Jiří Chomiak
Charles University in Prague
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Journal of Bone and Joint Surgery, American Volume | 2009
Jiří Chomiak; Martin Horák; Martin Masek; Monika Frydrychová; Pavel Dungl
BACKGROUND Because there is limited information concerning the vascular pattern and the role of vessels in patients with proximal femoral focal deficiency, the vascular supply of the lower extremities was studied systematically with use of computed tomographic angiography in order to identify vascular changes, relate any vascular changes to the classification of the deficiency, and establish that there are no major changes in the topographical anatomy of the vessels. METHODS Standardized computed tomographic techniques were used in twenty-one patients (thirteen boys and eight girls who ranged from one to nineteen years old) with proximal femoral focal deficiency types I through IV and VII, VIII, and IX, according to the Pappas classification. RESULTS A common anatomical vascular pattern, in which the hypoplastic extremity was supplied through the femoral artery, was detected in nineteen patients. In patients with Pappas type-I through IV disease, the external iliac, femoral, and deep femoral arteries were substantially reduced in length and diameter and the deep femoral artery arose more proximally in comparison with that in the contralateral extremity; however, in the patients with Pappas type-VII, VIII, or IX disease, the diameters of the arteries and the origin of the deep femoral artery were similar to those of the contralateral extremity. In two patients with Pappas type-III disease, atypical anatomy of the vessels was found. The anterior part of the thigh and the pseudarthrosis were supplied through the femoral artery (the external iliac artery) as a terminal branch, while the remainder of the extremity was supplied from the internal iliac artery, which entered the thigh posterior to the hip as the inferior gluteal artery and continued as the artery to the sciatic nerve to the popliteal artery. No substantial anastomoses were found between the femoral and the posterior arteries in these vascular patterns. CONCLUSIONS Computed tomographic-angiographic reconstruction can be used to depict the spatial configuration of the pseudarthrosis and the vascular pattern of the extremity in patients with proximal femoral focal deficiency. We found distinct vascular changes in the majority of the involved thighs, but there were no typical changes related to the Pappas classification. Because we found atypical vascular patterns in two patients, evaluation of the vessels with use of various diagnostic methods is recommended in patients with severe types of proximal femoral focal deficiency.
Journal of Pediatric Orthopaedics | 2012
Jiří Chomiak; Aleš Podškubka; Pavel Dungl; Martin Oštʼádal; Monika Frydrychová
Background: Because there is limited information concerning the cruciate ligaments in proximal femoral focal deficiency, knee arthroscopy was used to identify the changes of cruciate ligaments and their relation to the different types of this deficiency. Methods: Knee arthroscopy was performed in 21 consecutive patients with deficiency types III, IV, VII-IX using the Pappas classification. A new classification of the knee was created. It contains types I, II, III according to the findings of the anterior cruciate ligament (ACL) (type I: normal, type II: hypoplasia, type III: aplasia) and 3 subtypes A, B, C according to the findings of the posterior cruciate ligament (PCL) (type A: normal, type B: hypoplasia, type C: aplasia), respectively. Instrumented and radiologic drawer testing was provided additionally in 2010. Results: The changes of the cruciate ligaments were found in all but 1 patient. Type I was found in only 2 patients. In 1, both cruciate ligaments were intact (type IA). In the other patient, the ACL was intact, but the PCL was absent (type IC). Hypoplastic ACLs (type II) were found in 4 patients, namely in 3 patients with normal PCLs (type IIA), whereas in 1 patient the PCL was absent (type IIC). In the majority of patients, the ACLs completely failed (type III, 15 patients). Absence of both cruciate ligaments was found in 8 patients (type IIIC). PCLs were intact in 4 patients (IIIA) or were hypoplastic in 3 patients (IIIB), respectively. Instrumental drawer testing was not reliable in patients of our group. Radiologic testing showed a posterior shift of the tibia in the majority of patients on the affected side. Anterior and posterior drawer tests were increased in a majority of patients, but did not directly correlate to the presence/absence of cruciate ligaments. Conclusions: Variable changes of the cruciate ligaments were found in all but 1 patient with proximal femoral focal deficiency. These changes were not related to the type of Pappas classification. Despite the lower clinical relevance of the changes in majority of patients, imaging of cruciate ligaments is recommend before lengthening of the extremity to avoid dislocation of the knee. Level of Evidence: I – Testing of previously developed diagnostic criteria in series of consecutive patients.
Hip International | 2015
Jiří Chomiak; Jiří Huráček; Jiří Dvořák; Pavel Dungl; Radovan Kubeš; Ondřej Schwarz; Urs Munzinger
Purpose Three surgical approaches in total hip arthroplasty (THA) were compared concerning: 1) clinical and radiological results; 2) innervation of the tensor fasciae latae and gluteal muscles; 3) clinical outcome of the nerve lesions; 4) sensitivity of the EMG analysis. Methods A total of 70 patients aged 39-79 years were evaluated clinically and electromyographically before and 3-9 months after THA in 2 centres using the anterolateral approach in 22, transgluteal approach in 33 and posterior approach in 15 patients, respectively. Results 1) Hip flexion, external rotation and Trendelenburg lurch were reduced and the centre of the rotation was higher after the anterolateral approach. 2) The inferior branch of the superior gluteal nerve of the tensor fasciae latae muscle was mostly damaged in the anterolateral approach (73% of lesions), whereas innervations of gluteus medius (9% of lesions) and maximus muscles (no lesion) were preserved. The transgluteal approach most often caused a partially denervated gluteus medius (81.8%) and the tensor fasciae latae (48%) and the gluteus maximus muscle only in 29%, respectively. After the posterior approach, partial denervation in the gluteus medius and maximus muscles were noted in 53.3% and 71.4%, respectively, whereas in the tensor fasciae latae muscle in only 14%. 3) The power of the abductors was not significantly reduced in partially denervated muscles. 4) The EMG examination is not sensitive enough to determine the relevant power of hip abductors. Conclusions Despite some disadvantages associated with the anterolateral approach, the transgluteal and posterior approaches are often connected with a partial lesion of the gluteus medius and maximus muscles. In all approaches, clinical sequelae are not significant in primary THA.
Molecular and Cellular Biochemistry | 2015
Martin Ošt’ádal; Adam Eckhardt; Jan Herget; Ivan Mikšík; Pavel Dungl; Jiří Chomiak; Monika Frydrychová; Michal Burian
Abstract Idiopathic pes equinovarus is a congenital deformity of the foot and lower leg defined as a fixation of the foot in adduction, supination, and varus. Although the pathogenesis of clubfoot remains unclear, it has been suggested that fibroblasts and growth factors are involved. To directly analyze the protein composition of the extracellular matrix in contracted tissue of patients with clubfoot. A total of 13 infants with idiopathic clubfoot treated with the Ponseti method were included in the present study. Tissue samples were obtained from patients undergoing surgery for relapsed clubfeet. Contracted tissues were obtained from the medial aspect of the talonavicular joint. Protein was extracted after digestion and delipidation using zip-tip C18. Individual collagenous fractions were detected using a chemiluminescent assay. Amino acid analysis of tissue samples revealed a predominance of collagens, namely collagen types I, III, and VI. The high content of glycine and h-proline suggests a predominance of collagens I and III. A total of 19 extracellular matrix proteins were identified. The major result of the present study was the observation that the extracellular matrix in clubfoot is composed of an additional 16 proteins, including collagens V, VI, and XII, as well as the previously described collagen types I and III and transforming growth factor β. The characterization of the general protein composition of the extracellular matrix in various regions of clubfoot may help in understanding the pathogenesis of this anomaly and, thus, contribute to the development of more efficacious therapeutic approaches.
Journal of Pediatric Orthopaedics | 2014
Jiří Chomiak; Pavel Dungl; Josef Vcelak
Background: The purpose of this study was to analyze the results of a pectoralis major transfer to restore active elbow flexion in patients with extension elbow contracture in arthrogryposis. The hypotheses were: (1) this transfer ensures permanent useful elbow flexion; and (2) flexion elbow deformity will not progress during growth and after its cessation. Methods: Unipolar transfer of the 3 distal parts of the pectoralis major muscle was used in 9 extremities of 5 patients (age range, 5 to 9 y; average age, 6.3 y) and the results were prospectively followed in the period of 13 to 16 years. Posterior elbow release was necessary in 5 extremities to achieve passive flexion of 90 degrees before the transfer. The subjective evaluation of daily living activities and data on the physical examination of the range of movement of the elbow, muscle strength, and electrical activity of the transferred muscle were assessed. Two specimens from transferred muscles were histologically examined. Results: All extremities achieved the active elbow flexion. Significant improvement of function for daily living activities was achieved in 5 extremities (55.5%). It includes the following results: 1 very good with flexion of 90 degrees and a deficit of extension of 35 degrees; 2 good with flexion of 92 and 100 degrees and a lack of extension of 42 and 45 degrees; and 2 satisfactory with a limited arc of motion between 20 and 45 degrees. Four extremities remained unsatisfactory with the arc of motion of 5 to 15 degrees. Significant elbow flexion contracture of 70 to 80 degrees developed in 4 extremities. Extremities with a necessity of posterior elbow release achieved a limited range of movement or significant elbow flexion contracture. Electromyography corresponded to a partial denervation of the transferred muscle followed by reinervation. Histologic examinations showed partial atrophy with signs of ongoing regeneration. Conclusions: The hypotheses of the study were not confirmed, because this muscle transfer restores useful elbow flexion without flexion deformity if the passive flexion at children’s age exceeds 90 degrees without a necessity of posterior release. In these cases, bilateral pectoralis to biceps transfer is recommended. Level of Evidence: Level II.
Prague medical report | 2017
Karel Medek; Jiří Zeman; Tomas Honzik; Hana Hansikova; Štěpánka Švecová; Kamila Beránková; Vendula Kučerová Vidrová; Miloslav Kuklík; Jiří Chomiak; Markéta Tesařová
Hereditary multiple exostoses (HME) represents a heterogeneous group of diseases often associated with progressive skeletal deformities. Most frequently, mutations in EXT1 and EXT2 genes with autosomal dominant inheritance are responsible for HME. In our group of 9 families with HME we evaluated the clinical course of the disease and analysed molecular background using Sanger sequencing and MLPA in EXT1 and EXT2 genes. The mean age in our group of patients, when the first exostosis was recognised was 4.5 years (range 2-10 years) and the number of exostoses per one patient documented on X-ray ranged from 2 to 54. Most of the exostoses developed before the growth was completed and they were dominantly localised in the distal femurs, proximal tibia, proximal humerus and distal radius. In all patients, at least one to 8 surgeries were necessary due to complaints and local complications, but neither patient developed malignant transformation. In half of the patients, the disease resulted in short stature. DNA analyses were positive in 7 families. In five probands, different EXT1 gene mutations resulting in premature stop-codon (p.Gly124Argfs*65, p.Leu191*, p.Trp364Lysfs*11, p.Val371Glyfs*10, p.Leu490Profs*31) were found. In two probands, nonsense mutations were found in EXT2 gene (p.Val187Profs*115, p.Cys319fs*46). Five mutations have been novel and two mutations have occurred de novo in probands. Although the risk for malignant transformation is usually low, especially in patients with low number of exostoses, early diagnostics and longitudinal follow up of patients is of a big importance, because early surgery can prevent progression of secondary bone deformities.
Acta Chirurgiae Orthopaedicae Et Traumatologiae Cechoslovaca | 2002
Adamec O; Pavel Dungl; Kasal T; Jiří Chomiak
International Orthopaedics | 2014
Josef Vcelak; Jiří Chomiak; Ladislav Tóth
International Orthopaedics | 2014
Jiří Chomiak; Pavel Dungl; Martin Ošťádal; Monika Frydrychová; Michal Burian
Hip International | 2007
Pavel Dungl; M. Rejholec; Jiří Chomiak; Franz Grill