Comparison Of Muscle Activation Levels Between Healthy Individuals And Persons Who Have Undergone Anterior Cruciate Ligament Reconstruction During Different Phases Of Weight-Bearing Exercises

ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
Jennifer Howard, Assistant Professor, PhD (Creator)
Institution
Appalachian State University (ASU )
Web Site: https://library.appstate.edu/

Abstract: STUDY DESIGN: Cross-sectional, controlled laboratory study. BACKGROUND: Quantification of muscular activation during different phases of functional activities is important to understand activation deficits in individuals who have undergone anterior cruciate ligament reconstruction (ACLR). OBJECTIVES: To compare activation levels of the vastus medialis (VM), medial hamstrings (MH), and gluteus medius (GMed) muscles during the different phases of weight- bearing tasks between individuals who had undergone ACLR and healthy controls. METHODS: Surface electromyography was used to measure the activation levels of the VM, MH, and GMed muscles in 16 participants who had undergone ACLR (average time since surgery, 4 years) and 15 healthy participants during the reach and return phases of the Star Excursion Balance Test (SEBT) and the ascending and descending phases of a step-down task (SDT). Repeated- measures analyses of variance were performed to determine whether muscle activation levels differed betweengroups during different phases of the tasks. RESULTS: There were significant group-by-phase interactions for the GMed during both the SEBT and SDT. Gluteus medius activation was lower for the ACLR group during the return phase of the posteromedial direction of the SEBT compared to the control group (P = .03). During the SDT, GMed activation was higher for the ACLR group during the ascending phase than during the descending phase (P<.001), while the control group showed no difference between phases (P = .71). CONCLUSION: Individuals who had undergone ACLR have similar VM and MH activation compared to healthy individuals during different phases of the SDT and SEBT. However, phase differences for GMed activity and decreased GMed activity relative to healthy individuals were observed among ACLR participants.

Additional Information

Publication
Harput GH, Howard JS, Mattacola CG (2016). "Comparison of Muscle Activation Levels Between Healthy Individuals and Persons Who Have Undergone Anterior Cruciate Ligament Reconstruction During Different Phases of Weight- Bearing Exercises." Journal of Orthopaedic & Sports Physical Therapy 46(11): 984-992. DOI: 10.2519/jospt.2016.5896. Publisher version of record available at: https://www.jospt.org/doi/full/10.2519/jospt.2016.5896
Language: English
Date: 2016
Keywords
anterior cruciate ligament, electromyography, gluteus medius, knee joint, Star Excursion Balance Test

Email this document to