Prospective evaluation of the safety and effectiveness of the MISHA Knee System.

The study will collect data on the procedural and long-term adverse events, WOMAC pain and function scores, KSS satisfaction, subsequent surgical interventions, BMI levels, range of motion, UCLA activity level of the subjects, and perform radiographic/x-ray evaluations at clinical visits through 5 years post-procedure.

The primary analysis of this study is freedom from device- and procedure-related SSIs at five (5) years post-implantation.

This study will also assess device performance in subjects with intact and retained devices and subjects with devices removed prior to study termination and freedom from conversion to arthroplasty through 5 years.

Study subjects will be followed over a five-year post-implant period.

Key Inclusion Criteria:

1. Subjects aged 25 to 65 years at time of index procedure
2. Body Mass Index (BMI) of < 35
3. Activity exacerbated knee pain isolated to the medial compartment and not global in nature
4. WOMAC pain ≥ 40
5. Failed non-operative OA treatment

Key Exclusion Criteria:

1. Large medial osteophyte(s) or considerable extruded meniscus that may interfere with the placement or function of the device
2. Poor bone quality (e.g., bony erosion, osteopenia, osteoporosis)
3. Ligamentous instability
4. Active or recent knee infection
5. Inflammatory joint disease, including sequalae of viral infections
6. Suspected or documented allergy or hypersensitivity to cobalt, chromium, nickel or other metals
7. History of keloid, hypertrophic or contracture scaring
8. Propensity for restrictive scar formation or adhesions with prior procedures