Biomechanical comparison of lag screw and non-spiral blade fixation of a novel femoral trochanteric nail in an osteoporotic bone model.

There is no consensus regarding the advantages of the lag screw type over the blade type for treating femoral trochanteric fractures. We aimed to investigate whether non-spiral blade (Conventional-Blade, Fid-Blade) nails provide better biomechanical fixation than lag screws in a severe osteoporotic bone model. Different severities of osteoporotic cancellous bone were modelled using polyurethane foam blocks of three densities (0.24, 0.16, and 0.08 g/cm3). Three torsional tests were performed using each component for each density of the polyurethane block, and the maximum torque was recorded; subsequently, the energy required to achieve 30° rotation was calculated. Using a push-in test, the maximum force was recorded, and the energy required to achieve 4-mm displacement was calculated. For 0.08-g/cm3 density, the peak torques to achieve 30° rotation, energy required to achieve 30° rotation, peak force to achieve 4-mm displacement, and energy required to achieve 4-mm displacement were significantly greater for Conventional-Blade and Fid-Blade than those for Lag Screw. The fixation stability of the blade-type Magnum nail component is better than that of the lag screw type under any test condition. The blade-type nail component may have better fixation stability than the lag screw type in a severe osteoporotic bone model.

Prevention of osteonecrosis by intravenous administration of human peripheral blood-derived CD34-positive cells in a rat osteonecrosis model.

Aseptic idiopathic osteonecrosis of the femoral head is a painful disorder of the hip that can lead to collapse of the femoral head and the need for total hip replacement following joint destruction. Treatment of this disease still remains a clinical challenge. Adult human circulating CD34(+) cells have been demonstrated to contribute to vasculogenesis and osteogenesis in immunodeficient rat non-union models in vivo. We hypothesized and proved that the transplantation of CD34(+) cells could have a role for improvement of osteonecrosis by promoting vasculogenesis and osteogenesis. Vascular deprivation-induced femoral head necrosis was developed in immunodeficient rats and we then administered human G-CSF mobilized CD34(+) cells intravenously. At 4 weeks after administration, the structure of the femoral head and neck were evaluated histologically and morphometrically with haematoxylin and eosin (H&E) staining and micro-CT imaging. Microangiography was carried out for macroscopic evaluation of neovascularization, and the contribution of human cells to vasculogenesis and osteogenesis was evaluated by immunofluorescent staining with human-specific antibodies. Our treatment resulted in an obvious improvement of osteonecrosis after CD34(+) cell administration and demonstrated the differentiation potential of CD34(+) cells into endothelial cells and osteoblasts. In conclusion, this new therapeutic approach using circulating cell fraction could be a promising cell-based therapy for early-stage osteonecrosis of the hip.

Transplantation of bone marrow mononuclear cells enables simultaneous treatment with osteotomy for osteonecrosis of the bilateral femoral head.

BACKGROUND: Bone marrow derived mononuclear cells (BMMNCs) have the advantage of promoting both angiogenesis and osteogenesis. In this report, BMMNCs were transplanted into the affected area of one hip using interconnected porous calcium hydroxyapatite (IP-CHA) in two patients, while the other hip was simultaneously treated with transtrochanteric rotational osteotomy (TRO). This case report documents the potential of BMMNCs with IP-CHA for bone repair at the lesion of osteonecrosis of the femoral head. CASE REPORT: Two patients whose progression of osteonecrosis was stage 3 at one hip and stage 2 at the other hip. Firstly, TRO was performed on the collapsed side. Bone marrow aspirates were obtained from the iliac crest and were centrifuged with a cell separator during the procedure of TRO. BMMNCs were seeded into the IP-CHA and were transplanted to the lesion of osteonecrosis. Bone consolidation of transition zone on the cell-seeded femoral head was observed postoperatively at three or six months. The radiographs more than 22 months after surgery demonstrated shrinking of the extent of osteonecrosis, and no progression of collapse was observed. CONCLUSIONS: We described two case reports of simultaneous surgical treatment for osteonecrosis of the bilateral femoral head using TRO for one hip in combination with transplantation of BMMNCs for the other hip. Short term results of this procedure are satisfactory without progression of collapse. Transplantation of BMMNCs may be a beneficial treatment for bone repair in the condition of osteonecrosis.

Multiple drillings of the acetabular fossa induce early joint remodeling after rotational acetabular osteotomy for hip dysplasia.

INTRODUCTION: We previously observed medial and/or lateral expansion of the subchondral bone in the acetabulum 3 years postoperatively in two out of three cases in which rotational acetabular osteotomy (RAO) was performed. Then we performed multiple drillings at the acetabular fossa in order to induce expansion of the medial subchondral bone in the acetabulum. The purpose of this study is to evaluate the effect of multiple drillings on early joint remodeling after RAO. PATIENTS AND METHODS: Twenty-one women (21 joints) who had undergone RAO with multiple drillings at acetabular fossa (group D) were included. As a control group, 12 women (14 joints) without drillings in RAO procedure were observed (group C). The center-edge angle (CE angle), acetabular roof obliquity (AC angle), head lateralization index (HLI), and the angle between medial and lateral edge of acetabular roof (LOM angle) were measured on the radiographs preoperatively, at 1 month, 2 years postoperatively, and at the last follow-up. RESULTS: As regards the mean CE angle, AC angle, and HLI, there was no significant difference between the two groups. The mean LOM angle at 2 years and the last follow-up demonstrated significant difference between the two groups. INTERPRETATION: Biomechanical and anatomical changes after RAO cause increasing stress to the medial side of the acetabulum. Moreover, bone marrow-stimulating procedure at acetabular fossa might be beneficial to develop early joint remodeling affected by bone marrow derived cells such as mesenchymal stem cells.

Rotational acetabular osteotomy for advanced osteoarthritis secondary to dysplasia of the hip. Surgical technique.

BACKGROUND: Satisfactory intermediate and long-term results of rotational acetabular osteotomy for the treatment of early osteoarthritis secondary to developmental dysplasia of the hip have been reported. The purpose of this study was to examine the results of rotational acetabular osteotomy in patients with advanced osteoarthritis secondary to developmental dysplasia of the hip. METHODS: We performed a retrospective review of the results of rotational acetabular osteotomy in forty-three patients (forty-three hips). All of the patients had radiographic evidence of advanced-stage osteoarthritis, defined as narrowing of the joint space with cystic radiolucencies and small osteophytes according to the staging system of the Japanese Orthopaedic Association. Forty-one patients were female, and two were male. The mean age was 43.8 years at the time of surgery, and the mean duration of follow-up was 8.5 years. Clinical follow-up was performed with use of the system of Merle d'Aubigné and Postel. The center-edge angle, acetabular roof angle, head lateralization index, and minimum width of the joint space were measured on radiographs made preoperatively, postoperatively, and at the time of final follow-up. Postoperative joint congruency was classified into four grades. RESULTS: The mean preoperative Merle d'Aubigné clinical score was 13.3 points, which improved to a mean of 15.4 points at the time of the latest follow-up (p < 0.0001). The mean center-edge angle improved from 0.7 degrees preoperatively to 29 degrees at three months postoperatively (p < 0.0001), the mean acetabular roof angle improved from 30 degrees to 11 degrees (p < 0.0001), the mean head lateralization index improved from 0.69 to 0.65 (p < 0.01), and the mean minimum width of the joint space improved from 2.2 to 2.5 mm (p < 0.0003). Ten hips had radiographic evidence of progression of osteoarthritis. Kaplan-Meier survivorship analysis, with radiographic signs of progression of osteoarthritis as the end point, predicted a ten-year survival rate of 72.2%. CONCLUSIONS: Rotational acetabular osteotomy for advanced osteoarthritis secondary to dysplasia of the hip in properly selected patients can improve clinical scores and is associated with a lack of radiographic signs of progression of osteoarthritis in most patients.

[Treatment of osteonecrosis of the femoral head with implantation of autologous bone-marrow mononuclear cells].

Idiopathic osteonecrosis of the femoral head commonly develops during adolescence and in the prime of adulthood. In Japan, joint-preserving procedures such as transtrochanteric rotational osteotomy, femoral varus osteotomy and vascularized bone grafting are often the surgical treatments of choice. However, the results of these procedures are not necessarily satisfactory. These procedures force patients to endure longer waits for their entire treatment. In addition, it is often difficult for surgeons to choose the appropriate treatment, especially in patients who have bilateral extensive osteonecrosis. We reported transplantation of bone marrow mononuclear cells for osteonecrosis of the femoral head and short-term results.

Rotational acetabular osteotomy for advanced osteoarthritis secondary to dysplasia of the hip.

BACKGROUND: Satisfactory intermediate and long-term results of rotational acetabular osteotomy for the treatment of early osteoarthritis secondary to developmental dysplasia of the hip have been reported. The purpose of this study was to examine the results of rotational acetabular osteotomy in patients with advanced osteoarthritis secondary to developmental dysplasia of the hip. METHODS: We performed a retrospective review of the results of rotational acetabular osteotomy in forty-three patients (forty-three hips). All of the patients had radiographic evidence of advanced-stage osteoarthritis, defined as narrowing of the joint space with cystic radiolucencies and small osteophytes according to the staging system of the Japanese Orthopaedic Association. Forty-one patients were female, and two were male. The mean age was 43.8 years at the time of surgery, and the mean duration of follow-up was 8.5 years. Clinical follow-up was performed with use of the system of Merle d'Aubigné and Postel. The center-edge angle, acetabular roof angle, head lateralization index, and minimum width of the joint space were measured on radiographs made preoperatively, postoperatively, and at the time of final follow-up. Postoperative joint congruency was classified into four grades. RESULTS: The mean preoperative Merle d'Aubigné clinical score was 13.3 points, which improved to a mean of 15.4 points at the time of the latest follow-up (p < 0.0001). The mean center-edge angle improved from 0.7 degrees preoperatively to 29 degrees at three months postoperatively (p < 0.0001), the mean acetabular roof angle improved from 30 degrees to 11 degrees (p < 0.0001), the mean head lateralization index improved from 0.69 to 0.65 (p < 0.01), and the mean minimum width of the joint space improved from 2.2 to 2.5 mm (p < 0.0003). Ten hips had radiographic evidence of progression of osteoarthritis. Kaplan-Meier survivorship analysis, with radiographic signs of progression of osteoarthritis as the end point, predicted a ten-year survival rate of 72.2%. CONCLUSIONS: Rotational acetabular osteotomy for advanced osteoarthritis secondary to dysplasia of the hip in properly selected patients can improve clinical scores and is associated with a lack of radiographic signs of progression of osteoarthritis in most patients. LEVEL OF EVIDENCE: Therapeutic Level IV.

The Effects of lithium and Zinc Ions on the Pattern of Acidic Glycans in the Sea Urchin (Hemicentrotus pulcherrimus) Embryo: (sea urchin embryo/lithium/zinc/acidic glycan/UEA-I).

Among several acidic glycan components found in Hemicentrotus embryos, the "F"- and "S"-components were specifically affected by treatment with Li+ and Zn2+ , respectively. The amount of the "F"-component in Li+ -treated embryos was about 60% that in normal embryos. This fact was in accordance with the reduced alcian blue staining of the surfaces in Li+ -treated embryos. Moreover, the "F"-component in Li+ -treated embryos appeared to be composed of two subcomponents, while in normal and Zn2+ -treated embryos it appeared to be single. The "S"-component in Zn2+ -treated embryos was about 8% that in normal embryos. According to histochemistry with a lectin probe, it was found that UEA-I was much more strongly associated with a hyaline layer in Li+ -treated than in normal and Zn2+ -treated embryos. Li+ -treated embryos developed into exogastrulas, which were divided by a constriction into two parts; an animal half which stained intensely with alcian blue, and a vegetal half which stained poorly. On the other hand, Zn2+ -treated embryos remained as permanent blastulas. Considering the above, it is suggested that change in the acidic glycan pattern leads to alterations in the morphogenesis of sea urchin embryos.

Melittin, a Component of Bee Venom, Activates Unfertilized Sea Urchin Eggs: (melittin/activation/sea urchin egg).

Melittin, which is known to stimulate phospholipase A, in many cells, caused as much elevation of fertilization membranes and increase in respiration of unfertilized eggs of the sea urchins Anthocidaris crassispina and Hemicentrotus pulcherrimus as normal fertilization. In melittin-activated eggs, amino acid transport was decreased to less than that of unfertilized eggs, nucleoside transport was only slightly, activated, protein synthesis was rather inhibited and neither DNA synthesis nor cleavage was observed. It is concluded that although melittin induces the cortical reaction and activation of respiration in unfertilized eggs, its cytotoxicity prevents any "late changes".

GENERAL PATTERN, 35 SO4 -INCORPORATION AND INTRACELLULAR LOCALIZATION OF GLYCANS IN DEVELOPING SEA URCHIN (ANTHOCIDARIS) EMBRYOS.

Glycosaminoglycan (GAG) prepared from sea urchin embryos (Anthocidaris crassispina) at various stages with or without pulse 35 SO4 -labelling was separated into various fractions by chromatography on DEAE-cellulose with a linear NaCl concentration gradient: fraction "P" (nonacidic) and fractions "A" through "F" (of increasing acidities). The 35 SO4 -radioactivity was negligible in "P" and "A", largest in "B" and "C", and decreased in the other fractions three alphabetical order. During development (hatched blastulae to gastrulae) the glycans in fractions "P" and "A" decreased in amount, whereas those in "E" and "F" increased. "E" contained heparin-like (AMPS-1) and dermatanpolysulfate-like (AMPS-2) GAG in addition to a sulfated fucogalactan-like (E1 ) glycan. Another sulfated fucogalactan-like (F1 ) glycan was found in "F". A sulfated polysialic acid-like (S1 ) glycan was found in "C". An EDTA-extract of gastrulae gave AMPS-2, E1 and F1 . The mitochondria-rich fraction gave AMPS-1, whereas the yolk granule-rich fraction gave S1 . Most of the other still unidentified components in "B", "C", and "D" appeared to be derived from glycoproteins and were mainly located in the crude yolk-mitochondrial and cytosol fractions.