Use of a baseplate with a smaller diameter in reverse shoulder arthroplasty has been recommended, especially in patients with a small glenoid or insufficient bony stock due to severe glenoid wear. However, effect of a smaller baseplate on stability of the glenoid component has not been evaluated. The purpose of this study was to determine whether a smaller baseplate (25 mm) is beneficial to the initial primary stability of the glenoid component compared to that with a baseplate of a commonly used size (29 mm) by finite element analysis. Computed tomography (CT) scans of fourteen scapulae were acquired from cadavers with no apparent deformity or degenerative change. Glenoid diameter corresponding to the diameter of the inferior circle of glenoid was measured using a caliper and classified into the small and large glenoid groups based on 25mm diameter. CT slices were used to construct 3-dimensional models with Mimics (Materialise, Leuven, Belgium). A corresponding 3D Tornier Aequalis® Reversed Shoulder prosthesis model was generated by laser scanning (Rexcan 3D Laser Scanner, Solutionix, Seoul, Korea). Glenoid components with 25mm and 28mm diameter of the baseplate were implanted into the scapular of small and large glenoid group, respectively. Finite element models were constructed using Hypermesh 11.0 (Altair Engineering, Troy, MI, USA) and a reverse engineering program (Rapidform 3D Systems, Inc., Rock Hill, SC, USA). Abaqus 6.10 (Dassault Systemes, Waltham, MA) was used to simulate 30o, 60o, and 90o glenohumeral abduction in the scapular plane. Single axial loads of 686N (1 BW) at angles of 30o, 60o, and 90o abduction were applied to the center of the glenosphere parallel to the long axis of the humeral stem. Relative micromotion at the middle and inferior thirds bone–glenoid component interface, and distribution of bone stress under the glenoid component and around the screws were analyzed. Wilcoxon's rank-sum test was used for statistical comparison and p < 0.05 was considered as a minimum level of statistical significance.Background
Methods
The purpose of this study was to assess the efficacy of newly designed topical administration of tranexamic acid (TXA) in reducing postoperative bleeding in total hip arthroplasty (THA) and bipolar hip hemiarthroplasty (BHA). Consecutive series of 160 hip arthroplasty were enrolled for this study. Topical administration of TXA was done in group 1(40 hips of THA and 40 hips of BHA). We compared the amount of blood loss and rates of postoperative transfusion with group 2 (40 cases of THA and 40 cases of BHA) in which TXA solution was not appliedPurpose
Method
Topical application of tranexamic acid (TXA) to bleeding wound surfaces reduces blood loss in patients undergoing some major surgeries, without systemic complications. The objective of this study was to determine if TXA applied topically reduced postoperative bleeding and transfusion rates after primary total hip arthroplasty (THA) and primary bipolar hemiarthroplasty (BA). We retrospectively compared 77 patients undergoing hip arthroplasty surgery in which tranexamic acid was routinely used, to a group of 70 patients from a similar time frame prior to the introduction of tranexamic acid use. In the former group 40 patients had THA and 37 patients BA; in the latter group 35 patients underwent THA and 35 patients BA. In both THA and BA, the joint was bathed in TXA solution (at a concentration of 3.0 g TXA per 100 mL saline) at three points during the procedure. The primary outcome was blood loss calculated from the difference between the preoperative hemoglobin level and the corresponding lowest postoperative value or hemoglobin level prior to transfusion.Purpose
Methods
DNA damage induced by systemic drugs or local γ-irradiation drives disc degeneration and DNA repair ability is extremely important to help prevent bad effects of genotoxins (DNA damage inducing agents) on disc. DNA damage (genotoxic stress) and deficiency of intracellular DNA repair mechanisms strongly contribute to biological aging. Moreover, aging is a primary risk factor for loss of disc matrix proteoglycan (PG) and intervertebral disc degeneration (IDD). Indeed, our previous evidences in DNA repair deficient Summary Statement
Introduction
The natural history of osteonecrosis of the femoral head (ONFH) is not cleanly understood, but most of them progresse to the joint destruction and requires total hip replacement arthroplasty. There are several head preserving procedure, but no single therapeutic method proved to be effective in preventing progression of the disease. The possibility has been raised that implantation of bone marrow containing osteogenic precursors may be effective in the treatment of this disease. However, there are no long-term follow-up results of cell therapy for ONFH. AS far as we know, there are no reports about bone graft and cell therapy for ONFH. Therefore, we performed a prospective clinical and radiological evaluation on ONFH treated with core decompression combined with autoiliac bone graft and an implantation of autologous bone marrow cells as a therapeutic method of ONFH. Sixty-one hips in 52 patients with ONFH were included in this study. The average follow-up of the patients was 68 (60∼88) months. The necrotic lesions were classified according to their size and location, and we compared the results.Introduction
Materials and Methods
This study analyzed the long-term results of cementless total hip arthroplasty using an extensively porous coated stem in patients younger than 45 years old. The clinical and radiographic results of 45 hips from 38 patients who underwent cementless total hip replacement arthroplasty with an AML prosthesis were reviewed retrospectively. The average follow-up was 12 years (range, 10–15 years).Purpose
Materials and Methods
All Polyethylene Tibial components in Total Knee Arthroplasty have been in use for some years, studies showing equivalent results to Total Knee Arthroplasty (TKA) with metal-backed Tibial components at 10 years have shown no significant difference between the two on radiostereometric analysis and revision rates[1]. Post operative patient outcome data using standard metal-backed Tibial components is widely reported in the literature. This study is looking at patient outcomes following All-polyethylene tibial component TKA. We hypothesize that using standard patient outcome measures, an improvement comparable with that expected for metal-backed tibial component TKA will be shown with All-polyethylene tibial component TKA. Between August 2006 and August 2008, 229 all-polyethylene tibial component TKA were implanted at the elective orthopedic unit. The choice of implant was entirely dependent on surgeon's preference. Of the 229 patient's, 225 details were available for review, 27 did not wish to take part in the study and 1 patient died a year following surgery of an unrelated illness. The remaining 197 patients agreed to take part in the study. The patient's were contacted either in person or over the telephone and asked to completed questionnaires for standard knee scoring. These included: the Oxford Knee Score (OKS), the WOMAC Score and the SF-12 Score, both pre-operatively and post operatively.Objectives
Methods
The implantation of DIAM in interspinous space is believed to act as facet joints and provides stability to operated segment by shifting instantaneous axis of rotation forward in lordotic disorders. In this retrospective study, the patients who underwent lumbar surgery with DIAM (Medtronic Sofamor, Danek) spacer implants were followed up with an aim to evaluate the clinical outcomes. To our knowledge, this is the largest series with longest follow up. Patients who underwent lumbar surgery (discectomy and decompression) with concomitant placement of DIAM spacer within a 36-months period were included. A total of 52 patients including equal number of male (n=26) and female (n=26), were followed up for 12 to 45 months (Mean: 22 months).Introduction
Material Methods
We present the results of a single centre, prospective study to evaluate the clinical and radiographic outcomes of anterior cervical decompression and replacement (ACDR) using the NuNec(tm) Cervical Arthroplasty System (Pioneer Surgical Technology, Marquette, Mich., USA). 36 patients with radiculopathy/myelopathy, who failed to respond to conservative measures, were included. Pain and function were evaluated by Visual Analogue score for Neck pain (VAS-NP) and Arm pain (VAS-AP), Neck disability index (NDI) and SF-36 questionnaires. Radiological assessments include assessing overall range of movement (ROM) and at functional segment unit (FSU). Statistical analysis was completed using SPSS 16.0 statistical package (SPSS Inc, Chicago, IL). Appropriate parametric (A paired t-test) and non parametric tests (Wilcoxon signed-rank test) were used to assess the statistical significance (p<0.05). The average age at operation was 51 years (range 35 - 77years). 8 patients received ACDR at one-level, 15 had 2-level surgery, 12 had 3-level surgery and 1 had a 4-level surgery. At the time of final follow-up (Mean 14.25 months, Range 12- 22.5 months) the mean NDI improved from 49.35; to 33.78 (p< 0.001). There statistically significant improvement note in VAS-NP (Post-op3.65, Pre-op:8.16, p<0.001), VAS-AP (Post-op:3.12, Pre-op:7.32, p<0.001) and SF-36BP (pre-op:29.15, post-op:37.18, p<0.002). The overall global ROM movement was preserved (pre-op:46.80±10.52, post-op:45.04±11.53) and an improvement in ROM at FSU was observed (pre-op:16.60±8.50, post-op:20.22±12.22) at final follow–up.Background
Methodology and Results
Although the clinical manifestation of ONFH is well summarized as forms of various stages, its etiology, natural history or epidemiology has not been clearly elucidated yet. With this study, we wanted to find out the estimated annual incidence, epidemiologic characteristics and the effect of known risk factors of ONFH. Therefore we can understand the disease better to provide optimal management to the patients. Among 133 189 patients who diagnosed as osteonecrosis of femoral head (ONFH) in database of national health insurance system in Korea from 2002 to 2006, three hundreds an eighty-two samples were randomly extracted with 5% error range in 95% confidence interval. With a structured worksheet, medical records and radiographs of each sample were reviewed at corresponding clinic or hospital by authors and trained orthopedic surgeons. With these data, we calculated the prevalence and associated risk factors. The mean number of annual requests was 23 466. Among 382 samples, two hundreds and seventy-four were confirmed to have ONFH. Diagnostic accuracy was 71.7 %. Diagnosis was more accurate when the patient was male or hospitalized. After the logistic regression analysis, calculated diagnostic accuracy during 2002 and 2006 was 60.3% (51 823/85 987). The annual predicted number of cases of ONFH during this period was 14 103. It corresponds to 28.91 patients per 100 000 populations. Alcohol abuse was noted in 45% and 22% was related to use of steroid. 37% showed bilateral involvement. Bone graft procedures in any kind was the most frequently performed joint preserving procedure. With this, the first epidemiologic study for ONFH in Korea, we estimated nationwide annual prevalence of ONFH as 28.91 per 100,000 populations during 2002 and 2006. There is an absolute male predominance. Alcohol abuse is the most frequent risk factors. We believe that this result can serve as a baseline data for understanding the epidemiology, clinical characteristics and treatment of ONFH.
Mesenchymal stem cells (MSCs) are exciting candidates for cellular repopulation and repair in intervertebral disc degeneration (IDD). Our purpose is to investigate the interaction between MSCs and nucleus polposus cells (NPCs) and to determine viability of MSC in the intervertebral disc (IVD). Human NPCs and hMSCs were co-cultured in pellet system at different ratios. Proteoglycans were measured and normalized with DNA content. Histological analysis were also performed. Rabbit MSCs from bone marrow were trasduced with LacZ reporter gene and were injected into a rabbit IVD. Rabbits were sacrificed postoperatively at 3, 6, 12 and 24 weeks. Histological analysis was performed. Co-culturing of hNPCs with hMSCs resulted in increases proteoglycans as compared with hNPCs alone. Histological examination of the injected IVDs revealed presence of MSCs without apparent decrease in numbers or diminishment of protein production at 3, 6, 12 and 24 weeks. The data from this study show that there is a synergistic effect between MSCs and NPCs resulting in upregulated proteoglycan synthesis in-vitro. MSC remain viable and continue to express an ex-vivo transduced protein for up to 24 weeks. These results suggest that MSCs can survive in the harsh environment of the IVD and may favourably modify ECM production.
Current therapies for intervertebral disc degeneration are aimed at treating the pathologic and disabling conditions arising from discopathy rather than directly treating the underlying problem of disc degeneration. Our group is exploring the potential of cell therapy to repopulate the disc and stop the progressive loss of proteoglycans. Stem cells appear to be excellent candidates for this purpose, based on their ability to differentiate along multiple connective tissue lineages. The purpose of this study is to investigate the interaction between stem cells and nucleus polposus cells to test the feasibility of stem cell therapy for the treatment of disc degeneration. Human nucleus polposus cells (NPCs) were isolated from patients undergoing disc surgery and were co-cultured for 2 weeks with muscle-derived stem cells (MdSCs) from 3-week-old mdx mice in monolayer culture system at different ratio with or without added TGF-β1. Each well contained an admixture of cells with NPC-to-SC ratios of 0:100, 25:75, 50:50, 75:25, and 100:0. Proteoglycan synthesis and DNA content were measured. Co-culturing of NPCs with MdSCs in the monolayer culture system resulted in vigorous increases in proteoglycans synthesis as compared with NPCs alone and MdSCs alone both with and without TGF-β1. The increases were on the 200% for an NPC-to-MDSC ratio of 75:25. Addition of TGF-β1 to the NPC and MDSC co-cultures resulted in further increases up to 400%. DNA content also increased with co-culture. The data from this study show that there is a synergistic effect between stem cells and nNPC resulting in upregulated proteoglycan synthesis in vitro. The observed benefits of co-culture might be due either to stem cell plasticity, the stem cells trans-differentiation towards chondrocyte-like cells, or the stimulation of NPC by agents synthesised by stem cells or other mechanisms. Elucidation of the precise mechanisms of action may permit development of strategies to optimise the synergistic effects in vivo. These results support the feasibility of developing a stem cell therapy approach to treat and prevent intervertebral disc degeneration.
