Lower leg muscle strengthening does not redistribute plantar load in diabetic polyneuropathy: a randomised controlled trial

This manuscript helps to answer questions many have had for some years in this area.

Journal of Foot and Ankle Research 2013, 6:41 doi:10.1186/1757-1146-6-41
Tom Melai (Tom.Melai@MaastrichtUniversity.nl)
Nicolaas C Schaper (N.Schaper@MUMC.nl)
T Herman IJzerman (T.H.IJzerman@VU.nl)
Ton LH de Lange (ALH.deLange@hetnet.nl)
Paul JB Willems (Paul.Willems@MaastrichtUniversity.nl)
Valéria Lima Passos (Valeria.Limapassos@MaastrichtUniversity.nl)
Aloysius G Lieverse (L.Lieverse@MMC.nl)
Kenneth Meijer (Kenneth.Meijer@MaastrichtUniversity.nl)
Hans HCM Savelberg (Hans.Savelberg@MaastrichtUniversity.nl)

Background
Higher plantar pressures play an important role in the development of plantar foot ulceration
in diabetic polyneuropathy and earlier studies suggest that higher pressures under the forefoot
may be related to a decrease in lower leg muscle strength. Therefore, in this randomised
controlled trial we evaluated whether lower-extremity strength training can reduce plantar
pressures in diabetic polyneuropathy.

Methods
This study was embedded in an unblinded randomised controlled trial. Participants had
diabetes and polyneuropathy and were randomly assigned to the intervention group (n = 48)
receiving strength training during 24 weeks, or the control group (n = 46) receiving no
intervention. Plantar pressures were measured in both groups at 0, 12, 24 and 52 weeks. A
random intercept model was applied to evaluate the effects of the intervention on peak
pressures and pressure–time-integrals, displacement of center-of-pressure and the forefoot to
rearfoot pressure–time-integral-ratio.
Results
Plantar pressure patterns were not affected by the strength training. In both the intervention
and control groups the peak pressure and the pressure–time-integral under the forefoot
increased by 55.7 kPa (95% CI: 14.7, 96.8) and 2.0 kPa.s (95% CI: 0.9, 3.2) over 52 weeks,
respectively. Both groups experienced a high number of drop-outs, mainly due to
deterioration of health status and lower-extremity disabilities.
Conclusions
Plantar pressures under the forefoot increase progressively over time in people with diabetic
polyneuropathy, but in this study were not affected by strength training. Future intervention
studies should take this increase of plantar pressure into account and alternative interventions
should be developed to reduce the progressive lower extremity problems in these patients.
Trial registration
This study was embedded in a clinical trial with trial number NCT00759265.

David G. Armstrong

Dedicated to amputation prevention, wound healing, diabetic foot, biotechnology and the intersection between medical devices and consumer electronics.

Leave a Reply