BioPoly® RS Partial Resurfacing Patella Registry Study

Inclusion Criteria:

• Age 21 years and older

• Cartilage lesion(s) located in the facets of the patella that have failed priortherapy (conservative or surgical)

• Symptomatic lesions classified as ICRS grade 2, 3, or 4

• Lesion size may not exceed 3.1 cm2 and must be circumscribed by a 15 mm or 20 mmcircle of normal or nearly normal (ICRS Grade 0 or 1) cartilage, with an overalldepth less than 4 mm from the articulating surface

• Subchondral bone quality sufficient to support the implant

• Understanding and willingness to comply with the post-operative rehabilitationinstructions and follow-up visits.

Exclusion Criteria:

• Body mass index (BMI) ≥ 35

• Generalized degenerative or autoimmune arthritis

• Gout

• Uncorrected chronic malalignment of the patella (may be corrected at the same timeas the implantation of the BioPoly device).

• Uncorrected ligamentous instability (may be corrected at the same time as theimplantation of the BioPoly device).

• Kissing lesion on femur

• More than one implant required to accommodate lesion

• Allergy to ultra-high molecular weight polyethylene (UHMWPE), or hyaluronan/hyaluronic acid (HA)

• Use with opposing articulating femoral components

• Any concomitant painful or disabling disease of the spine, hips, or lower limbs thatwould interfere with evaluation of the afflicted knee

• Pregnant, prisoner, vulnerable population, or unable to provide informed consent.