The pre- and post-operative functional assessment of patients' knees is of great interest for the practitioner, whether it is in his or her daily practice to determine the appropriate management of the patient, or to conduct clinical studies. The scores used are established in several languages to provide a uniformly accepted unit of measurement.

The pre- and post-operative functional assessment of patients' knees is of great interest for the practitioner, whether it is in his or her daily practice to determine the appropriate management of the patient, or to conduct clinical studies. The scores used are established in several languages to provide a uniformly accepted unit of measurement.

A large number of functional knee scores already exist. These include scores for Lysholm-Tegner, International Knee Documentation Committee (IKDC) and Knee injury and Osteoarthritis Outcome Score (KOOS), but these can be difficult to apply in practice. daily due to their length, which may be too time-consuming for the clinician when consultations for example.

Shoulder surgeons are familiar with the Simple Shoulder Value (SSV) score, which simply consists of asking the patient how much they value their shoulder on the day of the exam, compared to a normal shoulder in percentage terms. It has been shown to produce results that are close to Constant score or Rowe and American Shoulder Score and Elbow score Surgeons Score after shoulder surgery. It is, since its description, very much used in daily practice by shoulder surgeons because of its speed and simplicity of execution.

No such assessment exists to our knowledge for the knee. The validation of a score of this type for the knee joint would allow the use of a new practical tool for a better patient management while saving the practitioner and the patient money. time in consultation.

The investigators would like to propose a functional knee score similar to the ISS for the shoulder that would allow a self-assessment of the condition of a knee, compared to a normal knee in percentage terms.

The hypothesis is that the SKV (Simple Knee Value) is a valid score giving results of equivalent to the various scores already used in the functional assessment of the knee in the different pathological situations in adult and paediatric populations

Inclusion Criteria:

For the patients:

1. Patients aged 16 to 40 years with ligament rupture anterior cruciate ACL, meniscal lesion, instability or anterior patella dislocation ("young" adult group),
2. Patients over 55 years of age with gonarthrosis. ("Senior" adults group).

For the controls:

In order to test the discriminating qualities of the SKV score, a group young" (16 to 40 years old) and "senior" (16 to 40 years old) adult witnesses, and 55 years old) with no problems with one of their knees.

For all participants :

• Understanding French
• Having given its non-opposition and for minors having obtained the non-opposition of one of the holders of parental authority
• Affiliation to a social security scheme

Exclusion Criteria:

For all participants :

• Memory disorders,
• Psychiatric disorders,
• Patient refusal to participate in the study,
• Patient under the protection of adults (guardianship, guardianship, safeguarding of justice),
• Pregnant and/or breastfeeding woman

Patients aged 16 to 40 years with ligament rupture anterior cruciate ACL, meniscal lesion, instability or anterior patella dislocation ("young" adult group), and patients over 55 years of age with gonarthrosis. ("Senior" adults group).