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Now showing 1 - 10 of 17
  • Publication
    ESMAC 2021 Abstracts
    (Elsevier Ireland Ltd., 2021) AKALAN, NAZİF EKİN; GÖRGÜLÜ, M.; AYDIN, B.; Sert. R.; Bilgili F.
  • Publication
    Yürüme esnasındaki gövde-baş açısı ölçümü için kablosuz çift ivmeölçerli giyilebilir sistem
    (IEEE, 2018) AKALAN, NAZİF EKİN; GÜRKAN, GÜRAY; ÖNERGE, KÜBRA; 113297; 283338; 176320
    Literatürde, yere bakarak yürümenin yürüme parametrelerini ve ayak basıncını değiştirebileceği ile ilgili bilindik bir çalışma bulunmamaktadır. Bu çalışmada, yürüme esnasında gövde-baş açı değişimini ölçebilen bir sistem sunulmaktadır. Sistemin donanım kısmı, oksipital ve sırt bölgelerine yerleştirilen iki adet 3 eksenli sayısal ivmeölçer, mikroişlemci, Bluetooth modülü ve bataryadan oluşmaktadır. Mikroişlemcinin aldığı ivme verisi Bluetooth aracılığı ile alıcı bilgisayara gönderilmektedir. Verinin alınması, açı kestiriminin yapılması ve görselleştirilmesi, sistemin yazılım kısmını oluşturan ve Python dilinde geliştirilen kullanıcı arayüzü ile yapılmaktadır. Geliştirilen sistem hem iki serbestlik dereceli bir kol üzerinde hem de yürüme sırasında bir kullanıcı üzerinde test edilmiştir.
  • PublicationOpen Access
    Does Increased Femoral Anteversion Can Cause Hip Abductor Muscle Weakness?
    Background: Increased femoral anteversion (IFA) causes functional problems (i.e., tripping, frequently falling, and fatigue) by affecting the pelvis and lower extremity biomechanics. In the frontal plane, increased contralateral pelvic drop and ipsilateral hip adduction, which are mainly considered deteriorated hip abductor muscle mechanisms, are associated with hip and knee injuries. Aims: The aim of this study was to examine the effects of femoral anteversion on hip abductor weakness and frontal plane pelvis-hip biomechanics during walking. Methods: The study included nine subjects with increased femoral anteversion and a control group of eleven subjects. Maximum isometric voluntary contraction (MIVC) values of the hip abductor muscles were measured with a handheld dynamometer. Three-dimensional gait analysis was performed for kinetic, kinematic, and temporo-spatial gait parameters. Non-parametric tests were used for statistical analysis (p < 0.05). Results: There was no significant difference found between the MIVC values of the IFA and control groups (p = 0.14). Moreover, no significant difference was determined between the ipsilateral peak hip adduction (p = 0.088) and contralateral pelvic drop (p = 0.149) in the stance phase. Additionally, there was no correlation between the peak hip adduction angle in the stance phase and normalized MIVC values in the IFA group (r = -0.198, p = 0.44), or in the control group (r = -0.174, p = 0.55). The deviations of pelvic rotation (p = 0.022), hip internal rotation (p = 0.003), and internal foot progression (p = 0.022), were found to be higher in the IFA group than in the controls. Conclusions: IFA may not be associated with hip abductor muscle weakness, and it may not lead to the hip adduction and pelvic depression that can be seen in hip abductor weakness. Increased pelvic rotation and internal hip rotation during walking might be considered as a compensation for the femoral head-acetabulum alignment mechanism in the frontal plane.
  • PublicationRestricted
    Increased Femoral Anteversion May Not Cause Hip Abductor Muscle Weakness During Walking
    (Elsevier Ireland Ltd., 2023) APTİ, ADNAN; AKALAN, NAZİF EKİN; KUCHIMOV, SHAVKAT; Temelli, Yener
  • 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.
  • PublicationEmbargo
    O 043 – Mechanics of spastic semitendinosus altered by intermuscular interactions elevate its contribution to pathological resistance against knee extension during gait
    (2018-09) Kaya, C.S.; Bilgili, Fuat; Temelli, Yener; Ateş, Filiz; Yücesoy, Can A.; AKALAN, NAZİF EKİN
  • Publication
    Pilot Study on Obstetric Brachial Plexus Paralysis: Docs Arm Swing Asymmetry Affect Foot Plantar Pressure Behavior?
    (2019-09) Kuchimov, Shavkat Nadir; AKALAN, NAZİF EKİN; 176320
    Introduction Brachial plexus palsy, as one of the most common congenital injuries affected by arm swing, is characterized by muscle weakness at different levels in the upper extremity (1). As the weakness of the upper extremity muscles can affect the trunk muscles and the postural development, these children may have some gait deviations (2,3). Previous studies have shown that walking parameters are also influenced by clinical conditions such as stroke and cerebral palsy (2-6). There is a lack of literature on determining the biomechanical influences of arm swing asymmetry on foot pressure behavior for OBBP children. Therefore, the aim of the study was determining arm-swing asymmetry related foot pressure behavioral alterations on OBBP. Research Question Does arm swing asymmetry affect foot plantar pressure behavior on OBBP patients? Methods Thirteen children with OBPP (7 females, 6 males) (mean age:9.37±2.68 years) participated in the study. For all individuals, a digital plantar-pressure analysis system (Win-track, Balma, France) was utilized to analyze the foot pressure behavior during standing and walking with self-selected velocity. The magnitude of the first and the second peak forces divided to an invidual’s weight (Fl, F2), total stance duration (Ts), time of Fl (Tl), time of min force between F1-F2 (T2), time o f F2 (T3), step length were calculated. Each stance phase was divided into five sub-phases: Loading response (Tl/Ts), mid-stance (T2-Tl/Ts), terminal stance (T3-T2/Ts) and pre-swing (Ts-T3/Ts), single limb support (T3-Tl/Ts) (7). In addition, arm swing ranges were recorded and analyzed using Kinovea software (8). Paired t-test was used for the compared between affected side and non-affected side (p < 0.05). Results Fl, pre-swing duration and step length were higher in affected side than in non-affected side(p<0.05). Single limb support duration lower in affected side than in non-affected side (p<0.05). The maximum arm flexion and extension angle and arm swing range were significantly reduced on the affected side (p<0.05). No significant difference was found in F2, loading response duration, mid-stance duration and terminal stance duration between affected side and non-affected side (Table 1). Discussion The reduced arm swing may alter the foot pressure behavior during walking on affected side as well as the non-affected side in children with OBBP. Reduced single limb support duration ((T3-Tl)/Ts) on the affected side indicate the stability problem in stance on affected side. Increase the first vertical peak force (Fl) on the affected side is probably related to the decreased arm extension range at the affected side, which absorbs the first peak of vertical force in early stance during walking. Increased step length on the affected side may due to the enhanced single limb duration on the non-affected side.
  • Publication
    Femoral Anteversiyon Artışı Olan Çocuklarda Hipermobilite, Kas Kuvveti ve 3 Boyutlu Yürüme Analizi Parametreleri Arasındaki İlişki
    (2019-10-18) EVRENDILEK, HALENUR; Karaca, Gülşah; Ertürk, Gamze; Bilgili, Fuat; AKALAN, NAZİF EKİN; ÖNERGE, KÜBRA
    AMAÇ Çalışmanın amacı; femoral anteversiyon artışı (FAA) olan çocuklarda hipermobilite, kas kuvveti ve 3 boyutlu yürüme analizi parametreleri arasındaki ilişkiyi araştırmaktır. YÖNTEM FAA olan 7 çocuk (14 bacak, ort.yaş:9.14 ± 0.3, trokanter prominens açı testi(TPAT):28 ± 6.2°) çalışmaya dahil edildi. Çocukların femoral anteversiyon açıları, eklem mobiliteleri ve maksimal izometrik kas kuvvetleri sırasıyla TPAT, Beighton testi ve el dinamometresiyle (Lafayette Instruments,USA) değerlendirildi. Tüm katılımcılara normal hızlarında yürürken 3 boyutlu yürüme analizleri yapılarak pelvis, kalça ve diz kinematik parametreleri incelendi. Parametreler arasındaki ilişkiler, verilerin normal dağılımlarına göre Pearson ve Spearman korelasyon testleri kullanılarak değerlendirildi. Verilerin istatistiksel olarak anlamlılık düzeyi (p<0.05) olarak kabul edildi ve sonuçlar Cohen sınıflamasına göre yorumlandı. BULGULAR Beighton testi skoru ile kalça ekstansör(r: -.70) ve diz ekstansör(r: -.91) kas kuvvetleri, minimum diz fleksiyon açısı(r: -.83) arasında yüksek korelasyon bulundu. TPAT değerleri ise kalça abduktör kas kuvveti(r: -.77) ve ortalama kalça rotasyon açısıyla yüksek korelasyon gösterdi(r: .60). TARTIŞMA Literatürde, FAA olan çocukların yürüme sırasında ortalama kalça iç rotasyon, pelvik oblikite ve duruş fazında diz ekstansiyon parametrelerinin arttığı gösterilmiştir. Bu çalışma, zayıf kalça ekstansör ve abduktür, diz fleksör ve ekstansör kaslarındaki zayıflığın kinematik değişimlerle ilişkili olabildiğini göstermiştir. Ayrıca, literatürle uyumlu olarak ortalama kalça internal rotasyon parametresiyle kalça abdüktör kas kuvvetinin TPAT açısıyla anlamlı olarak ilişkili olduğu bulumuştur. FAA olan çocuklarda sıkça görülebilen hipermobilitenin, kalça ve diz ekstansör kas zayıflığı ile duruş fazında hiperekstansiyon artışında rolü olabilir. Sonuç olarak, kalça abdüktör ve ekstansör, diz fleksör ve ekstansör kas kuvvetlerinin arttırılması, FAA olan hipermobil çocuklarda alt ekstremite fonksiyonun iyileştirilmesi için önemlidir.
  • 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.