Clinical Impact of Corrective Cast Treatment for Early Onset Scoliosis: Is It a Worthwhile Treatment Option to Suppress Scoliosis Progression Before Surgical Intervention?

BACKGROUND: Although corrective cast (CC) has been back in use for the treatment of early onset scoliosis (EOS), no studies have reported how clinically meaningful CC was in comparison with brace-only treatment (BT) in EOS. The aim of this study was to investigate the effect of CC treatment in terms of suppression of scoliosis progression before surgery. METHODS: This study was designed to conduct a comparison of patients treated at 2 spine institutions differing in treating methods (one: mainly CC with brace, the other: BT). Applying casts were performed without general anesthesia and repeatedly with the interval of 2 to 6 months combined with corrective brace application called alternatively repetitive cast and brace treatment (ARCBT). In total, 58 patients met the following criteria: (1) age at the first visit ≤6 years, (2) scoliosis ≥40 degrees, (3) conservative treatment≥2 years. Patients with congenital scoliosis were excluded in this study. In total, 58 patients were divided into 2 groups; cast/brace group (C/B-G) and BT group (B-G). RESULTS: There were no significant differences of diagnosis (P=0.2773), sex (P=0.0670), age at the first visit (P=0.1457), scoliosis magnitude (P=0.1980), and duration for conservative treatment (P=0.2578) between 2 groups. Most of the patients who were treated with ARCBT, were switched to BT due to lower compliance for CC after the age of around 7 years. The progression of scoliosis during ARCBT and BT were 4.4 and 5.8 degree/y, respectively. Those during ARCBT in C/B-G was 2.8 degree/y comparing with 8.4 degree/y after switch to BT after 7 years of age. There was a significant difference between scoliosis progression during ARCBT in C/B-G and that of B-G (P=0.0086). CONCLUSIONS: This study showed that ARCBT had a significant impact on suppression of scoliosis progression compared with BT in EOS. However, the termination of cast application and the switch to BT may be still a clinical question considering the time to surgical intervention. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Profiling microRNA expression during fracture healing.

BACKGROUND: The discovery of microRNA (miRNA) has revealed a novel type of regulatory control for gene expression. Increasing evidence suggests that miRNA regulates chondrocyte, osteoblast, and osteoclast differentiation and function, indicating miRNA as key regulators of bone formation, resorption, remodeling, and repair. We hypothesized that the functions of certain miRNAs and changes to their expression pattern may play crucial roles during the process of fracture healing. METHODS: Standard healing fractures and unhealing fractures produced by periosteal cauterization at the fracture site were created in femurs of seventy rats, with half assigned to the standard healing fracture group and half assigned to the nonunion group. At post-fracture days 3, 7, 10, 14, 21, and 28, total RNA including miRNA was extracted from the newly generated tissue at the fracture site. Microarray analysis was performed with miRNA samples from each group on post-fracture day 14. For further analysis, we selected highly up-regulated five miRNAs in the standard healing fracture group from the microarray data. Real-time PCR was performed with miRNA samples at each time point above mentioned to compare the expression levels of the selected miRNAs between standard healing fractures and unhealing fractures and investigate their time-course changes. RESULTS: Microarray and real-time polymerase chain reaction (PCR) analyses on day 14 revealed that five miRNAs, miR-140-3p, miR-140-5p, miR-181a-5p, miR-181d-5p, and miR-451a, were significantly highly expressed in standard healing fractures compared with unhealing fractures. Real-time PCR analysis further revealed that in standard healing fractures, the expression of all five of these miRNAs peaked on day 14 and declined thereafter. CONCLUSION: Our results suggest that the five miRNAs identified using microarray and real-time PCR analyses may play important roles during fracture healing. These findings provide valuable information to further understand the molecular mechanism of fracture healing and may lead to the development of miRNA-based tissue engineering strategies to promote fracture healing.

Effects of parathyroid hormone 1-34 on osteogenic and chondrogenic differentiation of human fracture haematoma-derived cells in vitro.

Parathyroid hormone (PTH) 1-34 has been shown to accelerate fracture healing. Previously, we reported that progenitor cells with osteogenic and chondrogenic potential exist in human fracture haematoma, suggesting that the fracture haematoma-derived progenitor cells (HCs) contribute to fracture healing. However, there has been no study investigating the effect of PTH on HCs. We investigated the effect of pulsatile and continuous PTH treatment on human fracture HCs in vitro. HCs were isolated from seven patients. The HCs were divided into four groups: growth medium; control [osteogenic medium (OM) without PTH]; PTH-C (OM with continuous PTH); and PTH-P (OM with pulsatile PTH) groups. Osteogenic differentiation potential and proliferation of HCs were compared among the four groups. For chondrogenesis, the HCs were divided into two groups: control [chondrogenic medium (CM) without PTH]; and PTH-C (CM with continuous PTH) groups, and chondrogenic differentiation potential was analysed. PTH treatment did not affect cell proliferation, regardless of the mode of administration. Osteogenic activity was also not significantly affected by continuous PTH treatment but significantly inhibited by pulsatile PTH treatment. Conversely, chondrogenic differentiation was significantly inhibited by continuous PTH treatment. Our results revealed that PTH treatment on HCs, either continuous or pulsatile, does not exhibit any positive effect, and indicates that exogenous PTH administration after fracture has no effect on HCs. PTH may not have a positive effect at the fracture site during the early stage of fracture healing in which haematoma formation occurs. Copyright © 2013 John Wiley & Sons, Ltd.

Comparative analysis of rat mesenchymal stem cells derived from slow and fast skeletal muscle in vitro.

PURPOSE: Skeletal muscle comprises different kinds of muscle fibres that can be classified as slow and fast fibres. The purpose of this study was to compare the yield, proliferation, and multi-potentiality of rat mesenchymal stem cells (MSCs) from the tibialis anterior (TA; fast muscle) and soleus (SO; slow muscle) in vitro. METHODS: The TA and SO muscles were harvested, and isolated cells were plated. After two hours, the cells were washed extensively to remove any cell that did not adhere to the cell culture plate. The adherent cells, namely MSCs, were then cultured. Both types of MSCs were differentiated toward the osteogenic, chondrogenic and adipogenic lineages using lineage specific induction factors. RESULTS: The colony-forming unit fibroblast (CFU-F) assay revealed that the SO contained significantly higher quantities of MSCs than the TA. The self-renewal capacity of MSCs derived from the TA was significantly higher at later passages (passage 9-11). Both types of MSCs exhibited similar cell surface antigens to bone marrow (BM)-derived MSCs and were positive for CD29, CD44, and CD90 and negative for CD11b, CD34, and CD45. TA-derived MSCs were superior in terms of osteogenic differentiation capacity, but there was no significant difference in chondrogenic and adipogenic differentiation capacity. CONCLUSION: Our results demonstrated significant differences in the properties of muscle-derived MSCs from different muscle types (i.e. fast or slow muscles). The greater expandability and osteogenic differentiation ability of TA-derived MSCs suggests that fast muscle may be a better source for generating large numbers of MSCs for bone regeneration.

Efficient derivation of osteoprogenitor cells from induced pluripotent stem cells for bone regeneration.

PURPOSE: There has been great interest in the use of induced pluripotent stem cells (iPSCs) in bone regenerative strategies. To generate osteoprogenitor cells from iPSCs, the most widely used protocol relies on an intermediate using embryoid body (EB) formation. We hypothesized that an osteoprogenitor cell population could be efficiently generated from iPSCs by employing a "direct-plating method" without the EB formation step. METHODS: Murine iPSC colonies were dissociated with trypsin-EDTA, and obtained single cells were cultured on gelatin-coated plates in MSC medium and FGF-2. Adherent homogeneous fibroblast-like cells obtained by this direct-plating technique were termed as direct-plated cells (DPCs). Expression levels of Oct-3/4 mRNA were analysed by real-time PCR. DPCs were evaluated for cell-surface protein expression using flow cytometry. After osteogenic induction, osteogenic differentiation ability of DPCs was evaluated. RESULTS: The expression level of Oct-3/4 in DPCs was significantly down-regulated compared to that observed in iPSCs, suggesting that the cells lost pluripotency. Flow cytometry analysis revealed that DPCs exhibited cell-surface antigens similar to those of bone marrow stromal cells. Furthermore, the cells proved to have a high osteogenic differentiation capacity, which was confirmed by the significant increase in alkaline phosphatase activity, the expression levels of osteogenic genes, and calcium mineralization after 14-day osteogenic induction. CONCLUSIONS: These findings indicate that our novel direct-plating method provides a clinically applicable, simple, and labour-efficient system for generating large numbers of homogeneous iPSC-derived osteoprogenitor cells for bone regeneration.

Effect of low-intensity pulsed ultrasound on bone morphogenetic protein 7-induced osteogenic differentiation of human nonunion tissue-derived cells in vitro.

OBJECTIVES: Low-intensity pulsed ultrasound (US) has been shown to have positive effects on the healing of nonunions, and bone morphogenetic protein 7 (BMP-7) is known to be a strong stimulator of osteogenic differentiation. Recently, we showed that nonunion tissue contains multilineage mesenchymal progenitor cells, suggesting that nonunion tissue-derived cells may play an important role during the healing process of nonunions. In this study, we investigated whether low-intensity pulsed US promoted BMP-7-induced osteogenic differentiation of nonunion tissue-derived cells in vitro. METHODS: Nonunion tissue-derived cells were isolated from 7 patients. The cells were divided into two groups: (1) BMP-7 alone, consisting of nonunion tissue-derived cells cultured in osteogenic medium containing BMP-7 without low-intensity pulsed US treatment; and (2) BMP-7 + low-intensity pulsed US, consisting of nonunion tissue-derived cells cultured in osteogenic medium containing BMP-7 with low-intensity pulsed US treatment. The osteogenic differentiation potential and proliferation of nonunion tissue-derived cells were compared between the two groups. RESULTS: The alkaline phosphatase activity, gene expression levels of alkaline phosphatase and runt-related transcription factor 2, and mineralization were higher in the BMP-7 + low-intensity pulsed US group than in the BMP-7-alone group. There was no significant difference in cell proliferation between the two groups. CONCLUSIONS: These findings show a significant effect of low-intensity pulsed US on the osteogenic differentiation of nonunion tissue-derived cells induced by BMP-7. This study may provide substantial evidence for the clinical combined application of BMP-7 and low-intensity pulsed US for nonunion treatment.

In vitro hypertrophy and calcification of human fracture haematoma-derived cells in chondrogenic differentiation.

PURPOSE: The haematoma at a fracture site plays an important role in fracture healing. Previously, we demonstrated that a fracture haematoma contains multilineage mesenchymal progenitor cells. We postulated that the haematoma provided a source of chondrogenic cells for endochondral ossification during fracture healing and preservation of the cells contributed to biological fracture healing. In this study, we investigated whether haematoma-derived cells (HCs) could differentiate into hypertrophic chondrocytes and finally induce calcification of the extracellular matrix in vitro. METHODS: Fracture haematomas were obtained from four patients. HCs were cultured for five weeks under conditions that induce chondrogenic differentiation, followed by two weeks of hypertrophic induction using a pellet culture system. The pellets were analysed histologically and immunohistochemically. The gene expression levels of chondrogenic, hypertrophic, osteogenic, and angiogenic markers were measured by real-time PCR. RESULTS: The histological and immunohistochemical analyses revealed that HCs differentiated into chondrocytes and hypertrophic chondrocytes, followed by calcification of the extracellular matrix. This sequential differentiation was also reflected in the gene expression profiles. After chondrogenic induction, expression of osteogenic and angiogenic markers was not significantly upregulated. However, the expression of these markers was significantly upregulated following hypertrophic induction. These in vitro observations mimicked the process of endochondral ossification during fracture healing. CONCLUSIONS: Our results suggest that the fracture haematoma may offer a source of cells with chondrogenic potential that play key roles in endochondral ossification during fracture healing. These findings support the opinion that the haematoma should be preserved for biological fracture healing.

Low-intensity pulsed ultrasound enhances BMP-7-induced osteogenic differentiation of human fracture hematoma-derived progenitor cells in vitro.

OBJECTIVE: To investigate the effect of the combined application of bone morphogenetic protein-7 (BMP-7) and low-intensity pulsed ultrasound (LIPUS) on human fracture hematoma-derived progenitor cells (HCs). METHODS: HCs were isolated from 6 patients. The cells were then divided into 4 groups and cultured: (1) control group, HCs cultured in growth medium without LIPUS; (2) LIPUS group, HCs cultured in growth medium with LIPUS; (3) BMP-7 group, HCs cultured in osteogenic medium containing BMP-7 without LIPUS; and (4) BMP-7 + LIPUS group, HCs cultured in osteogenic medium with LIPUS. Osteogenic differentiation potential and proliferation of HCs were compared among 4 groups. RESULTS: Alkaline phosphatase activity, the expression of osteogenic genes, and the mineralization of HCs in BMP-7 + LIPUS group were shown to be significantly increased compared with the other groups. However, LIPUS did not affect the proliferation of HCs in the presence or absence of BMP-7. CONCLUSIONS: These findings demonstrated for the first time the significant effect of LIPUS on the osteogenic differentiation of HCs in the presence of BMP-7. This study may provide significant evidence for the clinical combined application of BMP-7 and LIPUS for the treatment of acute bone fractures.

Incidence of venous thromboembolism in fractures around and below the knee with physical prophylaxis.

Fractures occurring at the distal part of the lower extremities are recognized to have a relatively lower risk of venous thromboembolism (VTE); however, few detailed reports exist on the subject. The purpose of this study was to investigate the incidence of VTE in fractures around and below the knee. Overall, 109 consecutive patients with fractures around and below the knee who were surgically treated at the authors' hospital were analyzed retrospectively. Physical prophylaxis was performed in all patients. Until April 2009, VTE screening was performed by contrast-enhanced computed tomography or ultrasonography when the D-dimer value did not decline predictably, exceeded 20 µg/mL 5 days after trauma and surgery, or increased above 20 µg/mL after a period of decline. After April 2009, ultrasonography was routinely performed pre- and postoperatively irrespective of the D-dimer value. The patients were divided into 2 groups based on the absence or presence of accompanying injuries, including head, chest, abdominal, or spinal injury and other fractures of the pelvis and lower extremities. Overall, VTE and pulmonary thromboembolism were detected in 28 (25.7%) patients and 5 (4.6%) patients, respectively. All cases were asymptomatic. The VTE incidence rates were 8.6% (former screening) and 40% (newer screening) in patients with isolated fractures and 25% (former screening) and 41.7% (newer screening) in patients with accompanying injuries. The pulmonary thromboembolism incidence rates were 2.9% (former screening) and 0% (newer screening) in patients with isolated fractures and 3.2% (former screening) and 25.0% (newer screening) in patients with accompanying injuries. Surgeons should be vigilant for symptoms of VTE in patients with fractures occurring at the distal part of the lower extremities.

Venous thromboembolism in Japanese patients with fractures of the pelvis and/or lower extremities using physical prophylaxis alone.

PURPOSE: To investigate the rate of venous thromboembolism (VTE) in Japanese patients with fractures of the pelvis and/or lower extremities using physical prophylaxis alone. METHODS: Records of 66 men and 60 women aged 15 to 95 (mean, 57) years with fractures of the pelvis and/ or lower extremities were retrospectively reviewed. They were screened for VTE based on D-dimer values. Contrast-enhanced computed tomography and/or ultrasonography were performed when the D-dimer value did not decline predictably or exceeded 20 µg/ml even 5 days after injury or surgery. Physical prophylaxis for VTE in terms of graduated compression stockings and intermittent pneumatic compression were applied for all patients. RESULTS: Of the 126 patients, 24 were detected to have VTE (10 of 29 with multiple fractures and 14 of 97 with single fractures). Six patients were detected to have asymptomatic pulmonary thromboembolism (PTE), whereas 20 patients were detected to have deep vein thrombosis (bilaterally in 7). The rates of VTE were high in patients with multiple fractures (35%), pelvic fractures (18%), and femoral shaft fractures (50%). The rate of PTE was high in patients with pelvic fractures (12%). CONCLUSION: The rate of VTE in the Japanese patients was similar to that in western populations. Our screening method was useful for preventing fatal PTEs. Surgeons should be vigilant for VTE during the first 2 weeks after injury, especially in patients with multiple and pelvic fractures.

Technique to prepare the bed for autologous bone grafting in nonunion surgery.

This article describes a technique for preparing the bed for autologous bone grafting in nonunion surgery. The procedure is divided into 2 steps. First, both ends of the fracture fragments are chipped into small pieces using an osteotome and hammer without peeling off the periosteum, creating pathways into the bone marrow. Second, cancellous bone harvested from the iliac crest is grafted into the aperture created by the previous bone chipping treatment. The technique is easy to perform and is a promising approach for enhancing bone healing in nonunion and delayed union.

Incidence of venous thromboembolism in pelvic and acetabular fractures in the Japanese population.

BACKGROUND: There are no detailed reports of the incidence of venous thromboembolism (VTE) in pelvic and acetabular fractures in the Asian population. The purpose of this study was to investigate the incidence of VTE in pelvic and acetabular fractures in the Japanese population. METHODS: Forty-six Japanese patients with pelvic and acetabular fractures treated at our hospital from February 2004 to April 2011 were analyzed retrospectively. Until April 2009, VTE screening was performed by contrast-enhanced computed tomography (CT) or ultrasonography (US) when the D-dimer value did not decline predictably, still exceeded 20 µg/ml at 5 days after trauma and surgery, or increased >20 µg/ml after a period of decline. After April 2009, contrast-enhanced CT and US were performed routinely irrespective of the D-dimer value. Physical prophylaxis was performed in all patients. The effects of the presence of pelvic and acetabular fractures, fracture types, accompanying injuries, and screening strategies on the incidences of VTE and pulmonary thromboembolism (PTE) were investigated. RESULTS: Overall, 19 patients (41.3%) were diagnosed with VTE and PTE in ten (21.7%). All were asymptomatic. Compared with trauma patients without pelvic and acetabular fractures treated during the same period, significantly higher incidences of VTE and PTE were observed in patients with pelvic and acetabular fractures. No significant differences were observed in the incidences of VTE and PTE between pelvic and acetabular fractures or between patients with and without accompanying injuries. Compared with the previous screening strategy, the detection rates of VTE and PTE were higher for the newer screening strategy; however, the difference did not reach statistical significance. CONCLUSIONS: We should be vigilant for the high incidence of VTE, especially PTE, in patients with pelvic and acetabular fractures in the Japanese population.

Differential gene expression and immunolocalization of insulin-like growth factors and insulin-like growth factor binding proteins between experimental nonunions and standard healing fractures.

Insulin-like growth factors (IGF-I/II) are important growth factors in bone, and their actions are regulated by six IGF binding proteins (IGFBPs). However, little is known about their exact functions in fracture healing. The aim of this study was to compare the gene expression and immunolocalization of IGFs and IGFBPs between standard healing fractures and nonunions using rat experimental models. Standard healing fractures and nonunions produced by periosteal cauterization at the fracture site were created in rat femurs. At postfracture days 3, 7, 10, 14, 21, and 28, total RNA was extracted from the callus of the healing fractures and the fibrous tissue of the nonunions, and gene expression were analyzed by real-time PCR. Additionally, immunolocalization of these proteins was studied by immunohistochemistry at postfracture days 7, 14, and 21. In nonunions, the gene expression of IGF-I/II and IGFBP-6 was significantly higher, and that of IGFBP-5 was significantly lower at several time points. The immunolocalization of IGF-I/II and IGFBP-5 was widely distributed in both models. In contrast, that of IGFBP-6 was barely detected in the fracture callus. In conclusion, our results suggest that IGFs/IGFBPs may have important roles not only in fracture healing but also in nonunion formation.

Intra-articular injection of tranexamic acid reduces not only blood loss but also knee joint swelling after total knee arthroplasty.

PURPOSE: This is a randomised controlled trial to examine whether intra-articular injection of tranexamic acid (TXA) decreases blood loss, as well as reducing leg swelling after total knee arthroplasty (TKA). METHODS: We performed 100 TKA in osteoarthritis patients. At closure, a total of 2,000 mg/20 ml TXA was injected into the knee joint through a closed suction drain (TXA group). For the control group, the same volume of physiological saline was injected. The pre-operative condition of the patients, post-operative haemoglobin (Hb) levels, discharge volumes from drain, D-dimer and needs for transfusion were compared between these two groups. Furthermore, leg diameters (thigh, suprapatellar portion and calf girth) were measured pre- and post-operatively to investigate whether TXA has an influence on leg swelling after surgery. RESULTS: The results revealed that post-operative decrease in Hb level was significantly reduced in the TXA group. Furthermore, knee joint swelling after operation was significantly suppressed in the TXA group compared to the control group. CONCLUSIONS: The results revealed intra-articular administration of TXA decreased not only blood loss, but also knee joint swelling after TKA.