Knee, rearfoot and ankle angles during landing in forward, lateral and backward drop jumps

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and M-L directions) were subtracted from those at pre-test. Student’s t-test was used to compare differences in pre- and post-test postural stability values between the biofeedback and control groups, with the level of statistical significance set at p < 0.05. Results: Pre- and post-test measurements of postural stability using a force plate showed significantly improved stability of bipedal posture in the vibro-tactile biofeedback group compared with the control group. This beneficial effect was observed for the 95% elliptical area and the mean sway distance in the M-L direction. Conclusion(s): The present study showed that balance training with the vibro-tactile biofeedback system, providing supplementary vibratory sensory cues related to center of foot pressure displacement, has immediate beneficial effects on the improvement of postural stability in stroke patients. This conclusion supports the potential of the tactile biofeedback system when performing balancing exercises. Because a small sample of participants was tested in the present study, a larger sample or randomized control trial testing long-term effects should be conducted to validate our results. Implications: Using a tactile-based biofeedback system for balance training in stroke patients may become a potential candidate for improving balance control, and it could also be a suitable system used to avoid visual dependency. Keywords: Vibro-tactile biofeedback system; Postural control; Stroke Funding acknowledgements: This study was supported by the Japan Society for the Promotion of Science under the Founding Program for NEXT Program Ethics approval: Waseda University and Tokyo General Hospital’s Ethics Committee for Human Research approved the procedures employed in the study. http://dx.doi.org/10.1016/j.physio.2015.03.094

Research Report Poster Presentation Number: RR-PO-06-12-Mon Monday 4 May 2015 13:00 Exhibit halls 401–403 KNEE, REARFOOT AND ANKLE ANGLES DURING LANDING IN FORWARD, LATERAL AND BACKWARD DROP JUMPS M. Yasuda 1 , K. Okada 1 , M. Wakasa 1 , A. Saito 1 , Y. Takahasi 2 , K. Shibata 3 , H. Sato 4 , W. Horioka 5 , I. Saito 6 1 Akita

University Graduate School of Health Sciences, Department of Physical Therapy, Akita, Japan; 2 Akita University Hospital, Department of Rehabilitation Medicine, Akita, Japan; 3 Akita City Hospital, Department of Rehabilitation, Akita, Japan; 4 Akita Kousei Medical Center, Department of Rehabilitation, Akita, Japan; 5 Akita Prefectural Center on Development and Disability, Department of Rehabilitation, Akita, Japan; 6 Ugo Municipal Hospital, Department of Rehabilitation, Ugo, Japan Background: Knee angles in single limb landing are important factors associated with noncontact anterior cruciate ligament (ACL) injuries. Although many studies have investigated knee positions in the forward drop jump, noncontact ACL injuries frequently occur during landings in backward or lateral jumps. Furthermore, rearfoot and ankle landing angles have not been well reported. Purpose: To compare knee, rearfoot, and ankle landing angles between the forward, lateral, and backward drop jumps. Methods: Nineteen women without any history of musculoskeletal injury (age, 23 ± 2.0 years; height, 161 ± 7.5 cm; body weight, 51 ± 5.1 kg) were enrolled in the present study. None of the participants had any pain or deformity of knees or feet of both the right and left sides. All the participants performed forward, lateral, and backward drop jumps with their dominant side limb from a 30-cm-high platform, keeping their foot in a neutral position through the procedure. Coronal and sagittal knee angles were recorded by using two high-speed video cameras (EX-ZR1100, CASIO, Japan). To measure the angles, 11 markers (Mocaphm-8, 3M, Japan) were fixed on the sternal manubrium, lateral femoral condyle, lateral malleolus, medial malleolus, and the center of the patella, as well as the acromions, anterosuperior iliac spines, and greater trochanter on both the right and left sides. Image data were analyzed using the digital measurement software (Dartfish version 2.0, Dartfish, Japan). The rearfoot supination and ankle dorsiflexion angles were measured using an electronic goniometer (Biometrics, SG110, Japan) fixed on the posterior side of the lateral malleolus. These data were analyzed at every 10 ms until 100 ms after toe contact. Results: Knee flexion, foot supination, and ankle dorsiflexion angles from 40 to 100 ms after toe contact were

WCPT Congress 2015 / Physiotherapy 2015; Volume 101, Supplement 1 eS1643–eS1721

significantly higher in the forward jump than in the lateral and backward jumps, and were significantly higher in the lateral jump than in the backward jump. In particular, in the knee flexion angle at 90 ms (51.2◦ ± 4.6◦ vs. 43.3◦ ± 6.1◦ and 38.0◦ ± 5.5◦ , respectively; both p = 0.03), the rearfoot supination angle at 70 ms (6.0◦ ± 3.9◦ vs. −3.8◦ ± 5.0◦ and −7.9◦ ± 5.4◦ , respectively; both p < 0.01), and the ankle dorsiflexion angle at 100 ms (23.0◦ ± 5.8◦ vs. 16.6◦ ± 3.0◦ and 13.2◦ ± 5.7◦ , respectively; p < 0.01 and p = 0.03, respectively), differences between the 3 types of jumps were prominent. Coronal observation did not show any significant difference in knee valgus angle between the jump types. Conclusion(s): Compared with those in the forward drop jump, knee flexion, rearfoot supination, and ankle dorsiflexion angles were significantly smaller in the lateral and backward drop jumps, although the valgus angles did not differ between the 3 types of drop jumps. In particular, low flexed positioning of the knee may increase the forward shear force of the tibia, resulting in the high risk of noncontact ACL injury. Implications: To prevent noncontact ACL injuries in sports, careful attention should be given to lateral and backward drop jumps. Keywords: Single limb drop jump; Anterior cruciate ligament injuries; Angle of motion Funding acknowledgements: No funding. Ethics approval: Ethical approval obtained from Akita University Graduate School of Health Sciences Ethics Committee. http://dx.doi.org/10.1016/j.physio.2015.03.095 Research Report Platform Presentation Number: RR-PL-1083 Monday 4 May 2015 13:56 Room 303–304 KINESIO TAPE DID NOT PROMOTE VERTICAL JUMPING PERFORMANCE: A DECEPTIVE CONTROLLED TRIAL Q. Yau 1 , K. Wong 2 , P. Lau 2 , A. So 2 , N. Chan 2 , C. Kwok 2 , K. Poon 2 , R. Cheung 2 1 The

Chinese University of Hong Kong, Orthopaedic & Traumatology, Hong Kong, Hong Kong; 2 Hong Kong Polytechnic University, Rehabilitation Sciences, Hong Kong, Hong Kong Background: Kinesio tape (KT) is one of the most common adhesive therapeutic tapes for injury prevention, rehabilitation, and performance enhancement. It has been suggested that the facilitatory effects of KT may be due to the interplay between cutaneous afferent stimulation and motor unit firing in both central and peripheral nervous systems. A recent deceptive controlled trial reported similar isokinetic

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performance between taped, sham, and tapeless conditions, which indicated that previously reported muscle facilitatory effects may be attributed to placebo effects. However, it has been well documented that isokinetic strength does not strongly correlate with functional performance. Unchanged isokinetic parameters do not necessarily indicate the absence of facilitatory effect in the functional performance. In addition, the previous deceptive study only recruited physically inactive subjects and the effects of KT on athletes remains unknown. Purpose: This study examined the vertical jump performance, in terms of maximum jump height and peak jump power, with and without KT application in volleyball players who were ignorant about KT. Methods: 24 healthy volleyball players (experience ≥1 year) who were ignorant about KT performed maximal countermovement jump under three taping conditions: true facilitatory KT, sham KT, and no KT. Under the pretense of applying adhesive muscle sensors, KT was applied to their quadriceps and gastrocnemius in the first two conditions. Maximal jump height and jump power were measured and analyzed using one-way repeated measures ANOVA. Results: All enlisted participants were confirmed to be ignorant about KT and successfully deceived during the experiment. There was no statistically significant difference in maximal jump height (p = 0.241) and peak jump power (p = 0.158) between three taping conditions. Conclusion(s): These results demonstrated that, after elimination of placebo effects, KT did not facilitate jumping performance, in terms of generating higher jump height yielding greater peak power. These findings indicated that previously reported performance enhancement effects of KT may be resulted from placebo effects only. Implications: Our findings did not support the application of KT for jumping performance enhancement. Keywords: Performance; Placebo; Athlete Funding acknowledgements: The authors are indebted to the participants and volleyball team coaches involved in this study Ethics approval: Departmental Research Committee, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University reviewed and approved the experiment. http://dx.doi.org/10.1016/j.physio.2015.03.096