RESUMO
PURPOSE: The purpose of this study was to assess the ability of 2 commonly used knee braces to control knee valgus motion and subsequent strain on the medial collateral ligament (MCL) in a laboratory-controlled environment. METHODS: Twenty healthy individuals (6 male, 14 female; mean age, 23 ± 3 years) with no history of knee injury or brace use performed a jump landing task while wearing either no brace or 1 of 2 braces: the Playmaker and Total Range of Motion . Three-dimensional joint kinematics and kinetics were measured in our biomechanics laboratory. RESULTS: Significantly less knee dynamic valgus angulation was noted when using either brace (-0.51° ± 3.9° and -1.3° ± 3.2°) compared no brace (4.8° ± 3.0°). Dynamic valgus angulation did not differ significantly between the 2 braces tested, which were both not statistically different from baseline alignment. There were significant differences seen in peak knee flexion angle between each brace (77.9° ± 8.8°and 83.1° ± 8.4°), as well as between both braces and no brace (90.6° ± 11.1°). There was no significant difference in knee frontal plane moment or peak vertical ground reaction force loading among all 3 testing conditions. CONCLUSIONS: Compared to no brace, both braces allowed significantly less dynamic valgus angulation of the knee under physiological vertical loads but were not significantly different from one another. CLINICAL RELEVANCE: Knee braces are commonly used to protect the MCL when placed under physiological loads. It is important to know which braces effectively reduce valgus stress to provide the best outcomes.
RESUMO
PURPOSE OF THE REVIEW: To review the relevant literature surrounding acromioclavicular (AC) joint injuries particularly pertaining to overhead athletes. RECENT FINDINGS: The AC joint is a unique anatomic and biomechanical portion of the shoulder that can be problematic for athletes, particularly throwers, when injured. Treatment of these injuries remains a topic in evolution. Low-grade injuries (Rockwood types I & II) are typically treated non-operatively while high-grade injuries (types IV, V, and VI) are considered unstable and often require operative intervention. Type III AC separations remain the most controversial and challenging as no clear treatment algorithm has been established. A wide variety of surgical techniques exist. Unfortunately, relatively little literature exists with regard to overhead athletes specifically. Treatment of AC joint injuries remains challenging, at times, particularly for overhead athletes. Operative indications and techniques are still evolving, and more research is needed specifically surrounding overhead athletes.
