Calcaneal bone mineral density in patients with Charcot neuropathic osteoarthropathy: differences between Type 1 and Type 2 diabetes.
OBJECTIVE
To measure bone density and neuropathy in both feet in Type 1 and Type 2 patients with unilateral Charcot osteoarthropathy and controls.


METHODS
Calcaneal bone density, temperature and vibration thresholds were compared between 17 Type 1 diabetic patients with osteoarthropathy and 47 Type 1 controls and between 18 Type 2 diabetic patients and 48 Type 2 controls. As well as the Charcot foot, the non-Charcot foot was studied to assess osteopenia at onset of osteoarthropathy.


RESULTS
In Type 1 diabetes, bone density was reduced in the non-Charcot foot compared with controls [Z-score: -1.7 ({-1.9}-{-1.4}) vs. -0.2 ({-1.1}-{0.5}), P < 0.0001, median (interquartile range)]; but not in Type 2 diabetes [Z-score: 0.15 ({-0.45}-{0.85}) vs. 0.3 ({-0.5}-{0.9}), P = 0.675]. Bone density in the Charcot foot was lower compared with the non-Charcot foot in both Type 1 [Z-score: -2.0 ({-2.8}-{-1.4}) vs. -1.7 ({-1.9}-{-1.4}), P = 0.018] and Type 2 diabetes [Z-score: -0.2 ({-1.4}-{0.1}) vs. 0.3 ({-0.5}-{0.9}), P = 0.001]. In Type 1 diabetes, bone density of the non-Charcot foot was reduced compared with that in Type 2 (P < 0.0001). Body mass index was lower in Type 1 than in Type 2 Charcot patients (P = 0.007). Type 2 patients had high temperature (P = 0.001) and vibration thresholds (P < 0.0001) in the non-Charcot foot compared with Type 2 controls whereas Type 1 patients had a high temperature threshold (P = 0.01) but not vibration threshold compared with Type 1 controls (P = 0.077).


CONCLUSIONS
Bone density was reduced in the non-Charcot foot in Type 1 but not in Type 2 diabetes. Type 2 patients had high temperature and vibration thresholds in contrast to Type 1 patients who had a high temperature threshold only.
Petrova
N L
NL
Diabetic Foot Clinic, King's College Hospital, London, UK. petrovanl@yahoo.com
Foster
A V M
AV
Edmonds
M E
ME
D000328:Adult; D001177:Arthropathy, Neurogenic / Q000503:physiopathology*; D015519:Bone Density / Q000502:physiology*; D002111:Calcaneus / Q000503:physiopathology*; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000150:complications / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged