CHAPTER 193 Knee Braces
The knee joint is the largest joint in the body, and traumatic, overuse, and degenerative knee injuries are common. Strength, flexibility, and technique modification have traditionally been essential components in the treatment of knee pain. Improved surgical techniques, arthroscopic advances, and smaller incisions have also enhanced therapy for knee disorders over the last few decades. More recently, knee braces have been used in an attempt to prevent or treat several knee conditions.
Despite their popularity, the appropriate indications and true benefits of many knee braces have not been clearly defined or validated by rigorous research. In addition, brace manufacturers market several different knee braces to address conditions that may be nonspecific and diverse. As a result, confusion often exists regarding when and if knee braces should be used for the prevention or treatment of various knee abnormalities. At this point, it can be said that some knee braces may minimize knee injuries, but the efficacy of most braces has not been confirmed by well-controlled studies. In general, most individuals using knee braces express subjective symptomatic improvements that exceed objective findings. Clinicians must assess the costs and potential risks of knee braces when deciding to use them for individuals. Although knee braces appear relatively safe when used appropriately, they should be used only in conjunction with appropriate education, muscular rehabilitation, technique enhancement, and activity modification.
The clinician should identify the appropriate indication for using a knee brace and explain that the brace may or may not be helpful for a given individual. An appropriately sized prefabricated brace is generally sufficient for most individuals. Although custom braces may distribute weight and fit better and be made of materials more worthwhile for high-level athletes or individuals with abnormal limb contours, they are more expensive. If the individual is a minor, consent should be obtained from the parent or guardian. (See the sample patient consent form online at www.expertconsult.com.) The initial fitting and brace application should be scheduled with adequate time allowed for correct sizing and an explanation of recommended brace care and usage. (See the sample patient education form online at www.expertconsult.com.)
Prophylactic knee braces are used to prevent injury to the MCL or LCL during contact sports or to provide stability during recovery after an MCL or LCL sprain (Fig. 193-1). Although the routine use prophylactic knee braces for collateral ligament injury prevention may be controversial, they do have a more well-defined role during MCL or LCL rehabilitation. Prophylactic knee braces are available as custom or off-the-shelf (prefabricated) models (Figs. 193-2 and 193-3). They have either a single lateral hinged support or bilateral supports with polycentric hinges that are connected by fabric and closures. Cost is greater for custom models, which appear to have greater efficacy during both knee flexion and extension. Although high-level athletes may profit from the weight distribution and fit characteristics of a custom brace, a prefabricated brace is sufficient for most individuals. At-risk athletes, such as football linemen, may particularly benefit from wearing well-fitting prophylactic knee braces on both knees during practices and games. However, it should be noted that prophylactic knee brace use may have a negative impact on an athlete’s speed, agility, fatigability, and endurance.
Figure 193-1 Representative prophylactic knee brace. A, Unilateral hinged bar prophylactic knee brace in a neutral position. B, Valgus-applied force causing increased medial collateral ligament (MCL) tension and potential ligament rupture. Use of the brace would hopefully prevent the MCL tear seen here.