Changes in landing mechanics in patients following anterior cruciate ligament reconstruction when wearing an extension constraint knee brace.
Abstract
BACKGROUND: Anterior cruciate ligament (ACL) reconstruction is associated with a high
incidence of second tears (graft tears and contralateral ACL tears). These secondary
tears have been attributed to asymmetrical lower extremity mechanics. Knee bracing
is one potential intervention that can be used during rehabilitation that has the
potential to normalize lower extremity asymmetry; however, little is known about the
effect of bracing on movement asymmetry in patients following ACL reconstruction.
HYPOTHESIS: Wearing a knee brace would increase knee joint flexion and joint symmetry.
It was also expected that the joint mechanics would become more symmetrical in the
braced condition. OBJECTIVE: To examine how knee bracing affects knee joint function
and symmetry over the course of rehabilitation in patients 6 months following ACL
reconstruction. STUDY DESIGN: Controlled laboratory study. LEVEL OF EVIDENCE: Level
3. METHODS: Twenty-three adolescent patients rehabilitating from ACL reconstruction
surgery were recruited for the study. The subjects all underwent a motion analysis
assessment during a stop-jump activity with and without a functional knee brace on
the surgical side that resisted extension for 6 months following the ACL reconstruction
surgery. Statistical analysis utilized a 2 × 2 (limb × brace) analysis of variance
with a significant alpha level of 0.05. RESULTS: Subjects had increased knee flexion
on the surgical side when they were braced. The brace condition increased knee flexion
velocity, decreased the initial knee flexion angle, and increased the ground reaction
force and knee extension moment on both limbs. Side-to-side asymmetry was present
across conditions for the vertical ground reaction force and knee extension moment.
CONCLUSION: Wearing a knee brace appears to increase lower extremity compliance and
promotes normalized loading on the surgical side. CLINICAL RELEVANCE: Knee extension
constraint bracing in postoperative ACL patients may improve symmetry of lower extremity
mechanics, which is potentially beneficial in progressing rehabilitation and reducing
the incidence of second ACL tears.
Type
Journal articlePermalink
https://hdl.handle.net/10161/8891Published Version (Please cite this version)
10.1177/1941738114524910Publication Info
Butler, Robert J; Dai, Boyi; Garrett, William E; & Queen, Robin M (2014). Changes in landing mechanics in patients following anterior cruciate ligament reconstruction
when wearing an extension constraint knee brace. Sports Health, 6(3). pp. 203-209. 10.1177/1941738114524910. Retrieved from https://hdl.handle.net/10161/8891.This is constructed from limited available data and may be imprecise. To cite this
article, please review & use the official citation provided by the journal.
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Show full item recordScholars@Duke
Robert John Butler
Adjunct Associate Professor in the Department of Orthopaedic Surgery
Construction of standards for a functional testing continuum for ACL patients to optimize
durability and performance.Development of field expedient tests to predict musculoskeletal
injury. Predictors of the early presentation of knee osteoarthritis following a joint
injury.
William Elwood Garrett Jr.
Professor of Orthopaedic Surgery
Muscle forces not only provide propulsion to the body, they also provide protection
for the tremendous loads across muscles and joints. Understanding muscle actions joint
interaction is key to improving our ability to prevent injury and scientifically rehabilitate
ligaments and joints. The laboratory employees EMG analysis of muscle function, high
speed motion analysis, force plate, and goniometric data as well as standard exercise
physiologic measurements of strength, aerobic and anaerobic powe
This author no longer has a Scholars@Duke profile, so the information shown here reflects
their Duke status at the time this item was deposited.
Robin Marie Queen
Assistant Professor of Orthopaedic Surgery
This author no longer has a Scholars@Duke profile, so the information shown here reflects
their Duke status at the time this item was deposited.
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