Finite element analysis of femoral neck fracture treated by internal fixation of femoral neck system under nonanatomical reduction / 中国组织工程研究

BACKGROUND:Irreducible femoral neck fracture was difficult to obtain anatomic reduction.As a new type of internal fixation,the femoral neck system is still blank for the treatment of non-anatomical reduced femoral neck fractures. OBJECTIVE:To explore the biomechanical stability of femoral neck system internal fixation under nonanatomical reduction in the treatment of femoral neck fractures based on finite element analysis. METHODS:CT data of the hip joint of a healthy female adult were obtained.Anatomical reduction of femoral neck fracture models with Pauwels angles of 30°,50°,and 70° were established using Mimics 21.0,Geomagic Wrap 2021,and SolidWorks 2020.The fracture proximal ends of the three anatomical reduction models were shifted upward by 2 mm along the fracture line,and three positive buttress models with different Pauwels angles were obtained.In the same way,three negative buttress models were acquired by shifting downward by 2 mm.SolidWorks 2020 was used to make the femoral neck system internal fixation,and the nine femoral neck fracture models were assembled with the femoral neck system.Then Ansys 19.0 was used for finite element analysis.The displacement distribution and maximum displacement,stress distribution and maximum stress of the femur and femoral neck system were recorded under 2100 N stress. RESULTS AND CONCLUSION:(1)When Pauwels angles were 30°,50°,and 70°,the maximum stresses of the femoral neck system appeared to be concentrated at the junction of the sliding hip screw and anti-rotation screw.The maximum femur stresses appeared to be concentrated in the medial cortex of the femur.The maximum displacement was concentrated at the upper of the femoral head and femoral neck system.(2)When Pauwels angles were 30° and 50°,the maximum displacement and maximum stress of the femoral neck system and femur were:negative buttress>anatomical reduction>positive buttress.(3)When Pauwels angle was 70°,the maximum displacement and maximum stress of the femoral neck system were:negative buttress>anatomical reduction>positive buttress;the maximum displacement and maximum stress of the femur were:negative buttress>positive buttress>anatomical reduction.(4)With the increase of Pauwels angle,the biomechanical advantage of the positive buttress was weakening.However,it was better than a negative buttress.When Pauwels angle was 30°,positive buttress was more stable than anatomical reduction.When Pauwels angle was 50°,the biomechanical difference between positive buttress and anatomical reduction became smaller.When Pauwels angle was 70°,the stability of anatomical reduction was slightly better than positive buttress.(5)If it was difficult to achieve anatomical reduction of femoral neck fracture during operation,but the positive buttress had been displaced within 2 mm,the femoral neck system could be used to offer stable mechanical fixation.It is necessary to avoid negative buttress reduction.

Inverted triangle cannulated screw assisted transverse lag screw and femoral neck system fixation for Pauwels Ⅲ femoral neck fractures / 中国组织工程研究

BACKGROUND:Pauwels Ⅲ femoral neck fracture is a typical unstable fracture characterized by high vertical shear force and high incidence of postoperative complications.At present,there are many fixation methods for Pauwels Ⅲ fracture,and there is no clear conclusion as to which internal fixation is the best fixation method for Pauwels Ⅲ femoral neck fracture in young adults. OBJECTIVE:To compare the clinical effect of three inverted triangle cannulated screws assisted transverse lag screws and femoral neck system in fixing Pauwels Ⅲ femoral neck fractures of young adults. METHODS:From May 2021 to December 2022,21 young and middle-aged patients with Pauwels Ⅲ femoral neck fracture were treated with three inverted triangle cannulated screws assisted by transverse lag screws and femoral neck system in Affiliated Hospital of Southwest Medical University.Of them,9 patients were treated with three inverted triangle cannulated screws and one transverse lag screws perpendicular to the fracture line as the 3+1 cannulated screw group and 12 patients were treated with femoral neck system as the femoral neck system group.The two fixation methods were compared in terms of operation time,intraoperative blood loss,total incision length,intraoperative fluoroscopy times,fracture healing time,and limb function. RESULTS AND CONCLUSION:(1)All patients were followed up.Patients in the 3+1 cannulated screw group were followed up for 10-25 months,with a mean of(17.44±4.30)months.The patients in the femoral neck system group were followed up for 8-24 months,with a mean of(15.58±4.68)months.(2)The intraoperative fluoroscopy times and Harris score at 3 months postoperatively in the femoral neck system group were better than those in the 3+1 cannulated screw group,and the difference was statistically significant(P<0.05).The intraoperative blood loss,total incision length,and femoral neck shortening distance in the 3+1 cannulated screw group were better than those in the femoral neck system group,and the differences were statistically significant(P<0.05).There was no significant difference in operation time,fracture healing time,and Harris score at the last follow-up between the two groups(P>0.05).(3)It is indicated that three inverted triangle cannulated screws assisted transverse lag screw and femoral neck system can achieve good clinical effects in the treatment of young and middle-aged Pauwels Ⅲ femoral neck fracture.The femoral neck system has fewer intraoperative fluoroscopy times and better early overall stability,while the 3+1 cannulated screw is more minimally invasive,easier to operate.Both fixation methods are worthy of clinical application and promotion,and can be selected according to the actual clinical situation.

Comparison of femoral neck system and cannulated compression screws in the fixation of femoral neck fractures in the elderly patients aged 65 to 75 years old / 中华创伤骨科杂志

Objective:To compare the therapeutic efficacy between femoral neck system (FNS) and cannulated compression screws (CCS) in the fixation of femoral neck fractures in the elderly patients aged 65 to 75 years old.Methods:A retrospective study was conducted to analyze the data of 39 patients aged 65 to 75 years old who had been treated for femoral neck fractures at Department of Trauma Surgery, Hospital Affiliated to Qingdao University from January 2015 to September 2022. The patients were divided into 2 groups according to their internal fixation methods. In the FNS group of 18 cases subjected to FNS fixation, there were 8 male and 10 females with an age of (71.1±2.8) years. In the CCS group of 21 cases subjected to CCS fixation, there were 7 males and 14 females with an age of (70.1±2.9) years. The 2 groups were compared in terms of intraoperative fluoroscopy frequency, surgical time, intraoperative bleeding, hospitalization costs, fracture healing time, internal fixation failure, and Harris hip score, changes in neck shaft angle, and femoral neck shortening at 1 year after surgery.Results:The differences were not statistically significant in the preoperative general data or follow-up time between the 2 groups, indicating comparability ( P>0.05). In the FNS group, the intraoperative fluoroscopy frequency [(15.1±2.3) times] was significantly lower than that in the CCS group [(19.5±3.5) times], the surgical time [(49.2±5.2) minutes] was significantly shorter than that in CCS group [(62.4±11.2) minutes], and the intraoperative bleeding [(74.2±15.6) mL] and hospitalization costs [(39,928.7±1,438.3) yuan] were significantly higher than those in the CCS group [(53.1±17.3) mL and (23,527.9±2,126.3) yuan] (all P<0.05). The difference in fracture healing time was not statistically significant between the 2 groups ( P>0.05). In the FNS group, the decreased neck shaft angle (2.65°±1.66°) and femoral neck shortening (3.9±1.3 mm) were significantly smaller than those in the CCS group [4.18°±2.13° and (6.3±2.5) mm] at 1 year after surgery, and the Harris hip score [(82.2±7.2) points] was significantly higher than that in the CCS group [(76.4±5.9) points] (all P<0.05). Internal fixation failure occurred in 1 case in the FNS group and in 4 cases in the CCS group, respectively, showing no statistically significant difference ( P>0.05). Conclusions:Compared with CCS fixation, FNS fixation may lead to better therapeutic efficacy in patients with femoral neck fracture aged 65 to 75 years old. However, the risk of internal fixation failure should also be taken into consideration.

Biomechanical analysis of four internal fixations for Pauwels Ⅲ femoral neck fractures with defects / 中国骨伤

OBJECTIVE@#To investigate the biomechanical characteristics of different internal fixations for Pauwels type Ⅲ femoral neck fracture with defect, and provide reference for the treatment of femoral neck fracture.@*METHODS@#Three-dimensional (3D) finite element models of femoral neck fractures were established based on CT images, including fracture and fracture with defects. Four internal fixations were simulated, namely, inverted cannulated screw(ICS), ICS combined with medial buttress plate, the femoral neck system (FNS) and FNS combined with medial buttress plate. The von Mises stress, model stiffness and fracture displacements of fracture models under 2 100 N axial loads were measured and compared.@*RESULTS@#When femoral neck fracture was fixed by ICS and FNS, the peak stress was mainly concentrated on the surface of the screw near the fracture line, and the peak stress of FNS is higher than that of ICS;When the medial buttress plate was combined, the peak stress was increased and transferred to medial buttress plate, with more obvious of ICS fixation. For the same fracture model, the stiffness of FNS was higher than that of ICS. Compared with femoral neck fracture with defects, fracture model showed higher stiffness in the same internal fixation. The use of medial buttress plate increased model stiffness, but ICS increased more than FNS. The fracture displacement of ICS model exceeded that of FNS.@*CONCLUSION@#For Pauwels type Ⅲ femoral neck fracture with defects, FNS had better biomechanical properties than ICS. ICS combined with medial buttress plate can better enhance fixation stability and non-locking plate is recommended. FNS had the capability of shear resistance and needn't combine with medial buttress plate.

Short term follow-up of unstable femoral neck fractures in young adults treated with femoral neck system and cannulated compression screws / 中国骨伤

OBJECTIVE@#To investigate the clinical efficacy of femoral neck system(FNS) and three cannulated compression screws(CCS) in the treatment of unstable femoral neck fractures in young adults.@*METHODS@#The clinical data of 52 young and middle-aged patients with unstable femoral neck fractures admitted from August 2018 to August 2021 were reviewed and analyzed. All patients were divided into two groups according to the internal fixation method, 25 cases were treated with FNS fixation, 27 cases were treated with closed reduction and 3 CCS inverted triangular distribution. The operation time, incision length, intraoperative bleeding, hospitalization expenses and fracture reduction quality of two groups were recorded and compared;The patients were followed up regularly after operation. The fracture healing time, complete weight-bearing time and postoperative complications(nonunion, femoral neck shortening, femoral head necrosis) of two groups were compared. The Harris score was used to evaluate hip function 6 months after surgery.@*RESULTS@#The operation was successfully completed in both groups. The patients in FNS group had more bleeding, longer incision length and higher hospitalization cost than CCS group(P<0.01). There ware no significant difference in operation time and Garden index between two groups(P>0.05). Patients in both groups were followed up for 6 to 32 months.The fracture healing time in FNS group was less than that in CCS group, the time of complete weight bearing after surgery was earlier than that in CCS group, and the hip Harris score was higher than that in CCS group (P<0.01). There were no internal fixation fracture complications in two groups during follow-up. In the FNS group, there were 4 cases of avascular necrosis of the femoral head and 2 cases of femoral neck shortening, of which 3 cases underwent total hip replacement due to avascular necrosis of the femoral head. In the CCS group, there were 2 cases of nonunion, 9 cases of avascular necrosis of the femoral head, and 11 cases of femoral neck shortening, among which 5 cases underwent total hip replacement due to nonunion and avascular necrosis of the femoral head.@*CONCLUSION@#With simple operation, rotational stability and angular stability, FNS enables patients to start functional exercise as early as possible and reduces the incidence of postoperative complications of unstable femoral neck fracture. It is a new choice for the treatment of unstable femoral neck fracture in young adults.

Femoral neck system and cannulated compression screw fixation in the treatment of femoral neck fracture in the young and middle-aged patients: efficacy comparison / 中华创伤杂志

Objective:To compare the efficacy of femoral neck system (FNS) and cannulated compression screw (CCS) in the treatment of femoral neck fracture in the young and middle-aged patients.Methods:A retrospective cohort study was conducted to analyze the clinical data of 91 patients with femoral neck fracture admitted to Fuzhou Second Hospital from July 2020 to December 2021, including 52 males and 39 females; aged 23-65 years [(48.9±10.3)years]. Garden classification of the fracture found that 31 patients were with type I, 9 with type II, 12 with type III and 39 with type IV. Pauwels classification of the fracture found that 7 patients were with type I, 33 with type II and 51 with type III. A total of 53 patients were treated with FNS fixation (FNS group) and 38 patients with CCS fixation (CCS group). The operation time, intraoperative blood loss, Haidukewych fracture reduction quality, hospitalization time, Barthel index, fracture healing time, and weight-bearing time were compared between the two groups. The hip function was assessed by Harris hip score in both groups at postoperative 3 months, 6 months and 1 year and at the final follow-up. The incidences of postoperative complication and secondary surgery were also compared between the two groups.Results:All the patients were followed up for 15-31 months [(22.2±5.5)months]. There were no significant differences in the operation time, Haidukewych fracture reduction quality, hospitalization time, or Barthel index (all P>0.05). The intraoperative blood loss in the FNS group was 50.0(20.0,85.0)ml, which was more than that in the CCS group [20.0(10.0,50.0)ml] ( P<0.01). The fracture healing time, partial weight-bearing time, and full weight-bearing time in the FNS group [4.0(3.0,5.0)months, 3.0(2.0,3.0)months, 5.0(4.5,6.0)months] were shorter than those in the CCS group [6.0(5.0,7.0)months, 3.0(2.8,4.0)months, 6.0(6.0,7.0)months] (all P<0.01). The Harris hip score at postoperative 3 months, 6 months and 1 year and at the final follow-up were 74.0(71.0,77.0)points, 87.0(84.0,88.5)points, 91.0(88.0,95.0)points, and 94.0(91.0,96.0)points in the FNS group, significantly higher than those in the CCS group [73.0(70.0,74.0)points, 82.5(79.8,87.0)points, 88.0(83.5,91.0)points, 89.0(84.0,93.0)points] (all P<0.05 or 0.01). There were no statistically significant differences in the incidences of postoperative complication or secondary surgery between the two groups (all P>0.05). Conclusion:Compared with CCS, FNS can shorten fracture healing time, allow patients to carry full weight as soon as possible, and significantly improve hip function in the treatment of middle-aged and young adults with femoral neck fracture, although there is more intraoperative blood loss.

Early effectiveness of Ti-Robot assisted femoral neck system for minimally invasive treatment of elderly Garden type Ⅱ and Ⅲ femoral neck fractures / 中国修复重建外科杂志

OBJECTIVE@#To investigate the early effectiveness of the Ti-Robot assisted femoral neck system (FNS) in the treatment of elderly Garden type Ⅱ and Ⅲ femoral neck fractures.@*METHODS@#A retrospective analysis was conducted on the clinical data of 41 elderly patients with Garden type Ⅱ and Ⅲ femoral neck fractures who were admitted between December 2019 and August 2022 and met the selection criteria. Among them, 21 cases were treated with Ti-Robot assisted FNS internal fixation (study group), and 20 cases were treated solely with FNS internal fixation (control group). There was no significant difference in baseline data, including gender, age, side, cause of injury, time from injury to surgery, fracture Garden classification, and fracture line classification, between the two groups ( P>0.05). Surgical effectiveness was evaluated based on parameters such as operation time (including incision time and total operation time), reduction level, number of dominant pin insertions, intraoperative fluoroscopy frequency, incision length, whether to extend the incision, need for assisted reduction, postoperative hospital stay, fracture healing time, incidence of osteonecrosis of the femoral head, postoperative visual analogue scale (VAS) score at 1 day, and Harris hip score at last follow-up.@*RESULTS@#The study group showed significantly shorter incision time, fewer dominant pin insertions, fewer instances of extended incisions, fewer intraoperative fluoroscopy frequency, and smaller incisions than the control group ( P<0.05). There was no significant difference in total operation time, reduction level, and assisted reduction frequency between the two groups ( P>0.05). Both groups achieved primary wound healing postoperatively, with no complications such as incision leakage or skin infection. All patients were followed up 12-24 months with an average of 14.6 months. Fractures healed in both groups, with no significant difference in healing time ( P>0.05). There was no significant difference in postoperative hospital stay between the two groups ( P>0.05). The study group showed significantly better VAS score at 1 day after operation and Harris hip score at last follow-up when compared to the control group ( P<0.05). No complication such as internal fixation failure, fracture displacement, or hip joint varus occurred in both groups during the follow-up. Osteonecrosis of the femoral head occurred in 1 patient of the control group, while no was observed in the study group, and the difference in the incidence of osteonecrosis of the femoral head between the two groups was not significant ( P=0.488).@*CONCLUSION@#Compared to sole FNS internal fixation treatment, Ti-Robot assisted FNS internal fixation for elderly Garden typeⅡ and Ⅲ femoral neck fractures can reduce incision time, achieve minimally invasive and accurate nail implantation, and decrease intraoperative fluoroscopy frequency, leading to improved postoperative hip joint function recovery.

Risk factors for moderate and severe femoral neck shortening in displaced femoral neck fractures following treatment by a femoral neck system / 中华创伤骨科杂志

Objective:To investigate the incidence of and risk factors for femoral neck shortening in young and middle-aged patients with displaced femoral neck fracture treated by a femoral neck system (FNS).Methods:A retrospective study was conducted to analyze the clinical data of 135 patients with displaced femoral neck fracture who had been treated by closed reduction and FNS internal fixation at Department of Orthopaedics, The Second Hospital of Fuzhou from December 2019 to December 2021. There were 85 males and 50 females, with an age of 51 (42, 57) years and a body mass index of 22.6 (20.9, 24.2) kg/m 2. According to the Garden classification, there were 29 cases of type Ⅲ and 106 cases of type Ⅳ. Femoral neck shortening was observed. The patients' gender, age, side of shortening, body mass index, fracture type, high-energy injury, time from injury to surgery, cortical comminution at the fracture end, reduction quality (Garden index), partial weight bearing time, complete weight bearing time, and functional evaluation (Harris score) were recorded for a univariate analysis. Multivariate logistic regression was used to analyze the influencing factors for moderate to severe shortening. Results:All the 135 patients were followed up for 17.2 (15.0, 20.2) months. Different degrees of femoral neck shortening happened in all patients, yielding an incidence of 100%(135/135). The femoral neck shortening was 4.2 (2.6, 7.7) mm in displaced femoral neck fractures fixated by FNS. The shortening continued to worsen within the first 3 months after operation, reaching a stable state in the first 6 months. Persistent shortening hardly occurred after 6 months. According to the shortening distance, the patients were divided into a mild shortening group (76 cases <5 mm) and a moderate to severe shortening group (59 cases ≥ 5 mm). The Harris score at the last follow-up in the mild shortening group (91.7 ± 2.3) was significantly higher than that in the moderate to severe shortening group (87.9 ± 3.8) ( P<0.001). The fracture healing rate was 98.7% (75/76) in the mild shortening group and 98.3% (58/59) in the moderate to severe shortening group, showing no significant difference ( P=1.000). Logistic regression analysis found that the risk factors for moderate to severe shortening were fracture type (type Ⅳ) ( OR = 10.227, 95% CI: 1.845 to 56.693, P = 0.008), cortical comminution at the fracture end (if present) ( OR=52.697, 95% CI: 9.870 to 281.352, P<0.001), and partial weight bearing time <4 weeks ( OR = 0.168, 95% CI: 0.032 to 0.893, P = 0.036). Conclusions:The incidence of femoral neck shortening may be high in young and middle-aged patients with displaced femoral neck fracture treated by FNS, leading to decreased hip function. The main risk factors for femoral neck shortening are fracture type (Garden type Ⅳ), cortical comminution at the fracture end and partial weight-bearing time less than 4 weeks.

Comparison of a bidirectional-traction reduction device versus a traction table in treatment of femoral neck fractures with femoral neck system / 中华创伤骨科杂志

Objective:To compare the clinical efficacy between a bidirectional-traction reduction device and a traction table in the treatment of femoral neck fracture with femoral neck system (FNS).Methods:A retrospective study was conducted in the 46 patients with femoral neck fracture who had been treated at Department of Orthopedics, The First Central Hospital of Baoding from January 2020 to January 2021. There were 19 males and 27 females, aged from 30 to 64 years (average, 47.1 years). According to the Garden classification, 29 cases were type Ⅲ and 17 type Ⅳ. By the reduction method, the patients were assigned into an observation group ( n=24) in which the reduction was assisted by a bidirectional-traction reduction device and a control group ( n=22) in which the reduction was assisted by a traction table. FNS fixation was conducted in both groups. The 2 groups were compared in terms of operation time, reduction time, fluoroscopy frequency, intraoperative blood loss, femoral neck shortening at immediate postoperation and 12 months postoperation, Harris scores of the affected hip at 3, 6, and 12 months postoperation, and incidence of lower extremity venous thrombosis. Results:There were no significant differences in age, gender or fracture type between the 2 groups, showing they were comparable ( P>0.05). The observation group needed significantly less operation time [57.5 (54.0, 64.5) min], reduction time [(16.3±3.0) min] and fluoroscopy frequency [(20.5±4.6) times] than the control group did [85.0 (71.3, 92.0) min, (21.0±6.0) min and (29.7±4.7) times, respectively] (all P<0.05). There was no significant difference in intraoperative blood loss between 2 groups ( P>0.05). All patients were followed up for 12 to 22 months (average, 15.5 months). There was no significant difference in femoral neck shortening between the 2 groups at immediate postoperation or 12 months postoperation ( P>0.05). The Harris score of the affected hip in the observation group was significantly better than that in the control group at 3 months after surgery ( P<0.05), but such a significant difference was not observed at 6 or 12 months postoperation ( P>0.05). The incidence of thrombotic complications in the observation group (12.5%, 3/24) was significantly lower than that in the control group (40.9%, 9/22) ( P<0.05). Conclusions:In the FNS treatment of femoral neck fracture, compared with a traction table, reduction assisted by a bidirectional-traction reduction device is more advantageous because it is simpler and less time-consuming, incurs less fluoroscopy and leads to better early functional recovery of the affected hip and lower incidence of thrombotic complications.

Comparison of short-term efficacy between femoral neck system and cannulated compression screws in treatment of femoral neck fractures / 中华创伤骨科杂志

Objective:To compare the short-term efficacy between femoral neck system (FNS) and cannulated compression screws (CCS) in the treatment of femoral neck fractures in young and middle-aged patients.Methods:A retrospective study was performed of the 29 young and middle-aged patients with femoral neck fracture who had been treated with FNS at Department of Orthopaedics and Traumatology, Beijing Jishuitan Hospital from January 2020 to December 2020. A control group of another 29 patients with femoral neck fracture was selected who had been treated with CCS but matched in gender, age, and body mass index. In the CCS group, there were 14 males and 15 females with an age of (48.2±12.3) years; in the FNS group, there were 14 males and 15 females with an age of (48.2±12.0) years. The fracture reduction quality, operation time, intraoperative blood loss, and femoral neck shortening, hip joint function, Barthel index and health survey 12-item short form (SF-12) score at the last follow-up and complications during follow-up were compared between the 2 groups.Results:No significant difference was found in the preoperative general data or follow-up time between the 2 groups, showing comparability ( P>0.05). The intraoperative blood loss in the CCS group [20 (10, 50) mL] was significantly less than that in the FNS group [50 (20, 50) mL], and the femoral neck shortening at the last follow-up in the CCS group (grade 1 in 5 cases; grade 2 in 18 cases and grade 3 in 6 cases) was significantly worse than that in the FNS group (grade 1 in 21 cases, grade 2 in 6 cases and grade 3 in 2 cases) ( P<0.05). No significant difference was found regarding fracture reduction quality, operation time, complications during follow-up, or Merle D'Aubigne Postel score, Barthel index or SF-12 score at the last follow-up ( P>0.05). Conclusions:In the treatment of femoral neck fractures in young and middle-aged patients, both FNS and CCS are good options for internal fixation. However, FNS can reduce the severity of femoral neck shortening and maintain the length of femoral neck better than CCS.

A comparative study of femoral neck system versus inverted triangle cannulated compression screws in fixation of adult femoral neck fracture / 中华创伤骨科杂志

Objective:To compare the clinical efficacy between femoral neck system (FNS) and inverted cannulated compression screws (ICCS) in the fixation of adult femoral neck fracture.Methods:The clinical data were retrospectively analyzed of the 119 patients with femoral neck fracture who had received FNS or ICCS internal fixation at Department of Traumatic Orthopedics, West China Hospital from September 2019 to June 2020. They were divided into 2 groups according to their internal fixation methods. In the FNS group of 62 patients, there were 38 males and 24 females, with an age of (54.0±13.0) years, and 13 cases of type Ⅱ, 34 cases of type Ⅲ and 15 cases of type Ⅳ according to the Garden classification; in the ICCS group of 57 patients, there were 42 males and 15 females, with an age of (53.2±11.3) years, and 9 cases of type Ⅱ, 33 cases of type Ⅲ and 15 cases of type Ⅳ according to the Garden classification. The operation time, intraoperative blood loss, fluoroscopy frequency, hospitalization time, fracture healing time, Harris hip score and incidence of complications were compared between the 2 groups.Results:The 2 groups were comparable due to insignificant differences in their preoperative general data or follow-up duration ( P>0.05). There were significant differences between the FNS and ICCS groups in fluoroscopy frequency [(8.8±2.9) times versus (15.6±3.4) times], operation time [(45.2±10.1) min versus (51.8±11.7) min], fracture healing time [(3.2±0.4) months versus (4.0±0.6) months], Harris hip score at the last follow-up [(91.8±4.4) points versus (84.6±3.3) points], and femoral neck shortening at the last follow-up, favoring the FNS group (all P<0.05). There were no significant differences in follow-up time, hospitalization time, intraoperative blood loss or incidence of complications between the 2 groups ( P>0.05). Conclusions:In the fixation of adult femoral neck fractures, compared with ICCS, FNS can significantly reduce fluoroscopy frequency, shorten fracture healing and operation time, reduce risk of femoral neck shortening and hospitalization time, and promote functional recovery of the hip.

Short-term outcomes of femoral neck system versus dynamic hip screws in treatment of femoral neck fractures / 中华创伤骨科杂志

Objective:To compare the short-term outcomes of femoral neck system (FNS) and dynamic hip screw (DHS) in the treatment of femoral neck fractures.Methods:A retrospective analysis was performed of the 105 patients with fresh femoral neck fracture who had been treated by FNS fixation from September 2019 to October 2020 or by DHS fixation from January 2018 to October 2020 at Department of Orthopaedics, The Third Hospital Affiliated to Peking University. In the FNS group of 54 cases, there were 18 males and 36 females with a mean age of (60.7±15.2) years; in the DHS group of 51 cases, there were 14 males and 37 females with a mean age of (63.3±13.2) years. The 2 groups were compared in terms of hospital stay, operation time, intraoperative blood loss, incision length, intraoperative fluoroscopy frequency, qualify of reduction, and femoral neck shortening length, Harris hip score and complications at the last follow-up.Results:The 2 groups were comparable due to insignificant differences in their preoperative general data or follow-up time ( P>0.05). In the FNS group, the median operation time [45.0 (40.0, 59.0) min], intraoperative blood loss [30.0 (20.0, 50.0) mL], incision length [4.0 (4.0, 5.0) cm], intraoperative fluoroscopy frequency [10.5 (9.0, 12.0) times] and hospital stay [2.0 (2.0, 4.0) d] were significantly superior to those in the DHS group [72.0 (55.0, 89.0) min, 50.0 (30.0, 50.0) mL, 7.0 (6.0, 8.0) cm, 18.0 (15.0, 19.0) times, and 3.0 (3.0, 6.0) d] (all P<0.05). There were no statistical differences between the 2 groups in quality of reduction, length of femoral neck shortening, failure rate of internal fixation or Harris hip score at the last follow-up ( P>0.05). There were no such surgical complications as deep infection or femoral head necrosis in either of the 2 groups. Conclusions:In the fixation of femoral neck fractures, both FNS and DHS may lead to fine short-term outcomes. However, compared with DHS, FNS exhibits advantages of simplicity, minimal invasion, less surgical trauma and intraoperative fluoroscopy frequency, and reduced operation time and hospital stay.

Short-term clinical efficacy of femoral neck system for treatment of femoral neck fractures in young and middle-aged patients / 中华创伤骨科杂志

Objective:To evaluate short-term clinical efficacy of femoral neck system (FNS) for treatment of femoral neck fractures in young and middle-aged patients.Methods:A retrospective analysis was conducted of the 70 middle-aged and young patients who had been surgically treated for femoral neck fractures at Department of Trauma Orthopaedics, Honghui Hospital from January to November 2020. Of them, 32 cases were fixated by FNS; they were 16 males and 16 females, with an age of (49.4±11.0) years, including 10 cases of type Ⅱ, 12 cases of type Ⅲ and 10 cases of type Ⅳ by the Garden classification. The other 38 patients were fixated by cannulated compression screws (CCS); they were 19 males and 19 females, with an age of (48.8±10.1) years, including 12 cases of type Ⅱ, 15 cases of type Ⅲ and 11 cases of type Ⅳ by the Garden classification. The 2 groups were compared in terms of operation time, intraoperative blood loss, fracture reduction, fracture union time, weight-bearing time, complications, Barthel index at 3 months after surgery, and hip function at 6 months after surgery.Results:There was no statistically significant difference in preoperative general information or follow-up time between the 2 groups, showing comparability between groups ( P>0.05). There was no significant difference in operation time, intraoperative blood loss or fracture reduction quality between the 2 groups ( P>0.05). In the FNS group, weight-bearing time [(11.4±3.4) weeks] and fracture healing time [(3.1±0.9) months] were significantly shorter than those in the CCS group [(16.4±3.9) weeks and (3.6±0.9) months], rate of complications (12.5%, 4/32) was significantly lower than that in the CCS group (34.2%, 13/38), Barthel index at 3 months after operation (98.1±2.8) and Harris hip score at 6 months after operation (96.8±4.0) were significantly higher than those in the CCS group (93.8±4.1 and 93.6±6.7) ( P<0.05). Conclusion:In the treatment of femoral neck fractures in young and middle-aged patients, compared with CCS fixation, FNS fixation can obtain better short-term curative effects, due to its advantages of shorter bone union and weight-bearing time, a decreased rate of complications and early functional recovery of daily activities.