Patellofemoral Ağrı Sendromunda Medial ve Lateral Hamstringlerin Kas Aktivasyonunun ve Aktivasyon Zamanının Dinamik Olarak Değerlendirilmesi ve Fizyoterapinin Etkisi

Abstract

This study has been performed aiming to assess time delay differences between the onsets of medial and lateral hamstrings during gait analysis and to investigate the effect of single session of physiotherapy on this possible time delay. A group of 15 patients (30.46±6.22) diagnosed with Patellofemoral Pain Syndrome (PFPS) and age-matched 15 healthy subjects (28.73±7.43) were recruited in this study. In this study which has been performed in Istanbul University, Department of Orthopedics and Traumatology, Gait Analysis Laboratory, the pain intensity level, posture, patellofemoral joint and surrounding soft tissues, functional activity level were evaluated in the first day of the assessment. Besides, hip abductor, extensor, external rotator, knee flexor and extensor isometric muscle strengths were measured with hand-held dynamometer. In the second day, while subjects were walking at self-selected speed, EMG was recorded with surface electrodes, which were placed on the medial and lateral Hamstrings. For gait analysis, 6 high-speed cameras and 2 force plates were synchronized with the surface EMG electrodes and, spatial-temporal parameters were analysized together with hip-knee-ankle kinematics. EMG signals were pre-amplified, band-pass filtered between 10-450 Hz and sampled at 1000Hz. After all evaluations have been completed for the both groups, single session of physiotherapy composed transverse friction massage to LH (Biceps Femoris) and active stretching to ITB were applied to the patients with PFPS. Immediately after this application, EMG has been recorded again to evaluate the acute effects of physiotherapy on LH. There has not been found any differences in spatial-temporal characteristics of the gait and hip-knee-ankle kinematics between the PFPS and the control groups. The time difference between onsets of the contractions of the LH and MH in PFPS and the control group were found as 0.041±0.06 msec. and 0.012±0.04 msec. respectively, and the difference between them was found statistically non-significant (p=0.327). Females of the PFPS group have shown muscle weakness of hip extensors, abductors, external rotators and knee extensors (p<0.005). There was a delay in onset time of LH after physiotherapy application, however, the difference was found statistically non-significant when compared with before physiotherapy application (p=0.24). non- significant, it has been observed that LH’s contraction was initiated before MH in patients with PFPS. Although it was not statistically significant, onset of LH was delayed with a single physiotherapy session. The results of this study could be discussed better with the results of the further studies.