This research explores Knee Joint Distraction (KJD) as a viable, joint-preserving technique for younger patients suffering from advanced tibiofemoral osteoarthritis (OA). The methodology aims to temporarily unload the knee joint, fostering an environment for natural healing and cartilage repair. The ultimate goal is to delay the need for a more definitive surgical solution like Total Knee Arthroplasty (TKA) and reduce the risk of future revision surgeries. This report details the fundamental principles, surgical technique, and clinical outcomes associated with KJD, presenting a powerful alternative for a patient population often considered too young for traditional joint replacement.
The Basic Science of Cartilage Preservation
The fundamental principle behind Knee Joint Distraction is to leverage the body’s natural healing processes to repair damaged cartilage. The technique involves temporarily separating the tibia and femur, which are the bones of the knee joint. This unloading process alleviates the constant “bone-on-bone” pressure and mechanical stress that characterises advanced osteoarthritis. By creating a space between the articular surfaces, the joint is given an opportunity to regenerate and repair itself. This approach is a significant conceptual departure from surgical procedures that involve removing damaged tissue, and it has garnered attention as a “self-repair cartilage procedure” that is particularly exciting for surgeons seeking to offer alternatives to conventional methods. The procedure is typically reserved for patients under 65 years of age with late-stage tibiofemoral OA, but not for those with patellofemoral arthritis behind the kneecap.
Surgical Principles and Technique
The surgical procedure for Knee Joint Distraction is a minimally invasive technique that takes approximately 30-45 minutes after a short learning curve. A key component is the use of an external fixator, such as the KneeReviver, which is secured to the knee using eight bone pins drilled into the femur and tibia. The pins are placed extra-articularly, leaving the joint itself undisturbed. The distraction process begins with an immediate separation of the bones by 2mm, and then the patient gradually increases the distraction by 1mm each day until a total of 5mm is reached, typically within three days of the surgery. This external frame is worn for approximately six weeks. The knee is held in a fixed, straightened position during this period. Post-surgery, patients are encouraged to mobilise early to improve blood flow and reduce the risk of deep vein thrombosis (DVT). A key benefit is that most of the pain experienced is from the pin sites, not the joint distraction itself.
Promising Outcomes and Clinical Efficacy
Clinical outcomes from Knee Joint Distraction have been promising, with some studies demonstrating its potential for cartilage repair and symptom relief. Patients have reported significant improvements in pain scores, with one study showing a 61% decrease in pain after two years. Systematic reviews have found substantial improvements in patient-reported outcomes that persisted for up to nine years, while other research has shown clear benefits in both short-term and long-term structural parameters, with
cartilage regeneration documented up to 10 years after treatment. KJD has been shown to produce clinical results comparable to High Tibial Osteotomy (HTO) and
Total Knee Arthroplasty (TKA), although TKA may still offer a better clinical response in some cases. For many, KJD serves as an effective method for delaying the need for a total knee arthroplasty for at least two years. However, it is important to note that the technique has been associated with a high risk of pin tract infections, which is a key consideration for patients, most of whom will eventually require a total knee replacement.
For a deeper dive into the full findings and methodology, the complete research paper is available here:
Role of joint distraction in osteoarthritis of the knee: Basic science, principles and outcomes
