Clinical Evaluation of the Levitation Knee Brace

Osteoarthritis (OA) is a debilitating musculoskeletal disease affecting approximately 1/3 of Canadians over age 25. The disease is characterized by loss of cartilage in the afflicted joint and can be a major source of pain, disability, and reduced quality of life. The direct cost of OA in Canada was $2.9 billion CAD in 2010 and is expected to rise to $7.6 billion CAD by 2031. Total knee replacement (TKR) is often used to restore mobility, and the risk for expensive and invasive revision surgery is 2-5 times higher in OA patients younger than 65 years. Thus, finding an alternate early treatment intervention is imperative for societal and economic health. It is well established that excess joint loading is associated with symptoms of knee pain. Existing knee OA (KOA) braces are designed to unload part of the joint to help reduce symptoms of pain and enable patients to participate in physical activity. However, because the majority of KOA braces are designed to offload only one tibiofemoral compartment, they are not indicated for most patients who suffer from patellofemoral (PF) or multi-compartment KOA. The Levitation "Tri-Compartment Offloader" (TCO) knee brace developed by Spring Loaded Technology (SLT) was designed to reduce KOA pain by decreasing compressive forces in all three compartments of the knee with a silicone "liquid spring" providing knee extension assist. The design is predicted to lower the tensile forces of the quadriceps pulling on the knee, thereby decreasing internal joint forces in all three knee compartments. Survey evidence suggests the TCO provides pain relief and improved function to long-term wearers with KOA, especially those with involvement of the PF compartment. However, the generalizability of these benefits to a larger group needs to be investigated through a controlled clinical study involving patients with PF or multi-compartment KOA. The TCO brace provides both a proprioceptive effect as well as a mechanical effect. Soft-shell neoprene knee braces (or 'sleeves') have been shown to reduce pain in KOA patients, believed to be a result of improved proprioception. In order to better isolate and understand the mechanical effect of the extension assist mechanism of the TCO brace on patient outcomes, we require an intervention group with a proprioception intervention only, such as a neoprene sleeve, to remove the potentially confounding effect of proprioception on measured outcomes. Preliminary clinical trial priorities, design and outcome measures have been developed based on clinical outcomes of interest relating to KOA. Participation from key stakeholders including patients, healthcare providers, healthcare administrators and brace manufacturers is critical to ensure research priorities and outcomes are relevant and meaningful. This study represents an opportunity to work directly with patients in the research process, and to evaluate the outcomes of adopting a patient-oriented research approach. Therefore, the focus of this project is to (1) strengthen our preliminary clinical trial plan by refining the priorities, design and desired outcomes, and (2) complete and evaluate a pilot clinical trial based on patient and knowledge-user participation in all phases of the project.

The overall research goal is to conduct a clinical evaluation of the TCO knee brace for treating PF or multi-compartment KOA while incorporating patient participation for optimized study design, implementation and analysis of key outcome measures. This goal will be accomplished across 3 objectives (OB) that coincide with 3 distinct project phases, whereby each project phase is dependent on the outcomes of the previous project phases.

Phase 1 (OB1): Review and improve clinical trial objectives, design and methodology.

Phase 2 (OB2): Perform a pilot trial to evaluate the TCO knee brace in 30 study participants.

Phase 3 (OB3): Interpret study results and create a knowledge translation (KT) plan.

A fourth study objective (OB4) is to evaluate the impact of patient and researcher engagement on the study. This objective will be addressed throughout the duration of the study.

Study Milestones (Specific Aims - SA relating to Objectives).

SA1.1 Recruit patient partners to form the Patient Advisory Committee (PAC).

SA1.2 Plan and conduct a focus group to review clinical trial design and methodology.

SA1.3 Summarize and incorporate patient and researcher feedback into the clinical trial design.

SA2.1 Recruit pilot study participants and assign into an intervention group.

SA2.2 Collect baseline data and 3-month intervention data.

SA2.3 Perform statistical data analysis.

SA3.1 Plan and conduct a focus group to review study results and solicit ideas for dissemination.

SA3.2 Incorporate feedback into interpretation of pilot trial results.

SA3.3 Create and implement knowledge dissemination plan.

SA4.1 Create framework to evaluate patient and researcher engagement.

SA4.2 Implement evaluation tool to evaluate patient and researcher engagement.

SA4.3 Analyze and summarize results of engagement evaluation.

KOA affects over 14 million individuals in North America. In Canada, the economic burden of OA cost the healthcare system approximately $27.5B in 2010. A significant portion of the economic burden is related to indirect costs from loss of employment, tax dollars, and disability compensation. This is largely driven by a lack of appropriate solutions for KOA patients to maintain independence and mobility. The Levitation TCO knee brace represents a promising new technology for reducing pain and maintaining mobility in patients who have, or are developing KOA. Generating scientific evidence on the effectiveness of the TCO brace will allow patients and healthcare providers to make informed decisions regarding their treatment options for KOA. Involving patients directly in the study design, conduct, interpretation and dissemination activities will increase the relevance and utility of results and the overall impact. If proven effective, this solution will allow patients to continue working and living the lifestyle they enjoy for much longer than they would otherwise. Given the high prevalence of KOA, the TCO brace has the potential to significantly improve quality of life for millions of Canadians, while significantly reducing the economic burden of KOA in Canada and beyond.

Inclusion criteria

• Patellofemoral of combined patellofemoral and tibiofemoral knee osteoarthritis
• Kellgren-Lawrence grade ≥ 2 osteoarthritis (moderate-severe) on weight bearing tunnel view x-ray + skyline
• Experience knee pain that worsens (VAS pain score ≥ 4) with activities such as squatting, rising from seated, and going up and down stairs
• Experience less pain (VAS pain score) in the contralateral knee than in the affected knee during weight-bearing activities
• < 7 degrees of varus/valgus knee alignment
• Knee flexion/extension range of motion from 5-100 degrees minimum
• Between the ages of 18-80
• Able to hear and understand study information and instructions in English
• Must be able to be fit with a Levitation knee brace

Exclusion criteria

• History of arthroplasty or high tibial osteotomy in the affected limb
• Surgery (excluding arthroscopy) on either lower limb within last 6 months
• Arthroscopic debridement of the affected knee within last 3 months
• Received corticosteroid injections in last 3 months
• Received hyaluronic acid or platelet-rich plasma (PRP) injections in last 6 months
• History of rheumatoid arthritis
• Symptomatic disease of the hip, ankle, or foot
• History of traumatic onset of knee pain
• A major lower limb injury within the past year requiring physiotherapy or surgery
• Previous fracture of the tibia or femur of the affected limb
• History of diabetic neuropathy or peripheral vascular disease
• Parkinson's or neurodegenerative order that may affect balance / ability to ambulate
• Use of a non-study provided knee brace on the affected limb over the study period
• Known allergy or adverse skin reaction to neoprene
• Open skin wounds present on the leg of the affected side
• Unable to physically or mentally comply with the wearing of a knee brace
• Any contraindications for knee bracing