Influence of a lower leg brace on traction force in healthy and ruptured Achilles tendons.
BACKGROUND
we investigated how ruptured Achilles tendons are loaded in a brace. There is an ongoing discussion whether patients should be recommended to bear weight on the injured limb. However, little is known about the effects of bracing on tensional loading of the healing Achilles tendon: it is uncertain if load-bearing actually stresses the Achilles tendon inside a brace.


METHODS
we measured plantar flexion moment inside the brace, in order to estimate tensional loading of the tendon, by use of an insole with pressure transducers.


RESULTS
after wearing the brace for 1 hour, young healthy individuals reduced their maximum flexion moment during gait by half. Patients with Achilles tendon rupture showed no measurable flexion moment during gait with the brace, 4 or 7 weeks after injury. Only when specifically instructed, they could produce a considerable plantar flexion moment. We noted that gait speed with the brace at 4 weeks correlated with a heel-raise functional test at 1 year: the higher the spontaneous gait speed, the less the functional difference between the injured and the uninjured leg (r(2)=0.68; p=0.002).


CONCLUSIONS
the correlation with gait speed suggests that the patients' general physical aptness has an impact on the end result.
Department of Linköping University, Sweden.
Olof Helge
OH
Sandberg
Department of Linköping University, Sweden.
Ida
I
Dånmark
Department of Linköping University, Sweden.
Pernilla
P
Eliasson
Department of Linköping University, Sweden.
Per
P
Aspenberg
Achilles tendon rupture; bracing; flexion moment; immobilization; loading