Cheuy VA, Hastings MK, Commean PK, Mueller MJ, et al.
Foot & ankle international. Date of publication 2016 May 1;volume 37(5):514-21.
1. Foot Ankle Int. 2016 May;37(5):514-21. doi: 10.1177/1071100715621544. Epub 2015
Dec 14.
Muscle and Joint Factors Associated With Forefoot Deformity in the Diabetic
Neuropathic Foot.
Cheuy VA(1), Hastings MK(2), Commean PK(3), Mueller MJ(2).
Author information:
(1)Physical Therapy Program, University of Colorado, Aurora, CO, USA
victor.cheuy@ucdenver.edu.
(2)Program in Physical Therapy, Washington University School of Medicine, St.
Louis, MO, USA.
(3)Mallinckrodt Institute of Radiology, Washington University School of Medicine,
St. Louis, MO, USA.
BACKGROUND: Diabetic forefoot joint deformities are a known risk factor for skin
breakdown and amputation, but the causes of deformity are not well understood.
The purposes of this study were to determine the effects of intrinsic foot muscle
deterioration and limited ankle joint mobility on the severity of
metatarsophalangeal joint (MTPJ) deformity, and determine the relationships
between these potential contributing factors and indicators of diabetic
complications (peripheral neuropathy and advanced glycation end products).
METHODS: A total of 34 participants with diabetic neuropathy (average age, 59
years; range 41-73) were studied. MTPJ angle and intrinsic foot muscle
deterioration were measured with computed tomography and magnetic resonance
imaging, respectively. Maximum ankle dorsiflexion was measured using kinematics.
Skin intrinsic fluorescence served as a proxy measure for advanced glycation end
product accumulation.
RESULTS: Total forefoot lean muscle volume (r = -0.52, P < .01) and maximum ankle
dorsiflexion (r = -0.42, P < .05) were correlated with severity of MTPJ
deformity. Together they explained 35% of the variance of MTPJ angle. Neuropathy
was correlated with forefoot muscle deterioration (ρ = 0.53, P < .01). Skin
intrinsic fluorescence was correlated to severity of neuropathy (r = 0.50, P <
.01) but not maximum ankle dorsiflexion, or forefoot deterioration when
controlling for neuropathy.
CONCLUSION: These results suggest that the interplay of intrinsic foot muscle
deterioration and limited ankle mobility may be the primary contributor to the
development of MTPJ deformity. Identifying these muscle and ankle motion
impairments as risk factors for MTPJ deformity supports the need for targeted
interventions early in the disease process to slow, or possibly stop the
progression of deformity over time and reduce the risk of amputation.
LEVEL OF EVIDENCE: Level IV, case series.
© The Author(s) 2015.
DOI: 10.1177/1071100715621544
PMCID: PMC5111819
PMID: 26666675 [Indexed for MEDLINE]