Stimulation of Nitric Oxide Production Contributes to the Antithrombotic Effect of Stromal Cell-Derived Factor-1α in Preventing Microsurgical Anastomotic Thrombosis.

Background Intimal injury plays a critical role in initiating the pathogenesis of thrombosis formation after microsurgical anastomosis. Application of stromal cell-derived factor-1α (SDF-1α) is reported to promote early regeneration of injured intima through migration of endothelial cells and mobilization of endothelial progenitor cells. We therefore hypothesized that local transfer of SDF-1α gene would inhibit microsurgical anastomotic thrombosis. Methods Sixty Sprague-Dawley rats were used and divided randomly into three groups (SDF-1α group, plasmid group, and saline group) in this study. Plasmid DNA encoding SDF-1α, empty plasmid, and saline were injected into the left femoral muscles of rats from each group, respectively. Seven days after injection, peripheral blood samples were obtained to measure the plasma levels of SDF-1α and nitric oxide (NO). The left femoral artery of each rat was crushed, transected, and repaired by end-to-end microsurgical anastomosis. Vascular patency was assessed at 15, 30, and 120 minutes after reperfusion using milk test. Thrombosis formation was assessed with hematoxylin and eosin staining and scanning electron microscopy at 120 minutes postoperatively. Results The plasma levels of SDF-1α and NO in SDF-1α group were significantly higher than those in plasmid group and saline group (p < 0.01). The patency rate in SDF-1α group was significantly higher than that in control groups at 120 minutes after reperfusion (p < 0.05). Treatment of SDF-1α significantly reduced the size of thrombotic occlusion when compared with controls (p < 0.05). All SDF-1α recipients exhibited decreased thrombosis under scanning electron microscopy. Conclusions The current study demonstrated that local transfer of SDF-1α gene increases arterial patency and inhibits microsurgical anastomotic thrombosis in a crush model of femoral artery in rat. The antithrombotic effect of SDF-1α may be mediated through increased production of endogenous NO. These findings provide a novel approach for inhibition of microsurgical anastomotic thrombosis.

Developmental pattern of the hip in patients with hereditary multiple exostoses.

BACKGROUND: Coxa valga is a common clinical feature of hereditary multiple exostoses (HME). The current study aimed to determine the unique developmental pattern of the hip in patients with HME and evaluate the factors that influence its progression. METHODS: Thirty patients (57 hips) with HME were divided into two groups according to the Hilgenreiner epiphyseal angle (HEA). Twenty-two patients (44 hips) including 13 men and 9 women were assigned to group 1 (HEA <25°), and 8 patients (13 hips) including 3 men and 5 women were assigned to group 2 (HEA ≥25°). The mean age at the initial presentation was 6.0 (4-12) years with 6.8 (4-11) years of follow-up in group 1, and 10.4 (8-13) years with 5.4 (2-9) years of follow-up in group 2. We measured the HEA, neck-shaft angle (NSA), acetabular index (AI), center-edge angle (CEA), and migration percentage (MP) for radiographic evaluation. RESULTS: Among the hips, 50 (87.7%) hips had coxa valga and 27 (47.4%) hips had abnormal MP (42.1% were borderline and 5.3% were subluxated). There was a significant difference in the HEA and NSA between the groups (p < 0.001 and p < 0.05, respectively). The HEA significantly correlated with the development of the NSA and no correlation was found between the HEA and AI, CEA, and MP. CONCLUSIONS: There was a significant relationship between the HEA at the initial presentation and the NSA at skeletal maturity. We should consider guided growth for patients with lower HEA to prevent significant coxa valga deformity with close follow-up.

Combined Anterolateral Thigh and Anteromedial Thigh Flap for Extensive Extremity Reconstruction: Vascular Anatomy and Clinical Application.

BACKGROUND: The combined anterolateral thigh (ALT) and anteromedial thigh (AMT) flap has been previously reported for use in complicated head and neck reconstruction. However, it has not gained popularity due to the vascular variation. Here, we explore the vascular basis of this combined flap, and report its application in extremity reconstruction. METHODS: This study was divided into two parts: vascular anatomy and clinical application. In the anatomical study, 52 sides of adult thighs were dissected to identity vascular perforators supplying the combined ALT and AMT flap, with focus on sizeable perforators (larger than 0.5 mm) arising from the descending branch of the lateral circumflex femoral artery.Clinically, five male patients were treated by combined ALT and AMT flaps for extensive extremity reconstruction from January 2006 to December 2010. The mean age was 32 years (range, 23-45 years). The combined flap was used for covering large soft-tissue defects in forearm (n = 3) and calf (n = 2). For each patient, esthetic and functional results were recorded. RESULTS: The anatomical study showed that sizeable perforators supplying the ALT flap were present in 50 thighs (96.2%), and the perforators supplying the AMT flap were present in 32 thighs (61.5%). The combined ALT and AMT flaps were available in 30 thighs (57.7%).All five combined flaps survived completely. Skin grafts covering the donor sites healed uneventful. The mean follow-up was 9.6 months (range, 6-12 months). No complications were recorded during the follow-up. CONCLUSION: The combined ALT and AMT flap may be used for extensive extremity reconstruction in selected patients for its great maneuverability and acceptable donor-site morbidity.

How reliable are standard radiographic measures of the foot and ankle in children with achondroplasia?

BACKGROUND: Radiographic measurements are typically used in achondroplasia (ACH) during correction of lower limb alignment. However, reliabilities for the measurements on weightbearing radiographs of the foot and ankle in patients with ACH have not been described, and the differences between the ACH population and subjects without ACH likewise have not been well characterized; these issues limit the use of studies on this subject. QUESTIONS/PURPOSES: We proposed (1) to measure the inter- and intraobserver reliability of a number of radiographic measures of ankle and foot alignment in an achondroplastic cohort of patients; and (2) to compare our radiographic measurement values with age-matched literature-based normative values. METHODS: Ten radiographic measurements were applied to foot and ankle radiographs of 20 children (40 feet) with ACH (mean age, 10 years; range, 8-16 years). Interobserver and intraobserver reliabilities of these radiographic measurement methods were obtained and expressed by intraclass correlation coefficients (ICCs). The mean values were calculated and compared with the literature-based values. RESULTS: The interobserver reliability was excellent for eight measurements with ICCs ranging from 0.801 to 0.962, except for lateral talo-first metatarsal angle and mediolateral column ratio, which were much lower. The intraobserver reliability was excellent for all 10 radiographic measurements with ICCs ranging from 0.812 to 0.998. Compared with existing literature-based values, all 10 measurements had a significant difference (p < 0.01). CONCLUSIONS: We suggest tibiotalar angle, calcaneal pitch angle, tibiocalcaneal angle, talocalcaneal angle, naviculocuboid overlap, talonavicular coverage angle, metatarsal stacking angle, and AP talo-first metatarsal angle with excellent interobserver and intraobserver reliabilities should be considered preferentially in analysis of foot and ankle alignment in children with ACH.

Distal Ulnar Bifurcation Arthroplasty in the Treatment of Bayne and Klug Types 3 and 4 Radial Club Hands: Preliminary Outcomes.

BACKGROUND: The treatment of Bayne and Klug types 3 and 4 radial club hands (RCHs) remains challenging and controversial. In this study, the authors reported a new procedure called distal ulnar bifurcation arthroplasty and reviewed the preliminary results. METHODS: Between 2015 and 2019, 11 patients with 15 affected forearms having type 3 or 4 RCHs underwent distal ulnar bifurcation arthroplasty. The mean age was 55.5 months (range, 29 to 86 months). The surgical protocol consisted of (1) bifurcation of the distal ulna to accommodate the wrist with stable support; (2) pollicization to treat hypoplastic or absent thumb; and (3) in the case of significant bowed ulna, ulnar corrective osteotomy. In all patients, clinical and radiologic parameters including hand-forearm angle, hand-forearm position, ulnar length, wrist stability, and motion were recorded. RESULTS: The mean duration of follow-up was 42.2 months (range, 24 to 60 months). The average correction of hand-forearm angle was 80.2 degrees. The overall range of active wrist motion was approximately 87.5 degrees. Ulna growth per year was 6.7 mm (range, 5.2 to 9.2 mm). No major complications were recorded during follow-up. CONCLUSIONS: The distal ulnar bifurcation arthroplasty offers a technically feasible alternative for the treatment of type 3 or 4 RCH, which enables satisfactory appearance, provides stable support to the wrist, and maintains wrist function. Despite the promising preliminary results, longer follow-up is necessary to evaluate this procedure. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

LncAABR07053481 inhibits bone marrow mesenchymal stem cell apoptosis and promotes repair following steroid-induced avascular necrosis.

The osteonecrotic area of steroid-induced avascular necrosis of the femoral head (SANFH) is a hypoxic microenvironment that leads to apoptosis of transplanted bone marrow mesenchymal stem cells (BMSCs). However, the underlying mechanism remains unclear. Here, we explore the mechanism of hypoxic-induced apoptosis of BMSCs, and use the mechanism to improve the transplantation efficacy of BMSCs. Our results show that the long non-coding RNA AABR07053481 (LncAABR07053481) is downregulated in BMSCs and closely related to the degree of hypoxia. Overexpression of LncAABR07053481 could increase the survival rate of BMSCs. Further exploration of the downstream target gene indicates that LncAABR07053481 acts as a molecular "sponge" of miR-664-2-5p to relieve the silencing effect of miR-664-2-5p on the target gene Notch1. Importantly, the survival rate of BMSCs overexpressing LncAABR07053481 is significantly improved after transplantation, and the repair effect of BMSCs in the osteonecrotic area is also improved. This study reveal the mechanism by which LncAABR07053481 inhibits hypoxia-induced apoptosis of BMSCs by regulating the miR-664-2-5p/Notch1 pathway and its therapeutic effect on SANFH.

Three novel PHEX gene mutations in four Chinese families with X-linked dominant hypophosphatemic rickets.

BACKGROUND: X-linked hypophosphatemia (XLH), the most common form of inherited rickets, is a dominant disorder that is characterized by renal phosphate wasting with hypophosphatemia, abnormal bone mineralization, short stature, and rachitic manifestations. The related gene with inactivating mutations associated with XLH has been identified as PHEX, which is a phosphate-regulating gene with homologies to endopeptidases on the X chromosome. In this study, a variety of PHEX mutations were identified in four Chinese families with XLH. METHODS: We investigated four unrelated Chinese families who exhibited typical features of XLH by using PCR to analyze mutations that were then sequenced. The laboratory and radiological investigations were conducted simultaneously. RESULTS: Three novel mutations were found in these four families: one frameshift mutation, c.2033dupT in exon 20, resulting in p.T679H; one nonsense mutation, c.1294A>T in exon 11, resulting in p.K432X; and one missense mutation, c.2192T>C in exon 22, resulting in p.F731S. CONCLUSIONS: We found that the PHEX gene mutations were responsible for XLH in these Chinese families. Our findings are useful for understanding the genetic basis of Chinese patients with XLH.

Peroneal artery perforator chimeric flap for reconstruction of composite defects in extremities.

Large bone defects of extremities, especially those associated with soft tissue defects, represent difficult reconstructive problems. Chimeric flap is a suitable option for reconstruction of complex bone and soft-tissue defects. In this report, we present the experience on use of the peroneal artery perforator chimeric flap for the reconstruction of complex bone and soft tissue defects in the extremities in 16 patients. The bone defects were located in the tibia in 8 patients, in both tibia and fibula in 1 patient, in the ulna in 2 patients, in both ulna and radius in 2 patients, and the metatarsal bone in 3 patients. The flap was created with skin paddle and fibula bone segments based on independent perforators. The sizes of flap ranged from 8 x 6 to 20 x 11 cm(2), and the length of fibular grafts ranged from 6 to 22 cm. All flaps survived completely. Bone union was ultimately obtained in all cases at 5 to 11 months, while two cases suffered from stress fractures in 12 month and 18 month after operation, respectively, which eventually healed with external fixation treatment. The follow-up time ranged from 12 to 37 months. The definite bone hypertrophy was observed from X-ray at 18 months after operation. In conclusion, our results show that the peroneal artery perforator chimeric flap is a good option for reconstruction of complex bone and soft-tissue defects of extremities, particularly for those with three-dimensional defects and bone defects exceeding 6 cm in length.

Docosahexaenoic Acid Improves Diabetic Wound Healing in a Rat Model by Restoring Impaired Plasticity of Macrophage Progenitor Cells.

BACKGROUND: Chronic inflammation associated with delayed diabetic wound healing is induced by disturbed polarization of macrophages derived mainly from predisposed progenitor cells in bone marrow. Docosahexaenoic acid plays a critical role in regulating the function of macrophage progenitor cells. The authors evaluated whether docosahexaenoic acid accelerates diabetic wound healing in rats. METHODS: Streptozotocin-induced diabetic rats divided into control and docosahexaenoic acid-treated groups (n = 10) were subjected to paired dorsal skin wounds. Docosahexaenoic acid (100 mg/kg per day) was orally supplemented 2 weeks before wounding until termination. The wound healing process was recorded 0, 7, and 14 days after wounding. At day 7, blood perfusion was measured by laser Doppler perfusion imaging; angiogenesis was compared using immunofluorescent CD31 and α-smooth muscle actin staining; macrophage polarization was detected using immunofluorescence for CD68, CD206, and inducible nitric oxide synthase. Hematoxylin and eosin staining was used to examine wound healing at day 14. Activation status of macrophages derived from bone marrow cells in normal, diabetic, and docosahexaenoic acid-treated diabetic rats was determined in vitro using Western blotting and enzyme-linked immunosorbent assay. RESULTS: Docosahexaenoic acid significantly accelerated wound healing 7 and 14 days (p < 0.01) after wounding. Increased vessel densities (1.96-fold; p < 0.001) and blood perfusion (2.56-fold; p < 0.001) were observed in docosahexaenoic acid-treated wounds. Immunofluorescence revealed more CD206 and fewer inducible nitric oxide synthase-positive macrophages (p < 0.001) in treated wounds. Furthermore, macrophages derived from diabetic rats expressed higher levels of inducible nitric oxide synthase and tumor necrosis factor-α and lower arginase-1 and interleukin-10 (p < 0.05). CONCLUSION: Docosahexaenoic acid accelerates diabetic wound healing at least in part by restoring impaired plasticity of macrophage progenitor cells.

Identification of a novel pathogenic mutation of the MYH3 gene in a family with distal arthrogryposis type 2B.

Distal arthrogryposis (DA) type 2B (DA2B) is an autosomal dominant congenital disorder, characterized by camptodactyly, thumb adduction, ulnar deviation and facial features, including small mouth, down­slanting palpebral fissure and slight nasolabial fold. It has been reported that four genes are associated with DA2B, including troponin I, fast­twitch skeletal muscle isoform, troponin T3, fast skeletal, myosin heavy chain 3 (MYH3) and tropomyosin 2, which are all associated with embryonic limb morphogenesis and skeletal muscle contraction. In the present study, three affected family members and five unaffected individuals were identified through clinical and radiological assessment. Genomic DNA was obtained from the three patients, which then underwent whole­exome sequencing, and candidate mutations were verified by Sanger sequencing in all available family members and 100 healthy volunteers. Then, the spatial models of embryonic MYH were further constructed. In the clinic, the three patients recruited to the present study were diagnosed with DA2B. Mutation analysis indicated that there was a novel heterogeneous missense mutation c.2506 A>G (p.K836E) in the MYH3 gene among the affected individuals, which was highly conserved and was not identified in the unaffected family members and healthy controls. Furthermore, protein modeling revealed that the altered position interacted with regulatory light chain. Thus, the present study identified a novel pathogenic mutation of the MYH3 gene in a Chinese family with DA2B, which expanded the mutational spectrum of MYH3 and provided additional information regarding the association between mutation locations and different types of DA.

A MYH3 mutation identified for the first time in a Chinese family with Sheldon-Hall syndrome (DA2B).

Sheldon-Hall syndrome is the most common type of distal arthrogryposis syndromes, also known as distal arthrogryposis 2B (DA2B). Sheldon-Hall syndrome is caused by mutations in the TPM2, TNNI2, TNNT3 or MYH3 gene and characterized by ulnar deviation, camptodactyly, overlapping fingers and scoliosis from birth. We investigated a Chinese family with multiple members who clinically presented with distal arthrogryposis of the hands. In total, 261 subjects including one proband and ten family members from the non-consanguineous Chinese family and 250 healthy volunteers were included and had their genomic DNA extracted. A novel missense mutation in exon 13 of the MYH3 gene, c.1160A > G (p.Tyr387Cys), was identified in the proband and his father through whole-exome sequencing. The proband and six affected family members were confirmed to carry this mutation by Sanger sequencing, although the mutation was not detected in the four unaffected individuals or 250 volunteers. This is the first report of a novel MYH3 mutation being identified as the cause of DA2B in a Chinese family. Our findings confirm that MYH3 gene mutations can be a pathogenic cause of DA2B in Asian patients. This study increases the mutational spectrum in MYH3 and aids genetic counseling and prenatal diagnosis.

Identification of a novel mutation of the NTRK1 gene in patients with congenital insensitivity to pain with anhidrosis (CIPA).

INTRODUCTION: Congenital insensitivity to pain with anhidrosis (CIPA) is a rare autosomal recessive disorder resulting from NTRK1 mutation. Over 105 NTRK1 mutations have been reported in CIPA patients worldwide. The causative NTRK1 mutations lead to loss of function of the TrkA protein, an important ligand for nerve growth factor (NGF), and therefore induce various clinical phenotypes associated with neuron maturation defects. MATERIALS AND METHODS: Three patients from unrelated families with CIPA were subjected to detailed clinical examinations. Blood samples were collected from all the patients and their available family members, as well as 200 healthy volunteers. Sanger sequencing for all the exons and splicing sites of NTRK1 was performed on all samples. The phenotype-genotype relationship and genetic epidemiology of Chinese CIPA patients were also analysed. RESULTS: A total of four different NTRK1 mutations [c.851-33T>A, c.44G>A (p.Trp15*), c.287+2dupT, c.1549G>C (p.Gly517Arg)] were identified in these families, and c.1549G>C (p.Gly517Arg) was a novel mutation that had not been reported previously. The 'mild' manifestations observed in patients with c.851-33T>A indicated this mutation as a 'mild' mutation. After reviewing studies reporting mutations in Chinese CIPA patients, we speculate the mutation c.851-33T>A is one of the founder mutations in the Chinese population. CONCLUSIONS: Our research expanded the spectrum of the NTRK1 mutations associated with CIPA patients, provided additional clues relating to the phenotype-genotype relationship in CIPA, and summarized the features of the genetic epidemiology of CIPA in the Chinese ethnic group.

A novel duplication downstream of BMP2 in a Chinese family with Brachydactyly type A2 (BDA2).

BACKGROUND: Brachydactyly type A2 (BDA2) is an autosomal dominant disease characterized by the deformation of the middle phalanx of the second fingers and toes. It has been reported to be associated with three genes regulating the osteogenesis, including BMPR1B, GDF5 and BMP2. MATERIALS AND METHODS: 10 BDA2 patients and 7 unaffected individuals in a Chinese family were identified through clinical signs and radiographs. The mutation analyses of BMPR1B, GDF5 and BMP2 gene was performed in all the available family members and 100 control subjects. The duplication analysis for the downstream of BMP2 was also performed in all the samples. RESULTS: A novel 4671bp duplication downstream the BMP2 gene was identified in all the patients undergoing molecular analysis but not in the unaffected individuals and healthy controls, with a 28bp microhomology flanking it. There was no mutation in all the exons of BMPR1B, GDF5 and BMP2 in all the tested family members. CONCLUSION: The novel duplication has different breakpoints compared with the previous ones but highly overlapped with them. The duplication narrows the range of the potential cis-regulatory sequence, and further supports the association between BDA2 and the duplication downstream BMP2.

Postaxial limb hypoplasia (PALH): the classification, clinical features, and related developmental biology.

Postaxial limb hypoplasia (PALH) is a group of nonhereditary diseases with congenital lower limb deficiency affecting the fibular ray, including fibular hemimelia, proximal femoral focal deficiency, and tarsal coalition. The etiology and the developmental biology of the anomaly are still not fully understood. Here, we review the previous classification systems, present the clinical features, and discuss the developmental biology of PALH.

The Effect of Atorvastatin on the Viability of Ischemic Skin Flaps in Diabetic Rats.

BACKGROUND: Endothelial progenitor cells play a critical role in neovascularization. However, the mobilization, recruitment, and functional capacity of endothelial progenitor cells are significantly impaired in diabetes. Statins have been shown to augment the number and improve the function of endothelial progenitor cells. This study investigated the effects of statins on the viability of ischemic skin flaps in diabetic rats. METHODS: Twenty normal and 40 diabetic Sprague-Dawley rats were included in this study. Atorvastatin (10 mg/kg/day) was administered orally in 20 diabetic rats at 2 weeks before flap surgery for 21 consecutive days. Other rats received equal vehicle. Two weeks after first gavage, a 3 × 10-cm skin flap was established on the backs of rats. The necrotic area of each skin flap was measured at 7 days postoperatively. Capillary density and endothelial progenitor cells recruited to the flaps were analyzed using immunofluorescence staining. Circulating endothelial progenitor cell number was determined by flow cytometry. In vitro migration and tube formation experiments were used to analyze the function of endothelial progenitor cells. RESULTS: Atorvastatin treatment increased flap survival rate and capillary density. In addition, more endothelial progenitor cells were identified in peripheral blood and skin flaps in diabetic rats receiving atorvastatin. Atorvastatin treatment also restored the impaired function of diabetic endothelial progenitor cells in migration and tube formation. CONCLUSION: Atorvastatin notably promoted neovascularization and enhanced the viability of ischemic skin flaps in diabetic rats, which may be mediated at least partially by augmenting the number and restoring the functional capacity of endothelial progenitor cells.

Management of hypertrophic nonunion with failure of internal fixation by distraction osteogenesis.

INTRODUCTION AND AIM: Distraction osteogenesis is employed in the management of hypertrophic nonunion associated with angular deformity and shortening. This study was aimed at evaluating the outcomes of Ilizarov apparatus without bone graft or open osteotomy in cases of hypertrophic nonunion not responding to treatment with internal fixation. METHODS: We retrospectively reviewed the data of 12 patients (mean age, 46.5 years) treated for hypertrophic nonunion at our institution. All patients had two-plane angular deformities (mean, 19° and 23.5° in sagittal and frontal plane, respectively) and limb-length discrepancy (mean, 3.8cm). The Ilizarov apparatus was used to simultaneously treat the nonunion, malalignment, and limb-length discrepancy. RESULTS: The mean follow-up duration after the removal of the apparatus was 42 months. In all cases, bone union had been achieved within an average of 8 months after a single surgery, without the need for any additional procedure. Additionally, none of the patients had recurrence of limb-length discrepancy or malalignment during the follow-up period. Complications of superficial pin-tract infections and mild Achilles tendon contracture were observed, but they resolved over time. All patients were satisfied with the outcome of the surgery. CONCLUSION: Patients with hypertrophic nonunion associated with internal fixation failure can be treated by using the Ilizarov apparatus, thereby eliminating the need for bone graft or open osteotomy. Distraction osteogenesis appears to be effective as a minimally invasive percutaneous procedure in the treatment of hypertrophic nonunion with deformity and shortening.

Swan-shaped bone fixation device made of Ni-Ti shape memory alloy for treating humeral fracture in rabbits.

OBJECTIVE: To establish the animal model for treating humeral fracture with swan-shaped bone fixation device made of Ni-Ti shape memory alloy. METHODS: Models of humeral fractures was established in 30 rabbits and on one side the fracture was fixed with the Ni-Ti shape memory alloy device (SMC side) and on the other with 4-hole dynamic compression plate (DCP side). Anteroposterior radiograph of both humeri were taken at the time points of 2, 4, 8, and 12 weeks respectively after operation. RESULTS: All the rabbits survived the experiment and their forelimbs bore obviously less weight than hindlimb. In SMC side, the humeral fracture healed without either osteoporosis or external callus. The fracture healing in DCP side gave rise to obvious external callus formation, and the healing process took significantly longer time than in SMC group. CONCLUSION: The humerus of rabbit is similar to human humerus in view of their anatomic morphology and biomechanical properties, therefore rabbit humeral fracture models can be ideal for exploring the mechanism of fracture healing induced by the alloy device.

Modified deep iliac circumflex osteocutaneous flap for extremity reconstruction: anatomical study and clinical application.

BACKGROUND: The classic deep iliac circumflex osteocutaneous flap with iliac crest has been one of the most commonly used flaps for mandibular reconstruction since its advent. However, the unnecessary bulk of the 'obligatory muscle cuff' limited its widespread use. The authors describe in this article the use of a modified deep iliac circumflex osteocutaneous flap with reduced bulk and great mobility between the skin and the bone components. METHODS: This study was divided into two parts: anatomical study and clinical application. In the anatomical study, 40 sides of adult cadaveric specimens perfused with red gelatin in the arteries were dissected with the anterior superior iliac spine and the inguinal ligament serving as the anatomical landmarks to observe the course and the branches of the deep circumflex artery, with its terminal part being given priority. Clinically, five patients received modified deep iliac circumflex osteocutaneous flaps for extremity reconstruction. RESULTS: The anatomical study showed that the terminal part of the deep circumflex iliac artery ended as a musculocutaneous perforator with a diameter of 1.0 ± 0.1 mm, which could be located 6.2 ± 1.2 cm posterior and 1.5 ± 0.6 cm lateral to the anterior superior iliac spine. As for clinical application, in four cases osteocutaneous flaps survived completely, while that in one case suffered partial loss of the skin component. CONCLUSIONS: The modified deep iliac circumflex osteocutaneous flap enjoys a great degree of mobility between the skin and the bone components; it has greater manoeuvrability compared to the conventional one for the reconstruction of complex three-dimensional defects. The donor site of the skin flap is confined to the lower abdominal region, facilitating direct closure.

Mutation screening for the EXT1 and EXT2 genes in Chinese patients with multiple osteochondromas.

BACKGROUND AND AIMS: Multiple osteochondromas (MO), an autosomal dominant skeletal disease, is characterized by the presence of multiple cartilage-capped bone tumors (exostoses). Two genes with mutations that are most commonly associated with MO have been identified as EXT1 and EXT2, which are Exostosin-1 and Exostosin-2. In this study, a variety of EXT1 and EXT2 gene mutations were identified in ten Chinese families with MO. METHODS: We investigated ten unrelated Chinese families involving a total of 46 patients who exhibited typical features of MO. The coding exons of EXT1 and EXT2 were sequenced after PCR amplification in ten probands. Radiological investigation was conducted simultaneously. RESULTS: Nine mutations were identified, five in EXT1 and four in EXT2, of which three were de novo mutations and six were novel mutations. One proband carried mutations in both EXT1 and EXT2 simultaneously, and three probands, including one sporadic case and two familial cases, had no detectable mutations. CONCLUSIONS: Our findings are useful for extending the mutational spectrum in EXT1 and EXT2 and understanding the genetic basis of MO in Chinese patients.

Digital reconstruction and donor site resurfacing: a two-flap technique.

Use of a great toe pulp flap is one of the methods to repair partial soft-tissue defect of the thumb or other digits. However, the conventional application of free skin grafts to close the donor site may bring donor-site morbidity. The authors present a two-flap technique that a reverse first dorsal metatarsal artery (FDMA) flap resurfaces the defect of the free great toe pulp flap. Six patients with soft-tissue defects of the thumbs or fingers were treated with this technique. Both the pulp and reverse flaps survived uneventfully after reconstruction of the thumbs and fingers. The reverse flap to resurface the donor site on the great toe was sensate and durable. Satisfactory appearance and function were gained in all patients. Results revealed that this technique can be accepted as an alternative method when treating soft tissue defect of the thumb or finger.