Radiological evaluation of effectiveness of PCCP fixation for femoral neck fracture: med-term effectiveness in a retrospective multicenter.

Background It has been reported in the literature that the complication rate of percutaneous compression plate (PCCP) is the lowest among the new internal fixators for the treatment of femoral neck fracture (FNS). However, no multicenter studies of PCCP for FNS have been reported. This study aimed to evaluate the med-term effectiveness of PCCP in a multicenter mainly through radiology. Methods 265 patients with FNF treated with PCCP fixation in our five hospitals between January 2011 and December 2020 were retrospectively analyzed. 140 men and 125 women; aged 19-79 (mean 51.6）years. The follow-up time was 2-5 years (mean 3.1). Radiological evaluation of the therapeutic effect was the main outcome, and the function was the secondary outcome. Results One case of screw cutting out, 3 cases of screw back out, 25 cases of neck shortening, 2 cases of nonunion, 8 cases of delayed healing, and 29 cases of avascular necrosis (AVN). Bivariate correlation showed that shortening healing was correlated with age, Singh index, and Garden alignment index, poor healing was correlated with garden alignment index, and AVN was correlated with Pauwels and Garden classifications and operation timing. Further pairwise comparison analysis showed that age of > 65 and Singh index IV were dangerous factors for neck shortening, and the operation timing > 3 days, Pauwels II and III, and Garden III and IV were dangerous factors for AVN. The excellent and good rate of function in 198 patients who were readmitted for internal fixator removal or other surgery was 90.9%. Conclusion PCCP for FNS has satisfactory med-term efficacy with a low complication rate. The main complication is AVN, which is prone to occur in patients with displaced Pauwels II or III FNF and operation timing > 3 days. Another main complication is shortening healing, which is prone to occur in patients with an age of > 65 and Singh index IV.

[Study of characteristics and treatment of "kissing fracture" of humeroradial joint].

Objective: To explore the clinical characteristics and treatment of "kissing fracture" of humeroradial joint. Methods: A clinical data of 12 patients with "kissing fracture" of the humeroradial joint between January 2016 and June 2021 was retrospectively analyzed. There were 8 males and 4 females with an average age of 41.9 years (range, 15-75 years). The fractures caused by falling in 7 cases, by falling from height in 3 cases, and by sports in 2 cases. The time from injury to admission was 2-72 hours (median, 2 hours). According to Mason's classification, the radial head fractures were rated as type Ⅰ in 2 cases, type Ⅱ in 8 cases, and type Ⅲ in 2 cases. According to Grantham's classification, the humeral capitulum fractures were rated as type Ⅰ in 10 cases and type Ⅱ in 2 cases. Among them, 4 cases of Grantham type Ⅰ humeral capitulum fracture were missed by X-ray film and confirmed by CT and/or MRI. Four cases were complicated with other injuries of elbow joint. The radial head fractures were fixed with screws or mini plate in 11 cases and treated conservatively in 1 case; the humeral capitulum fractures were fixed with screw or plate in 9 cases, removed in 1 case, and treated conservatively in 2 cases. X-ray film was used to evaluate the fracture healing; Mayo Elbow Performance Score (MEPS) was used to evaluate the functional recovery of the affected limb, and the range of motion (ROM) of the elbow joint of the affected limb was detected. Results: All the incisions healed by first intention without early complications. All patients were followed up 10-24 months, with an average of 15.2 months. X-ray films showed that all fractures healed, and the healing time was 2-3 months, with an average of 2.3 months. At last follow-up, the ROM of flexion-extension of the elbow joint was 65°-161°, with an average of 136.9°; the ROM of rotation was 70°-180°, with an average of 149.2°. MEPS ranged from 70 to 100, with an average of 87.4; 8 cases were excellent, 2 cases were good, and 2 cases were fair; the excellent and good rate was 83.3%. Conclusion: The "kissing fracture" of the humeroradial joint is relatively rare, and the humeral capitulum fracture is milder than radial head fracture. X-ray examination alone can easily miss the diagnosis of Grantham type Ⅰ humeral capitulum fracture. The "kissing fracture" of the humeroradial joint is treated according to the principle of intra-articular fracture, and the good effectiveness can obtain.

A novel minimally invasive broken nail extractor for cannulated intramedullary nails: Trial and application in a few cases.

Successful and minimally invasive extraction of a broken distal end of an intramedullary nail is challenging. This study introduces a simple and reproducible technique for the extraction of broken cannulated intramedullary nails using a novel minimally invasive broken nail extractor. Five amputated adult lower-leg specimens were used to create models of the broken distal end of the cannulated intramedullary nails remaining in the medullary cavity of the distal tibia. Two orthopedic resident physicians with experience in tibial intramedullary nail implantation were selected to blindly extract the broken intramedullary nail using the novel minimally invasive broken nail extractor. The extraction outcome was assessed. The broken nail extractor was applied to 3 patients with broken intramedullary nails remaining in the medullary cavity of the distal tibia. In the lower-leg specimens, the extraction success rate was 100%, the median number of extraction times was 1.9 (range 1-3.5), and the median duration of extraction was 38 s (range 20-52 s). All the broken intramedullary nails in the 3 patients were successfully extracted without complications related to the surgery. The study shows that our technique is simple, reproducible, and has a high extraction success rate, but more case applications are needed to verify its effect.

Similarities and Differences of Induced Membrane Technique Versus Wrap Bone Graft Technique.

BACKGROUND: There are no reports on the similarities and differences between induced membrane (IM) technique and wrap bone graft(WBG) technique. OBJECTIVE: The aims of this study are to investigate the effects of IM technique and WBR technique in repairing segmental bone defects, and to analyze the similarities and differences between them. MATERIALS AND METHODS: 66 patients of tibial segmental bone defects treated by IM technique and WBG technique were retrospectively analyzed. Aged 13-69 years old with an average of 35.3 years old. IM technique was divided into early IM group (bone grafting at 6-8 weeks of bone cement filling) and late IM group (bone grafting after 8 weeks of bone cement filling). WBG was divided into titanium mesh group and line suturing cortical bone blocks group. There were 11 cases, 25 cases, 10 cases and 20 cases in the early IM group, late IM group, titanium mesh group and line suturing group, respectively. Bone healing, complications and functional recovery (Paley's method) were observed, the causes of nonunion and delayed union and factors affecting bone healing were analyzed. RESULTS: There were no significant differences in terms of age, sex, defect length, course, fixation method, defect location and preoperative function of adjacent joints among the 4 groups. All patients were followed up for 12-50 months, with an average of 20.1 months. The clinical healing time of early IM group, late IM group, titanium mesh group and line suturing group were (5.81 ± 0.75) months, (7.56 ± 1.66) months, (7.50 ± 0.70) months and (7.81 ± 1.81) months, respectively, showing significant differences among the 4 groups (P = 0.005). However, only early IM group had significant difference with other groups (P < 0.05), while no significance was found between late IM group and WBR group, between titanium mesh group and suture group (P > 0.05). There were no significant differences in healing ration, complications and functional recovery of adjacent joints among the 4 groups (P > 0.05). There were 4 cases of nonunion and delayed union, all of which were caused by poor quantity or quality of bone graft or unstable bone graft or internal fixation. CONCLUSION: Both IM technique and WBG technique are effective method for repairing segmental bone defects. In addition to mechanical encapsulation, early IM has biological osteogenesis. However, mechanical encapsulation is a common basis for repairing bone defects, and biological osteogenesis can enhance bone healing.

Application of multiple wrapped cancellous bone graft methods for treatment of segmental bone defects.

BACKGROUND: The aims of this study were to discuss the principle, therapeutic effect and influencing factors of multiple wrapped cancellous bone graft methods for treatment of segmental bone defects. METHODS: This study retrospectively analyzed the therapeutic effect of different wrapped autologous cancellous bone graft techniques on 51 patients aged (34.5 ± 11.5) years with segmental bone defects. Cancellous bones were wrapped with titanium mesh (n = 9), line mesh (n = 10), line suturing or line binding cortical block, (n = 13), or induced membrane (n = 19). The bone defeats were as follows: tibia (n = 23), radial bone (n = 10), humerus (n = 8), ulnar bone (n = 7), and femur (n = 3). The defect lengths were (5.9 ± 1.1) cm. The functionary recovery of adjacent joint was evaluated by the Paley's method and DASH, respectively. RESULTS: The incision healed by first intention in 48 cases and secondary healing in 3 cases. All patients were followed up for 19.1 ± 7.1 (12-48) months. Other than one patient with nonunion who received a secondary bone graft, all the patients were first intention of bone healing (the healing rate was 98.0%). The healing time was 6.1 ± 2.1 (3-15) months. There were no significant differences in the healing time among the 4 groups (χ2 = 1.864, P = 0.601). The incidence of complications in the grafted site was 11.8%, whereas it was 21.6% in the harvest site. At the last follow-up, all the patients had recovered and were able to engage in weight-bearing activities. The functional recovery was good to excellent in 78.4% of cases, there were no significant difference among the 4 groups (χ2 = 5.429, P = 0.143). CONCLUSIONS: Wrapped cancellous bone grafting is a modified free bone graft method that can be used in the treatment of small and large segmental bone defects as it prevents loosening and bone absorption after bone grafting. The effect of bone healing is related with the quality and quantity of grafted bone, stability of bone defects, property of wrapping material and peripheral blood supply.

[Application of meshy fascia encapsulating cancellous bone graft in repair of bone defect after limb fractures].

Objective: To investigate the effectiveness of meshy fascia encapsulating cancellous bone graft in repair of bone defect after limb fractures. Methods: A clinical data of 21 cases of traumatic bone defect after limb fractures, who were treated with meshy fascia encapsulating cancellous bone graft between June 2011 and December 2016, was retrospectively analyzed. There were 13 males and 8 females, aged 14-64 years with an average of 40.1 years. The location of bone defect included humerus in 3 cases, radius in 5 cases, ulna in 4 cases, femur in 2 cases, and tibia in 7 cases. AO classification of primary fractures were type A in 2 cases, type B in 7 cases, and type C in 12 cases. There were 14 cases of open fracture, and 7 cases of closed fracture associated with bone defect. The time from injury to bone defect repair was 5-165 days (mean, 21.3 days). The length of bone defect was 2.5-6.5 cm with an average of 4.5 cm. Results: The operation time was 86-130 minutes (mean, 101 minutes). The intraoperative blood loss was 185-647 mL (mean, 316 mL). One case of superficial infection and 2 cases of delayed healing of incision occurred after operation, and no neurovascular injury occurred. All the 21 patients were followed up 12-36 months (mean, 19 months). The clinical healing time was 2.5-7.0 months (mean, 5.4 months); no delayed healing and nonunion occurred, the bony healing rate was 100%. There was no deep infection, infection recurrence, broken of internal fixator, or refracture. At last follow-up, the grading of bony healing were all rated as excellent, and the functional recovery of the affected limb was excellent in 12 cases, good in 7 cases, and fair in 2 cases with an excellent and good rate of 90.5%. Conclusion: Meshy fascia encapsulating cancellous bone graft in repair of bone defect after limb fracture is characterized by easy to harvest fascia, simplicity of operation, no adverse reaction, lower cost, and satisfactory results.

Stereogenic cis-2-substituted-N-acetyl-3-hydroxy-indolines via ruthenium(ii)-catalyzed dynamic kinetic resolution-asymmetric transfer hydrogenation.

Ruthenium(ii)-catalyzed dynamic kinetic resolution-asymmetric transfer hydrogenation of racemic 2-substituted-N-acetyl-3-oxoindolines to cis-2-substituted-N-acetyl-3-hydroxyindolines is reported. Using the homochiral {Ru[TfDPEN](p-cymene)} catalyst with S/C = 400 in a HCO2H/Et3N mixture, up to >99.9% ee and >99 : 1 dr are obtained with high yields (79-98%). This method provides the first example of preparing enantiomerically pure indolines through asymmetric transfer hydrogenation (ATH).

Highly Enantioselective Synthesis of syn-ß-Hydroxy α-Dibenzylamino Esters via DKR Asymmetric Transfer Hydrogenation and Gram-Scale Preparation of Droxidopa.

A highly efficient preparation of enantiomerically pure syn aryl ß-hydroxy α-dibenzylamino esters is reported. The outcome was achieved via dynamic kinetic resolution and asymmetric transfer hydrogenation of aryl α-dibenzylamino ß-keto esters. The desired products were obtained in high yields (up to 98%) with excellent diastereoselectivity (>20:1 dr) and enantioselectivity (up to >99% ee). Furthermore, this method was applied for the gram-scale preparation of droxidopa.

Synthesis of a Class of Chiral-Bridged Phosphoramidite Ligands and Their Applications in the First Iridium-Catalyzed Asymmetric Addition of Arylboronic Acids to Isatins.

A series of novel chiral phosphoramidite ligands based on chiral-bridged biphenyl backbones have been prepared conveniently and characterized. The ligands complexed with [IrCodCl]2 provided the first iridium catalyst system for the asymmetric addition of arylboronic acids to N-protected isatins with high efficiency. When performed in THF/H2O at 80 °C with 2 equiv of the arylboronic acids, the transformations acquired good to excellent results (up to 98% yield and 95% ee).

Highly enantioselective synthesis of 2,3-dihydro-1H-imidazo[2,1-a]isoindol-5(9bH)-ones via catalytic asymmetric intramolecular cascade imidization-nucleophilic addition-lactamization.

Highly enantioselective catalytic asymmetric intramolecular cascade imidization-nucleophilic addition-lactamization of N(1)-alkylethane-1,2-diamine with methyl 2-formylbenzoate catalyzed by a chiral phosphoric acid represents the first efficient method for the preparation of medicinally interesting chiral 2,3-dihydro-1H-imidazo[2,1-a]isoindol-5(9bH)-ones with high yields and excellent enantioselectivities. This strategy has been shown to be quite general toward various methyl 2-formylbenzoates.