anterior talocalcaneal (TC) angles. RESULTS: Although there was a significant decrease in general laxity in both groups, decrease of laxity percentage was not significant between groups (p = 0.812). TM, TH and anterior TC angles were found to be decreased in groups whereas there was no difference between group 1 and 2. The arch index was found to be correlated with TM and TH angles in both groups (p = 0.004, p = 0.013). CONCLUSIONS: Corrective shoes for flexible flatfoot was found not effective on development of foot arches. Therefore, they should be limited only for selected cases.

Comparing the immediate effects of UCBL and modified foot orthoses on postural sway in people with flexible flatfoot.

BACKGROUND: Different types of foot orthoses have been prescribed for patients with flatfoot. Results of several studies have shown that orthoses were able to change balance parameters in people with flatfoot. However, the possible effect of orthosis flexibility on balance has not yet been investigated. OBJECTIVES: The aim of the current study was to investigate the immediate effect of a rigid University of California Berkeley Laboratory (UCBL) foot orthosis, a modified foot orthosis, and a normal shoe on the postural sway of people with flexible flatfoot. STUDY DESIGN: Quasi-experimental. METHODS: In all, 20 young adults with flatfoot (aged 23.5 ± 2.8 years) were invited to participate in this study. The Biodex Stability System was employed to perform standing balance tests under three testing conditions, namely, shoe only, UCBL, and modified foot orthosis. Total, medial-lateral, and anterior-posterior sway were evaluated for each condition. RESULTS: The results of this study revealed no statistical difference in the medial-lateral and anterior-posterior stability indices between foot orthoses and shoed conditions. The overall stability index with the UCBL foot orthosis, however, was significantly lower than that with the modified foot orthosis. CONCLUSION: The UCBL foot orthosis was able to decrease total sway and improve balance in people with flexible flatfoot. CLINICAL RELEVANCE: Results of previous studies have indicated that foot orthoses were able to affect the balance of people with flatfeet. However, the possible effects of flexible orthoses on balance have not been examined. The results of this study may provide new insight into material selection for those people with balance disorders.

Revisión del tratamiento del pie plano adquirido del adulto en el estadio II / Treatment of adult acquired flatfoot stage II: a literature review

El pie plano adquirido del adulto es una patología compleja resultado de la insuficiencia del tendón tibial posterior y del fallo de las estructuras capsulares y ligamentosas del pié. En el estadio II existe una gran controversia respecto al tratamiento a elegir. Se ha realizado una revisión bibliográfica narrativa mediante el motor de búsqueda de Pubmed. La búsqueda se ha acotado a las publicaciones realizadas durante los últimos cinco años. Se han seleccionado 30 artículos que incluyen el pie plano adquirido en su conjunto y el estadio II. Los autores coinciden que el tratamiento conservador debe ser siempre la primera opción. En caso de cirugía debemos de valorar de manera independiente la corrección del valgo del retropié, siendo la osteotomía de medialización de calcáneo el tratamiento más extendido; el alargamiento de la columna externa; la inestabilidad de la columna medial; la supinación del antepié; y la presencia de equinismo. Cada paciente presenta una deformidad característica por lo que el tratamiento debe ser individualizado

Adult acquired flatfoot deformity is a complex pathology consisting both of posterior tibial tendon insufficiency and failure of the capsular and ligamentous structures of the foot. In stage II there is much controversy when it comes to treatment. We performed a narrative literature review using the PubMed search engine. The search was limited to publications over the past five years. We have selected 30 articles including acquired flatfoot a whole and stage II. The authors agree that conservative treatment should always be the first choice. When we decide surgical treatment independently assess the correction of the hindfoot valgus, medializing calcaneal osteotomy is the most accepted treatment; lengthening the lateral column; the instability of the medial column; supination of the forefoot; and the presence of equinus. Each patient has a characteristic deformity so the treatment must be individualized