Meniscal tissue has very limited intrinsic properties in terms of repair, given the low mitotic activity of chondrocytes and poor vascularization. Nevertheless, its capacity for regeneration, in vivo and in vitro, can be stimulated by the contribution of growth factors, as has been widely described in the medical and scientific literature. Platelet Enhanced Plasma (PRP) is an autologous biological product (that is, derived from the patient's blood) containing a growth factor concentrate. The contribution of these growth factors stimulates cartilage repair by stimulating neovascularization, collagen synthesis and activation of chondrocytes. Intra-articular injection PRP is an autologous biological product, now used in daily practice for the treatment of early osteoarthritic lesions.

The hypothesis of this work is that the injection of PRP in contact with LMD(Degenerative Meniscal Lesions) will improve the clinical symptomatology of our patients compared to reference treatment (intra-auricular injection of corticosteroids).

Inclusion Criteria:

Men and women aged 20 to 80

• MDD diagnosis objected to MRI (grade II/III)
• Joint pain for more than 3 month
• Absence of bone lesion or moderate knee osteoarthritis stage <2 on the Kellgren Laurence scale (objectified on radiography in schuss) in the 6 months prior to inclusion
• Axial deformity of the lower limbs less than or equal to 5 °
• Signed consent signed by the patient
• Ability to perform procedures as part of the follow-up (walk 50 steps on a flat surface and up / down stairs).
• Be affiliated to a health insurance scheme

Exclusion Criteria:

• Axial deformity> 5 °
• Ligament instability
• Major injuries or surgery of the target knee or lateral contralateral knee in the 12 months preceding the inclusion visit
• Ligament reconstruction in the 12 months prior to the inclusion visit
• Need a cane or assistance to move
• BMI> 35
• Thrombocytopenia <150 G / L
• Thrombocytosis> 450 G / L