The study consists of 3 phases (Identification of includable patients, Telephone follow-up evaluation and the collection of study-specific clinical data in medical records of enrolled patients):

• Identification by trained medical personnel of subjects who meet the study's inclusion criteria.
• Once the patient's Informed Consent has been obtained, the study-specific questionnaires will be submitted by telephone.
• Study-specific clinical score data will be collected from the medical records of patients enrolled in the study. These data will be used, together with the data collected during the telephone follow-up, to evaluate the trend in outcomes over time after implantation of this scaffold.

Inclusion Criteria:

• Acute irreparable meniscal injuries requiring partial meniscectomy or chronic meniscal tissue loss (traumatic or degenerative) greater than 25%; Intact anterior and posterior meniscal horn respectively;
• Peripheral meniscal rim (1 mm or more) along the entire circumference of the involved meniscus;
• Knee stability or anterior cruciate ligament injury stabilized at the time of surgery;
• Male or female patients between the ages of 18 and 65 years;
• Healthy contralateral knee;
• Normal axial alignment of the knee (mechanical tibio-femoral angle < 3°)
• Patients treated surgically with scaffolds (Actifit) for partial meniscal defects from January 01, 2009 to December 31, 2019

Exclusion Criteria:

• Patients no longer available;
• Concomitant posterior cruciate ligament (PCL) injury;
• Advanced cartilage injuries according to Outerbridge classification (IV);
• Incorrect axial alignment of the lower limb;
• Documented allergy to polyurethane;
• Local or systemic infection;
• History of previous anaphylactoid reaction;
• Systemic administration of corticosteroids or immunosuppressive drugs within 30 days prior to surgery;
• Evidence of osteonecrosis in the involved knee;
• Positive history of rheumatoid arthritis, inflammatory arthritis and autoimmune diseases;
• Neurological disorders or conditions that may affect the rehabilitation protocol;
• Pregnancy.

Patients will be recruited from all subjects treated surgically with scaffolds (Actifit) for partial meniscal defects from January 01, 2009 to December 31, 2019