IMMEDIATE AND PROLONGED EFFECTS OF THERAPEUTIC ELASTIC TAPE ON VASTI MUSCLE ACTIVATION

IMMEDIATE AND PROLONGED EFFECTS OF THERAPEUTIC ELASTIC TAPE ON VASTI MUSCLE ACTIVATION S.E. Risso, K.M. Bishop, M.S. Fogarty, A.L. Johanson, A.D. LaGoy, M.M. O’Hollaren, A.E. Zander, R.S. McCulloch Gonzaga University, Spokane, WA Patellofemoral pain syndrome (PFPS) is a common ailment that can cause severe anterior knee pain. Up to 40% of patients seen in orthopedic clinics for knee pain are diagnosed with PFPS. One proposed mechanism of PFPS is lateral tracking of the patella due to imbalance between the vastus medialis (VM) and vastus lateralis (VL) muscles. A low VM: VL activation ratio has been correlated with increased patellar tilt in subjects with PFPS. Despite increased usage of therapeutic elastic tape for injury prevention and rehabilitation for conditions such as knee pain, its effectiveness has not been extensively studied. PURPOSE: To determine if therapeutic elastic tape has a positive effect on the VM: VL activation ratio in healthy subjects, and thus whether further testing should be done to examine its effects in PFPS patients with patellar maltracking. METHODS: Thirteen healthy, active, female undergraduate students participated in four testing sessions. In sessions one and three, therapeutic elastic tape or placebo tape was applied to the subjects’ VM in a randomized and counterbalanced manner. Muscle activation was then tested during a step activity ten minutes post taping to determine the short term effects of therapeutic elastic tape. To determine long term effects, subjects kept the tape on for 3 days, after which time they returned to the lab for session two or four. During each session, subjects performed a warm up followed by a maximum voluntary contraction (MVC) and step up for which electromyography (EMG) data was recorded for VM and VL. The MVC consisted of three knee extensions against resistance. After a two minute rest, subjects performed three step ups onto a 19.6 cm box. Step rate was standardized using a metronome set at 40 bpm. Average EMG values were converted to a percentage of MVC from which the VM: VL activation ratio was calculated. RESULTS: No significance was found for effect of time (F (1, 9) = 0.15, p = 0.704), taping condition (F (2, 18) = 0.32, p = 0.730), or interaction of time and tape (F (2, 18) = 0.67, p = 0.523). CONCLUSIONS: The current study does not support the clinical use of therapeutic elastic tape for improved VM: VL ratio. Further research is suggested to determine the effects of therapeutic elastic tape in other applications