Limits...
Mechanism of orthotic therapy for the painful cavus foot deformity.

Najafi B, Wrobel JS, Burns J - J Foot Ankle Res (2014)

Bottom Line: Custom-made foot orthoses (CFO) have been shown to be an effective treatment option, but their specificity is unclear.No relationship between change in pressure magnitude and change in symptoms was found in either group.Our data suggest that a primary function of effective orthotic therapy with CFO is redistribution of abnormal plantar pressures.

View Article: PubMed Central - HTML - PubMed

Affiliation: Interdisciplinary Consortium on Advanced Motion Performance (iCAMP), Southern Arizona Limb Salvage Alliance (SALSA), University of Arizona College of Medicine, Tucson, AZ, USA. najafi.bijan@gmail.com.

ABSTRACT

Background: People who have extremely high arched feet or pes cavus often suffer from substantial foot pain. Custom-made foot orthoses (CFO) have been shown to be an effective treatment option, but their specificity is unclear. It is generally thought that one of the primary functions of CFO is redistributing abnormal plantar pressures. This study sought to identify variables associated with pain relief after CFO intervention.

Methods: Plantar pressure data from a randomized controlled trial of 154 participants with painful pes cavus were retrospectively re-analyzed at baseline and three month post CFO intervention. The participants were randomized to a treatment group given CFO or a control group given sham orthoses.

Results: No relationship between change in pressure magnitude and change in symptoms was found in either group. However, redistribution of plantar pressure, measured with the Dynamic Plantar Loading Index, had a significant effect on pain relief (p = 0.001). Our final model predicted 73% of the variance in pain relief from CFO and consisted of initial pain level, BMI, foot alignment, and changes in both Dynamic Plantar Loading Index and pressure-time integral.

Conclusion: Our data suggest that a primary function of effective orthotic therapy with CFO is redistribution of abnormal plantar pressures. Results of this study add to the growing body of literature providing mechanistic support for CFO providing pain relief in painful foot conditions. The proposed model may assist in better designing and assessing orthotic therapy for pain relief in patients suffering painful cavus foot deformity.

Trial registration: Randomized controlled trial: ISRCTN84913516.

No MeSH data available.


Related in: MedlinePlus

Plantar pressure magnitude during walking for a typical pes cavus participant not wearing Custom-Made Orthoses, CFO (Figure 2A) and wearing Custom-Made Orthoses (Figure 2B) as well as a typical healthy participant with normal foot alignment (Figure 2C). In participants with normal foot alignment, there is a greater probability of seeing medium pressure values during stance which make up the central part of the normal distribution
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC3924916&req=5

Figure 2: Plantar pressure magnitude during walking for a typical pes cavus participant not wearing Custom-Made Orthoses, CFO (Figure 2A) and wearing Custom-Made Orthoses (Figure 2B) as well as a typical healthy participant with normal foot alignment (Figure 2C). In participants with normal foot alignment, there is a greater probability of seeing medium pressure values during stance which make up the central part of the normal distribution

Mentions: The estimation of the DPLI has been described in our previous publication [8]. In summary, the time-series of peak pressure profile during each stance phase was scaled to 100 samples using a linear interpolation scheme to moderate the effect of gait velocity (stance duration). Then a Gaussian distribution with the same mean, variance, and maximum probability magnitude as the actual data was fitted for each foot and trial using a linear regression model, producing the DPLI [8]. The normal distribution evaluated the probability of observing low, medium or high pressures at any point during stance. For instance, very low and high pressures were expected but usually occur very rapidly (at heel contact and toe off) and therefore account for only a small percentage of the stance phase. These pressures therefore make up the tail ends of the distribution. There was a greater probability of seeing medium pressures during stance and these intermediate pressures made up the central part of the normal distribution (Figure 2). The theoretical value of DPLI is expected to range from - 1 to + 1 and a value close to +1 (regression coefficient =1) is mathematically interpreted as a better agreement between DPLI and the Gaussian distribution.


Mechanism of orthotic therapy for the painful cavus foot deformity.

Najafi B, Wrobel JS, Burns J - J Foot Ankle Res (2014)

Plantar pressure magnitude during walking for a typical pes cavus participant not wearing Custom-Made Orthoses, CFO (Figure 2A) and wearing Custom-Made Orthoses (Figure 2B) as well as a typical healthy participant with normal foot alignment (Figure 2C). In participants with normal foot alignment, there is a greater probability of seeing medium pressure values during stance which make up the central part of the normal distribution
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3924916&req=5

Figure 2: Plantar pressure magnitude during walking for a typical pes cavus participant not wearing Custom-Made Orthoses, CFO (Figure 2A) and wearing Custom-Made Orthoses (Figure 2B) as well as a typical healthy participant with normal foot alignment (Figure 2C). In participants with normal foot alignment, there is a greater probability of seeing medium pressure values during stance which make up the central part of the normal distribution
Mentions: The estimation of the DPLI has been described in our previous publication [8]. In summary, the time-series of peak pressure profile during each stance phase was scaled to 100 samples using a linear interpolation scheme to moderate the effect of gait velocity (stance duration). Then a Gaussian distribution with the same mean, variance, and maximum probability magnitude as the actual data was fitted for each foot and trial using a linear regression model, producing the DPLI [8]. The normal distribution evaluated the probability of observing low, medium or high pressures at any point during stance. For instance, very low and high pressures were expected but usually occur very rapidly (at heel contact and toe off) and therefore account for only a small percentage of the stance phase. These pressures therefore make up the tail ends of the distribution. There was a greater probability of seeing medium pressures during stance and these intermediate pressures made up the central part of the normal distribution (Figure 2). The theoretical value of DPLI is expected to range from - 1 to + 1 and a value close to +1 (regression coefficient =1) is mathematically interpreted as a better agreement between DPLI and the Gaussian distribution.

Bottom Line: Custom-made foot orthoses (CFO) have been shown to be an effective treatment option, but their specificity is unclear.No relationship between change in pressure magnitude and change in symptoms was found in either group.Our data suggest that a primary function of effective orthotic therapy with CFO is redistribution of abnormal plantar pressures.

View Article: PubMed Central - HTML - PubMed

Affiliation: Interdisciplinary Consortium on Advanced Motion Performance (iCAMP), Southern Arizona Limb Salvage Alliance (SALSA), University of Arizona College of Medicine, Tucson, AZ, USA. najafi.bijan@gmail.com.

ABSTRACT

Background: People who have extremely high arched feet or pes cavus often suffer from substantial foot pain. Custom-made foot orthoses (CFO) have been shown to be an effective treatment option, but their specificity is unclear. It is generally thought that one of the primary functions of CFO is redistributing abnormal plantar pressures. This study sought to identify variables associated with pain relief after CFO intervention.

Methods: Plantar pressure data from a randomized controlled trial of 154 participants with painful pes cavus were retrospectively re-analyzed at baseline and three month post CFO intervention. The participants were randomized to a treatment group given CFO or a control group given sham orthoses.

Results: No relationship between change in pressure magnitude and change in symptoms was found in either group. However, redistribution of plantar pressure, measured with the Dynamic Plantar Loading Index, had a significant effect on pain relief (p = 0.001). Our final model predicted 73% of the variance in pain relief from CFO and consisted of initial pain level, BMI, foot alignment, and changes in both Dynamic Plantar Loading Index and pressure-time integral.

Conclusion: Our data suggest that a primary function of effective orthotic therapy with CFO is redistribution of abnormal plantar pressures. Results of this study add to the growing body of literature providing mechanistic support for CFO providing pain relief in painful foot conditions. The proposed model may assist in better designing and assessing orthotic therapy for pain relief in patients suffering painful cavus foot deformity.

Trial registration: Randomized controlled trial: ISRCTN84913516.

No MeSH data available.


Related in: MedlinePlus