Overpronation and achilles strain

NewsBot · Jan 13, 2019

Members do not see these Ads. Sign Up.
Differences in the strain applied to Achilles tendon fibers when the subtalar joint is overpronated: a simulation study
Mutsuaki EdamaTomoya TakabayashiTakuma InaiTakanori KikumotoWataru ItoEmi NakamuraRyo HirabayashiMasahiro IkezuFumiya KanekoIkuo Kageyama
Surgical and Radiologic Anatomy: 08 January 2019

Purpose
The purpose of this study was to investigate the strain applied to each of the tendon fiber bundles of the medial head of the gastrocnemius (MG), the lateral head of the gastrocnemius (LG), and the soleus muscle (Sol) that compose the Achilles tendon (AT) when the subtalar joint is pronated and supinated.

Methods
Three AT twist types (least, moderate, extreme) were investigated. Using the MicroScribe system, the AT and the talocrural and subtalar joints were digitized to reconstruct three-dimensional models. Using this system, subtalar joint rotations in the pronation (20°) and supination (20°) directions were simulated, and the degrees of strain (%) on each tendon were calculated.

Results
For all twist types, when the subtalar joint was pronated, MG, LG, and Sol stretched, and when supinated, MG, LG, and Sol shortened. In particular, the least and severe twist types had large degrees of strain of Sol when the subtalar joint was pronated, and furthermore, each tendon fiber composing Sol had different degrees of strain.

Conclusions
The study results suggest that the degree of strain applied within the AT with subtalar joint pronation is not constant, and that, especially in least and extreme twist types, the risk of developing AT disorders may increase.
Click to expand...

Craig Payne · Jan 13, 2019

"The study results suggest that the degree of strain applied within the AT with subtalar joint pronation is not constant" = subject specific response

Admin2 · Jan 13, 2019

Related Threads:
Influence of calcaneus angle and muscle forces on strain distribution in the human Achilles tendon
Overpronation and achilles tendon blood flow
Effects of foot orthoses on Achilles tendon load
Running shoes and achilles tendon loads
STJ Axis Variations and Achilles Tendonitis

Romanair · Jan 14, 2019

"when the subtalar joint was pronated, MG, LG, and Sol stretched"
Could that in turn mean that a short or inflexible tenton-muscle unit promotes or even exaggerates an excessive rearfoot eversion in for example flexible flatfoot?
Can the results of this study hint towards this hypotheses or does anyone know of any study in this direction?

Simon Spooner · Jan 15, 2019

Romanair said: ↑

"when the subtalar joint was pronated, MG, LG, and Sol stretched"
Could that in turn mean that a short or inflexible tenton-muscle unit promotes or even exaggerates an excessive rearfoot eversion in for example flexible flatfoot?
Can the results of this study hint towards this hypotheses or does anyone know of any study in this direction?
Click to expand...

A short musculo-tendon unit should result in increased internal supination moment acting about the subtalar joint axis, but the reason we see increased pronation in concert with tight/ short tendo Achilles is explained by the equinus paradox.

NewsBot · Apr 4, 2019

The relationship between movement of the shank while running and foot alignment factors that lead to the onset of Achilles peritendinitis.
Kurihara Y et al
J Phys Ther Sci. 2019 Mar;31(3):227-231

[Purpose] To clarify the relationship between movement of the shank relative to the global reference frame (shank angle) while running, and foot alignment factors that lead to the onset of Achilles peritendinitis.
[Participants and Methods] This study included 54 healthy male participants. Running at a constant speed was measured by three-dimensional motion analysis. The shank angle at the time of the first peak of vertical ground reaction force and maximum ankle dorsiflexion were analyzed. The magnitude of ankle plantarflexion, inversion, and adduction angle in the propulsive phase as well as static foot alignment (navicular index, and range of ankle dorsiflexion angle) were measured. The relationships between shank angle features and these parameters were investigated.
[Results] Outward inclination of the shank occurred at the time of the first peak of vertical ground reaction force and maximum ankle dorsiflexion, with this increase in movement correlating with parameters that increased the risk of Achilles peritendinitis.
[Conclusion] These findings suggest that evaluation of the shank angle on the frontal plane while running may be used to estimate the onset of Achilles peritendinitis in clinical practice.
Click to expand...

NewsBot The Admin that posts the news.

Craig Payne Moderator

Admin2 Administrator Staff Member

Romanair Member

Simon Spooner MVP

NewsBot The Admin that posts the news.

Overpronation and achilles tendon blood flow

The intrinsic foot muscles and overpronation

Severe overpronation

puzzling symptoms (overpronation, possible nerve issues)

Free moments and "overpronation"

Flat feet with overpronation :\

Overpronation

Share This Page