The effectiveness of rearfoot medial wedge intervention on balance for athletes with chronic ankle instability

Postural Control Deficits During Static Single-leg Stance in Chronic Ankle Instability: A Systematic Review and Meta-Analysis

CONTEXT

Postural control deficits arising from injured ankles are central to chronic ankle instability (CAI) and its persistent symptoms. This is usually measured by recording the center of pressure (CoP) trajectory during static single-leg stance using a stable force plate. However, existing studies have produced conflicting results on whether this mode of measurement adequately reveals the postural deficits in CAI.

OBJECTIVE

To determine whether postural control during static single-leg stance is impaired in CAI patients when compared with uninjured healthy controls.

DATA SOURCES

Literature databases, PubMed, Embase, Web of Science, Cochrane Library, Scopus, CINAHL, and SPORTDiscus, were searched from inception to April 1, 2022, using ankle-, injury-, and posture-related terms.

STUDY SELECTION

Two authors independently performed the step-by-step screening of article titles, abstracts, and full texts to select peer-reviewed studies investigating CoP trajectory during static single-leg stance using a stable force plate in CAI patients and healthy controls. A total of 13,637 studies were reviewed, and 38 studies (0.003%) met the selection criteria.

STUDY DESIGN

Meta-analyses of descriptive epidemiological study.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

CoP parameters, sway directions, visual condition, and numerical data (means and standard deviations) were extracted.

RESULTS

The injured ankles of CAI patients had higher standard deviations of sway amplitude in both anterior-posterior and medial-lateral directions (standardized mean difference [SMD] = 0.36 and 0.31, respectively) under conditions of open eyes than controls. Higher mean sway velocity in anterior-posterior, medial-lateral, and total directions (SMD = 0.41, 0.37, and 0.45, respectively) with closed eyes was also found.

CONCLUSION

CAI patients had deficits of postural control during static single-leg stance, and these deficits were identified by the CoP trajectory. Further methodological explorations of CoP parameters and corresponding test conditions are required to enhance the sensitivity and reliability of postural deficit assessments in CAI using force plates.

Does medial calcaneal wedge improve static balance and load distribution in young adults with pronated foot?

BACKGROUND

Foot orthoses changing the momentum in the subtalar joint are often recommended, especially in activities loading the foot, to bring the pronated foot posture closer to neutral.

OBJECTIVES

To examine the immediate effect of medial heel wedge on static balance and load distribution in patients with increased pronation in the foot.

STUDY DESIGN

Experimental study design.

METHODS

Forty people with right dominant lower extremity participated in the study. For static balance assessment, we assessed ellipse surface, sway length, x-y mean, AP index, and Romberg ratio on 1 foot and measured load distribution as right-left foot and fore-hind foot with and without wedge.

RESULTS

There was a difference between the parameters of the ellipse surface and the Romberg ratio on the left side in the measurements performed with and without wedge for static balance on the left side ( P < 0.05) while there was no difference in the remaining values ( P > 0.05). In the load distribution, the change in the right anteroposterior foot was significant, increasing the load on the forefoot with the wedge ( P < 0.05) while we observed no difference in the left fore-hind foot load distribution and right-left foot load distribution ( P > 0.05).

CONCLUSION

Our study showed that for static balance, medial wedge can improve balance on the left side by decreasing sway, and for load distribution, the medial wedge changed the load distribution from back to front on the right side. These small differences in young healthy individuals are a preliminary indication that further studies are needed.

Impact of in shoe and barefoot placed frontal wedges on plantar loading: A systematic review

PURPOSE

The main aim of this review is to report the effect of different types of in-shoe and barefoot wedges on the distribution of the plantar loading of the human foot. We hypothesise that frontal plane wedges modify this parameter.

METHODS

A systematic review was performed, using the PubMed, CINAHL, Prospero and Scopus databases, consulted from their date of first publication to May 2020. Only observational (cross-over studies), randomised controlled trials (RCTs) and quasi-experimental studies addressing the effects of in-shoe and barefoot frontal plane wedges on plantar loading were included. All articles were subjected to quality assessment, using the Newcastle-Ottawa scale for the observational (cross-over) studies, TREND for quasi-experimental studies and the Cochrane Collaboration's tool for the RCTs.

RESULTS

Eleven papers were included in the final review. Four were cross-over studies, other four were quasi-experimental studies and three were RCTs. These eleven studies included 320 patients, with ages ranging from 20 to 60 years. Regarding the risk of bias, most of the observational studies and RCTs had a moderate level of quality.

CONCLUSIONS

The results suggest that lateral wedges are more effective, producing a lateral shift of the centre of pressure and increasing the pressure. Regarding the impact on the peak impact force there seems to be less consensus among the published data.

Plantar pressure distribution during running with a self-customized foot orthosis in a home microwave

The individualization of a custom-made foot orthosis could provide improvements in plantar loading distribution regarding a prefabricated one. However, not all runners can afford it because of its high cost. A new type of low-cost prefabricated foot orthoses with self-customization could be the solution. The aim of the study was to evaluate if self-customized prefabricated foot orthoses (SCFO) could improve plantar pressure distribution with respect to generic prefabricated ones without customization, during the intense prolonged running. Thirty healthy recreational runners performed two tests of 30 min running on a treadmill, each one with a foot orthosis condition, on different days. Mean peak pressure, pressure-time integral, relative pressure and stance time were measured at the beginning and at the end of the tests. Plantar pressure data were analyzed in nine foot regions. Two-way repeated-measures ANOVAs were performed. SCFO reduced relative pressure in metatarsals (P < 0.005) and lateral heel (P = 0.004), thanks to a greater involvement of arch area in mean peak pressure (medial: P = 0.006 and lateral: P = 0.019) and relative pressure (P < 0.001). In general, prolonged run increased pressures in forefoot, in both foot orthosis, but with lower values in metatarsals with SCFO (P < 0.022), which also helped reduce relative pressure in midfoot (P = 0.007) and medial heel (P = 0.035). Stance time was not modified in any case (P > 0.05). In conclusion, customization and better fit of a low-cost prefabricated foot orthosis can improve plantar pressure distribution during a prolonged run, being a good prevention mechanism for plantar overloading in healthy runners.

The Effects of a Medial Heel Wedge on the Weight-Bearing Response of Hindfoot Valgus and the Total Weight-Bearing Responses of the Navicular and Talus Bones

OBJECTIVES Medial heel wedges are commonly prescribed to manage the weight-bearing response of hindfoot valgus and the total weight-bearing responses of the navicular and talus bones. Previous studies have reported that a medial heel wedge is effective in the management of musculoskeletal injuries. However, it remains unclear the effect of a medial heel wedge on the weight-bearing responses of footarch bones in vivo. To clarify the effects of a medial heel wedge on the weight-bearing response of hindfoot valgus and the total weight-bearing responses of the navicular and talus bones is necessary to understand how best to treat musculoskeletal injuries clinically. The purpose of our study was to clarify the effects of a medial heel wedge on the weight-bearing response of hindfoot valgus and the total weight-bearing responses of the navicular and talus bones.METHODS Twenty-five healthy males were analyzed. We obtained MRI scanning of the right foot under non-loading (NL) and full weight-bearing (FW) conditions. Participants wore two insole types, a flat insole and a medial heel wedge. To evaluate the weight-bearing response in hindfoot valgus, the hindfoot alignment view (HAV) was measured. We also measured navicular and talus bone positions and calculated the total positional changes of the navicular and talus bones (ΔTPCN, ΔTPCT) from the vertical and medial displacements using the Pythagorean theorem.RESULTS Significant interactions were observed with the HAV. Under both NL and FW conditions, the HAV was smaller on the medial heel wedge than on the flat insole. In addition, the ΔTPCN was significantly smaller on the medial heel wedge than on the flat insole. However, no significant differences were observed for ΔTPCT.CONCLUSIONS Our results suggest that use of a medial heel wedge decreases hindfoot valgus values under both NL and FW conditions and stabilizes the total weight-bearing response of the navicular bone.