Decision of investigational team

Study is prospective and multi-center. Study will include 100 to 200 patients across up to 20 sites.The study sites will be located in the United States.The study objective is to evaluate the safety and performance of the ConforMIS iUni® Unicompartmental Knee Resurfacing Device in patients with single compartment osteoarthritis.

The iUni G2 Unicompartmental Resurfacing Device (iUni) is an FDA cleared and CE Marked implant designed for patients with damage isolated to either the medial or lateral tibiofemoral compartment of the knee. The study subjects will be followed for 10 years post implant. The study objective is to evaluate the safety and performance of the ConforMIS iUni® Unicompartmental Knee Resurfacing Device in patients with single compartment osteoarthritis. The iUni is a patient-specific unicompartmental resurfacing device designed from the patient's unique anatomy using proprietary software which interprets data from the patient's CT scan. The patient matched implant design is then coupled with unique patient-matched disposable instrumentation designed using the same CT data and software. The follow-up visit schedule will include visits at 6 weeks, 6 months (optional), 1 year, 2 years, 5 years and 10 years post implant.The remaining follow-up data collected at years 3, 4, 6, 7, 8, and 9 may be collected via phone call/email and does not require a subject visit to the site.The study sites will be located in the United States.

Inclusion Criteria:

1. Clinical condition included in the approved Indications For Use
2. Unicompartmental osteoarthritis of the medial or lateral tibiofemoral compartment
3. Willingness to participate in the clinical study, to give informed consent and to attend all follow-up visits
4. > 18 years of age

Exclusion Criteria:

1. Simultaneous bilateral procedure required
2. BMI > 35
3. Treatment for cancer within the past 5 years, with the exception of skin cancer
4. Poorly controlled diabetes
5. Neuromuscular conditions which prevent patient from participating in study activities
6. Active local or systemic infection
7. Immunocompromised
8. Fibromyalgia or other general body pain related condition
9. Advanced tricompartmental osteoarthritis
10. Symptomatic patellofemoral disease
11. Rheumatoid arthritis or other forms of inflammatory joint disease
12. Loss of bone or musculature, osteoporosis, osteonecrosis, neuromuscular or vascular compromise in the area of the joint to be operated to an extent that the procedure is unjustified
13. Advanced loss of osteochondral structure on the affected femoral condyle
14. Compromised ACL, PCL or collateral ligament
15. Severe (>15º) fixed valgus or varus deformity
16. Extension deficit > 15 º
17. Prior history of failed implant surgery of the joint to be treated
18. Unwilling or unable to comply with study requirements
19. Participation in another clinical study which would confound results

Patients over 18 who have uni-compartmental osteoarthritis to be treated with a unilateral knee resurfacing procedure