Ballert Orthopedic :: Newsletters and Articles
The use of a knee orthosis for the purpose of external stabilization of the knee during physical activity is a common practice among orthopedic surgeons and other medical personnel. A knee orthosis is typically prescribed during the post-operative rehabilitation period. But orthotic management utilizing a functional knee orthosis for support and stabilization is also useful for patients who prefer a non-operative approach to anterior cruciate ligament (ACL) insufficiency.
One of the functions of the ACL is to control the anterior translation of the tibia, as well as rotation during knee flexion (bending) and knee extension (straightening). In response to the high incidence of knee injuries owing to the growth of amateur athletics among an aging population, there as been an increase in the number of available knee orthoses designed to address multiplanar and rotary instabilities. Over the past 15 years I have treated hundreds of patients in need of mechanical stabilization for their knees, and have made many different orthotic recommendations to address them. I have also worked with a number of orthopedic surgeons to formulate the best orthotic solutions to meet specific patient needs.
Of the orthoses prescribed for my patients, there are five that I consider the most popular. This article examines how these five orthoses compare with respect to suspension design, weight, comfort, stability and the ability to stop and limit knee motion while permitting maximum knee function. The subjective opinions presented in this article are based on my professional experience with the appliances in a wide variety of clinical circumstances.
Fig. 1. Townsend Premier
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Townsend Premier
The new Townsend Premier knee orthosis has a rigid, ultra-light, low-profile design that provides exceptional control of ACL or MCL insufficiencies. The solid-core graphite shells with lightweight powder coating, the titanium hinges and synergistic suspension strap allow the Townsend to offer a “no migration” guarantee.
In my experience with this new design, I’ve found patient satisfaction to be very high. Patients report that the Premier’s low weight (roughly 16 ounces) and lower profile provide excellent fit and comfort. The premier is recommended for contact sports and activities of daily living.
Unlike many other braces on the market, the Townsend Premier is fabricated from a hand modified cast impression of the leg, a process overseen by certified orthotists. In my experience, this fabrication process ensures the best fit.
The many improvements made by Townsend to the Premier’s design and suspension have made it my most recommended knee orthosis. As a certified orthotist/prosthetist and also an athlete who has had an anterior cruciate reconstruction, I give the Townsend Premier my highest recommendation. Rated “Most Effective.” (Fig. 1.)
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Fig. 2. The DonJoy Defiance
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DonJoy Defiance
The DonJoy Defiance employs their patented four-point leverage design. The orthosis uses four points of counterforce to maintain stability of the tibia and femur, thus preventing anterior drawer of the tibia.
The Defiance has some distinct advantages: it continues to be a leader in weight-to-strength ratio, weighing just 18 ounces. DonJoy uses state-of-the-art laminated carbon fiber construction. Fabrication of this orthosis maximizes the weight, which aids in suspension. The supracondylur pad located on the medial knee joint also adds another suspensory option to maintain orthosis location. The low profile strapping systems, medial and lateral condyle pads and geared polycentric knee
joints provide ideal stability to patients needing AP and MI control.
Apart from these advantages, however, I prefer Townsend’s titanium hinges to the aluminum of the Defiance. Additionally, whereas the Townsend is hand modified from a cast impression of the leg, the DonJoy Defiance is based on measurements (or an unmodified cast if you send it). Rated “Effective.” (Fig. 2)
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Fig. 3. Lenox Hill V.3
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Lenox Hill V.3
The name Lenox Hill is almost synonymous with knee orthosis. Initially developed at Lenox Hill Hospital for Joe Namath in the 1960s, it was the gold standard of knee orthoses for many years. Because it has not changed significantly over the past 30 years, however, it fell out of favor as the popularity of carbon fiber systems grew. Seattle Systems, which recently acquired the LH1, has revamped its design and materials. The new system is now called V.3, and its new carbon fiber frame and low profile strapping system now make it a strong alternative once again. Although I haven’t had much clinical experience with this system, the new V.3 appears to be headed in the right direction with regard to orthotic design. Rated “Effective.” (Fig. 3.)
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Fig. 4. CTi-2 by Innovation Sports
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CTi2
The CTi2 knee orthosis is the newest design from Innovation Sports. Its design is based on the same fundamental bracing theory as the original CTi, namely, the use of a rigid frame and non-elastic straps to control knee motion. New design features of the CTi2 include the Accutrac Knee joints, designed to follow a natural multicentric movement of the knee. Their philosophy was that their knee joint will track the anatomical knee throughout its range of motion, thus ensuring superior bone control. The rigid composite frame provides excellent medial and lateral knee control as well as AP control. The CTi2’s design, ease of fit and excellent stability allow patients to resume activity with comfort, style and support. Rated “Highly Effective.” (Fig. 4.)
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Fig. 5. The OMNI X-Cell System
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The Omni Systems
The Omni Systems of knee control have evolved over the last decade to include the use of lightweight composites, unique molded strap ends for easier patient use, kinematically designed knee joints that move in harmony with the anatomy of the knee, and new liner interface materials. The Omni X-Cell System of thigh restraint was developed to counter the tendency of knee orthoses to migrate during activity. Omni’s new Icon Knee System incorporates either the rigid proximal cuff or the traditional flexible cuff. Omni’s design has fallen out of favor in recent years because they tend to bulk at the knee joints. Though still an effective knee orthosis for controlling and influencing ACL deficient knees, other orthoses with smaller profiles are available. Overall, my rating for these systems is “Effective.” (Fig. 5.)
No knee orthosis can accommodate the needs of every patient. It is imperative that patient, physician and orthotist communicate effectively so that the most appropriate orthotic appliance can be provided.
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