The OSSIOfiber® Trimmable Fixation Nails are indicated for maintenance of alignment and fixation of bone fractures, osteotomies, arthrodesis and bone grafts in the presence of appropriate additional immobilization (e.g., rigid fixation implants, cast, brace). The hypothesis is that the use of OSSIOfiber® Trimmable Fixation Nails for treating subchondral insufficiency of the knee will result in improvement of patient-reported outcomes and imaging findings. The primary objective of this study is to evaluate the effectiveness of implanting bio-integrative OSSIOfiber® Trimmable Fixation Nails, organized in a bi-cortical rafter formation within the tibia or femur for the management of subchondral insufficiency. This use is not considered off-label because the TFNs are being used in the way they are intended to be used via FDA approval.

Inclusion Criteria:

1. Has had knee pain in study knee lasting at least 3 months
2. Candidate for knee arthroscopy due to meniscal tear, loose body, unstable articular cartilage or mechanical symptoms.

Exclusion Criteria:

1. Current tobacco use or has quit within 3 months of study enrolment.
2. Substance abuse history.
3. Diabetes mellitus, HbA1c>8
4. High surgical risk due to pre-existing conditions.
5. Currently pregnant or has plans to become pregnant prior to surgery.
6. Active infection or history of chronic infection in study knee.
7. Will require concomitant procedures within study knee, including but not limited to ligament reconstruction, tendon repair, meniscus repair, microfracture, osteotomy, or osteochondral transplantation. (Meniscal tears, including chronic, are acceptable if no repair is required)

Those who have subchondral insufficiency of the knee with tibial or femoral overload.