Shiqiang Cen

Plating versus intramedullary pin or conservative treatment for midshaft fracture of clavicle: a meta-analysis of randomized controlled trials

HYPOTHESIS Clavicular fractures account for 2% to 2.6% of all fractures. Plating has been considered the gold standard for treating midshaft clavicular fracture. Intramedullary pinning and conservative treatments have also been commonly used. We hypothesized that intramedullary pinning and conservative treatments have the same treatment results compared with plating. METHODS To evaluate the effect of plating vs intramedullary pinning or conservative treatment for midshaft clavicular fracture, the Cochrane Central Register of Controlled Trials (CENTRAL; Wiley Online Library, October 2010), PubMed (1950 to October 2010), and EMBASE (1980 to October 2010) were searched. Randomized and quasi-randomized controlled clinical studies evaluating plating vs intramedullary pinning or plating vs conservative treatment for midshaft clavicular fracture in adults were collected. After independent study selection by 2 authors, data were collected and extracted independently. The methodologic quality of the studies was assessed. Pooling of data was undertaken. RESULTS Four studies involving 305 clavicular fractures were included. There were no significant differences between plating and intramedullary pinning with regard to outcome for Oxford Shoulder Score, Constant Shoulder Score, nonunion, infection, fixation failure, and hardware removal. More symptomatic hardware events occurred with plating compared with intramedullary pinning. Reduced nonunion, malunion, and neurologic symptoms, as well as more satisfaction with ultimate appearance, were associated with plating than with conservative treatment. DISCUSSION This meta-analysis supports the treatment effects reported previously with plating for midshaft clavicular fractures. The outcome of this meta-analysis contradicted the findings reported previously with conservative treatment for midshaft clavicular fractures. CONCLUSION The available evidence suggests that there are no differences in treatment effects between plating and intramedullary pinning, but plating is associated with more side effects. Plating is associated with improved treatment effects when compared with conservative treatment.

Coculture of peripheral blood-derived mesenchymal stem cells and endothelial progenitor cells on strontium-doped calcium polyphosphate scaffolds to generate vascularized engineered bone.

Vascularization of engineered bone tissue is critical for ensuring its survival after implantation and it is the primary factor limiting its clinical use. A promising approach is to prevascularize bone grafts in vitro using endothelial progenitor cells (EPC) derived from peripheral blood. Typically, EPC are added together with mesenchymal stem cells (MSC) that differentiate into osteoblasts. One problem with this approach is how to promote traditional tissue engineering bone survival with a minimally invasive method. In this study, we examined the effectiveness of administering to stimulate the release of peripheral blood stem cells and their co-culturing system for generating prevascularized engineered bone. Cells were isolated by Ficoll density gradient centrifugation and identified as EPC and MSC based on morphology, surface markers, and functional analysis. EPC and MSC were cocultured in several different ratios, and cell morphology and tube formation were assessed by microscopy. Expression of osteogenesis and vascularization markers was quantified by enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction, and histochemical and immunofluorescence staining. Increasing the proportion of EPC in the coculture system led to greater tube formation and greater expression of the endothelial cell marker CD31. An EPC:MSC ratio of 75:25 gave the highest expression of osteogenesis and angiogenesis markers. Cocultures adhered to a three-dimensional scaffold of strontium-doped calcium polyphosphate and proliferated well. Our findings show that coculturing peripheral blood-derived EPC and MSC may prove useful for generating prevascularized bone tissue for clinical use.

Tissue Engineering Stratified Scaffolds for Articular Cartilage and Subchondral Bone Defects Repair

Due to their good biocompatibility and mechanical integrity, tissue engineering scaffolds have become a principal method of repair and regeneration of osteochondral defects. To improve their intrinsic properties, control their degenerative times, and enhance their cell adhesion and differentiation, numerous scaffold architectures and formation methods have been developed and tested, but the ideal scaffold design is still controversial. Moreover, scaffold fixation has a significant influence on repair and regeneration after implantation. The authors analyzed relative studies to address the latest scaffold designs, including biphasic scaffold, multilayered scaffold, and continuous nonstratified scaffold, and this article compares their advantages and disadvantages. In addition, the authors introduce a novel modified method for scaffold fixation known as magnetic fixation. Both stratified and nonstratified scaffolds can repair osteochondral defects, but continuous nonstratified scaffolds are more biomimetic compared with the native osteochondral structures, and they lead to a better regeneration of hyaline-like cartilage and structured bone tissue. Therefore, the authors suggest continuous nonstratified scaffolds are an effective option for treating osteochondral defects.

Repair of large osteochondral defects in a beagle model with a novel type I collagen/glycosaminoglycan-porous titanium biphasic scaffold.

The limited repair potential of articular cartilage, which hardly heals after injury or debilitating osteoarthritis, is a clinical challenge. The aim of this work was to develop a novel type I collagen (Col)/glycosaminoglycan (GAGs)-porous titanium biphasic scaffold (CGT) and verify its ability to repair osteochondral defects in an animal model with bone marrow stem cells (bMSCs) in the chondral phase. The biphasic scaffold was composed of Col/GAGs as chondral phasic and porous titanium as subchondral phasic. Twenty-four full-thickness defects through the articular cartilage and into the subchondral bone were prepared by drilling into the surface of the femoral patellar groove. Animals were assigned to one of the three groups: 1) CGT with bMSCs (CGTM), 2) only CGT, and 3) no implantation (control). The defect areas were examined grossly, histologically and by micro-CT. The most satisfied cartilage repairing result was in the CGTM group, while CGT alone was better than the control group. Abundant subchondral bone formation was observed in the CGTM and CGT groups but not the control group. Our findings demonstrate that a composite based on a novel biphasic scaffold combined with bMSCs shows a high potential to repair large osteochondral defects in a canine model.

Cross-arm replantation for traumatic bilateral upper extremity amputations: a case report

A 40-year-old woman had her right extremity avulsed at the proximal upper arm level and the wrist and hand of her left extremity irretrievably injured in a traffic accident. The right distal forearm was surgically amputated and replanted onto the stump of the left distal forearm. New strategy for nerve repair was applied and the function recovery of the cross-replanted hand was favorable. We thought that cross-extremity replantation was indicated when the patient suffered from bilateral total or subtotal amputation at different levels and orthotopic replantation was impossible.

Folded free vascularized fibular grafts for the treatment of subtrochanteric fractures complicated with segmental bone defects.

BACKGROUND: Subtrochanteric fractures of the femur complicated with segmental bone defects are uncommon injuries and challenging to manage. We evaluated the effect of reconstructing extensive bone defect in the subtrochanteric area (mean, 6.9 cm) with folded free vascularized fibular graft (FVFG). METHODS: Between 2001 and 2007, 14 cases of subtrochanteric fractures complicated with huge bone defects treated by folded FVFG transfer in our hospital were retrospectively reviewed. The defect was reconstructed by folded FVFG transfer and locking plate stabilization in 10 patients with no sign of infection at admission (group 1). In the other four patients presented with infections (group 2), the defect was reconstructed by folded FVFG transfer and external fixator fixation. The average follow-up period was 67.4 months. RESULTS: Bone union was achieved in all of the cases at an average of 5.4 months (range, 4–6 months). Primarily, bone union was achieved in all of the cases in group 1, but one stress fracture occurred in group 2. The full weight bearing time was 5.4 months (range, 5–6 months) in group 1 and 8.5 months (range, 8–9 months) in group 2. Seven patients in group 1 had the locking plate removed in an average of 27 months (range, 18–38 months). In group 2, the external fixator removal time was 13 months (range, 10–18 months). There was no varus deformity at the final follow-up in group 1. The neck-shaft angle measured during the postoperative period and at final follow-up was 129.6 degrees and 129.4 degrees, respectively. In group 2, the neck-shaft angle at the final follow-up was significantly less than the angle measured at the postoperative period (115.5 vs. 129.5 degree, p = 0.021). The range of motion of the hip and knee joint (extend and flex) was 100 degrees or more in all patients at the final follow-up. CONCLUSIONS: The results of this study showed that huge subtrochanteric bone defects reconstructed by folded FVFG and locking plate were highly successful in achieving bone union, reducing risks of postoperative stress fracture and preventing malunion. When huge bone defects in the subtrochanteric area complicated with acute or chronic infections, the technique of external fixator offers an alternative to reconstruct the stability of the proximal femur after folded FVFG. However, because of the inadequate stabilization, the risks of varus malunion and postoperative stress fracture could be increased after external fixator fixation. LEVEL OF EVIDENCE: V, therapeutic study.

Massive juxta-articular defects of the distal femur reconstructed by series connected double-strut free-vascularized fibular grafts.

Background: We evaluate the clinical results of reconstructing massive juxta-articular defects of the distal femur (mean, 16.4 cm) with series-connected double-strut free-vascularized fibular grafting (FVFG) and external fixator fixation. Methods: We retrospectively reviewed a consecutive series of 19 patients, who underwent FVFG transfer because of massive juxta-articular defects of distal femur. Sixteen cases had complete records and included in this study. Five patients underwent double-strut FVFG and 11 patients underwent series-connected double-strut FVFG. FVFG was performed from 2 months to 3 months after the clinical signs of the infection had subsided and erythrocyte sedimentation rates had returned to normal. Both fibulas (mean, 18.6 cm) were harvested to reconstruct the femoral defect, half-ring sulcated external fixator (Orthofix Srl, Italy), and K-wires were used to provide stabilization. Results: Five fibular grafts (15.6%) had vascular complications on flap monitoring. Fifteen of the sixteen reconstructed femurs (93.8%) united primarily. Stress fracture occurred in one patient. The mean duration to achieve union was 7.1 month (range, 4–18 months). Full weight-bearing walking was allowed 3 months after the confirmation of bone union (mean, 10 months; range, 7–22 months). The external fixator was removed 12.2 months (range, 10–16 months) postoperatively. The K-wires were removed 26.4 months (range, 23–30 months) postoperatively. There was no statistically significant difference of hypertrophic change between series-connected grafts and conventional double-strut grafts (27.18 vs. 24.43%, p = 0.186) and also between the three levels of the grafted fibula. Within the series-connected group, the difference of hypertrophic change between anterograde fibular grafts and retrograde fibular grafts was also not significant (25.24 vs. 29.12%, p = 0.178). The overall rate of knee stiffness (<90 degree) was as high as 68.75% (11 of 16 patients). Conclusions: Massive juxta-articular defects of the distal femur are difficult and uncommon injuries. The results of this study indicate that the huge femoral defect reconstructed by series-connected double-strut FVFG provide good results in achieving bone union, reducing stress fracture rate, and achieving leg length equality.

Combination of granulocyte colony-stimulating factor and CXCR4 antagonist AMD3100 for effective harvest of endothelial progenitor cells from peripheral blood and in vitro formation of primitive endothelial networks

Endothelial progenitor cells (EPC) derived from the circulation may be used to enhance neovascularization. Since the combination of granulocyte colony-stimulating factor (GCSF) and CXCR4 antagonist AMD3100 efficiently mobilizes hematopoietic stem cells into peripheral circulation, it may increase the pool of endogenously circulating EPC. We tested this hypothesis by administering GCSF and AMD3100 to adult rabbits and rats, isolating mononuclear cells from peripheral blood by Ficoll density gradient centrifugation, and characterizing the blood-derived EPC based on morphology, immunophenotyping, gene expression and other functional analyses. These EPC showed clonal growth similar to that of human umbilical vein endothelial cells when cultured in complete EGM-2 medium on collagen I-precoated culture plates. The EPC exhibited a typical cobblestone-like morphology and were relatively homogeneous by the third passage. The cells expressed the typical endothelial marker CD31 based on flow cytometry and fluorescence microscopy, formed capillary-like structures when cultured in Matrigel, internalized DiI-acetylated low-density lipoprotein, bound Ulex europaeus agglutinin-1, and expressed CD31 and several other endothelial markers (VEGFR2, VE-cadherin, Tie-2, eNOS, vWF) at significantly higher levels than bone marrow-derived mesenchymal stem cells. These results suggest that the combination of GCSF and AMD3100 can efficiently release stem cells into peripheral circulation and generate EPC that show the desired morphological, immunophenotypic and functional characteristics. This minimally invasive approach may be useful for autologous cell transplantation for postnatal neovasculogenesis and tissue repair.

Appropriate excision time of heterotopic ossification in elbow caused by trauma

Objective The aim of this study was to investigate the optimal timing for the resection of heterotopic ossification (HO) of the elbow. Methods We retrospectively reviewed 42 patients who were treated operatively for heterotopic ossification of the elbow from March 2010 to December 2014 at our institution. The patients were divided into early (before 12 months) and late (after 12 months) excision groups. In the early excision group (17 patients), the average time from the initial injury to HO excision was 7.4 (3–11) months, and in the late excision group (25 patients), the average time was 33.5 (12–240) months. Every patient was evaluated by range of motion (ROM), the Mayo Elbow Performance Score (MEPS), postoperative complications and HO recurrence. Results The preoperative mean ROM in the late excision group was greater than that of the early excision group, suggesting that the ROM is expected to increase even without surgery. Both early and late surgery increased ROM and MEPS, but early surgery improved ROM and MEPS more than late surgery did (p < .05). Conclusions Early excision of HO can provide better elbow function, as indicated by ROM and MEPS. Considering that there were no notable differences in postoperative ROM and MEPS, HO recurrence, or postoperative complications, we concluded that early excision is safe and that the time from an elbow injury to surgery may be shortened. Level of Evidence Level III, therapeutic study.

Treatment of Compartment Syndrome of the Thigh Associated With Acute Renal Failure After the Wenchuan Earthquake

Compartment syndrome of the thigh is a rare emergency often treated operatively. The purpose of this study was to evaluate the effects of nonoperative treatment for compartment syndrome of the thigh associated with acute renal failure after the 2008 Wenchuan earthquake. Nonoperative treatment, which primarily involves continuous renal replacement therapy, was performed in 6 patients (3 men and 3 women) who presented with compartment syndrome of the thigh associated with acute renal failure. The mean mangled extremity severity score (MESS) and laboratory data regarding renal function were analyzed before and after treatment, and the clinical outcome was evaluated at 17-month follow-up. Laboratory data regarding renal function showed improvements. All 6 patients survived with the affected lower limbs intact after nonoperative treatment. Follow-up revealed active knee range of motion and increased muscle strength, as well as a recovery of sensation. A positive linear correlation was found between MESS and the time required to achieve a reduction in swelling, as well as the time required for the recovery of sensation and knee range of motion (r>0.8; P<.05). Satisfactory clinical outcomes were obtained in patients with compartment syndrome of the thigh associated with acute renal failure.Urine alkalization, electrolyte and water balance, and continuous renal replacement therapy have played an important role in saving lives and extremities. Nonoperative treatment should be considered in the treatment of compartment syndrome of the thigh associated with acute renal failure.