Efficacy comparison of vascularized iliac crest bone flap and Ilizarov bone transport in the treatment of traumatic bone defects of the tibia combined with large soft tissue defects.

BACKGROUND: Traumatic tibial defect complicated with soft tissue defect is a difficult problem in clinic. Vascularized iliac crest bone flap (VIBF) and Ilizarov bone transport are effective methods to treat tibial defects with limited defect length, which most need to be explored accordingly. METHODS: In this study, a total of 68 patients with traumatic tibial defect (ranging from 4 to 10 cm) and large soft tissue defect were collected retrospectively. The soft tissue defects were repaired by latissimus dorsal musculocutaneous flap (LD), anterolateral thigh flap (ALTF) or both. Thirty-three cases were treated with vascularized iliac crest bone flap transplantation and 35 cases were treated with Ilizarov bone transport. Intraoperative and postoperative follow-up data (including operation time, blood loss, bone union time, external fixation time, external fixation index, complication rate, reoperation rate, and functional evaluation) were recorded, and comparative analysis was performed. RESULTS: The median follow-up time was 32 months. Compared with Ilizarov group, the VIBF group exhibited statistically faster bone union time (6.3 ± 1.0 vs. 18.2 ± 3.0 months). Moreover, the VIBF group showed shorter EFT (7.3 ± 1.0 vs. 19.2 ± 3.0 months) and a better EFI (34.8 ± 9.2 vs. 84.2 ± 23.7 days/cm). The excellent and good rate of lower limb appearance evaluation in VIBP group was significantly better than that in Ilizarov group. The complication rate and reoperation rate were significantly higher in Ilizarov group. CONCLUSION: In summary, compared with Ilizarov bone transport, VIBP has the advantages of faster healing, shorter external fixation time, lower complication and reoperation rate, and better appearance within the limited defect length. Ilizarov bone transport is still preferred when the defect length exceeds the maximum repair length of the iliac flap. The daily handling required by bone transport process is painful. LEVEL OF EVIDENCE: III, Case-control study.

Pedicled iliac bone flap grafting in the treatment of late presentation Legg-Calvé-Perthes disease.

Background: Legg-Calvé-Perthes disease (LCPD) is a juvenile form of ischemic femoral head osteonecrosis affecting children. The lack of effective and timely treatment results in severe sequelae in children (especially older ones). Although LCPD has been widely studied, little is known about its etiology. As a result, its clinical management is still challenging. This study will investigate the clinical and radiological results of patients older than 6 years and treated with pedicled iliac bone flap grafting for LCPD. Materials and methods: A total of 13 patients (13 hips) with late presentation of LCPD were treated with pedicled iliac bone flap grafting. Of the 13 patients, 11 were male and 2 were female. The average age of the patients was 8.4 years (range 6-13). Preoperational radiographs and pain scores were analyzed for lateral pillar classification and the Oucher scale. The final follow-up radiograph was classified using a modified Stulberg classification. Limping, extremity length inequality, and range of motion were clinically assessed. Results: The average follow-up of the patients was 70 months (range 46-120). During the surgery, seven hips were found to be lateral pillar grade B, two were grade B/C, and four were grade C. In the final examination, 12 hips were evaluated as good (Stulberg class I or II) and one as medium (Stulberg class III). There was limb shortening in one patient who was Stulberg class III. There was a significant difference between the preoperational and postoperational radiographic values and the Ocher scale, regardless of the surgical staging (P < 0.05). Conclusions: Pedicled iliac bone flap graft can treat LCPD accompanied by pain and lateral pillar stage B, B/C, and C in children over 6 years. Level of Evidence: Level IV-case series.

Extracellular vesicles from human urine-derived stem cells inhibit glucocorticoid-induced osteonecrosis of the femoral head by transporting and releasing pro-angiogenic DMBT1 and anti-apoptotic TIMP1.

Osteonecrosis of the femoral head (ONFH) frequently occurs after glucocorticoid (GC) treatment. Extracellular vesicles (EVs) are important nano-sized paracrine mediators of intercellular crosstalk. This study aimed to determine whether EVs from human urine-derived stem cells (USC-EVs) could protect against GC-induced ONFH and focused on the impacts of USC-EVs on angiogenesis and apoptosis to explore the mechanism by which USC-EVs attenuated GC-induced ONFH. The results in vivo showed that the intravenous administration of USC-EVs at the early stage of GC exposure could rescue angiogenesis impairment, reduce apoptosis of trabecular bone and marrow cells, prevent trabecular bone destruction and improve bone microarchitecture in the femoral heads of rats. In vitro, USC-EVs reversed the GC-induced suppression of endothelial angiogenesis and activation of apoptosis. Deleted in malignant brain tumors 1 (DMBT1) and tissue inhibitor of metalloproteinases 1 (TIMP1) proteins were enriched in USC-EVs and essential for the USC-EVs-induced pro-angiogenic and anti-apoptotic effects in GC-treated cells, respectively. Knockdown of TIMP1 attenuated the protective effects of USC-EVs against GC-induced ONFH. Our study suggests that USC-EVs are a promising nano-sized agent for the prevention of GC-induced ONFH by delivering pro-angiogenic DMBT1 and anti-apoptotic TIMP1. STATEMENT OF SIGNIFICANCE: This study demonstrates that the intravenous injection of extracellular vesicles from human urine-derived stem cells (USC-EVs) at the early stage of glucocorticoid (GC) exposure efficiently protects the rats from the GC-induced osteonecrosis of the femoral head (ONFH). Moreover, this study identifies that the promotion of angiogenesis and inhibition of apoptosis by transferring pro-angiogenic DMBT1 and anti-apoptotic TIMP1 proteins contribute importantly to the USC-EVs-induced protective effects against GC-induced ONFH. This study suggests the promising prospect of USC-EVs as a new nano-sized agent for protecting against GC-induced ONFH, and the potential of DMBT1 and TIMP1 as the molecular targets for further augmenting the protective function of USC-EVs.

Reconstructive surgery for foot and ankle defects in pediatric patients: Comparison between anterolateral thigh perforator flaps and deep inferior epigastric perforator flaps.

BACKGROUNDS: Due to the delicate tissue, small blood vessels and incomplete development of interarticular ligaments, skin and soft-tissue defects of the foot and ankle in pediatric patients remain a challenge for orthopedic and plastic surgeons. Anterolateral thigh perforator (ALTP) flap and deep inferior epigastric perforator (DIEP) flap are the most commonly used flaps for the repair of lower-extremity soft-tissue defects. The literature contains a shortage of evidence involving the differences between ALTP and DIEP flaps in the reconstruction of young patients with complex foot and ankle defects. This study was designed to determine which type of flap is better for foot and ankle repair in pediatric patients. METHODS: From January 2004 to January 2018, 79 children younger than 14 years treated with DIEP flap (41 cases) or ALTP flap (38 cases) for composite defects of the feet and ankles were retrospectively investigated. The two groups were homogeneous in terms of age, the location of the defect, etiology, and flap area. Complications, scarring, cosmetic appearance, flap sensory recovery, and functional outcome were analyzed, and statistical analysis was performed. RESULTS: The ALTP group had shorter operation time (155.0 ±â€¯12.0 min vs 212.2 ±â€¯23.9 min), flap harvested time (39.6 ±â€¯5.1 min vs 57.2 ±â€¯10.4 min), and operative blood loss (143.4 ±â€¯23.7 ml vs 170.7 ±â€¯44.7 ml) than the DIEP group (P <  0.05). In short-term follow-up, ALTP group showed a lower flap necrosis rate (5.3% vs 24.4%) and vascular insufficiency rate (2.6% vs 19.5%) than DIEP group (P <  0.05). In long-term follow-up, ALTP group showed a lower late complication rate and better cosmetic, functional, scar outcomes than DIEP group (P <  0.05). CONCLUSIONS: The study showed that an ALTP flap may brings better results than a DIEP flap in terms of short- and long-term complications, scarring, and morpho-functional outcomes for pediatric patients undergoing reconstruction of foot and ankle defects.

Systemic and flap inflammatory response associates with thrombosis in flap venous crisis.

Venous crisis represents the most common complication in flap surgery and often results in flap failure. The gold standard for free flap monitoring is frequent clinical examination. The current study examined the systemic inflammatory response during the immediate post-operative period following flap venous crisis. Superficial epigastric artery perforator flap transplantation was performed in a total of 30 rabbits. Fifteen animals received venous obstruction by vein ligation (venous crisis group, n = 15) and others were sham treated (control group, n = 15). Venous thrombosis was examined by immunohistochemistry staining. Plasma levels of inflammatory response markers (IL-6, IL-8, TNF-α, and C-reactive protein) and thrombosis biomarkers (von Willebrand factor and tissue factor) were measured at 0, 2, and 4 h post-operation by enzyme-linked immunosorbent assay. The mRNA levels of relevant biomarkers in the flap were analyzed with quantitative real-time PCR. Flap histopathological examination showed erythrocyte and neutrophil aggregations in venous lumen and erythrocyte diapedesis. At 8 h post-operation, serious edema and fibrinoid necrosis were observed and the venous lumen was almost blocked by thrombus. The venous crisis group had higher plasma levels of IL-8, TNF-α, and thrombosis biomarkers. Vein ligation also increased the mRNA levels of IL-8, TNF-α, C-reactive protein, von Willebrand factor, and tissue factor in the flap. No significant change in IL-6 levels was observed between the control group and the venous crisis group. Flap venous crisis was accompanied by the increase in a number of inflammatory and thrombosis markers, both in the peripheral blood and the flaps.

[The clinic application of thoracodorsal artery perforator flap: a report of 16 cases].

OBJECTIVE: To investigate the effects of free and pedicled thoracodorsal artery perforator (TDAP) flaps for repairing skin and soft tissue defects in limbs, neck, axillary and shoulder. METHODS: From October 2009 to Auguest 2011, 16 TDAP flaps were used to repair skin and tissue defects. Among them, five ipsilateral pedicled flaps were used to repair wounds in neck, axillary and shoulder. 11 free TDAP flaps were used to repair the wounds with bone or tendon exposure. In 12 cases, the flaps were pedicled with thoracodorsal artery and vein-lateral branches-perforators, in 4 cases, pedicled with thoracodorsal artery and vein-serratus anterior muscular branches-perforators. The deep fascia, the latissimus dorsi and thoracodorsal nerve were not included in all flaps. The flaps size ranged from 10 cm x 5 cm to 26 cm x 10 cm. RESULTS: All 16 flaps survived completely with primary healing both at donor site and recipent area. After a follow-up of 3 to 24 months, all flaps gained good texture and appearance. Only linear scar was left at donor area. The shoulder could move freely. CONCLUSIONS: TDAP flap has good texture, long vascular pedicle,and reliable blood supply, leaving less morbidity at donor site. The latissimus dorsi and thoracodorsal nerve are also preserved. The pedicled TDAP flap is an ideal flap for repairing the ipsilateral skin and soft tissue defects of the neck, shoulder, axillary. The free TDAP flap is suited for repairing skin and soft tissue defects of the extremities.