short-stem
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PURPOSE OF THE STUDY: The aim of the study was to evaluate the clinical and radiographic results of total hip arthroplasty (THA) with the Metha short hip stem and their comparison with the outcomes of THA using a conventional cementless stem. MATERIAL AND METHODS: A total of 30 Metha stems and 30 standard Biocontact stems implanted in the period from 2007 to 2012 were evaluated. The Metha patient group comprised 22 women and six men, with the mean age of 58.9 ± SD 8.7 years (43-75), mean height of 164.2 ± 6.3 cm (156-178), mean body mass of 68.2 ± 12 (48-91) and mean BMI of 25 ± 3.9 (19-32). The Biocontact group included 19 women and 11 men, with the mean age of 63.6 ± 10.8 years (45-77), mean height of 166.6 ± 6.6 cm (152-175), mean body mass of 77.6 ± 13.1 (46-104) and mean BMI of 27.6 ± 4.3 (20-37). The evaluation was based on plain X-ray findings and clinical status assessed using the Harris hip score and 10-point visual analogue scale (VAS) for pain before surgery and at final follow-up. RESULTS: In the Metha group the mean pre- and post-operative Harris hip scores were 41.7 ± 9.9 (28-57) and 94.4 ± 5.1 (82-100), respectively. In the Biocontact group the values were 41.5 ± 11.9 (32-64) and 89.3 ± 11.2 (57-100), respectively. The mean VAS for low back and thigh pain improved from the pre-operative value of 7.41 ± 2.1 (4-9) to 0.56 ± 1.0 (0-3) in the Metha group and from 7.29 ± 2.2 (4-9) to 1.64 ± 1.8 (0-5) in the Biocontact group. The post-operative results in both rating systems were significantly better (p<0.05) in the Metha than the Biocontact group patients. All stems showed radiographic evidence of good osteointegration. Stem subsidence and calcar atrophy were recorded in one patient of the Metha group. In the Biocontact group stem subsidence was found in two patients and signs of stress shielding in 14 patients. DISCUSSION: Short hip stems have been introduced in THA implantation with the aim to restore physiological biomechanics as much as possible and to ensure good long-term functioning of the joint replacement as well as to save the proximal femoral bone tissue for potential THA re-implantation. Our results of short hip stem implantation presented in this study are compared with the results of relevant recently published literature. CONCLUSIONS: Short hip stems show adequate osteointegration without need for diaphyseal fixation and allow for more natural weightbearing distribution in the proximal femur. The short- and mid-term clinical results are better than with the use of conventional cementless stems. They can be recommended as an optimal choice for use in younger patients with good bone quality who are expected to require THA re-implantation.
- MeSH
- kyčelní kloub * radiografie chirurgie MeSH
- kyčelní protézy klasifikace MeSH
- lidé středního věku MeSH
- lidé MeSH
- náhrada kyčelního kloubu * škodlivé účinky přístrojové vybavení metody MeSH
- pooperační období MeSH
- protézy - design * MeSH
- selhání protézy MeSH
- senioři MeSH
- srovnávací výzkum účinnosti MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- srovnávací studie MeSH
- MeSH
- implantace protézy metody MeSH
- kyčelní kloub chirurgie MeSH
- kyčelní protézy využití MeSH
- lidé středního věku MeSH
- lidé MeSH
- longitudinální studie MeSH
- náhrada kyčelního kloubu metody MeSH
- statistika jako téma MeSH
- výsledek terapie MeSH
- výsledky a postupy - zhodnocení (zdravotní péče) MeSH
- výzkum statistika a číselné údaje MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
BACKGROUND: Mid-term results (clinical and radiographic) of ultra-short anatomical cementless stem total hip arthroplasty (THA) in patients with osteonecrosis of the femoral head (ONFH) has not often been presented. The aim of this study is to evaluate THA using the Proxima stem in patients with ONFH in the mid-term. METHODS: The study consists of 73 patients (97 THAs) with a Proxima stem implanted between 2006 and 2015. The mean age of patients was 47.4 years, with a mean follow-up 105.2 months. The clinical results include preoperative and postoperative Harris Hip Scores (HHSs). Radiological follow-up reports on stem migration, bony trabecular development and radiolucent lines. The complications and revisions were registered. Kaplan-Meier survival analysis was performed to determine the implant survival. RESULTS: The average HHS improved significantly from 40.3 preoperatively to 98.0 at the final evaluation (p ˂ 0.0001). Stem migration (subsidence and "varisation") was observed in 11 hips (in 9 of them up to 6th postoperative month without any further progression, in 2 with progressive migration and radiological loosening). Bony trabecular development was detected in modified Gruen zones (1,2,4,6,7 for Proxima stem): in zone 1 (0%), 2 (67.0%), 4 (64.9%), 6 (64.9%), 7 (0%). Radiolucent lines were observed in 1 cup and 6 stems (2 were loose, 4 with fibrous stable fixation). Complications were found in 5 hips (5.1%): squeezing hip once, repeated dislocation in 1, 1 early deep infection, and 2 loose stems. 2 hips (2.1%) were revised (dislocation, infection). The implant survival was 98.9% and 97.9% clinically and radiologically, respectively. CONCLUSIONS: Observations in the mid-term show that the clinical and radiological results of the Proxima stem in patients with ONFH are promising. The stem design preserves the proximal femoral bone stock. The bony trabecular appearance confirms physiological proximal femoral load transmission.
- MeSH
- hlavice femuru chirurgie MeSH
- kyčelní protézy * MeSH
- lidé středního věku MeSH
- lidé MeSH
- náhrada kyčelního kloubu * škodlivé účinky metody MeSH
- následné studie MeSH
- nekróza hlavice femuru * diagnostické zobrazování chirurgie MeSH
- protézy - design MeSH
- výsledek terapie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
This study continues our earlier findings on the hematopoiesis-modulating effects of adenosine A1 and A3 receptor agonists that were performed on committed hematopoietic progenitor and precursor cell populations. In the earlier experiments, N (6)-cyclopentyladenosine (CPA), an adenosine A1 receptor agonist, was found to inhibit proliferation in the above-mentioned hematopoietic cell systems, whereas N (6)-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA), an adenosine A3 receptor agonist, was found to stimulate it. The topic of this study was to evaluate the possibility that the above-mentioned adenosine receptor agonists modulate the behavior of early hematopoietic progenitor cells and hematopoietic stem cells. Flow cytometric analysis of hematopoietic stem cells in mice was employed, as well as a functional test of hematopoietic stem and progenitor cells (HSPCs). These techniques enabled us to study the effect of the agonists on both short-term repopulating ability and long-term repopulating ability, representing multipotent progenitors and hematopoietic stem cells, respectively. In a series of studies, we did not find any significant effect of adenosine agonists on HSPCs in terms of their numbers, proliferation, or functional activity. Thus, it can be concluded that CPA and IB-MECA do not significantly influence the primitive hematopoietic stem and progenitor cell pool and that the hematopoiesis-modulating action of these adenosine receptor agonists is restricted to more mature compartments of hematopoietic progenitor and precursor cells.
- MeSH
- agonisté purinergních receptorů P1 farmakologie MeSH
- hematopoetické kmenové buňky účinky léků fyziologie MeSH
- hematopoéza účinky léků fyziologie MeSH
- multipotentní kmenové buňky účinky léků fyziologie MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- průtoková cytometrie MeSH
- receptor adenosinový A1 metabolismus MeSH
- receptor adenosinový A3 metabolismus MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
PURPOSE OF THE STUDY The aim of this study is to assess the mid-term results of this specific ultra-short, cementless stem in patients younger than 60 years with regard to clinical and radiographic outcomes, survivorship, complication rate and revisions. MATERIAL AND METHODS A consecutive series of one hundred and twenty-one patients (130 hips) younger than 60 years at the time of surgery was enrolled in the study. Primary arthritis (33.8%) and dysplastic hips (30%) were the most common diagnoses. The patients used crutches for 6 weeks to protect femoral components against subsidence and rotational stress. The mean follow-up was 118 months (range 96-156 months). RESULTS At the final evaluation, the mean Harris Hip Score was 98.8. A perioperative periprosthetic fracture occurred in two hips and a perioperative ceramic insert breakage was observed in one hip. One hip had ceramic insert fracture 3.5 years postoperatively. In one hip a dislocation occurred. These two hips (1.5%) were revised due to reasons not associated with the stem. One hip has aseptic asymptomatic polyethylene inlay wear. In two hips squeezing was reported. There were two cases of loosening and migration of stems (1.5%) with osteolysis all around the stems. These patients have moderate thigh pain. The radiological survival is 98.5% and the clinical survival is 100% after 10 years on average. DISCUSSION Although improved clinical results were reported in younger patients with standard cementless stems, some problems still prevail: thigh pain, proximal stress shielding, difficult removal of the stem. In an effort to reduce these problems, Proxima ultra-short anatomical cementless stem was developed. Several studies show that this stem design provides good short- and mid- term results, but only in a limited number of patients and relatively short follow-up. Furthermore, the initial fears of early aseptic loosening due to the absence of diaphyseal fixation were not confirmed. CONCLUSIONS Proxima ultra-short anatomical cementless stem provided excellent mid-term clinical and radiographic results in patients younger than 60 years. Key words: total hip arthroplasty, ultra-short cementless anatomical stem.
Cryopreserved haematopoietic progenitor cells are used to restore autologous haematopoiesis after high dose chemotherapy. Although the cells are routinely stored for a long period, concerns remain about the maximum storage time and the possible negative effect of storage on their potency. We evaluated the effect of cryopreservation on the quality of peripheral stem cell grafts stored for a short (3 months) and a long (10 years) period and we compared it to native products.The viability of CD34+ cells remained unaffected during storage, the apoptotic cells were represented up to 10% and did not differ between groups. The clonogenic activity measured by ATP production has decreased with the length of storage (ATP/cell 1.28 nM in native vs. 0.63 in long term stored products, P < 0.05). Only borderline changes without statistical significance were detected when examining mitochondrial and aldehyde dehydrogenase metabolic activity and intracellular pH, showing their good preservation during cell storage. Our experience demonstrates that cryostorage has no major negative effect on stem cell quality and potency, and therefore autologous stem cells can be stored safely for an extended period of at least 10 years. On the other hand, long term storage for 10 years and longer may lead to mild reduction of clonogenic capacity. When a sufficient dose of stem cells is infused, these changes will not have a clinical impact. However, in products stored beyond 10 years, especially when a low number of CD34+ cells is available, the quality of stem cell graft should be verified before infusion using the appropriate potency assays.
- MeSH
- adaptivní imunita MeSH
- biologická terapie metody MeSH
- buněčná imunita MeSH
- homeostáza fyziologie MeSH
- humorální imunita MeSH
- imunomodulace * imunologie účinky léků MeSH
- lidé MeSH
- mezenchymální kmenové buňky MeSH
- přirozená imunita MeSH
- RNA interference MeSH
- sekvence CRISPR MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
RNA interference (RNAi) designates sequence-specific mRNA degradation mediated by small RNAs generated from long double-stranded RNA (dsRNA) by RNase III Dicer. RNAi appears inactive in mammalian cells except for mouse oocytes, where high RNAi activity exists because of an N-terminally truncated Dicer isoform, denoted DicerO. DicerO processes dsRNA into small RNAs more efficiently than the full-length Dicer expressed in somatic cells. DicerO is expressed from an oocyte-specific promoter of retrotransposon origin, which is silenced in other cell types. In this work, we evaluated CRISPR-based strategies for epigenetic targeting of the endogenous Dicer gene to restore DicerO expression and, consequently, RNAi. We show that reactivation of DicerO expression can be achieved in mouse embryonic stem cells, but it is not sufficient to establish a robust canonical RNAi response.
- MeSH
- buňky 3T3 MeSH
- DEAD-box RNA-helikasy antagonisté a inhibitory genetika MeSH
- embryonální kmenové buňky cytologie metabolismus MeSH
- malá interferující RNA genetika MeSH
- myši MeSH
- promotorové oblasti (genetika) * MeSH
- ribonukleasa III antagonisté a inhibitory genetika MeSH
- RNA interference MeSH
- sekvence CRISPR * MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
