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Now showing 1 - 6 of 6
  • Publication
    ESMAC 2021 Abstracts
    (Elsevier Ireland Ltd., 2021) AKALAN, NAZİF EKİN; GÖRGÜLÜ, M.; AYDIN, B.; Sert. R.; Bilgili F.
  • PublicationRestricted
    Intraoperative Testing of Passive and Active State Mechanics of Spastic Semitendinosus in Conditions Involving Intermuscular Mechanical Interactions and Gait Relevant Joint Positions
    (Elsevier, 2020) Kaya, Cemre S.; Bilgili, Fuat; AKALAN, NAZİF EKİN; Yücesoy, Can A.
    In cerebral palsy (CP) patients suffering pathological knee joint motion, spastic muscle's passive state forces have not been quantified intraoperatively. Besides, assessment of spastic muscle's active state forces in conditions involving intermuscular mechanical interactions and gait relevant joint positions is lacking. Therefore, the source of flexor forces limiting joint motion remains unclear. The aim was to test the following hypotheses: (i) in both passive and active states, spastic semitendinosus (ST) per se shows its highest forces within gait relevant knee angle (KA) range and (ii) due to intermuscular mechanical interactions, the active state forces elevate. Isometric forces (seven children with CP, GMFCS-II) were measured during surgery over a range of KA from flexion to full extension, at hip angle (HA) = 45 degrees and 20 degrees, in four conditions: (I) passive state, (II) individual stimulation of the ST, simultaneous stimulation of the ST (III) with its synergists, and (IV) also with an antagonist. Gait analyses: intraoperative data for KA = 17-61 degrees (HA = 45 degrees) and KA = 0-33 degrees (HA = 20 degrees) represent the loading response and terminal swing, and mid/terminal stance phases of gait, respectively. Intraoperative tests: Passive forces maximally approximated half of peak force in condition II (HA = 45 degrees). Added muscle activations did increase muscle forces significantly (HA = 45 degrees: on average by 42.0% and 72.5%; HA = 20 degrees: maximally by 131.8% and 123.7%, respectively in conditions III and IV, p < 0.01). In conclusion, intermuscular mechanical interactions yield elevated active state forces, which are well above passive state forces. This indicates that intermuscular mechanical interactions may be a source of high flexor forces in CP. (C) 2020 Elsevier Ltd. All rights reserved.
  • PublicationRestricted
    The Relationship of One Leg Standing Duration to GMFM Scores and to Stance Phase of Walking in Children with Hemiplegic Cerebral Palsy
    Background: Lack of stability during stance negatively impacts gait and motor function for children with unilateral cerebral palsy. Improving stability and balance are the focus for gait rehabilitation). The One-Leg-Standing-Test may give valuable information about motor function and stability of stance for patients with unilateral cerebral palsy. Objective: This study aimed to investigate the relationship between the One-Leg-Standing-Test and the gross-motor-function-measurement and single-limb support time. Methods: The study included 18 patients with unilateral cerebral palsy (age 11.08 [SD 2.84] years old). The One-Leg-Standing-Test and pedobarographic evaluation were performed. Sections D and E of the gross-motor-function-measurement were assessed, and in pedobarographic evaluation, the single-limb support time (the total duration of mid-stance and terminal-stance during walking) was calculated to describe stability during stance. Results: For patients, the One-Leg-Standing-Test scores and single-limb support time values were lower on the affected side than on the unaffected side. The One-Leg-Standing-Test was correlated with single-limb support time (p = .02, r = 0.60) and section E (p < .01, r = 0.59) values. The One-Leg-Standing-Test was also correlated to total stance phase and section D. Conclusion: The One-Leg-Standing-Test gives valuable information about gross-motor-function but cannot be substituted for motor function tests. The single-limb support time value may be used to describe stability in stance during walking.
  • PublicationRestricted
    Determining the Relationship Between the Impairment of Selective Voluntary Motor Control and Gait Deviations in Children With Cerebral Palsy Using Simple Video-Based Analyses
    (Elsevier Ireland Ltd., 2021) Sardogan, Cansu; Muammer, Rasmi; AKALAN, NAZİF EKİN; Sert, Rukiye; Bilgili, Fuat
    Background: The impairment of selective voluntary motor control (SVMC) in children with cerebral palsy (CP) has been shown to correlate with their gait characteristics using complex 3D gait analysis systems (3DGA); however, this relationship has not been investigated using simple video-based observational gait analysis (VBOGA). The aim of this study was to determine the relationship between VBOGA and SVMC of the lower extremities in children with CP. Methods: Forty-two CP children 10.9 +/- 5.7 years old with Gross Motor Function Classification System (GMFCS) levels I-III participated in the study. Their gait characteristics were assessed using the Edinburgh Visual Gait Score (EVGS), and selective voluntary motor control was tested using the Selective Control Assessment of the Lower Extremity (SCALE). Spearman's rho correlation test with Cohen's classification were used in the statistical analyses. Results: The GMFCS levels (r = 0.604, p < 0.001), foot clearance (r = -0.584. p < 0.001), and maximum ankle dorsiflexion (r = -0.567, p < 0.001) during the swing phase had strong correlations with total SCALE scores. There was also a moderate correlation between total SCALE scores and total EVGS (r = -0.494, p < 0.001), knee extension in the terminal swing phase (r = -0.353, p < 0.001), peak sagittal trunk position (r = -0.316, p < 0.005), and maximum lateral shift (r = -0.37, p < 0.001). Conclusion: Impaired lower extremity SVMC was noticeably related to the foot and ankle movements in the swing phase and initial stance during walking as well as the total EVGS scores and sagittal and frontal trunk movements. The SCALE correlations with VBOGA were similar those observed in the complex 3DGA in the literature; therefore, we suggest that SVMC impairment of gait could be evaluated using simple VBOGA. These findings may help to tailor physical therapy programs for CP children to increase their motor control and walking quality.
  • Publication
    Kinesiology of the Human Gait
    (Elsevier, 2020) AKALAN, NAZİF EKİN; Angın, Salih
    Gait is one of the most complex functional activity which takes 7 years in average to learn and there are many factors such as music that is listened to, momentary psychogenic state, exhaustion, happiness, anger, etc. may affect the gait characteristics. Gait is a common activity in our daily lives. People who experience pain in only one phase of gait do not feel it only once a day. This situation is unacceptable for the human body and, thus, causes automatic, compensatory changes in a short time. In this section, the fundamentals of normal gait, its sub-phases, and the biomechanical events under these phases are explained.
  • PublicationOpen Access
    Time Difference Between Onsets of Lateral and Medial Hamstring Muscles During Gait in Patients With Patellofemoral Pain: A Preliminary Study
    (Marmara Univ., Inst Health Sciences, 2022) Coşkunsu, Dilber Karagözoğlu; Can, Filiz; Kuchimovs, Shavkat; AKALAN, NAZİF EKİN; Kılıçoğlu, İ. Önder; Öztürk, Necla
    Objective: Early activation of lateral hamstrings (LH) relative to medial hamstrings (MH) has been thought to be the cause of abnormal knee abduction and external rotation of the tibia, which affects the orientation of patellar tendon and increases lateral patellofemoral compression. Therefore, early activation of LH relative to MH is considered to have a role in the patellofemoral pain (PFP). The aim of this study was to investigate the time difference between MH and LH onsets in patients with PFP during gait. Methods: Thirteen patients with bilateral PFP (mean age 28.73 +/- 7.44 years) and 13 asymptomatic subjects (mean age 30.47 +/- 6.22 years) were recruited in the study. Gait analysis was performed using the ELITE system (BTS, Milano-Italy) with video cameras (TVC, BTS, Milano-Italy). Participants were requested to walk at a self-selected speed on a force platform, and EMG data were recorded from MH and LH muscles for 10 initial contacts by using TELEEMG (BTS, Milano-Italy). Time difference between the onsets of the MH and LH was calculated for each initial contact by using moving averaging method, then their mean was obtained for each participant. Results: The time difference between onsets of MH and LH was - 26.9 +/- 22.2 ms for PFP subjects and - 11.2 +/- 14.2 ms for control subjects, and LH mainly became activated earlier compared to MH in most of the subjects in both groups. There was a statistically significant difference between the time differences of the groups (p=0.041). Conclusion: Our findings suggest that LH displayed an earlier activation in subjects with PFP compared to control subjects during gait.