Treatment of the Medial Meniscus With the NUsurface(R) Meniscus Implant

Inclusion criteria

• Have a degenerative and/or torn meniscus and/or previous meniscectomy as confirmed by diagnostic MRI.
• Have a pain score of 75 or less on the KOOS pain scale, with 100 being normal.
• Be in neutral alignment +/- 5 degrees of the mechanical axis.
• Be between age 35 and 75 at the time of the planned surgery.
• Be able to be fitted anatomically with a size 30 to 90 NUsurface® device.
• Have a normal mental status.
• Be willing and able to attend all follow up visits, complete all study questionnaires, and undergo required X-ray and MRI schedule.
• Be able and willing to understand and sign the informed consent form.

Exclusion criteria

• Have evidence of a Grade IV articular cartilage loss on the medial tibial plateau or femoral condyle that could contact the NUsurface implant
• Have lateral compartment pain with lateral articular cartilage damage greater than Grade II (OB), and/or a lateral meniscus tear(s)
• Have a varus or valgus knee deformity > 5 degrees.
• Have a laxity level of more than II (ICRS), secondary to previous injury of the anterior cruciate ligament (ACL) and/or posterior cruciate ligament (PCL) and/or lateral collateral ligament (LCL) and/or medial collateral ligament (MCL).
• Have patella instability or non-anatomically positioned patella
• Have patellar compartment pain and/or patellar articular cartilage damage greater than Grade II (OB).
• Need a tibial osteotomy at the time of surgery.
• Have an ACL reconstruction performed less than 9 months before implanting the NUsurface® device
• Have any type of previously implanted prosthetic meniscus or ligament or knee implant made of plastic.
• Have a knee flexion contracture > 10 degrees
• Be unable to flex the knee to 90 degrees
• Have a leg length discrepancy causing a noticeable limp.
• Have had a previous major knee condyle surgery
• Present with insufficiency fractures or avascular necrosis of the medial compartment.
• Have an active infection or tumor.
• Have any type of knee joint inflammatory disease including Sjogren's syndrome.
• Have neuropathic knee osteoarthropathy, also known as Charcot joint.
• Have any medical condition that does not allow arthroscopy at the point of entry to the knee.
• Be pregnant or is a female intending to become pregnant during the study period.
• Be mentally incapacitated.
• Be a prisoner.
• Be a patient who has economic incentive not to improve (e.g., workman's compensation patient)
• Be morbidly Obese (BMI > 35).
• Is unwilling or unable to have an X-ray, Fluro, or MRI of the affected knee