The purpose of this post-market clinical study is to collect long-term outcomes for DeNovo NT Graft treatment of articular cartilage lesions in the ankle in a standard clinical setting. Outcomes to be assessed include pain, function, activity levels and healthcare resource use.

Articular cartilage lesions in the ankle can cause significant pain and loss of function for young to middle age adults. There are several treatment options for symptomatic articular cartilage injuries depending on a patient's age, symptoms and duration of complaints in addition to the size and condition of the lesion. DeNovo NT Natural Tissue Graft is comprised of fresh particulated juvenile cartilage pieces that are secured inside articular cartilage lesions using fibrin adhesive. DeNovo NT Graft was developed due to the current need for expanded treatment options for the treatment of cartilage lesions, especially large lesions.

This post-market, multicenter, longitudinal data collection study was established to collect clinical outcomes of subjects implanted with DeNovo NT Graft. Data may be obtained either retrospectively or prospectively from patients implanted or to be implanted with DeNovo NT Graft for the treatment of lesion in the ankle. Data to be collected include details of the operative procedure as well as subject pain, function, activity levels, and healthcare resource use through a five year post-operative follow-up period.

Potential subjects are screened for study entry based on a preliminary review of the inclusion and exclusion criteria as it applies to their pre-operative status (unless otherwise noted).

Inclusion Criteria:

• Has an articular cartilage lesion(s) in the ankle for which arthroscopic or surgical intervention with DeNovo NT Graft is warranted or has had prior treatment with DeNovo NT Graft for an articular cartilage lesion(s) in the ankle
• Has voluntarily signed the IRB approved informed consent
• Is of stable health and is able to undergo surgery
• Is male or female over the age of 18 at the time of consent
• Is physically and mentally willing and able to comply with post-operative rehabilitation and routinely scheduled clinical visits.

Exclusion Criteria:

• Displays a high surgical risk as determined by the investigative surgeon
• Is pregnant or breast-feeding
• Has a clinically diagnosed autoimmune disease
• Has an active joint infection or history of chronic joint infection at the surgical site
• Has medical history that would likely make the subject unreliable for the study, or any combination of variables in the investigator's judgment that should exclude a potential subject

Subjects who have received or who are scheduled to receive a DeNovo NT graft for repair of a cartilage lesion in the ankle.