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.

Combined Medial and Lateral Approach Versus Paratricipital Approach in Open Reduction and Internal Fixation for Type C Distal Humerus Fracture: A Randomized Controlled Study.

OBJECTIVE: Olecranon osteotomy and paratricipital approaches were widely used in the treatment of type C distal humerus fracture but some disadvantages exist, so a combined medial and lateral approach was designed. The objective of this study was to investigate and compare the clinical outcomes of combined medial and lateral approach with the paratricipital approach in open reduction and internal fixation of type C distal humerus fractures. METHODS: From May 2018 to April 2020, 37 patients with type C distal humerus fracture who accepted open reduction and internal fixation in our hospital were enrolled in this study. All cases were randomly divided into two groups according to the surgical approach: combined medial and lateral approach group (19 cases), paratricipital approach group (18 cases). All of the patients received open reduction and double vertical plates fixation. The operation and follow-up indexes, including operation time, blood loss, incision length, triceps muscle strength, flexion-extension arc of elbow and forearm rotation arc, were recorded and compared. Caja score was used to assess the quality of fractures reduction. Mayo Elbow Performance Score (MEPS) was used to evaluate the elbow function in the follow-up. Complications such as incision infection, ulnar nerve injury, degenerative osteoarthritis, and heterotopic ossification were analyzed. RESULTS: The differences in age, gender, and AO classification of fractures between two groups were not statistically significant (p > 0.05). The sum of medial and lateral incision length of combined approach group was longer than the midline incision of paratricipital approach group (15.4 ± 0.8 vs. 14.6 ± 0.8, p < 0.05), but there was no significant difference in operation time (103.5 ± 10.2 vs. 106.0 ± 8.8, p > 0.05), blood loss (71.3 ± 24.5 vs. 72.8 ± 24.6, p > 0.05), and Caja score (16.05 ± 5.67 vs. 15.56 ± 5.66, p > 0.05). During the follow-up, the MEPS of combined approach group was higher than that of paratricipital approach group at 3 months postoperatively (80.5 ± 5.7 vs. 68.9 ± 8.1, p < 0.05), but there was no significant difference in MEPS at 6 months postoperatively (83.9 ± 6.6 vs. 79.7 ± 7.0, p > 0.05) and at the last follow-up (86.8 ± 7.1 vs. 86.9 ± 7.7, p > 0.05) between the two groups. There was no significant difference in triceps muscle strength (p > 0.05), flexion-extension arc (126.8 ± 5.3 vs. 128.9 ± 6.0, p > 0.05), and forearm rotation arc (163.2 ± 5.3 vs. 163.6 ± 4.8, p > 0.05) at the last follow-up. Although the incidence of complication of combined approach group (15.8%) was lower than that of paratricipital approach group (22.2%), the difference was not statistically significant (p > 0.05). CONCLUSIONS: The combined medial and lateral approach was an effective and safe way of open reduction and internal fixation for type C distal humerus fractures. Compared with the paratricipital approach, the combined medial and lateral approach could restore the elbow function more quickly postoperatively, and the long-term results were comparable.

[Managements of open wounds from an earthquake].

OBJECTIVE: To explore the surgical managements of open wounds from 5·12 Wenchuan Earthquake. METHODS: In this report, fifty one patients with open wounds were treated after transported into West China Hospital from May 12 to 26 in 2008 after 5·12 Wenchuan Earthquake. Among 51 cases, open wounds were due to open fractures (n = 8), fasciotomy (n = 6), exposed bone (n = 8) and defects of skin and soft tissue (n = 29). All cases had wound infections. Sixty operations were performed, including muscle and myocutaneous flap (n = 4), skin grafting (n = 30), NPWT (negative pressure wound therapy) (n = 2) and debridement (n = 24). RESULTS: Four cases of muscle and myocutaneous flaps survived with an excellent blood circulation. And 30 cases of skin grafting had a survival rate of over 90%, 2 cases of NPWT and 24 cases of debridement required further treatment. CONCLUSION: With adequate surgical managements, open wound healing from an earthquake may be accelerated and the functions maximally preserved.

[Surgical treatment of sinus tract in diabetic foot with adjacent pedicle fascia flap and arthrodesis].

OBJECTIVE: To study the therapeutic effect of adjacent pedicle fascia flap filling and arthrodesis in the regional management of sinus tract in diabetic foot. METHODS: From February 2007 to August 2010, 6 patients suffering diabetic foot with sinus tract were included. There were 4 male and 2 female patients, aged 47 to 68 (averaging 58.3 +/- 6.7). One case had the entrance of sinus tract in the heel, and its base located deep in the calcaneus. Three cases had the sinus tract in the vola or dorsum of the foot, in which 1 with a perforating tract connecting the vola and the dorsum. Another 2 cases were in the toes, both located around joints. Under the effective treatments of anti-infection, anti-coagulation and control of blood sugar, blood pressure as well as blood lipid level, the patients were subjected to surgical treatments of sinus tract, the sinuses in the heel, sole and dorsum of the feet were filled up with facial flap, and those in the toes were eliminated using arthrodesis. RESULTS: All the 6 patients received rational debridement. Four patients were treated with adjacent fascia flap filling, the other two were treated with arthrodesis. The sinus tracts healed 14-20 d after surgery in all patients. One patient developed skin necrosis at the edge of the incision in the dorsum of the foot and another whose sinus located in the toe suffered inflammation and exudation. Both patients recovered after dressing replacement, antiseptic therapy and blood sugar regulation for a period of time. CONCLUSION: Appropriately designed pedicle fascia flap can provide satisfactory healing for sinus in the heel, vola and dorsum, and arthrodesis is a safe and effective way for that in the toes. Rational debridement is the key prerequisite for healing of sinus tract in diabetic foot.

Surgical Treatment of Internal Fixation Failure of Femoral Peritrochanteric Fracture.

OBJECTIVE: To investigate the factors, surgical treatment methods and clinical effect of internal fixation failure of intertrochanteric and subtrochanteric fractures. METHODS: From June 2015 to May 2019, arthroplasty and internal fixation revision were used to treat 18 cases of internal fixation failure of intertrochanteric and subtrochanteric fractures. There were 10 males and eight females, with an average age of 67.3 years (38-92 years). The 16 cases of initial intertrochanteric fractures were classified according to AO/OTA:13 cases of A2 and 3 cases of A3, the other 2 cases were subtrochanteric fractures (Seinsheimer type IV). The internal fixation failure was treated with total hip arthroplasty (6 cases), bipolar hemiarthroplasty (4 cases), revision with proximal femoral lockingplate (4 cases) and extend intramedullary nail (4 cases). RESULTS: All patients were followed up for an average of 24.7 months (range, 12 to 36 months). The average operative time was 111.4 min (range, 72 to 146 min) and the average intraoperative blood loss was 403.6 mL (range, 200 to 650 mL). The average time of fracture union was 6.9 months (range, 5 to 9 months) for cases of internal fixation revision. The operative time of the arthroplasty group was shorter than the revision group (P < 0.001), and the intraoperative blood loss of the arthroplasty group was less than the revision group (P = 0.001). The affected limb shortening of postoperative (0.21 ± 0.19 cm) was better than preoperative (2.01 ± 0.60 cm) (P < 0.001), while the limb shortening of the arthroplasty group (0.11 ± 0.21 cm) was less than the revision group (0.33 ± 0.09 cm) (P = 0.015). At the last follow-up, all injured limbs regained walking function, and the Harris hip score was 81.3 ± 9.4 points. The Harris score of postoperative was better than preoperative (33.4 ± 5.9 points) (P < 0.001), while there were no significant differences between the arthroplasty group and the revision group at 3 months (76.5 ± 8.5 vs 71.1 ± 10.6, P = 0.249), 6 months (80.9 ± 7.9 vs 78.9 ± 12.9,P = 0.687) postoperative and the last follow-up (80.5 ± 8.3 vs 82.3 ± 11.7, P = 0.716) respectively. CONCLUSION: For internal fixation failure of peritrochanteric fractures, young patients could accept internal fixation revision to restore normal anatomical structure, correct varus deformity and autograft; while elderly patients and patients with damaged femoral head could be treated with arthroplasty to restore walking function.

[Analysis of patients with bone injury in Wenchuan earthquake].

OBJECTIVE: To evaluate the patients with bone injury in Wenchuan earthquake. METHODS: From May 12th to June 15th 2008 the data of 1410 patients with bone injury in Wenchuan earthquake were analyzed to evaluate clinical intervention and remedy-managing experience. RESULTS: The 1410 patients average age was from 4 to 103 years old. And 744 cases (52.7%) suffered from blunt injuries, 379 cases (26.9%) from buried injuries, 287 cases (20.4%) from falling injuries; And 1317 cases were with fracture, 93 with limbs soft tissue injuries; 261 patients combined with other parts of injuries including 45 cases with paralysis; 66 cases were with crush syndrome, 25 with gas gangrene, 76 with acute kidney failure, 26 with multiple organ failure. And 912 operations were performed including 402 fracture fixation, 224 debridement, 152 debridement and suture, 85 amputation, 29 implant skin, 8 fixation of joint dislocation, 5 surgical flaps transplantation, 4 nerve and tendon suture, 2 arthroscopes, 1 joint replacement. Among the 66 crush syndrome patients, 49 accepted continuous renal replacement therapy, in which 9 cases were bleeding from named arteries and 20 blood vessels were getting embolism. Among the 1410 cases, 1 died from multiple organ failure. CONCLUSIONS: Among the patients with bone injury in Wenchuan earthquake, the elderly patients are more than the youth; The injuries are always combined with other complications; Opened injuries are polluted severely; It is difficult to deal with the crush syndrome; Paraplegia cases are less, but the amputees are more.

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.

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.

[Percutaneous screw fixation for pelvic fractures with fluoroscopy-based navigation].

OBJECTIVE: To investigate the applications of fluoroscopy-based navigation in pelvic fractures and related surgical considerations. METHODS: From May 2010 to December, 16 patients with pelvic fractures were treated with computerized navigation. There were 12 males and 4 females with an average age of 37 years (ranged from 20 to 54 years). Fractures were caused by traffic accident in 5 cases, crush injury in 5 cases and falling from height in 6 cases. Based on the Tile classification, there were 15 cases of Tile C type and 1 case of Tile B type. In these patients, 4 patients were treated with sacroiliac screw fixation; 2 patients were treated with sacroiliac screw fixation, screw fixation for pubic symphysis diastasis and pubic fractures; 8 patients were treated with sacroiliac screw fixation and screw fixation for pubic fractures; 2 patients were treated with screw fixation for pubic fractures. The index such as screw inserting time, accurance of inserting screws, intra-operative blood losing, injuries of nerve, vascular and other organs, reduction conditions were observed. RESULTS: A total of 36 screws were inserted. The average time was 20 min for each screw placement. The blood loss ranged from 10 to 20 ml. There were no wound infections, neurovascualr injuries and other organ injuries. The postoperative pelvic X-ray and three-dimensional CT showed that the fractures had good reduction and all the screws had good position. CONCLUSION: Percutaneous screw fixation of pelvic fractures with fluoroscopy-based navigation have advantages such as little trauma, less blood loss, little complication, reliable fixation and no blood transfusion, which can reconstruct the stability of the pelvic ring, but need adequate preoperative reperation and high requirements for the surgeon.

[A medium-term analysis on of therapeutic effects of locking proximal humerus plate for the treatment of comminuted fractures of proximal humerus].

OBJECTIVE: To investigate the medium-term curative effects of locking proximal humerus plate for the treatment of comminuted fractures of proximal humerus, and provide evidences for the clinical practice. METHODS: From August 2005 and April 2008, 23 patients with comminuted fractures of proximal humerus were treated with locking plates, including 12 males and 11 females, aged 27 to 76 years old (averaged 51.5 years old). There were 18 cases of traffic accident injuries, 4 cases of falls injuries, and 1 case injured after heavy pressure. According to Neer classification, 11 cases were three-part fractures, and 12 cases were four-part fractures. Outcomes were assessed with radiography and the Constant-Murley (C-M) shoulder evaluation. RESULTS: All the patients got primary healing of incisions. Twenty-three patients were followed up, and the duration ranged from 17 to 49 months, with an average of 35.25 months. Twenty patients had fracture healing during 4 to 7 months after operation. There was no significant differences among 3, 6 and 12 months after operation in C-M scoring. The average C-M score was (79.85 +/- 17.23) points (38 to 100 points) at the 12th month after operation, 8 cases got an excellent result, 8 good, 5 fair, and 2 poor. In the LPHP plus bone graft group 6 cases got an excellent result, 4 good, 3 fair, and 1 poor; in LPHP fixation group 2 excellent, 4 good, 2 fair,and 1 poor. CONCLUSION: The medium-term curative effect of the locking proximal humerus plate in the treatment of proximal humeral fractures is significant. For the comminuted fractures of proximal humerus combined with osteoporosis and bone defects, bone graft should be performed routinely.