Effect of Biophysical Stimulation on Intraspongious Bone Edema in Anterior Cruciate Ligament Reconstruction

Inclusion Criteria: * patients completely sane and lucid * acute lesion of the acl (date of trauma not exceeding 21 days) * presence of bone bruise diagnosed by magnetic resonance imagine (diagnosed as presence of a hyperintense signal area at the subchondral bone level in the fast spin echo T2 scans with fat saturation or STIR (short tau inversion recovery) Exclusion Criteria: * patients who have undergone previous surgery on the same knee or lower limb * patients with previous cartilage lesions of the affected knee * patients with major axial deviations of the knee (varus or valgus alignment \> 10°) * patients who are taking cortisone therapies, use steroids, abuse alcohol * menopausal women * obesity (BMI\> 30 Kg / m²) * ongoing infections * patients with rheumatoid arthritis, autoimmune diseases, systemic diseases, neoplasms * reduced motility of the knee (active flexion equal or less than 90 ° before surgery) * chronic rupture of the ACL (due to an injury of more than 21 days) * 3rd grade medial collateral ligament rupture * Grade 3 or 4 osteonecrosis according to the International Cartilage Repair Society (ICRS) classification criteria * previous total meniscectomy