Vertebral Motion Segment Research Articles

Conservative Treatment of Cervicobrachial Syndrome in Patients with Cervical Osteochondrosis (Literature Review)

The article analyzes the data of 58 sources of literature on the treatment of cervicobrachial syndrome in patients with cervical osteochondrosis. The anatomical and topographic features of the cervical spine, which are predisposing factors for the development of the studied pathology, namely, the small size of the vertebral bodies and their increased mobility are noted in the work. A high incidence of degenerative-dystrophic diseases of the cervical spine was found in persons over 60years old (50 %) and aged 60years and older (75 %) with a predominance of the development of the pathological process at the level of the C V -C VI vertebral motor segment. According to the literature, the attitude to the problem of treating this pathology is contradictory. The main points of application of conservative treatment are the elimination of pain and muscle spasm, an increase in the volume of movements in the cervical spine. Despite the fact that significant progress has been achieved in recentyears in conservative treatment of patients with pathology of the cervical spine, many tasks remain unresolved and require further analysis, and therefore the problem of improving diagnosis and treatment remains relevant, socially significant and timely.

The classifications of subaxial cervical spine traumatic injuries. Part 1. General principles

Cervical spine and spinal cord injury is a significant medical and socio-economic problem of modern society. Ongoing urbanization, the development of high-speed modes of transport and the intensification of military conflicts lead to a progressive increase in the number of victims with this pathology. At the same time, unlike several other socially significant diseases, the category of the most employable population suffers from spinal injuries. Achievements of modern medicine to a much greater extent contribute to reducing the mortality of patients, rather than regression of neurological disorders. The usage of new diagnostic methods for neuroimaging and expensive surgical instruments, the continuous improvement of rehabilitation treatment of patients with spinal cord injury determine the progressively increasing costs for medical and social life support expenses. A large number of experimental and clinical studies, improvement of methods for surgical correction and stabilization of the damaged vertebral motor segment undoubtedly dictate certain changes in the tactics of treatment. The classification of traumatic spinal injuries is of key importance in determining the approaches, timing and volume of surgical intervention. Following the care algorithms helps to minimize the negative effects of traumatic damage to both the spine and the spinal cord and contributes to the maximum possible recovery of neurological functions. The last few decades have been characterized by the gradual replacement of the previously widely used “morphological” classifications of traumatic injuries of the cervical spine to “clinical” ones, based on an analysis of some heterogeneous factors determining treatment tactics. The first part of the review deals with a detailed description of the main criteria used in developing modern “clinical” classifications of subaxial cervical spine traumatic injuries. Besides, modern views on imaging methods and algorithms for determining the need to perform diagnostic procedures at primary hospitalization in patients with suspected cervical spine traumatic injury are presented.

Clinical features and complex treatment of vertebral thoracalgia with neurodystrophic signs

Objective — to identify the clinical features of vertebral thoracalgia (VT) with neurodystrophic signs and to increase the effectiveness of their complex treatment using manual therapy and kinesiotherapy.Methods and subjects. 247 patients who had VT with neurodystrophic manifestations were under our observation and treatment. The main group included 178 patients with VT (72.1 %) and they were given a complex therapy according to standards and protocols; manual therapy (MT) and kinesiotherapy were applied additionally. The comparison group consisted of 69 patients with VT (27.9 %) who received similar treatment, but without MT.Results. On manual muscle testing results vertebral neurological features were identified in patients with thoracalgia with neurodystrophic manifestations. The nodes of neuroosteofibrosis and neuromiofibrosis as well as functional blocking of the vertebral motor segment (VMS) were determined at several levels in all patients and blocking of additional joints in 90.4 % of patients. As a result of complex treatment with the use of MT in patients from the main group, 108 people (60.7 %) were discharged with significant improvement, 47 (26.4 %) with improvement, in the comparison group, where MT was not used — 22 (31.9 %) and 12 (17.4 %) patients respectively. A slight improvement was observed in 23 patients (12.9 %) from the main group and in 11 (15.9 %) patients from the comparison group. 24 patients (34.8 %) from the comparison group were discharged without improvement. The average treatment periods in the main group were 14.3 ± 1.5 days, and in the comparison group 19.6 ± 2.2 (р < 0.05).Conclusions. In all VT patients with neurodystrophic signs, a manual diagnosis reveals the functional blocks of the thoracic VMS and the nodes of the neuroosteo‑and neuromiofibrosis. At the same time, in 42.6 % of patients, VMS were blocked at several levels, and 90.4 % of patients had blocking of additional joints. The inclusion of MT in the complex treatment significantly increases its effectiveness and reduces the duration of treatment.

A rare clinical case of surgical treatment of a periarticular cyst of the facet joint of the lumbar spine

Background. Periarticular cysts of the facet joint, due to their rare occurrence, often slip away from the attention of clinicians. However their formation and progression may cause compression of vascular-neural structures with subsequent manifestations of severe neurological disorders.
 Description of the clinical case. We present a rare clinical case of surgical treatment of a periarticular cyst of the facet joint. A comprehensive examination of the patient S. revealed: Dorsopathy with degenerative spinal canal stenosis at LV-SI level; spondyloarthrosis; periarticular facet cyst at LV-SI level on the left; radiculopathy LV on the left, in the acute stage; pronounced pain and musculo-tonic syndrome. Complaints of the patient: constant pain in the lumbar spine, extending to the left lower extremity and aggravating when walking at a distance of 50-100 meters; feeling numb when walking on the plantar surface of the left foot. When examining the local status, a forced posture with a bowed head and torso forward was noted; smooth lumbar lordosis and antalgic right-sided scoliosis; tension of paravertebral muscles. Neurological examination revealed LVradiculopathy on the left with moderate paresis of the extensor muscles of the left foot and ipsilateral Lasègue's positive test. MRI examination revealed spinal canal stenosis, facet joint cyst at the level of LV-SI with dimensions of 14×8×8.5 mm. An operative intervention was performed: reconstructive decompressive-stabilizing spinal surgery with a single block removing the articular facet with a periarticular cyst at the left LV-SI level with subsequent posterior transpedicular fixation of the vertebral motor segment. Two months after the operation, complete medical and social rehabilitation of the patient was achieved. No complaints.
 Conclusion. In case of compression of a periarticular cyst of vascular-neural structures with severe neurological disorders, surgical treatment with the cyst removal is recommended.

Internal and external sagittal craniovertebral alignment: A comparison between radiological and photogrammetric approaches in asymptomatic participants

BackgroundPhotogrammetric measures are a commonly applied, highly reliable tool for appraising craniovertebral postures during clinical assessments, rehabilitation, and research interventions. ObjectiveThis study aimed to compare and contrast three external measures of postural alignment (EMPA) using photogrammetric and radiological approaches, and to discuss whether the craniovertebral angle (CVA) reflects the shape of the underlying cervical spine. DesignCross Sectional Correlation Study. MethodYoung adults attended three assessment sessions (S1, S2 and S3). S1 involved a standardised photogrammetric protocol. S2 involved radiographic image acquisition. S3 followed the same protocol in S1 but excluded the self-balancing procedure. Each session's EMPA were compared through either paired or independent samples t-tests. The different radiographic cervical subtypes and their corresponding CVAs were assessed. ResultsThere were no significant differences in any EMPA between the two photogrammetric sessions. The CVA was the only EMPA to show a significant difference between photogrammetric (S3) and radiographic approaches. Cervical subtype variability is present throughout the full CVA range. ConclusionsDespite the statistically significant difference in the CVA between approaches, the mean difference was small and unlikely to be clinically meaningful. Accordingly, the quantification of EMPA can be undertaken with high levels of precision and reliability using standardised photogrammetric procedures. The CVA, however, does not provide an indication of the shape of the underlying cervical spine. The distinct radiological differences in the inter-segmental orientation of each vertebral motion segment in conjunction with the differences in the overall global cervical alignment, both within and between participants, negate this possibility.

Age features of structural rearrangements of the vertebral motor segment in conditions of limited motor activity

Age features of structural rearrangements of the vertebral motor segment in conditions of limited motor activity

Вікові особливості структурних перебудов хребетно-рухового сегменту в умовах обмеженої рухової активності

Andrii Sak & Raisa Antipova Purpose : o study in the age aspect structural changes of the lumbar intervertebral discs and adjacent structures of the spine of rats with limited motor activity to determine the patterns of their restructuring under conditions of experimental hypokinesia. Material & Methods: study was performed in an experiment on male Wistar rats of different ages. The hypokinesia regimen was achieved by keeping animals in small cells, which restricted movement. The research methods included morphometry, macro- and microscopy, standard histology methods with hematoxylin-eosin and picrofuchsin staining according to Van Gieson, as well as statistical analysis of the data were obtained. Results: it is determined that the restriction of mobility contributed to the change of all parts of the vertebral motor segment. The shape and linear dimensions of the intervertebral discs change, the level of its diffuse feeding from the vertebral bodies decreases. Conclusions: it has been established that the absence of mechanical stimulation of intervertebral disks, in the mode of experimental hypokinesia, reduces the level of metabolism in cells, inhibits the processes of adaptive tissue remodeling and contributes to the disruption of intact structures.

Mechanical behavior of metastatic vertebrae are influenced by tissue architecture, mineral content, and organic feature alterations.

Diminished vertebral mechanical behavior with metastatic involvement is typically attributed to modified architecture and trabecular bone content. Previous work has identified organic and mineral phase bone quality changes in the presence of metastases, yet limited work exists on the potential influence of such tissue level modifications on vertebral mechanical characteristics. This work seeks to determine correlations between features of bone (structural and tissue level) and mechanical behavior in metastatically involved vertebral bone. It is hypothesized that tissue level properties (mineral and organic) will improve these correlations beyond architectural properties and BMD alone. Twenty-four female athymic rats were inoculated with HeLa or Ace-1 cancer cells lines producing osteolytic (N = 8) or mixed (osteolytic/osteoblastic, N = 7) metastases, respectively. Twenty-one days post-inoculation L1-L3 pathologic vertebral motion segments were excised and μCT imaged. 3D morphometric parameters and axial rigidity of the L2 vertebrae were quantified. Sequential loading and μCT imaging measured progression of failure, stiffness and peak force. Relationships between mechanical testing (whole bone and tissue-level) and tissue-level material property modifications with metastatic involvement were evaluated utilizing linear regression models. Osteolytic involvement reduced vertebral trabecular bone volume, structure, CT-derived axial rigidity, stiffness and failure force compared to healthy controls (N = 9). Mixed metastases demonstrated similar trends. Previously assessed collagen cross-linking and proline-based residues were correlated to mechanical behavior and improved the predictive ability of the regression models. Similarly, collagen organization improved predictive regression models for metastatic bone hardness. This work highlights the importance of both bone content/architecture and organic tissue-level features in characterizing metastatic vertebral mechanics. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:3013-3022, 2018.

PERIARTICULAR CYSTS OF FACET JOINTS: ETIOPATHOGENESIS, DIAGNOSIS, METHODS OF SURGICAL TREATMENT. A CLINICAL EXAMPLE

Background. Periarticular cysts (PC) of facet joints is a rare pathology in neurosurgical practice. The concept of PC is applicable for all cysts that are located either pararticularly in the region of facet joints, or start from them.Material and methods. A systematic search was performed in medical databases: Medline, RINC, EMedicine, UMKB, Pubmed on the relevant topic in Russian and English. The search query includes words: arcuate joint, periarticular cyst, clinic, diagnosis, surgical treatment. One of the significant factors of PC development is the instability of the vertebralmotor segment of both degenerative and post-traumatic character.Results. The result of the literature review was the writing of a clinical lecture, the current state of the issue of etiopathogenesis, diagnosis and management of patients with periarticular cysts of facet joints was studied. The article gives a clinical example of surgical treatment of a patient with a periarticular cyst at the level of LIV-LV on the right.Conclusion. Periarticular cysts of facet joints are one of the factors of compression of cauda equina roots, with surgical treatment being a radical and effective way of treatment. A detailed study of this pathology is a promising direction in spinal neurosurgery. Further research is required on comparative analysis of clinical and instrumental efficacy of various methods of surgical treatment of periarticular cysts of facet joints.

Damage to vessels and retroperitoneal organs during lumbar spine surgery through the posterior approach

The study objective is to summarize the existing literature and own experience related to damage to vessels, retroperitoneal organs, and abdominal organs during lumbar spine surgery through the posterior approach, as well as to identify risk factors associated with this damage and to describe measures for their elimination and prevention.Materials and methods. In addition to analyzing the research literature, we also described 9 cases (3 males and 6 females; mean age 52 ± 9 years) of intraoperative damage to vessels and adjacent organs during lumbar spine surgery for some degenerative disease, including herniated disc (n = 7), anterolisthesis (n = 1), and vertebral-motor segment instability (n = 1). The surgery was performed at the L4–L5 level (n = 7) and L5–S1 level (n = 2). Results. The damages observed in the cohort analyzed were caused by a conchotome (n = 6), transpedicular screw (n = 1), Volkmann spoon (n = 1), and a tip of the SpineJet Hydrodiscectomy System (n = 1). The following structures were damaged; left common iliac vein (n = 2), left common iliac artery (n = 2), left common iliac vein and root of the small-bowel mesentery (n = 1), sigmoid colon (n = 1), aorta (n = 1), inferior vena cava (n = 1), and aortocaval anastomosis (n = 1). Five patients had intraoperative hemorrhagic complications. Four patients were found to have damage to vessels or abdominal organs later (1 h, 2 h, 3 days, and 4 months postoperatively). Four patients were discharged without consequences; 2 patients became disabled; 3 patients died.Conclusion. Damage to vessels, retroperitoneal organs, and abdominal organs during lumbar spine surgery through the posterior approach is a rare, but mortally dangerous complication. Spine surgery should be performed in multi-unit hospitals that have a surgery unit, a vascular surgery unit, an intensive care unit, and a sufficient supply of blood for transfusion.

FEATURES OF IMAGING FINDINGS IN CHILDREN WITH CONGENITAL THORACIC SPINE DEFORMITY ON THE BACKGROUND OF MALSEGMENTATION OF VERTEBRAE LATERAL SURFACE

Purpose — to study alterations in the bony structures in cases of congenital deformity of the thoracic spine combined with malsegmentation of lateral surfaces of vertebrae due to pathological processes during growth period of childern and to find correlation with above alterations.Material and Methods. The study included 30 patients with congenital deformity of thoracic spine combined with malsegmentation of lateral surfaces of vertebrae. age of patients ranged from 3 to 10 years (mean of 7 years). gender distribution — 19 female and 11 male patients. all patients underwent imaging examination including spine roentgenography in two standard views in prone position as well as computer tomography.Results. Magnitude of deformity scoliotic curve was 67° (45–88°) and of pathological thoracic lordosis — 23° (18–27°). Mean number of block vertebral motion segments included into the main deformity curve was 6 (3–8). Mean distance between the outline of lateral vertebral surface and lateral outline of projection of curve root of apical vertebra on convex side of deformity (aB) was 6 mm (4–10 mm). correlation analysis demonstrated that aB distance mostly depended on the number of vertebral motion segments included into the block along non-segmental area: pearson coefficient 0.67. Based on cT scans the authors observed no rotation component of bodies’ deformity along the non-segmental area.Conclusion. Children with congenital thoracic spine deformity along with malsegmentation of lateral surfaces of vertebrae feature pathological lordosis in affected zone. alterations in the bony structures result from asymmetric growth of one half of the vertebral body at the level of non-segmentation. asymmetry severity has a strong correlation dependency from the number of vertebral bodies included in the block along the non-segmental area.

DEGENERATIVE SPINE INJURY ASSOCIATED WITH BACK PAIN: MORPHOGENETIC ASPECTS

Degeneration of the intervertebral disk (IVD) is a pathological process resulting from an interplay between genetic and environmental factors causing structural and functional damage of the IVD and neighboring structures. It is the first stage of degenerative cascade in the vertebral motion segment. Initiation and progression of IVD degenerative processes traditionally involves several factors: inadequate mechanical load, decreased diffusion of nutrients through the arch laminae, and genetic factors playing a significant role in the development of degenerative changes. Three categories of candidate genes whose coding variants are associated with different forms of degenerative changes in the IVD are identified, a conceptual model of genetic interactions in degenerative disease of the disk is developed. The study of the role of structural changes in back pain genesis, evaluation of risk factors allow to optimize the tactics of patient care and find new therapeutic solutions preventing disease progression.

Parameters and functional analysis of the deep epaxial muscles in the thoracic, lumbar and sacral regions of the equine spine.

The epaxial muscles produce intervertebral rotation in the transverse, vertical and axial axes. These muscles also counteract the movements induced by gravitational and inertial forces and movements produced by antagonistic muscles and the intrinsic muscles of the pelvic limb. Their fascicles are innervated by the dorsal branch of the spinal nerve, which corresponds to the metamere of its cranial insertion in the spinous process. The structure allows the function of the muscles to be predicted: those with long and parallel fibres have a shortening function, whereas the muscles with short and oblique fibres have an antigravity action. In the horse, the multifidus muscle of the thoracolumbar region extends in multiple segments of two to eight vertebral motion segments (VMS). Functionally, the multifidus muscle is considered a spine stabiliser, maintaining VMS neutrality during spine rotations. However, there is evidence of the structural and functional heterogeneity of the equine thoracolumbar multifidus muscle, depending on the VMS considered, related to the complex control of the required neuromuscular activity. Osteoarticular lesions of the spine have been directly related to asymmetries of the multifidus muscle. The lateral (LDSM) and medial (MDSM) dorsal sacrocaudal muscles may be included in the multifidus complex, the function of which is also unclear in the lumbosacral region. The functional parameters of maximum force (Fmax ), maximum velocity of contraction (Vmax ) and joint moment (M) of the multifidus muscles inserted in the 4th, 9th, 12th and 17th thoracic and 3rd and 4th lumbar vertebrae of six horses were studied postmortem (for example: 4MT4 indicates the multifidus muscle that crosses fourmetameres with cranial insertion in the T4 vertebra). Furthermore, the structural and functional characteristics of LDSM and MDSM were determined. Data were analysed by analysis of variance (anova) in a randomised complete block design (P≤0.05). For some muscles, the ordering of Vmax values was almost opposite to that of Fmax values, generally indicating antigravity or dynamic functions, depending on the muscle and VMS. The muscles 3MT12, 3ML3 and 4ML4 exhibited high Fmax and low Vmax values, indicating a stabilising action. The very long 7MT4 and 8MT4 multifidus had low Fmax and high Vmax values, suggesting a shortening action. However, some functional characteristics of interest did not fall within these general observations, also indicating a dual action. In summary, the results of the analysis of various structural and functional parameters confirm the structural and functional heterogeneity of the equine thoracolumbar multifidus complex, depending on the VMS, regardless of the number of metameres crossing each fascicle. To clarify the functions of the equine multifidus muscle complex, this study aimed to assess its functional parameters in thoracolumbar VMSs with different movement characteristics and in the MDSM and LDSM muscles, hypothesising that the functional parameters vary significantly when the VMS is considered.

The role of extracorporeal shock wave therapy in the combined restorative treatment of the patients presenting with myofascial pain syndrome

The myofascial pain syndromes (MPS) is ranked among the most frequent clinical manifestations of acute and chronic pain in the lumbar region. The authors of the article undertook the analysis of scientific publications from the Pubmed, Medline, and Scopus databases that appeared during the recent years. The analysis has demonstrate that extracorporeal shock wave therapy (ESWT) can be considered as a method of choice to be used in the framework of the complex programs of the treatment and rehabilitation of the condition of interest. The specific etiopathogenetic features of ESWT are considered in terms of the contemporary views with special reference to their influence on the choice of the treatment strategies and concrete methods for the treatment of the myofascial pain syndromes. It is shown that extracorporeal shock wave therapy makes it possible to enhance the blood flow and circulation and increase the permeability of cell membranes thereby facilitating the activation of the regenerative processes in the structural elements of the vertebral-motor segment undergoing the dystrophic changes. Moreover, ESWT produces the anti-inflammatory effects and causes muscle relaxation. There is strong evidence of the possibility to use such modern modalities of manual needs tlomethods of ESWT and manual therapy in patients with MFBS that requires further research. The expected effects of the combined application of extracorporeal shock wave therapy and manual therapy for the treatment of the patients presenting with myofascial pain syndrome remain to be verified in the further studies.

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Purpose Our goal is to demonstrate a typical clinical situation that promotes the development of PJF and PJK, as well as a variant of surgical treatment of these complications. Material and methods A case of a fracture of the overlying vertebra above the level of metal fixation of the vertebra and development of proximal junctional kyphosis (PJF and PJK) in a patient operated for degenerative scoliosis of the lumbar spine. Repeated extended stabilization of the spine without cranial level protection resulted in the re-development of this complication. Vertebroplasty of the bodies of two vertebrae cranial from the fixed vertebral motor segment was performed in order to prevent the development of PJF and PJK and a hybrid fixation with a polymeric band on the cranial vertebral motor segment (VMS) was performed. Result Observation for a year confirms a good result of treatment. Conclusion Using vertebroplasty of two vertebrae cranial from the fixed vertebral motor segment with 7-8 ml of bone cement per vertebra prevented the possible development of PJF and PJK in the presented clinical observation and achieved a good clinical outcome. Laminar band fixation of the cranial VMS ensured the transition of the rigid system into a semi-rigid system in its proximal part, which also contributed to prevention of PJF and PJK.

The segment-dependent changes in lumbar intervertebral space height during flexion-extension motion.

ObjectivesMany studies have investigated the kinematics of the lumbar spine and the morphological features of the lumbar discs. However, the segment-dependent immediate changes of the lumbar intervertebral space height during flexion-extension motion are still unclear. This study examined the changes of intervertebral space height during flexion-extension motion of lumbar specimens.MethodsFirst, we validated the accuracy and repeatability of a custom-made mechanical loading equipment set-up. Eight lumbar specimens underwent CT scanning in flexion, neural, and extension positions by using the equipment set-up. The changes in the disc height and distance between adjacent two pedicle screw entry points (DASEP) of the posterior approach at different lumbar levels (L3/4, L4/5 and L5/S1) were examined on three-dimensional lumbar models, which were reconstructed from the CT images.ResultsAll the vertebral motion segments (L3/4, L4/5 and L5/S1) had greater changes in disc height and DASEP from neutral to flexion than from neutral to extension. The change in anterior disc height gradually increased from upper to lower levels, from neutral to flexion. The changes in anterior and posterior disc heights were similar at the L4/5 level from neutral to extension, but the changes in anterior disc height were significantly greater than those in posterior disc height at the L3/4 and L5/S1 levels, from neutral to extension.ConclusionsThe lumbar motion segment showed level-specific changes in disc height and DASEP. The data may be helpful in understanding the physiologic dynamic characteristics of the lumbar spine and in optimising the parameters of lumbar surgical instruments.Cite this article: M. Fu, Q. Ye, C. Jiang, L. Qian, D. Xu, Y. Wang, P. Sun, J. Ouyang. The segment-dependent changes in lumbar intervertebral space height during flexion-extension motion. Bone Joint Res 2017;6:245–252. DOI: 10.1302/2046-3758.64.BJR-2016-0245.R1.

Ultrasonography of the Diagnosis the Degenerative-Dystrophic Changes in the Vertebral Motor Segment as a Potential Cause of Back Pain: Pictorial Essay

The topical diagnosis and determination of the mechanism of pain of vertebrogenic origin remain the actual problems of medicine. This is due to the difficulty in differential diagnosis, the high incidence of occurrence, the severity of clinical manifestations of the spinal column pathology and their consequences, and the anatomical features of the structure of the vertebrae. From the clinical point of view, the solution to the problem of vertebrogenic pain involves a number of aspects: The definition of the source of pain, the establishment of its mechanisms and paths for its elimination. Thus, ultrasonography is effective for the diagnosis the degenerative-dystrophic changes in the vertebral motor segment as a potential cause for pathophysiological mechanism of back pain.

Biomechanical Analysis of Intervertebral Cement Extravasation in Vertebral Motion Segments.

Kyphoplasty is a therapeutic option for pain relief in the setting of compression fractures. Cement extravasation into adjacent disks is a common occurrence. The biomechanical and clinical consequences of cement in the disks currently are unknown. This study investigated the biomechanical effects of cement extravasation into the intervertebral disk in a human cadaveric model. Seven thoracolumbar and lumbar embalmed human cadaveric motion segments were evaluated in axial rotation, right and left lateral bending, and flexion and extension. Stiffness was calculated at baseline and following injection of 1 mL of cement into the intervertebral disk. There was a 13.4% (P=.041) increase in stiffness in axial rotation compared with preinjection motion segments. No significant difference was observed in lateral bending or flexion and extension. In this model, cement extravasation into the disk space increased stiffness in axial rotation. [Orthopedics. 2017; 40(2):e300-e304.].

Structural and functional characteristics of the thoracolumbar multifidus muscle in horses.

The multifidus muscle fascicles of horses attach to vertebral spinous processes after crossing between one to six metameres. The fascicles within one or two metameres are difficult to distinguish in horses. A vertebral motion segment is anatomically formed by two adjacent vertebrae and the interposed soft tissue structures, and excessive mobility of a vertebral motion segment frequently causes osteoarthropathies in sport horses. The importance of the equine multifidus muscle as a vertebral motion segment stabilizer has been demonstrated; however, there is scant documentation of the structure and function of this muscle. By studying six sport horses postmortem, the normalized muscle fibre lengths of the the multifidus muscle attached to the thoracic (T)4, T9, T12, T17 and lumbar (L)3 vertebral motion segments were determined and the relative areas occupied by fibre types I, IIA and IIX were measured in the same muscles after immunohistochemical typying. The values for the normalized muscle fibre lengths and the relative areas were analysed as completely randomized blocks using an anova (P≤0.05). The vertebral motion segments of the T4 vertebra include multifidus bundles extending between two and eight metameres; the vertebral motion segments of the T9, T12, T17 and L3 vertebrae contain fascicles extending between two and four metameres The muscle fibres with high normalized lengths that insert into the T4 (three and eight metameres) vertebral motion segment tend to have smaller physiological cross-sectional areas, indicating their diminished capacity to generate isometric force. In contrast, the significantly decreased normalized muscle fibre lengths and the increased physiological cross-sectional areas of the fascicles of three metameres with insertions on T9, T17, T12, L3 and the fascicles of four metameres with insertions on L3 increase their capacities to generate isometric muscle force and neutralize excessive movements of the vertebral segments with great mobility. There were no significant differences in the values of relative areas occupied by fibre types I, IIA and IIX. In considering the relative areas occupied by the fibre types in the multifidus muscle fascicles attached to each vertebral motion segment examined, the relative area occupied by the type I fibres was found to be significantly higher in the T4 vertebral motion segment than in the other segments. It can be concluded that the equine multifidus muscle in horses is an immunohistochemically homogeneous muscle with various architectural designs that have functional significance according to the vertebral motion segments considered. The results obtained in this study can serve as a basis for future research aimed at understanding the posture and dynamics of the equine spine.

Regeneration of intervertebral disc by way using of allogeneic chondrocytes cultivated in vitro in the light of concept for restabilization of the spine(experimental investigation)

The intervertebral disc (ID) has low reparative capacity. In this regard, researcher aimed at improving the capacity of the re­parative structures are carried out. A variety of growth factors, mesenchymal stem cells, autologous and allogenic chondrocytes, etc are used for this purposes. Objective: to study the structure of the traumatized intervertebral disc after transplantation of allogenic chondroсуtes in combination with spinal restabiliza­tion using method of dynamic spine neutralization of vertebral motion unit (VMU). Methods for optimizing ID regeneration in the rat tail vertebral segment we selected high-density culture of chondrocytes obtained from the limb bud 7–10 day old rat embryos in which cells retain cartilaginous phenotype and gen­otype was confirmed by electron microscopy. Performed four se­ries of experiments: I — intact animals, II — ID injury (control), III — traumatic ID injury with dynamic neutralization (method G. Dubois et al, 1999), IV — ID injury with dynamic neutraliza­tion and transplantation of chondrocytes. One month the opera­tion the animals were euthanized, and a comparative morpho­logical analysis with morphometry was carried out. Results: it found that uncontrolled movements in the injured VMU lead to destructive changes in the ID. In terms of restabilization and dy­namic neutralization of the vertebral motor segment ID has been replaced by connective tissue, its height reduced. Chondrocyte culture is different from the fibrous ring and nucleus pulposus cells. However, with the introduction of chondrocytes in the in­jured ID and maintaining the controlled mobility of the VMU the proliferation of hyaline cartilage in its peripheral parts has been noted. Conclusion: combination of allogeneic chondro­cytes transplantation into disk and dynamic neutralization leads to the formation of hyaline cartilage territories and maintains the height of the injured ID.