Difficulty of recruitment due to COVID-19

The study of this study is to evaluate the age influence on cortical bone strength properties by two methods:HR-pQCT (HighResolution-peripheral quantitativeComputedTomography) and ultrasound. The main objective consists in the evaluation of the age influence on cortical thickness at 1/3 distal radius measured by US.

The study of this study is to evaluate the age influence on cortical bone by two methods: HR-pQCT and ultrasound.

84 patients will be measured. The cohort will be:

• 21 women less than 70
• 21 women more than 70
• 21 men less than 70
• 21 men more than 70 Measurement will be performed at radius and at tibia (ultra-distal and distal). For all the sites one measurement will be performed by HR-pQCT to get reference values of thickness and BMDs. For the distal positions and additional measurement will be performed by an innovative ultrasound device that estimates cortical thickness and porosity.

The participation to the study implies only a participation of one hour from the patient (30min for HR-pQCT measurements, 30 min for US).

The main objectives consist in :

• evaluating the age influence on cortical thickness at 1/3 distal radius measured by US
• evaluating the age influence on cortical thickness at distal tibia measured by US
• comparing porosities values measured by US to vBMD obtained by HR-pQCT
• comparing cortical thickness values measured by HR-pQCT at 1/3 distal radius position to ultra-distal radus position and to the tibia
• comparing vBMD values measured by HRpQCT at 1/3 distal radius position to ultra-distal radius position and to the tibia

Inclusion Criteria:

• being 18 or older
• coming from the rheumatology consultation at Lariboisière Hospital

Exclusion Criteria:

• BMI > 28
• BMI < 15
• cortisone treatment
• recent fracture at non-dominant arm
• wound on measuring zone
• treatment interfering with bone architecture or bone density : oral of transdermic oestrogenes, bisphosphonates (Alendronate, Risedronate, Zoledronate) or Denosumab during the past 6 months-

The cohort will be:

Women and men less than 70 Women and men more than 70