Long-term Follow-up of Actifit® Meniscal Scaffold Patients.

This study will collect retrospective patient data of Actifit patients (medial and lateral, isolated cases as well as cases with concomitant procedures), including pre-op and any post-op imaging, for 120 retrospective Actifit patients, to account for drop-outs and patients refusing a follow-up visit/follow-up imaging.

Each patient without evidence of previous removal of the scaffold, revision to arthroplasty or joint-modifying surgery at the index knee will be contacted by the site, first by phone, to check whether the Actifit device is still in place or not. If no longer in place, patient's situation will be clearly documented, this will preferentially be done via phone or, if necessary, via a prospective visit. If the Actifit is still in place, a prospective follow-up visit will be organised so that patient's current situation can be documented. The prospective follow-up visit may be via an in-person clinic visit (preferred since the visit, provided the patients agrees, includes imaging), telephone or video conference. Any newly occurring events during this prospective visit will also be documented. Of the 120 retrospective patients, we anticipate a group of about 60-100 study participants with the Actifit still in place and being invited to a prospective follow-up visit.

Consent will be requested to collect specific questionnaires (IKDC, KOOS, VAS-pain and, in case available at baseline, Lysholm) and, in case the study participant also agrees to this, an X-Ray/MRI will be collected, provided any previous imaging is \> 365 days old.