Bracing Classifications Inside the ACL Brace Technology Hinge Technology Brace Fitting Guidelines Information delivered in this presentation is backed by clinical studies for DonJoy braces.
Prophylactic bracing can significantly reduce the number of knee ligament injuries in a season. Studies Support Facts: ◦ Football (contact): may decrease MCL sprain risk by 20-30%, RTP time decreases. ◦ Motocross: reduces risk of injury to ACL by 50% ◦ Skiing: Reduce ACL re-injury by 3-times. Reduce the risk of contact/high impact knee ligament injuries Albright JP et al. Medial Collateral Ligament Knee Sprains in College Football: Effectiveness of preventative braces. American Journal of Sports Medicine. 1994 22:1. 12-18 Sanders MS, CatesRA, Baker, MD, Barber-Westin SD, Gladin WM, Levy MS. Knee Injuries and the Use of Prophylactic knee bracing in Off-road Motorcycling: Results of a Large-Scale Epidemiological Study. American Journal of Sports Medicine. 2011; 39: 1395-1400 Sterrett WI, Briggs KK, Farley T, Steadman JR. Effect of Functional Bracing on Knee Injury in Skiers with Anterior Cruciate Ligament Reconstruction: A prospective Cohort Study. 2006; 34:1581-1585
Protect the healing graft Allow protected (limited) motion of injured knees or knees that have been treated operatively (4 Points- of-leverage) ◦ Decrease anterior tibial translation Provide proprioceptive awareness and feedback Training in a brace with Fource Point hinge can translate to greater flexion angle at the knee bilaterally
Provide stability and support during activity ◦ Return to Play with brace for extra support if needed. Provide protection for the repaired ligament Stabilize from anterioposterior forces Mainly, reduces strain on the ACL graft to reduce risk of re-injury. Can a brace prevent tibial rotation?
Preserve the life of a joint with arthritic conditions. 3 point load shifts compressive knee joint forces from the degenerative compartment to the healthy compartment Push Pull – ** Uses rotation
200,000 ACL injury cases per year in U.S. Majority of ACL injuries occur while playing agility sports. 70% of ACL injuries are sustained through non- contact mechanisms Most prevalent in active persons 15-45 years of age. Kim, J. (2009, January 1). Anterior Cruciate Ligament Injury.. Retrieved, from http://orthosurg.ucsf.edu/patient-care/divisions/sports-medicine/conditions/knee/anterior-cruciate- ligament-injury-acl/
Women are 2-8 times more likely to sustain an ACL injury playing sports. The re-injury rate for the ACL reconstructed knee is 5-10% Psychological factors, primarily fear of re-injury influence the ability to return to play Kim, J. (2009, January 1). Anterior Cruciate Ligament Injury.. Retrieved, from http://orthosurg.ucsf.edu/patient-care/divisions/sports-medicine/conditions/knee/anterior- cruciate-ligament-injury-acl/
Passive Brace Frame: ◦ passive braces are used to support the static components of the joint, e.g. ligaments, cartilage, and bone geometry. Passive braces don’t consistently address instabilities, which increases the risk of injury Dynamic Brace Frame: ◦ Dynamic braces utilize unique strapping and hinge configurations to carefully disperse pressure on the joints, ligaments, and bone, throughout the soft tissue and surrounding muscles of the joint
Dynamic bracing system Designed to reduce the strain on the ACL Unique cuff & strapping configuration, providing a net differential posterior force to the tibia preventing anterior movement 1 2 3 4
Point 1 (Anterior Thigh Cuff/Posterior thigh Strap) ◦ Anchors the femur Point 2 (Posterior Calf Cuff/Anterior tibial strap) ◦ Anchors the tibia Point 3 (Posterior Distal Thigh Strap) ◦ Pushes the femur anteriorly Point 4 (Anterior Proximal Tibia Strap) ◦ Applies constant posterior load to prevent anterior tibial translation 1 2 3 4
Polycentric Hinge ◦ Thigh frame and calf frame gears connect through 2 different pivoting points within hinge ◦ Stabilizes the knee while matching natural knee kinematics ◦ Maximizes anterior/posterior and varus/valgus stabilizing forces of the brace
Fource Point Hinge ◦ Patented - designed to keep the knee out of the “at risk” position ◦ Leaf spring mechanism provides five levels of resistance during extension ◦ Applies resistance during knee extension ◦ Resistance engages in last 25 0 of extension
How does the Fource Point hinge perform clinically? Immediate Effects of a Knee Brace With a Constraint to Knee Extension on Knee Kinematics and Ground Reaction Forces in a Stop-Jump Task Bing Yu, *† PhD, Daniel Herman, † MS, William Lu, ‡ PhD, Donald T. Kirkendall, † PhD, and William E. Garrett, † MD, PhD From the † University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, and the ‡ University of Hong Kong, Hong Kong Hypothesis: 1) Training in FP hinge for 4 weeks will result in increase knee flexion angle and decreased ground reaction forces during stop jump and side cutting tasks 2) the effects of the training will be retained for up to 4 weeks. 24 recreational athletes, Group A (1 st 4 weeks = no brace, 2 nd 4 weeks = brace) Group B (1 st 4 weeks = brace, 2 nd 4 weeks = no brace) Average increase of 5° in Knee Flexion Angle at Landing Training with FourcePoint (hinge) resulted in increased flexion angles and decreased peak impact ground-reaction forces during stop-jump and side-cutting tasks after 4 weeks Training effects were retained up to 4 weeks (Group B) Conclusion:FourcePoint (hinge) is a useful training tool for the prevention of ACL injuries
Does 5 ° flexion angle increase matter? - The anterior shear force applied on the tibia will be reduced by 9% for females & 13% for males (Nunley et al., 2003) - The decrease in anterior shear force on the tibia will substantially reduce the load on the ACL