Towards the First Generation of Biomimetic Fixation for Resurfacing Arthroplasty Endoprostheses.

This paper presents advances in designs of resurfacing arthroplasty endoprostheses that occurred through their historical generations. The critical characteristics of contemporary generation hip resurfacing arthroplasty endoprostheses are given and the failures resulting from the specific generation cemented and short stem fixation of the femoral component are reviewed. On the background of these failures, the critical need arises for an alternative approach to the fixation of components of resurfacing arthroplasty leading towards the first generation of biomimetic fixation for resurfacing arthroplasty endoprostheses. The state of the art of the completed bioengineering research on the first biomimetic fixation for resurfacing arthroplasty endoprostheses is presented. This new design type of completely cementless and stemless resurfacing arthroplasty endoprostheses of the hip joint (and other joints), where endoprosthesis components are embedded in the surrounding bone via the prototype biomimetic multi-spiked connecting scaffold (MSC-Scaffold), initiates the first at all generations of biomimetic endoprostheses of diarthrodial joints.

The Influence of Clinical Factors on Treatment Outcome and a Recurrence of Surgically Removed Protruded Subungual Osteochondroma and Subungual Exostosis.

BACKGROUND: Subungual exostosis (SE) and subungual osteochondroma (SO) are benign solitary lesions that grow from the distal phalanx. The mass itself is typically painless, but pressure on the nail plate can result in pain and deformity of the involved digit. Tumors can be correctly diagnosed based on clinical, histological and radiographic appearance alone. Surgical resection of SE/SO is typically curative, with a small risk of recurrence. METHODS: The study was retrospective and observational, involving 74 patients with subungual SE/SO. The surgical procedure consisted of the removal of the tumor from the dorsal approach under digital anesthesia. The procedure was assessed using a questionnaire and photo documentation after a minimum of 6 months after surgery. RESULTS: A total of 85% of respondents were satisfied with the procedure. Nearly 80% of patients rated the cosmetic effect as good or very good. Young age and pain intensity after surgery showed statistically significant associations with worse satisfaction. Age < 18 was associated with recurrence. CONCLUSIONS: Worse satisfaction is strongly associated with recurrence. Gender, duration of symptoms, pain before surgery and tumor size and destruction of the nail plate had no significant effect on recurrence. The technique using burr appeared to be a more effective treatment.

The Influence of Osteon Orientation on Surface Topography Parameters after Machining of Cortical Bone Tissue.

Mechanical processing of cortical bone tissue is one of the most common surgical procedures. A critical issue accompanying this processing is the condition of the surface layer, which can stimulate tissue growth and serve as a drug carrier. A comparison of the surface condition before and after orthogonal and abrasive processing was conducted to validate the influence of bone tissue's processing mechanism and orthotropic properties on the surface topography. A cutting tool with a defined geometry and a custom-made abrasive tool was used. The bone samples were cut in three directions, depending on the orientation of the osteons. The cutting forces, acoustic emission, and surface topography were measured. The level of isotropy and the topography of the grooves showed statistical differences relative to the anisotropy directions. After orthogonal processing, the surface topography parameter Ra was determined from 1.38 ± 0.17 µm to 2.82 ± 0.32. In the case of abrasive processing, no correlation was found between the orientation of osteons and topographical properties. The average groove density for abrasive machining was below 1004 ± 0.7, and for orthogonal, it was above 1156 ± 58. Due to the positive properties of the developed bone surface, it is advisable to cut in the transverse direction and parallel to the axis of the osteons.

Temporary Occlusion of Common Carotid Arteries Does Not Evoke Total Inhibition in the Activity of Corticospinal Tract Neurons in Experimental Conditions.

Temporary occlusion of the common cervical artery is the reason for ischemic stroke in 25% of patients. Little data is provided on its effects, especially regarding neurophysiological studies verifying the neural efferent transmission within fibers of the corticospinal tract in experimental conditions. Studies were performed on 42 male Wistar rats. In 10 rats, ischemic stroke was evoked by permanent occlusion of the right carotid artery (group A); in 11 rats, by its permanent bilateral occlusion (B); in 10 rats, by unilateral occlusion and releasing after 5 min (C); and in 11 rats, by bilateral occlusion and releasing after 5 min (D). Efferent transmission of the corticospinal tract was verified by motor evoked potential (MEP) recordings from the sciatic nerve after transcranial magnetic stimulation. MEPs amplitude and latency parameters, oral measurements of temperature, and verification of ischemic effects in brain slides stained with hematoxylin and eosin staining (H + E) were analyzed. In all groups of animals, the results showed that five minutes of uni- or bilateral occlusion of the common carotid artery led to alterations in brain blood circulation and evoked changes in MEP amplitude (by 23.2% on average) and latency parameters (by 0.7 ms on average), reflecting the partial inability of tract fibers to transmit neural impulses. These abnormalities were associated with a significant drop in the body temperature by 1.5 °C on average. Ten minutes occlusion in animals from groups A and B resulted in an MEP amplitude decrease by 41.6%, latency increase by 0.9 ms, and temperature decrease by 2.9 °C of the initial value. In animals from groups C and D, five minutes of recovery of arterial blood flow evoked stabilization of the MEP amplitude by 23.4%, latency by 0.5 ms, and temperature by 0.8 °C of the initial value. In histological studies, the results showed that ischemia was most prominent bilaterally in sensory and motor areas, mainly for the forelimb, rather than the hindlimb, innervation of the cortex, putamen and caudate nuclei, globulus pallidus, and areas adjacent to the fornix of the third ventricle. We found that the MEP amplitude parameter is more sensitive than the latency and temperature variability in monitoring the ischemia effects course following common carotid artery infarction, although all parameters are correlated with each other. Temporary five-minute lasting occlusion of common carotid arteries does not evoke total and permanent inhibition in the activity of corticospinal tract neurons in experimental conditions. The symptoms of rat brain infarction are much more optimistic than those described in patients after stroke, and require further comparison with the clinical observations.

The Role of Cytokines in the Metastasis of Solid Tumors to the Spine: Systematic Review.

Although many studies have investigated the role of cytokines in bone metastases, our knowledge of their function in spine metastasis is limited. Therefore, we performed a systematic review to map the available evidence on the involvement of cytokines in spine metastasis in solid tumors. A PubMed search identified 211 articles demonstrating a functional link between cytokines/cytokine receptors and bone metastases, including six articles confirming the role of cytokines/cytokine receptors in spine metastases. A total of 68 cytokines/cytokine receptors were identified to mediate bone metastases; 9 (mostly chemokines) played a role in spine metastases: CXC motif chemokine ligand (CXCL) 5, CXCL12, CXC motif chemokine receptor (CXCR) 4, CXCR6, interleukin (IL) 10 in prostate cancer, CX3C motif chemokine ligand (CX3CL) 1 and CX3C motif chemokine receptor (CX3CR) 1 in liver cancer, CC motif chemokine ligand (CCL) 2 in breast cancer, and transforming growth factor (TGF) ß in skin cancer. Except for CXCR6, all cytokines/cytokine receptors were shown to operate in the spine, with CX3CL1, CX3CR1, IL10, CCL2, CXCL12, and CXCR4 mediating bone marrow colonization, CXCL5 and TGFß promoting tumor cell proliferation, and TGFß additionally driving bone remodeling. The number of cytokines/cytokine receptors confirmed to mediate spinal metastasis is low compared with the vast spectrum of cytokines/cytokine receptors participating in other parts of the skeleton. Therefore, further research is needed, including validation of the role of cytokines mediating metastases to other bones, to precisely address the unmet clinical need associated with spine metastases.

Factors Influencing Treatment Outcome and Proprioception after Electrocoagulation of the Femoral Insertion of the Anterior Cruciate Ligament.

(1) Background: Studies have established that exercises shaping the sense of deep sensation are an important element of medical rehabilitation of patients after vaporization of the femoral insertion of the anterior cruciate ligament and affect the restoration of correct movement patterns, thus reducing the risk of injuries. The aim of this study was to determine the factors influencing the treatment outcome and deep-feeling function after applying a specific rehabilitation scheme 12 weeks after anterior cruciate ligament electrocoagulation surgery. (2) Methods: The study group consisted of 41 patients after partial rupture of the anterior cruciate ligament, who underwent electrocoagulation of the femoral cruciate ligament attachment and microfracture of the femoral attachment area. All patients were operated on by the same surgeon and then rehabilitated according to the same medical rehabilitation protocol. The anthropometric and clinical data were collected through an anterior drawer test, Lachman test, assessment of the range of movements in the knee joint, muscle strength test, Unterberger test and Lysholm questionnaire. The assessment was performed before the surgery, and then on days 7-10, after 6 and 12 weeks of rehabilitation treatment. (3) Results: Statistical improvement of the parameters was demonstrated by strength of the quadriceps and hamstrings muscle, the Unterberger test, and the Lysholm scale after surgery. A negative correlation was found between the Unterberger test and Lysholm scale at the end of the research period and it differed depending on the gender and the dominant limb. The Lysholm scale and muscle strength were independent of sex, dominant extremity and associated damage of the meniscus and cartilage. The Lysholm scale 6 weeks after surgery negatively correlated with BMI. (4) Conclusions: Stability of the knee joint and improvement of proprioception were demonstrated 12 weeks after treatment with an ACL electrocoagulation and rehabilitation regimen. The factors contributing to a better treatment outcome were greater muscle strength, less thigh asymmetry, better sense of depth, younger age and lower body weight.

Sex- and Age-Related Dynamic Changes of the Macroelements Content in the Femoral Bone with Hip Osteoarthritis.

BACKGROUND: The content of macroelements in bones varies with age and depends on sex. The aim of the study was to evaluate the content of macroelements and its correlation with age and sex in the femoral bone obtained during total hip arthroplasty. METHODS: In the 86 patients, the content of macroelements (Ca, P, Mg, and Na) in the femoral head and neck (cancellous and cortical bone) was assessed by means of the inductively coupled plasma optical emission spectrometry analytical technique (ICP-OES). RESULTS: There was a decrease in the content of macroelements in the cortical bone with age in the women in the 51-60 years (statistically significant: -0.59 for Ca, -0.65 for P) and over 70 years age groups (correlation not statistically significant: -0.29 for Ca, -0.38 for P). A significant decrease in the content of macroelements in the cortical bone was found in men over 70 years of age. CONCLUSIONS: Patterns of increased loss of macronutrients (Ca, P, and Mg) in the femoral neck (cortical bone) were demonstrated in the following patients with osteoarthritis: women aged 51-60 years and patients of both sexes over 70 years of age.

Impact of Selected Behavioral and Environmental Factors on the Antibiotic Therapy in Polish Children With Upper Respiratory Tract Infections.

Antibiotic therapy must be carried out consistently and according to the guidelines. Viruses are the dominant cause of upper respiratory tract infections (URTIs) in children, as has been shown in many previous studies. Unnecessary antibiotic therapy should be avoided so that it does not affect patients' health and lead to the development of resistant bacterial strains. Here we report a national survey conducted in a group of 4,389 children to assess the impact of selected behavioral and environmental factors on antibiotic therapy in patients with URTIs. We found that selected environmental factors influenced the type of treatment. The place of residence, having siblings, an absence of vaccinations, the presence of allergies, and attendance at educational institutions were conducive to antibiotic therapy. These factors also influenced the frequency of hospitalization of children and their absence from nurseries, kindergartens, and schools, as well as the absence of their guardians from work.

Avascular Necrosis Bone Complication after Active COVID-19 Infection: Preliminary Results.

Background and objectives: The course of SARS-CoV-2 (COVID-19) is still under analysis. The majority of complications arising from the infection are related to the respiratory system. The adverse effect of the viral infection on bone and joint tissue has also been observed. Materials and Methods: We present a group of 10 patients with degeneration of large joints and adjacent epiphyses of long bones and the spine, with a background of bone infarctions and avascular necrosis (AVN) immediately after infection with the COVID-19 virus. In MR imaging, changes in the characteristics of AVN were documented. Results: Observation of this group showed a clear correlation among the history of COVID-19 disease in the patients, moderately severe symptoms, high levels of IgG antibodies, and the time of occurrence of joint changes. No other clinically significant complications were observed following COVID-19 infection in the study group. No other risk factors for AVN or autoimmune or degenerative diseases were found in the study group. The group of patients responded well to empirical treatment with steroids, which normalized acute inflammatory symptoms and pain in the joints. Conclusions: During coronavirus (COVID-19) infection, there are complications in the locomotor system, such as microembolism and the formation of AVN; hence, more research is needed.

Impact of the oxidative and enzymatic metals in degenerated intervertebral disc disease.

INTRODUCTION: The degenerative process of the intervertebral disc is a heterogeneous process that may exist in two forms, and involves dominant degenerative changes within the nucleus pulposus and the annulus fibrosus. In degenerative disc disease, the oxidative stress factor can play an important role. OBJECTIVE: The aim of research was to present a new approach to understanding the role of the analyzed elements in the process of degeneration of the intervertebral disc. MATERIAL AND METHODS: Selected elements from oxidative groups (Fe, Zn, Mo, As, Se), associated with enzymatic processes (Fe, Mo, Se, Zn, Ag, As, Bi), metals (Fe, Zn, Mo, Li) and metalloids (As, Bi) and their content was analyzed depending on the changes in the radiological images of the intervertebral disc. Elemental content analysis was performed by Inductively Coupled Plasma Mass Spectrometry analytical technique. RESULTS: The similarity between Fe and Se has been demonstrated during different stages of the analysis of groups of patients with degenerative disc disease. There was a negative correlation between Li and degenerative disc disease. The results also suggest that Fe and Ag are involved in degenerative changes within the intervertebral disc. A potential relationship between As/Bi and Fe/Mo in the degeneration of the intervertebral disc was demonstrated. CONCLUSIONS: Only some of the correlations can be explained by the metabolism of morphological elements of the intervertebral disc. The relationships indicate new directions for further studies on the degeneration process of the intervertebral disc. The presented study may reflect metabolic changes in the intervertebral disc and adjacent structures in response to the progressive degenerative process.

Subchondral Bone Relative Area and Density in Human Osteoarthritic Femoral Heads Assessed with Micro-CT before and after Mechanical Embedding of the Innovative Multi-Spiked Connecting Scaffold for Resurfacing THA Endoprostheses: A Pilot Study.

The multi-spiked connecting scaffold (MSC-Scaffold) prototype is the essential innovation in the fixation of components of resurfacing total hip arthroplasty (THRA) endoprostheses in the subchondral trabecular bone. We conducted the computed micro-tomography (micro-CT) assessment of the subchondral trabecular bone microarchitecture before and after the MSC-Scaffold embedding in femoral heads removed during long-stem endoprosthesis total hip arthroplasty (THA) of different bone densities from 4 patients with hip osteoarthritis (OA). The embedding of the MSC-Scaffold in subchondral trabecular bone causes the change in its relative area (BA/TA, bone area/total area ratio) ranged from 18.2% to 24.7% (translating to the calculated density ρB relative change 11.1-14.4%, and the compressive strength S relative change 75.3-122.7%) regardless of its initial density (before the MSC-Scaffold embedding). The densification of the trabecular microarchitecture of subchondral trabecular bone due to the MSC-Scaffold initial embedding gradually decreases with the increasing distance from the apexes of the MSC-Scaffold's spikes while the spatial extent of this subchondral trabecular bone densification ranged from 1.5 to 2.5 mm (which is about half the height of the MSC-Scaffold's spikes). It may be suggested, despite the limited number of examined femoral heads, that: (1) the magnitude of the effect of the MSC-Scaffold embedding on subchondral trabecular bone densification may be a factor contributing to the maintenance of the MSC-Scaffold also for decreased initial bone density values, (2) the deeper this effect of the subchondral trabecular bone densification, the better strength of subchondral trabecular bone, and as consequence, the better post-operative embedding of the MSC-Scaffold in the bone should be expected.

Comparison of Bone Tissue Trace Element Content in the Different Radiological Stages of Hip Osteoarthritis.

Bone metabolism and the trace element content associated with it change at each stage of degenerative disease. The aim of this study was to find out about the role of the analyzed elements in different stages of hip osteoarthritis. Elements associated with oxidative and enzymatic processes were analyzed depending on the changes in the radiological images of the hip joint. Element content analysis was performed by the inductively coupled plasma mass spectrometry analytical technique. The femoral head in severely osteoarthritic hips (KL3-4) compared to mild grade osteoarthritis (KL2) had a greater content of Cu (median 1.04 vs. 0.04), Sr (median 38.71 vs. 29.59), and Zn (median 75.12 vs. 63.21). There were no significant differences in the content of Mo, Cr, and Fe in the femoral head and neck between the groups. The Cu/Fe correlation was negative in the KL2 group (-0.47) and positive in the KL3-4 groups (0.45). Changes in the content and correlation of trace elements in the hip joint explain the changes in metabolism dependent on the severity of degenerative changes.

Diffuse Idiopathic Skeletal Hyperostosis of Cervical Spine with Dysphagia-Molecular and Clinical Aspects.

Diffuse idiopathic skeletal hyperostosis (DISH) is a condition characterized by the calcification and ossification of the ligaments of the cervical spine; in some cases, it may result in dysphagia. The condition is more common in men over 50 years of age with metabolic disorders, and it is often asymptomatic and not a major issue for patients. The etiology of DISH is poorly understood, and known genetic factors indicate multiple signal pathways and multigene inheritance. In this review, we discuss the epidemiological, clinical, and etiological aspects of DISH with a special focus on dysphagia.

Efficacy of a tip of the big toe remodeling in the distal nail embedding with bone overgrowth of the distal phalanx.

INTRODUCTION: Distal nail embedding due to hyponychium hypertrophy can be caused by traumatic or surgical avulsion of the nail. As a consequence of these changes, the nail plate is blocked through the deformed tip of the toe. Changes that occur at the tip of the big toe are due to bone growth on the dorsal surface of the distal end of the distal phalanx. This study aimed to present a surgical technique for the treatment of hypertrophy of the tip of the toe and evaluate its effectiveness. MATERIAL AND METHODS: The surgical technique involved remodeling of the tip of the big toe, with removal of the hypertrophied bone of the distal phalanx. The procedure was assessed by using a questionnaire. RESULTS: We included the 108 distal embedded nails. A total of 85% of respondents were satisfied with the procedure. Nearly 80% of patients rated the cosmetic effect as good or very good. CONCLUSIONS: The technique was an effective treatment and increased the quality of life of those with disorders of nail growth associated with hypertrophy of the tip and hyponychium, with bone overgrowth.

Surgical treatment of diffuse idiopathic skeletal hyperostosis of cervical spine with dysphagia - Case report.

INTRODUCTION: Diffuse idiopathic skeletal hyperostosis of cervical spine can lead to dysphagia. PRESENTATION OF CASE: A 73-year-old male weighing 110 kg and diagnosed with diffuse idiopathic skeletal hyperostosis in cervical spine with dysphagia. Patient manifested local pain of neck, a gradual limitation of spinal mobility. The surgery decision was based on swallowing problems, not pain in the spine. Before surgery radiographs, magnetic resonance images, computed tomography of the cervical spine and gastroscopy were obtained. Osteophytes were removed from the anterior approach with present otolaryngologist by surgery. DISCUSSION: In this case used gastroscopy, CT and MRI for diagnostics. During the procedure we had support otolaryngologist. The patient has not been found a stenosis spinal canal and neurological symptoms. We were removed the ostheophytes. Interbody implants have not been applied. CONCLUSION: Disc degeneration disease itself can be asymptomatic or not a dominant problem for the DISH patients. Clinical signs may pharyngoesophageal and tracheal compression, causing dysphagia, shortness of breath and stridor. In this case, the cervical spine was stability and not demonstrated a stenosis in the spinal canal. Isolate removing of the osteophytes without implants in DISH of cervical spine can be enough solution.

Recurrence and satisfaction with sutured surgical treatment of an ingrown toenail.

BACKGROUND: In the present study, we investigated the satisfaction of patients following sutured surgical treatment of an ingrown toenail with nail preservation and without matricectomy. MATERIALS AND METHODS: This study was retrospective. In total, 37 consecutive patients underwent 54 ingrown toenail surgeries. The clinical outcomes, satisfaction of surgery, recurrence rates and the duration of symptoms were compared. RESULTS: Recurrence with the technique was very low (one toenail). The mean overall satisfaction score on the surgical satisfaction questionnaire was 86.4 ± 10.4 and extended with a modified esthetic subscale (88 ± 10). The mean pain subscale score was the lowest at 77.1 ± 16.8, while the subscale returns to baseline scored 80.9 ± 16.4, the subscale global satisfaction scored 98.1 ± 7.2 and the subscale esthetics scored 92.1 ± 15. CONCLUSION: Our suturing technique was associated with low recurrence and high satisfaction rates. We showed that higher levels of satisfaction with the treatment were achieved in men, and the duration of symptoms was no longer than one year.

First Biomimetic Fixation for Resurfacing Arthroplasty: Investigation in Swine of a Prototype Partial Knee Endoprosthesis.

Resurfacing hip and knee endoprostheses are generally embedded in shallow, prepared areas in the bone and secured with cement. Massive cement penetration into periarticular bone, although it provides sufficient primary fixation, leads to the progressive weakening of peri-implant bone and results in failures. The aim of this paper was to investigate in an animal model the first biomimetic fixation of components of resurfacing arthroplasty endoprostheses by means of the innovative multispiked connecting scaffold (MSC-Scaffold). The partial resurfacing knee arthroplasty (RKA) endoprosthesis working prototype with the MSC-Scaffold was designed for biomimetic fixation investigations using reverse engineering methods and manufactured by selective laser melting. After Ca-P surface modification of bone contacting surfaces of the MSC-Scaffold, the working prototypes were implanted in 10 swines. Radiological, histopathological, and micro-CT examinations were performed on retrieved bone-implant specimens. Clinical examination confirmed very good stability (4 in 5-point Likert scale) of the operated knee joints. Radiological examinations showed good implant fixation (radiolucency less than 2 mm) without any signs of migration. Spaces between the MSC-Scaffold spikes were penetrated by bone tissue. The histological sections showed newly formed trabecular bone tissue between the spikes, and the trabeculae of periscaffold bone were seen in contact with the spikes. The micro-CT results showed the highest percentage of bone tissue ingrowths into the MSC-Scaffold at a distance of 2.5÷3.0 mm from the spikes bases. The first biomimetic fixation for resurfacing arthroplasty was successfully verified in 10 swines investigations using RKA endoprosthesis working prototypes. The performed research shows that the MSC-Scaffold allows for cementless and biomimetic fixation of resurfacing endoprosthesis components in periarticular cancellous bone.

Urban and rural area differences in the interaction between oxidative process elements in human femoral bone.

Elements in the human body come from contaminated food, water, and air from the living area. Bones are a marker of long-term exposure to elements and show a relationship between them. The aim of the study was to analyze the correlation between the contents of Zn, Cu, Fe, Mo, Cr, Ni, Ba, Sr, and Pb in the proximal femoral head (cancellous bone) and femoral neck (cortical bone) in rural and urban populations. The study included 96 patients who were operated on for total hip replacement (THR), acquired in a surgical procedure with atomic absorption spectrometry, and the content of Zn, Cu, Fe, Mo, Cr, Ni, Ba, Sr, and Pb was evaluated. In rural areas, significant negative correlations were observed for Mo/Cr, Mo/Cu, and Ni/Fe, and positive correlations were observed for Fe/Zn and Pb/Zn. In urban areas, a negative correlation was found for Pb/Mo. Pb and Ni increased with age only in villagers, and Zn and Sr decreased with age in urban citizens. Ba decreased with age in people from rural areas. The correlation showed variances mainly in molybdenum, nickel, and oxidative elements between rural and urban populations.

Chemometric evaluation of concentrations of trace elements in intervertebral disc tissue in patient with degenerative disc disease.

BACKGROUND: The work is designed to uncover the pattern of mutual relation among trace elements and epidemiological data in the degenerated intervertebral disk tissue in humans. Hitherto the reason of the degenerative process is not fully understood. Trace elements are the basic components of the biological compound related both its metabolism as well as environmental exposure. The relation pattern among elements occurs gives new perspective in solving the cause of the disease. MATERIAL AND METHODS: We have analysed trace elements content in the 30 intervertebral disc from 22 patients with degenerative disc disease. The concentrations of Al, Cu, Cd, Mo, Ni and Pb were determined with Atomic Absorption Spectrometry. To analyse the multidimentional relation between trace element concentration and epidemiological data the chemometric analysis was applied. RESULTS: The similarity have been shown in occurrence of following pairs: Cd-Mo as well as Mg-Zn. The second pair was correlated with Pb concentration. Pb levels are observed to be competitive to Cu concentration. Cd concentration was related to Zn and Mg deficiency. No single but rather cluster of epidemiological data show observable influence on the TE tissue variance. Zn and Cu was related to the male sex. Operation with orthopedic implants were related to combined Al, Mo and Zn concentration. CONCLUSIONS: This is the first chemometric analysis of trace elements in disk tissue. It shows multidimentional relations that are missed by the classical statistic. The analysis shows significant relation. The nature of the relations is the basis for further metabolic and environmental research.

Interrelationship between silicon, aluminum, and elements associated with tissue metabolism and degenerative processes in degenerated human intervertebral disc tissue.

There is a growing body of evidence concerning the significant role of silicon in development and composition of both connective and bone tissue. Bio-essential silicon shows strong chemical and biological affinity to aluminum, which is toxic and biologically inessential element. The presence of silicon was confirmed in a variety of tissues; however, it has never been examined in intervertebral disc tissue, neither in healthy nor in degenerated one. In this paper, for the first time in the literature, we present the content of silicon in the degenerated intervertebral disc tissue. We also compared the results of silicon analysis with aluminum values in degenerated intervertebral disc tissue in humans. We used chemometric methods to find correlations and similarities between silicon, aluminum, and elements associated with tissue metabolism (Mg) and degenerative processes (Zn and Cu). The presence of silicon was confirmed in all 30 samples harvested from 22 patients operated on due to degenerative changes. Its concentration was within the range of 5.37-12.8 µg g-1 d.w., with the mean concentration of 7.82 µg g-1 d.w. The analysis showed significant correlation between Si and both Al and Mg and weak or negative correlation with Zn and Cu, where the latter was probably the result of degenerative processes. Although silicon is considered essential in glycosaminoglycan and collagen synthesis in connective tissue, it did not show any correlation nor similarities with elements reflecting changes associated with the degenerative process of the intervertebral disc. Silicon showed significant correlation with aluminum, similar to those observed in other human tissues.