Biomechanical difference of different fixation methods in bone healing of distal tibial comminuted fractures analyzed by finite element method / 中国组织工程研究

BACKGROUND:The treatment of distal tibial comminuted fractures with soft tissue injury has always been challenging.The new retrograde tibial nailing and supercutaneous locking plate are important treatment methods,but their strain and stress shielding at the fracture end during different periods of fracture healing and different load conditions have not been reported. OBJECTIVE:To explore the biomechanical stability of retrograde tibial nailing and supercutaneous locking plate in different periods of fracture healing by finite element analysis to offer a scientific foundation for clinical application and rehabilitation exercise. METHODS:The finite element model of distal tibial comminuted fracture was established by utilizing the CT data of the tibia from a 40-year-old healthy male.Retrograde tibial nailing,supercutaneous locking plate,and callus models were assembled in accordance with the principle of fracture fixation.The finite element analysis was performed using ANSYS software to compare the displacement of the fracture end,the stress shielding of the tibia,the stress of the callus,and the stress distribution of the tibia and the fixation device during different periods of fracture healing. RESULTS AND CONCLUSION:(1)The relative displacement of the tibial fracture decreased gradually with the healing of the fracture,and the displacement decreased significantly after 3 months.At 0 and 1 months after operation,the vertical displacement and total displacement of the supercutaneous locking plate group were higher than those in the retrograde intramedullary nail group.The Z-axis displacement(horizontal medial and lateral displacement)of the two fixation methods was more obvious than the X-axis and Y-axis,and the Z-axis displacement of supercutaneous locking plate group was the most obvious.The maximum Z-axis displacement of the two fixation methods was located on the outside of the tibia,and the minimum displacement was located on the inside of the tibia.(2)The stress shielding rate at different periods of fracture healing gradually decreased with time.The stress shielding rate of the retrograde intramedullary nail was higher than that of the supercutaneous locking plate at different stages of fracture healing.After 3 months,the stress shielding rate of the supercutaneous locking plate was reduced to about 4%,and the stress shielding rate of the retrograde intramedullary nail was reduced to about 40%.(3)The stress of the stress concentration site of the callus in the two fixation methods increased with the increase of the load,and the stress of the callus in the supercutaneous locking plate group was always greater than that in the retrograde intramedullary nail group.The maximum stress distribution of the callus was approximately equally distributed among the two modes of fixation,both in the lateral portion of the tibia.(4)As the fracture healed,the maximum stress of the tibia in the two groups decreased gradually,and the stress in the supercutaneous locking plate group was always greater than that in the retrograde intramedullary nail group.The average stress of the maximum stress area of the tibia in the supercutaneous locking plate group under 1 500 N load was 285 MPa,while that in the retrograde intramedullary nail group was 26 MPa.(5)As the fracture healed,the stress of the fixation device in the two groups decreased gradually,and the stress in the supercutaneous locking plate group was significantly higher than that in the retrograde intramedullary nail group.After 3 months,the stress of the two fixation devices decreased significantly.(6)It is indicated that in the early stage of fracture healing,the strain on the fracture end in the retrograde intramedullary nail group is small,and the maximum stress of the tibia is moderate,allowing early loaded.The fractured ends in the supercutaneous locking plate group had too large strain and too large maximum stress of the tibia,which needed to be partially loaded under protection and could not be fully loaded.In the middle and late stages of fracture healing,the tibial retrograde intramedullary nail and the supercutaneous locking plate could be completely loaded,and the stress shielding rate of the supercutaneous locking plate was significantly lower than the tibial retrograde intramedullary nail.

Distribution characteristics of humeral head screws in treatment of proximal humeral fractures with proximal humerus internal locking system plate / 中国组织工程研究

BACKGROUND:Proximal humerus internal locking system locking plate is the most commonly used fixation method for proximal humeral fractures,but its failure rate is still high in clinical practice.Reasonable screw placement is an important factor affecting the stability of internal fixation. OBJECTIVE:To investigate the distribution of humeral head screws in the treatment of proximal humeral fractures with proximal humerus internal locking system plate and its influence on internal fixation failure. METHODS:From January 2017 to December 2021,data from patients with proximal humeral fractures undergoing proximal humerus internal locking system plate in Third Affiliated Hospital of Guangzhou University of Chinese Medicine were retrospectively analyzed.A total of 124 patients were enrolled,including 16 males and 108 females,at the age of≥60 years.According to whether there was internal fixation failure after operation,they were divided into normal group(n=101)and internal fixation failure group(n=23).The patient's age,gender,fracture type,the integrity of the medial column,plate height,neck-shaft angle,whether the talus screw was inserted,and the number of humeral head screws,were collected.The humeral head was divided into eight zones according to the postoperative digital radiography anteroposterior film,and the distribution characteristics of the screws in each zone were collected,and the heat map of the screw distribution was drawn. RESULTS AND CONCLUSION:(1)There were no significant differences between the two groups in age,gender,fracture type,the integrity of the medial column,plate height,neck-shaft angle,whether to insert talus screws,and the number of humeral head screws(P>0.05).(2)The heat map showed that the humeral head screws were evenly distributed in the normal group,mainly scattered in zones 4,6,and 7.However,the screw distribution in the internal fixation failure group was not uniform,mainly concentrated in zones 4 and 6.In addition,in the ideal area of talus screws(7/8 zone),there were significantly more screws in the normal group than in the internal fixation failure group.(3)It is indicated that in the treatment of proximal humeral fractures with proximal humerus internal locking system plate,the uniform distribution of humeral head screws is the key to ensuring the internal fixation effect.A reasonable distribution of humeral head screws helps to improve the treatment effect and the success rate of internal fixation.

Effect of locking plate combined with cortical screw internal fixation on ankle function and quality of life in patients with ankle fracture combined with inferior tibiofibular separation / 临床外科杂志

Objective To investigate the effect of locking plate combined with cortical screw internal fixation on ankle function and quality of life in patients with ankle fracture with tibiofibular separation.Methods A total of 120 patients with ankle fracture and distal tibiofibular separation treated in our hospital from May 2020 to December 2021 were selected and divided into control group and observation group according to random number table method,with 60 patients/group.The control group was treated with cortical screw fixation alone,and the observation group was treated with locking plate combined with cortical screw internal fixation.Before surgery and 6 months after surgery,the recovery function of the two groups was compared.X-ray,operation duration,healing time,intraoperative blood loss,postoperative complications were compared,and the living ability of the two groups of patients was evaluated.Results Before treatment,there was no difference in joint function between the two groups(P＞0.05).After treatment,the longest walking of the control group(15.89±0.85),foot alignment(15.06±0.71),pain response(29.03±4.48)and ground walking(15.65±0.59).The longest walking distance(16.19±0.87),foot alignment(15.29±0.76),pain response(31.24±4.55)and ground walking(15.96±0.68)in the observation group,which were higher than those in control group(P＜0.05).Compared with the control group,the intraoperative blood loss and healing time in the observation group were lower(P＜0.05).BI index of the two groups before treatment had no difference(P＞0.05);After treatment,BI index of observation group was higher than that of control group(P＜0.05).There was no difference in the total complication rate between the two groups(P＞0.05).Conclusion Locking plate combined with cortical screw internal fixation has a good therapeutic effect on improving ankle function,reducing intraoperative blood loss,promoting healing and improving behavioral ability in the treatment of ankle fracture combined with hypotibiofibular syndesmosis injury.

Finite element analysis of three different minimally invasive fixation methods for distal tibial fractures with soft tissue injury / 中国组织工程研究

BACKGROUND:The treatment of distal tibial fractures with soft tissue injury has always been challenging,and the new retrograde tibial nailing is a new choice.Up to now,there were few reports on the biomechanical properties between the new retrograde tibial nailing,anterograde intramedullary nailing and supercutaneous locking plate. OBJECTIVE:To explore the biomechanical stability of new retrograde tibial nailing,antegrade intramedullary nailing and supercutaneous locking plate in the treatment of distal tibial fractures with soft tissue injury using finite element analysis so as to offer a scientific foundation for clinical application. METHODS:The finite element model of transverse distal tibia fracture was established by relevant software utilizing the CT data of the tibia from a 42-year-old healthy male.Retrograde tibial nailing,antegrade intramedullary nailing and supercutaneous locking plate finite element models were assembled under the principle of fracture fixation.Finally,meshing,applying loads,and data processing were accomplished with the ANSYS 2019 software.Moreover,the stress distribution and displacement of the tibia and internal fixation of each model were compared. RESULTS AND CONCLUSION:(1)The displacement of fracture end in the three groups increased with the increase of load.In all mode loads,the average displacement of the fracture end was the least in the retrograde tibial nailing group,followed by the supercutaneous locking plate group,and the highest in the antegrade intramedullary nailing group.At 800 N vertical load,the displacement difference of the fracture end was statistically significant(P<0.05).There was no statistical significance in other load modes.(2)Under different loads,the tibial stress in the three groups was the highest in the middle of the tibia,and gradually decreased to the proximal and distal ends.The stress distribution of the tibial shaft was the highest in the retrograde tibial nailing group,followed by the supercutaneous locking plate group,and the least in the antegrade intramedullary nailing group.(3)Under different loads,the stress of the tibial stress raiser in the three groups was significantly higher in the supercutaneous locking plate group than in the other two groups,with statistical significance(P<0.05).(4)Under different loads,the stress of the fixators in the three groups was the largest in the supercutaneous locking plate group,followed by the retrograde tibial nailing group,and the minimum in the antegrade intramedullary nailing group.There were significant differences in the stress of fixator stress raiser among the three groups under different loading modes(P<0.05).(5)It is indicated that all three fixation methods have the good anti-rotation ability and axial stability.Retrograde tibial nail shows better biomechanical stability.

Finite element analysis of intramedullary nail and locking plate fixation for proximal humeral fractures / 中国组织工程研究

BACKGROUND:Intramedullary nails and locking plates are widely used in the treatment of proximal humeral fractures,but there is no consensus on the choice of internal fixation. OBJECTIVE:To compare the biomechanical stability of intramedullary nails and locking plates in the treatment of two-part and three-part proximal humeral fractures by finite element analysis. METHODS:CT data of the humerus of a volunteer were collected and imported into Minics 21.0,Geomagic Wrap,Soildwork 2017,and Abaqus 2021 to establish finite element models of two-part and three-part fractures treated with two internal fixation methods,respectively.Group A:two-part fracture fixed with intramedullary nail model;group B:two-part fracture fixed with locking plate model;group C:three-part fracture fixed with intramedullary nail model;group D:three-part fracture fixed with locking plate model.The stress distribution,displacement degree,and maximum value of the humerus and internal fixation were compared and analyzed. RESULTS AND CONCLUSION:(1)The maximum stress and maximum displacement of the humerus were the smallest in the model of group A,and the maximum stress and maximum displacement of the humerus were the largest in the model of group D.The stress of the locking plate group was mainly concentrated in the medial inferior part of the humeral head and the screw hole area,while the stress of the intramedullary nail group was mainly concentrated around the fracture line and the lateral inferior part of the surgical neck of the humerus.There is no significant difference in displacement distribution between the two.It is mainly concentrated in the distal humerus.(2)The maximum stress value of the intramedullary nail was the lowest in the model of group A,and the maximum stress value of the locking plate was the highest in the model of group D.The maximum stress of the two internal fixations was mainly concentrated in the talar screw and the connection with the internal fixation.The stress cloud distribution of the locking steel plate was concentrated,while the stress cloud distribution of the intramedullary nail was more uniform.(3)The results showed that compared with the locking plate,the intramedullary nail had more biomechanical advantages,and this advantage was more obvious in three-part fractures.

Finite element analysis of the stability of Mason type Ⅲ radial head fracture fixed with three cross-bridge headless compression screw and locking plate / 中国骨伤

OBJECTIVE@#To compare the biomechanical stability of three cross-bridge headless compression screws and locking plates in the fixation of Mason type Ⅲ radial head fractures by finite element method.@*METHODS@#Using reverse modeling technology, the radial CT data and internal fixation data of a healthy 25-year-old male were imported into the relevant software. Three-dimensional finite element model of 3 cross-bridge headless compression screws and locking plates for MasonⅢ radial head fractures were established, and the radial head was loaded with 100 N axial loading. The maximum displacement, maximum Von Mises stress and stress distribution of the two groups were compared.@*RESULTS@#The maximum displacements of the three cross-bridge screws group and locking plate group were 0.069 mm and 0.087 mm respectively, and the Von Mises stress peaks were 18.59 MPa and 31.85 MPa respectively. The stress distribution of the three screws group was more uniform.@*CONCLUSION@#Both internal fixation methods can provide good fixation effect. CoMPared with the locking plate fixation method, the 3 cross-bridge headless compression screws fixation is more stable and the stress distribution is more uniform.

Treatment of the aged patients with unstable proximal humeral fracture with a locking plate and an intramedullary titanium mesh / 中华创伤骨科杂志

Objective:To evaluate the radiological and clinical outcomes of the aged patients with unstable proximal humeral fracture (UPHF) treated with a locking plate and an intramedullary titanium mesh.Methods:A retrospective study was conducted to analyze the 43 aged patients with UPHF who had been admitted to Department of Orthopedics, Zhongda Hospital Affiliated to Southeast University from January 2017 to July 2019. There were 13 males and 30 females with an age of (71.3±10.3) years (from 60 to 83 years). All patients were treated with a locking plate and an intramedullary titanium mesh to support. The postoperative imaging measurements included changes in humeral head height (HHH) and neck-shaft angle (NSA) (the difference between 3 years after surgery and the second day after surgery, taken as an absolute value); the postoperative clinical measurements included visual analogue scale (VAS), range of shoulder motion, Constant-Murley shoulder functional score (Constant score), American Shoulder and Elbow Surgeons (ASES) score, and incidence of complications.Results:All patients were followed up for (39.2±2.3) months after surgery. The change in HHH at 3 years after surgery was (1.5±1.1) mm, and the change in NSA at 3 years after surgery 3.3°±2.6°. At 3 years after surgery, the VAS score was (2.2±1.3) points, the Constant score (79.2±9.1) points, and the ASES score (78.9±9.2) points; the range of forward extension was 143.2°±20.8°, the range of outward extension 139.3°±23.1°, and the range of outward rotation 55.1°±4.7°. Complications after surgery were found in 6 patients, including humeral head necrosis in 2 cases, ectopic ossification in 1 case, and infection in 3 cases.Conclusion:In the treatment of the aged patients with UPHF, a locking plate combined with an intramedullary titanium mesh can help to restore the medial column support, leading to fine radiological and clinical outcomes.

Minimally invasive fixation with a locking plate for Sanders Ⅱ and Ⅲ calcaneal fractures via the tarsal sinus approach / 中华创伤骨科杂志

Objective:To evaluate the minimally invasive fixation with a locking plate via the tarsal sinus approach in the surgical treatment of Sanders Ⅱ and Ⅲ calcaneal fractures.Methods:A retrospective study was conducted to analyze the 65 patients who had been surgically treated for Sanders Ⅱ and Ⅲ calcaneal fractures at Department of Foot and Ankle Surgery, Binzhou Medical College Hospital from April, 2019 to September, 2020. There are 44 males and 21 females with an age of (42.5±10.4) years, and 46 Sanders type Ⅱ fractures and 19 Sanders type Ⅲ ones. The patients were divided into group L and group S according to surgical methods. Group S of 35 cases was fixated with a minimally invasive locking plate through the tarsal sinus incision while group L of 30 cases fixated with a locking plate through the L-shaped incision. The 2 groups were compared in terms of waiting time before surgery, surgical time, hospital stay, intraoperative bleeding, visual analogue scale (VAS) at 3 days after surgery, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score at 1 year after surgery, excellent and good rate by the Maryland foot function score, B?hler angle, Gissane angle, varus angle, and complications.Results:There was no significant difference in the general data before surgery between the 2 groups, showing comparability ( P>0.05). All patients were followed up for (13.3±1.6) months after surgery. The waiting time before surgery [(2.8±1.8) d], surgical time [(80.7±9.9) min], hospital stay [(6.7±1.9) d], intraoperative bleeding [(54.3±14.2) mL], and VAS at 3 days after surgery [6 (5, 7) points] in group S were all significantly less or lower than those in group L [(8.2±2.8) d, (105.0±15.7) min, (14.6±3.4) d, (74.3±12.8) mL, and 7 (6, 8) points] (all P<0.05). At one year after surgery, the AOFAS ankle-hindfoot score [(90.1±3.5) points] in group S was significantly higher than that in group L [(83.5±6.7) points] ( P<0.05), but there was no statistically significant difference in the excellent and good rate by the Maryland foot function score between the 2 groups [91.4% (32/35) versus 86.7% (26/30)] ( P=0.695). The B?hler angle, Gissane angle, and varus angle were significantly improved in all patients one year after surgery compared with the values before surgery ( P<0.05), but there were no statistically significant differences within either group or between the 2 groups at 3 days or 1 year after surgery ( P>0.05). Peroneal muscle pain was reported in 1 case in group S; there were 2 cases of skin necrosis, 1 case of incision hematoma and 1 case of sural nerve injury in group L. Conclusion:The minimally invasive fixation with a locking plate via the tarsal sinus approach is an effective treatment for Sanders Ⅱ and Ⅲ calcaneal fractures.

Clinical study of double plate system in the treatment of complex proximal humeral fractures in the elderly / 中国骨伤

OBJECTIVE@#To explore the clinical outcomes of anteromedial combined with lateral locking plate for complex proximal humeral fractures in the eldery.@*METHODS@#From June 2018 to October 2020, 30 patients who underwent surgical treatment for Neer grade 3 to 4 proximal humeral fractures, including 8 males and 22 females, aged from 51 to 78 years old with an average of (61.5±7.5) years old. Of them, 15 patients had fractures fixed with anteromedial combined with lateral locking plate(ALLP group), whereas 15 received internal fixation with proximal humerus locking plate only(PHLP group). The clinical data, simple shoulder test (SST), humeral head height loss, varus angle and shoulder range of motion were compared between the two groups.@*RESULTS@#All fractures were healed. The follow-up time ranged from 12 to 24 months, with an average of(14.3±2.9) months. The operation time of ALLP group was longer than that of PHLP group (P<0.05). There was no significant difference in intraoperative blood loss between the two groups (P>0.05). There was no significant difference in SST score between the two groups at 1, 3 and 12 months after operation (P>0.05). In terms of radiographic measurement, there was no significant difference in humeral head height loss and varus angle between the two groups at 1 and 3 months after operation (P>0.05). At 12 months after operation, the height loss and varus angle of humeral head in ALLP group were lower than those in PHLP group (P<0.05). In shoulder range of motion, the range of forward elevation in ALLP group was larger than that in PHLP group 1 year after operation(P<0.05). There was no significant difference in external rotation between the two groups.@*CONCLUSION@#Anteromedial combined with lateral locking plate in the treatment of complex proximal humeral fractures in the elderly can increase the stability of the medial column and obtain a good fracture prognosis. But there are also disadvantages such as longer operation time, so it should be individualized according to the fracture type of the patient.

Treatment of four-part proximal humerus fractures with depressed humeral head collapse using strut allograft with locking plates / 中国骨伤

OBJECTIVE@#To evaluate the clinical outcomes of allogeneic femoral head as strut allograft combined with proximal humeral internal locking system (PHILOS) in the treatment of proximal humeral Neer grade Ⅳ fracture with humeral head collapse.@*METHODS@#From January 2018 to November 2020, 18 patients with Neer grade Ⅳ fracture with humeral head collapse were treated with strut allograft with PHILOS, including 4 males and 14 females, aged from 55 to 78 years old, with an average of (68.11±7.20) years old. The operation time, intraoperative bleeding, postoperative drainage volume, fracture healing time, neck-shaft angle and the height of the humeral head, failure of internal fixation the shoulder function at the last follow-up was assessed using Neer's scoring system.@*RESULTS@#All 18 patients were followed up, and the duration ranged from 10 to 12 months, with an average of (11.08±0.65) months. The operation time was (66.44±5.06) min, the intraoperative bleeding volume was (206.67±36.14) ml, the postoperative drainage volume was (76.11±9.63) ml, and the fracture healing time was (17.28±3.92) weeks. At the last follow-up, the degree of loss of neck-shaft angle was (5.44±0.86) ° and the loss of the height of humeral head was (1.43±0.27) mm. All 18 patients had healing without complications such as fracture, withdrawal, penetration of internal fixation and necrosis of humeral head. According to Neer's evaluation standard, the total score was (89.61±5.60), 10 cases got an excellent result, 6 good, 2 fair.@*CONCLUSION@#Allogeneic femoral head combined with PHILOS is an appropriate treatment for the four-part proximal humerus fractures with humeral head collapse, exhibiting good clinic outcome.

Clinical application of special fluoroscopy method in the treatment of distal radius fractures with volar locking plate / 中国骨伤

OBJECTIVE@#The relationship between the distal screws and the wrist articular surface was assessed by the additional lateral oblique fluoroscopic view during the operation, and the dorsal tangential view of the wrist was used to observe whether the distal screw penetrated the dorsal cortex, so as to evaluate the clinical efficacy of the volar locking plate in the treatment of distal radius fractures.@*METHODS@#From January 2020 to June 2021, 45 cases of fresh distal radius fractures were treated using the volar Henry's approach, including 20 males and 25 females, aged from 32 to 75 years old with an average of (52.4±8.1) years old. During the operation, they were divided into 2 groups according to the different intraoperative fluoroscopic views:the control group of 20 cases, treated with standard anteroposterior and lateral fluoroscopic view;25 cases in the observation group, additional lateral oblique fluoroscopic view and dorsal tangential view of the wrist were taken. The wrist joint function score and postoperative complications were evaluated at 6 weeks, 3 and 6 months after operation between two groups.@*RESULTS@#All 45 patients were followed up and the duration ranged from 6 to 14 months, with an average of (10.8±1.7) months, all patients achieved bone union and the incision healed well. The incidence of postoperative complications in the observation group was lower than that in the control group, and the difference was statistically significant (P<0.05). In terms of Gartland-Werley score of wrist joint function, the score of wrist function in the observation group was (4.58±1.31) at 6 weeks, (2.98±0.63) at 3 months and (1.95±0.65) at 6 months post-operatively, which were better than those in the control group (6.32±1.96) at 6 weeks, (3.63±0.76) at 3 months and (2.43±0.73) at 6 months. The difference was statistically significant (P<0.05). In the observation group, 7/25 cases(28%) were found to have screw penetration during the operation by additional lateral oblique and dorsal tangential radiograph fluoroscopic views of wrist.@*CONCLUSION@#The addition of lateral oblique and dorsal tangential during the operation could improve the accuracy of distal screw placement, reduce postoperative complications, and achieve early functional exercise.

Analysis of the causes of soft tissue complications after volar locking plate for the treatment of dorsal displaced distal radius fractures / 中国骨伤

OBJECTIVE@#To investigate the causes of soft tissue complications in patients with dorsal displacement distal radius fractures (DRF) after volar locking plate surgery.@*METHODS@#From July 2016 to May 2021, 112 patients with dorsal displacement DRF were treated with volar locking plate surgery, including 45 males and 67 females. The average age was (46.24±10.08) years old, ranging from 18 to 85 years old. According to whether there were soft tissue complications after operation, they were divided into complication group (40 cases) and non complication group (72 cases). Compared with preoperation, the radial metacarpal inclination and ulnar deflection angle, wrist flexion activity and dorsal extension activity, and grip strength of patients after operation were significantly improved (P<0.05). Compared with the non complication group, the proportion of patients in the complication group whose age was>60 years, body mass index (BMI) more than 30 kg·m-2, smoking, diabetes, fracture type C, open fracture and operation time more than 90 min was higher (P<0.05). The age, BMI, smoking, diabetes, fracture AO classification, fracture type and operation time were analyzed by multifactor Logistic regression to determine the independent risk factors affecting the occurrence of postoperative soft tissue complications of patients, establish a nomogram prediction model, and evaluate the model.@*RESULTS@#At the latest follow-up, the excellent and good rate of wrist joint function recovery was 83.93% (94/112), and the excellent and good rate of fracture reduction was 84.82% (95/112). Multivariate Logistic regression analysis showed that age more than 60 years old, diabetes, fracture type C, open fracture and operation time more than 90 min were independent risk factors for postoperative soft tissue complications (P<0.05). The receiver operating characteristic (ROC), calibration curve and clinical decision curve of the nomogram prediction model showed discrimination, accuracy and validity were good.@*CONCLUSION@#Age more than 60 years, diabetes mellitus, fracture type C, open fracture, and operation time more than 90 min are all independent risk factors for soft tissue complications after DRF volar plate fixation. In clinical treatment, perioperative soft tissue management should be done in such patients to prevent complications.

Augmenting locking plate with autologous bone graft for the treatment of nonunion of long bone fracture in the lower extremity with retaining of the original intramedullary nail / 中国骨伤

OBJECTIVE@#To explore clinical effect of attaching locking plate with bone grafting based on retaining the original intramedullary nail in treating non-union after intramedullary nail fixation of long shaft fractures of lower limbs.@*METHODS@#A retrospective study was conducted on 20 patients treated with non-union fractures after intramedullary nailing of long shaft fractures of lower limbs from June 2015 to June 2020. All patients were treated with the original intramedullary nailing and bone grafting from the iliac bone, and were underwent open reduction plate internal fixation and bone grafting for old fractures. Among them, 14 were males and 6 were females, aged from 35 to 56 years old with an average of (42.2±9.6) years old. Nine patients were femoral shaft fracture and 11 patients were tibial shaft fracture. According to characteristics of fracture end nonunion, 6 patients were stable/atrophic, 9 patients were unstable/large, and 5 patients were unstable/atrophic. The nonunion time ranged from 8 to 12 months with an average of(9.8±2.0) months after the initial surgery. Visual analogue scale (VAS), knee range of motion, bone healing time, complications and fracture-end healing were recorded before and at the latest follow-up.@*RESULTS@#All patients were followed up for 18 to 48 months with an average of (36.3±10.5) months. The incision of all patients were healed at stageⅠwithout complications such as infection or internal fixation ruptur. Healing time of femur and tibia was (8.5±2.6) months and (9.5±2.2) months. Knee joint motion increased from preoperative (101.05±8.98) ° to postoperative (139.35±8.78) ° at the latest follow-up (t=-12.845, P<0.001). VAS decreased from preoperative (5.15±1.72) to postoperative (0.75±0.96) at the latest follow-up (t=11.186, P<0.001).@*CONCLUSION@#On the basis of retaining the original intramedullary nail, the addition of locking plate internal fixation and autogenous iliac bone grafting have advantages of simple operation, less trauma, fewer complications and high fracture healing rate. It is one of the effective surgical schemes for the treatment of nonunion after intramedullary nail fixation of long bone fracture of lower extremity.

Proximal tibial lateral locking plate with rafting screws combined with Jail screws in the treatment of collapse fracture of the lateral tibial plateau / 中华创伤杂志

Objective:To explore the efficacy of the proximal tibial lateral locking plate with rafting screws combined with Jail screws in the treatment of collapse fracture of the lateral tibial plateau.Methods:A retrospective case series study was performed on clinical data of 36 patients with collapse fracture of the lateral tibial plateau admitted to Suqian Hospital of Nanjing Drum Tower Hospital Group from January 2016 to January 2020, including 19 males and 17 females, aged 34-68 years [(48.6±5.8)years]. Schatzker classification was type II in 28 patients and type III in 8 patients. All patients were treated using the proximal tibial lateral locking plate with raft screws combined with Jail screws. The operation time, intraoperative blood loss and fracture healing were detected. The distance of articular surface collapse of the tibial plateau, posterior inclination angle (PSA) of the tibial plateau, tibial plateau varus angle (TPVA) and Rasmussen anatomical score were compared before operation and at day 2 and 1 year after operation. The Hospital for Special Surgery (HSS) score was used to evaluate knee function at day 2 and 1 year after operation. Complications were also recorded.Results:All patients were followed up for 12-32 months [(19.5±3.1)months]. The operation time was 56-82 minutes [(68.5±9.1)minutes]. The intraoperative blood loss was 40-100 ml [(75.6±10.2)ml]. The fracture was clinically healed by first-stage, with the healing time of 8 to 15 weeks [(12.5±1.3)weeks]. The distance of articular surface collapse of the tibial plateau was improved from (15.5±4.2)mm before operation to (0.7±0.3)mm at day 2 after operation and (1.0±0.2)mm at 1 year after operation (all P<0.01). The PSA was improved from (21.2±2.1)° before operation to (8.9±0.8)° at day 2 after operation and (9.2±0.6)° at 1 year after operation (all P<0.01). The TPA was improved from (100.2±3.7)° before operation to (88.9±1.8)° at day 2 after operation and (87.2±1.6)° at 1 year after operation (all P<0.05). The Rasmussen anatomical score changed from (7.8±1.8)points before operation to (17.1±0.9)points at day 2 after operation and (16.3±0.7)points at 1 year after operation (all P<0.01). There were no significant difference in the distance of articular surface collapse of the tibial plateau, PSA, TPVA and Rasmussen anatomical score at day 2 and 1 year after operation (all P>0.05). The HSS score was (92.8±3.2)points at 1 year after operation, significantly higher than (74.8±3.5) points at day 2 after operation ( P<0.01). Two patients sustained superficial wound infection after operation, which healed after debridement and dressing change. No deep infection occurred. Conclusion:For patients with collapse fracture of the lateral tibial plateau, the proximal tibial lateral locking plate with rafting screws combined with Jail screws can effectively prevent secondary collapse of the articular surface and obtain satisfactory anatomical reduction, good functional recovery and few postoperative complications.

Vibration Characteristics of Hollow Screws and Locking Plates for Treating Femoral Neck Fractures / 医用生物力学

Objective To investigate the influence from natural and constrained modal of the hip joint on internal fixation after implantation of hollow screws and locking plates for treating femoral neck fractures. Methods CT image data of a patient with femoral neck fracture were analyzed, boundary of the hip joint was extracted to generate a three-dimensional (3D) model of the hip joint, and the assembly of common internal fixation models and hip joint models was established. Finite element simulation was then conducted, with focus on vibration characteristics. Results Vibration had a certain effect on internal fixation stability of hollow screws and locking plates. The occurrence of torsion would destroy the fixation environment of hollow screws and locking plates, resulting in a small displacement at the fracture end. In a constrained state, the modal frequency range was lower. Deformation of the vibration shape mostly occurred at proximal end of the femoral head, leading to the loosening phenomenon of internal fixation and prosthesis. A method for judging the stability of internal fixation was proposed from the perspective of vibration characteristics, and it was found that the stability of internal fixation with hollow screws was better than that of proximal locking plates. Conclusions For choosing internal fixation, influences from natural frequency of the screw and plate should be considered, so as to avoid natural frequency of the femur, which may cause resonance. The results can be used as a guidance for the selection of internal fixation materials and the design of structure and configuration.

Stabilization of dorsal intra-articular fragment in distal radius fracture after volar locking plate fixation / 中华创伤骨科杂志

Objective:To explore the risk factors that may affect the stabilization of dorsal intra-articular fragment in distal radius fracture after volar internal fixation.Methods:A retrospective analysis was performed of the patients with distal radius fracture who had been treated by volar internal fixation at Department of Traumatic Orthopedics, Tongji Hospital Affiliated to Tongji University from July 2016 to July 2020. After 3D reconstruction of their preoperative CT scans by software Mimics 20.0, 66 patients with a dorsal intra-articular fragment were screened out. They were 31 males and 35 females, aged from 23 to 78 years (average, 53.4 years). By the AO classification, there were 17 case of type C1, 22 cases of type C2, and 27 cases of type C3. The displacement of dorsal intra-articular fragment was judged by X-ray observation on postoperative day 2 and X-ray follow-up at the outpatient department. The 13 patients with displacement of dorsal intra-articular fragment>2 mm were assigned into a displacement group while the other 53 ones into a displacement-free group. The 2 groups were compared in terms of preoperative general data and anatomical data of the dorsal intra-articular fragment (total preoperative displacement, radius-ulnar length, dorsal-volar length, aspect ratio, proximal-distal length and volume) to analyze the correlations between them and displacement.Results:There was no significant difference in preoperative general data (age, gender, affected side, cause of injury or AO classification) between the 2 groups, showing comparability between groups ( P>0.05). All patients were followed up for 6 to 24 months (mean, 14 months) after surgery. There were no postoperative complications like neurovascular lesion or infection. None of the patients in the displacement group underwent revision surgery, and the fractures healed successfully during the postoperative follow-up. The total preoperative displacement in the displacement group was(10.0±1.3) mm, significantly larger than that in the displacement-free group [(7.8±1.5) mm]; the radius-ulnar length in the displacement group was (8.2±1.3) mm, significantly shorter than that in the displacement-free group [(10.8±2.3) mm]; the aspect ratio of the fragment in the displacement group was 1.2±0.2, significantly lower than that in the displacement-free group (1.4±0.2); the fragment volume in the displacement group was (690.5± 201.4) mm 3, significantly smaller than that in the displacement-free group [(995.8±295.0) mm 3]. There were significant differences in the above items between the 2 groups ( P<0.05). Conclusion:The total preoperative displacement, radius-ulnar length, aspect ratio and volume of a dorsal intra-articular fragment are important factors which may affect the displacement of the dorsal fragment after volar internal fixation.

The Outcome of Fixing Distal Femur Periprosthetic Fracture around Total Knee Replacement using a Locking Plate Non-Contact Bridging (NCB)

@#Introduction: Surgical fixation of peri-prosthetic distal femur fractures around knee replacements poses a challenge, especially in frail patients, with variable outcomes reported in the literature. This study looks at the outcomes of a consecutive series of patients presenting with such fractures and treated by using a locking plate fixation. Materials and methods: A total of 21 consecutive patients who were admitted to our trauma unit over 31 months and underwent fixation with the Non-Contact Polyaxial Locking plate system were retrospectively identified and their acute treatment with follow-up outcomes were analysed. Results: The mean age was 81 years and 71% were in ASA grades 3 and 4. Fracture morphologies were classified as per the Su classification, yielding 8 (38%) classified as Su one, 4 (19%) as Su two, and 9 (43%) as Su type three. Postoperatively, 2 patients (9.5%) died due to hospital-acquired pneumonia, and another 2 patients (9.5%) developed wound infections necessitating further return to theatre. Additionally, 2 (9.5%) patients had distal femoral replacements due to non-union. Mean discharge time was 28 days with 12 patients (55% of patients) starting protected weight-bearing six weeks after surgery. Conclusion: The incidence of morbidity, mortality was significant and re-operation was required in patients treated as described, and these were partly attributed to the patient’s average age and the pre-existing comorbidities. Significant variations were noted in the time to discharge, rehabilitation, and time to achieve fracture union. However, the majority of fractures did eventually unite. Patients with comminuted fractures and insufficient bone stock are more likely to progress to non-union and end up requiring revision knee arthroplasty.

Research of Building 3D Model in External Fixator for Proximal Femoral Fracture Based on Locking Plate Shape / 中国医疗器械杂志

The software of 3D-Modeling(UG NX 10.0) was used to design a new external fixator model for proximal femoral fracture, and fresh femoral cadaver specimens were used to simulate experimental operation. The results showed that the external fixator designed with the proximal femoral locking plate shape can improve the accuracy of Kirschner wire penetration into the femoral neck, reduce fluoroscopic and soft tissue incision injuries, and make a good stability and is easy to operate, which has a certain value for patients with proximal femoral fracture, such as intolerant surgery and poor physical condition.

Subtalar arthroscopy combined with locking plate fixation through anterolateral longitudinal incision of the Achilles tendon for treatment of displaced intra-articular calcaneal fractures / 中华创伤杂志

Methods:A retrospective case-series study was performed to analyzed the data of 38 patients (38 feet) with displaced intra-articular calcaneal fractures admitted to Xuzhou Central Hospital from January 2016 to May 2018. There were 21 males (21 feet) and 17 females (17 feet), with the age of (33.7±6.2)years (range, 21-53 years). According to the Sanders' classification, 7 patients were classified as type II, 27 as type III and 4 as type IV. All patients underwent the procedure of subtalar arthroscopy combined with locking plate fixation through anterolateral longitudinal incision of the Achilles tendon procedure. The operation time, intro-operative management, incision healing, and post-operative complications (nerve, vessels and tendon injuries)were recorded. B?hler angle, Gissane angle, length, width and height of the calcaneus, and bone healing time were recorded at postoperative 2 days and at final follow-up. The visual analogue score (VAS), American Orthopaedic Foot & Ankle Society (AOFAS) ankle and hindfoot scale, and Foot and Ankle Outcome Score (FAOS) were recorded at final follow-up, and were used to evaluate the clinical and functional outcomes.Results:All patients were followed up for 12-42 months [(18.7±5.3)months]. The operation time ranged from 45 to 100 minutes [(72.4±22.6)minutes]. Bone grafting was not observed, and microfracture of the posterior articular surface of the calcaneus were involved in 9 patients. The first-stage incision healing was achieved in all patients, without early complications of nerve, vessel and tendon injuries. The post-operative angles of B?hler and Gissane, length, width and height of the calcaneus were significantly improved compared to preoperative values ( P<0.01), while there were no significant difference at postoperative 2 days and at final follow-up ( P>0.05). At final follow-up, the VAS decreased from 5(3, 9)points to 0(0, 3)points, AOFAS improved from (68.3±10.5)points to (90.6±5.0)points, and FAOS improved from (66.9±9.1)points to (89.8±4.3)points, respectively ( P<0.01). According to the AOFAS ankle and hindfoot scale, the result was excellent in 27 patients, good in 8, and fair in 3, with the excellent and good rate of 92%. Conclusions:For displaced intra-articular calcaneal fractures, subtalar arthroscopy combined with locking plate fixation through anterolateral longitudinal incision of the Achilles tendon has advantages of precise fracture reduction, low postoperative complications and reliable functional outcomes.

Minimally invasive three-window incision and novel anatomical locking plate for treatment of calcaneal fractures / 中华创伤骨科杂志

Objective:To investigate the efficacy of a minimally invasive three-window incision and internal fixation with a novel anatomical locking plate in the treatment of calcaneal fractures.Methods:A retrospective analysis was performed of the 46 patients with calcaneal fracture (Sanders typeⅡ and Ⅲ) who had been admitted to Department of Orthopedics, Luoyang Orthopaedic Hospital of Henan Province from February 2015 to May 2017. They were 22 males and 24 females, aged from 19 to 59 years (average, 39.0 years) and with 16 left and 30 right sides affected. They were all treated with a minimally invasive three-window incision and internal fixation with a novel anatomic locking plate. Their B?hler and Gissane angles, and height, width and length of the calcaneus were compared between preoperation, immediate postoperation and the last follow-up. Their ankle-hindfoot functions were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) scoring scale at the last follow-up; their complications were recorded.Results:All the 46 patients were followed up immediately after operation and for 14 to 18 months (mean, 16 months). All the fractures achieved bony union after an average of 3 months (from 2 to 4 months). At immediate postoperation and at the last follow-up, their calcaneal B?hler angles (34.20°±3.62° and 34.05°±3.65°) and Gissane angles (131.45°±6.04° and 131.25°±5.88°), and calcaneal heights [(41.05±2.76) mm and (40.90±2.86) mm], widths [(25.65±1.53) mm and (25.55±1.64) mm] and lengths [(76.82±1.70) mm and (76.73±1.78) mm] were significantly improved compared with the preoperative values [10.55°±7.51°, 95.32°±12.16°, (26.10±4.54) mm, (37.71±3.42) mm and (65.91±2.10) mm] ( P<0.05). There were no significant differences in the above indexes between immediate postoperation and the last follow-up ( P>0.05). According to AOFAS ankle-hindfoot scores at the last follow-up, the efficacy was evaluated as excellent in 28 cases, as good in 12 cases and as fair in 6 cases, yielding an excellent and good rate of 87.0%. No incision infection occurred after operation. Conclusion:In the treatment of calcaneal fractures of Sanders type Ⅱ and Ⅲ, the minimally invasive three-window incision and internal fixation with the novel calcaneal anatomical locking plate can achieve satisfactory reduction and rigid fixation, effectively reducing postoperative incision complications.