The GOAL Trial: Global, Prospective, Multi-Center, Non-randomized, Controlled Non-inferiority Trial to Evaluate Symptom Relief in Patients with Medial Knee Osteoarthritis (OA) Treated with the KineSpring® Knee Implant for Load Reduction Compared to High Tibial Osteotomy (HTO).

Study Objective

The primary objective of this post-market acceptance study is to:

• Demonstrate the non-inferiority of the KineSpring System compared to the standard surgical, high tibial osteotomy procedure in improving pain and function outcomes (as measured by the WOMAC pain and function subscales) at 24 months in patients with primarily uni-compartmental medial knee osteoarthritis.
• Demonstrate that the KineSpring System is safe as measured by procedure and device-related complication rates through 24 months post-operatively The secondary objectives of the pivotal study are:
• To evaluate symptom severity changes from baseline measurement for each of the following outcome measures at each follow-up visit:
• Knee Injury Outcomes Scores (KOOS) including WOMAC Pain, Stiffness and Function Scores
• Knee Society Knee and Function Scores
• Knee range of motion as measured by degrees of flexion and extension
• Pain severity using the knee specific pain severity score (VAS)
• Patient global status
• High Arthroplasty Activity Score (HAAS)
• Generic health status using the EQ-5D  
• To evaluate radiographic changes
• Kellgren Lawrence Grade
• Ahlbäck Grade
• Joint space
• Device functionality

Study Objective

All patients presenting with knee pain secondary to medial knee osteoarthritis and have failed to improve after at least six months of conservative medical treatment may be eligible for study participation. Potential study candidates will be approached for consent prior to any data collection. A screening and enrollment log will be provided to study sites to maintain a record of all screened patients.

Inclusion criteria

1. Male or female subjects ≥25 years of age
2. Documented diagnosis of knee OA with a minimum of 12 months duration
3. Radiographic confirmation of medial compartment knee OA as demonstrated by a Kellgren-Lawrence grade of ≥ 2 (scale 0-4) as assessed by the Investigator
4. Undergone at least six months of conservative treatment prior to surgery
5. Knee flexion range ≥90 - ≤140 degrees
6. WOMAC pain score of at least 40 (scale 0-100) at both the screening and baseline visits
7. BMI < 35 or weight < 300 lbs
8. Candidate for a high tibial osteotomy procedure
9. Subjects who are able to give voluntary, written informed consent to participate in this clinical investigation and from whom consent has been obtained
10. Subjects, who, in the opinion of the Clinical Investigator, are able to understand this clinical investigation, cooperate with the investigational procedures and are willing to return for all the required post-treatment follow-ups.

Exclusion criteria

1. Significant OA in lateral compartment as measured by Kellgren Lawrence grade of ≥2 or significant OA in patellofemoral compartment
2. Significant OA in the contralateral knee likely to necessitate surgical intervention within 12 months of enrollment
3. Tibial-femoral varus or valgus alignment >10 degrees
4. Flexion deformity > 10 degrees
5. Hyperextension >5 degrees
6. Ligamentous instability as assessed by the Investigator on physical examination
7. Active infection, sepsis or osteomyelitis, history of infection in the target knee or distant foci of infections which may spread to the implant site
8. Previous joint modifying surgery in the target knee are excluded within 12 months prior to planned study surgery date, such as ligament reconstruction or meniscus repair, cartilage transplantation, and microfracture. Arthroscopic surgeries for joint lavage, menisectomy, chondral debridement, and    loose body removal are excluded within 3 months prior to planned  tudy surgery date.
9. Previous osteotomy or failed knee joint replacement in the target knee
10. Known sensitivity to metal implants
11. Rheumatoid arthritis, other forms of inflammatory joint disease or autoimmune disorder
12. Paget’s disease or metabolic disorders which may impair bone formation
13. Moderate to severe osteoporosis as evidenced by radiolucency of the femoral or tibial cortex on x-ray
14. Charcot’s joint disease or other severe neurosensory deficits
15. Immunologically suppressed or immunocompromised
16. Currently undergoing long-term steroid therapy (treated in the last 6 months with systemic corticosteroids)
17. Any significant medical condition (e.g., uncontrolled diabetes mellitus, significant psychiatric disorders, active alcohol/drug abuse, etc) or other factor (e.g. planned relocation, uncooperative patient) that the Investigator feels would interfere with study participation.
18. Litigation for or workers compensation for musculoskeletal injuries or disorders
19. Is either pregnant or interested in becoming pregnant during the duration of the study
20. Subjects who are currently enrolled in the treatment phase of another clinical investigation that could affect the results of this trial

Centre Hospitalier de Luxembourg - Clinique d'Eich