Design Evaluation of a Novel Multicompartment Unloader Knee Brace

Area of Science:

• Biomechanical Engineering
• Orthotics and Prosthetics
• Osteoarthritis Management

Background:

• Knee osteoarthritis (OA) significantly impacts the aging population, causing pain and reduced mobility.
• Current conservative treatments like weight loss and unicompartment braces have limitations for many OA patients.
• Existing braces often target only specific knee compartments, leaving multicompartmental OA inadequately addressed.

Purpose of the Study:

• To design and evaluate a novel spring-loaded tricompartment unloader (TCU) knee brace.
• To compare the unloading capacity of the TCU brace with a commercially available knee-extension-assist (KEA) brace.
• To assess the potential of powerful spring-loaded braces for multicompartmental knee unloading.

Main Methods:

• Design and fabrication of a spring-loaded TCU knee brace.
• Measurement and comparison of the force output (assistive moment) of the TCU and KEA braces.
• Calculation of the static unloading capacity provided by each brace during weight-bearing.

Main Results:

• The TCU brace generated a maximum assistive moment equivalent to unloading approximately 45 lbs of body weight.
• The KEA brace provided a maximum assistive moment equivalent to unloading approximately 6 lbs of body weight.
• The TCU brace demonstrated significantly greater unloading capacity compared to the KEA brace.

Conclusions:

• Sufficiently powerful spring-loaded knee braces, like the TCU, show promise as a new class of orthoses.
• These multicompartment unloader braces can provide a clinically meaningful unloading effect across all three knee compartments.
• This technology may offer a viable conservative treatment option for a broader range of knee osteoarthritis patients.