Derotation Screw Research Articles

Finite Element Analysis of Six Internal Fixations in the Treatment of Pauwels Type III Femoral Neck Fracture.

The current investigation sought to utilize finite element analysis to replicate the biomechanical effects of different fixation methods, with the objective of establishing a theoretical framework for the optimal choice of modalities in managing Pauwels type III femoral neck fractures. The Pauwels type III fracture configuration, characterized by angles of 70°, was simulated in conjunction with six distinct internal fixation methods, including cannulated compression screw (CCS), dynamic hip screw (DHS), DHS with de-rotational screw (DS), CCS with medial buttress plate (MBP), proximal femoral nail anti-rotation (PFNA), and femoral neck system (FNS). These models were developed and refined using Geomagic and SolidWorks software. Subsequently, finite element analysis was conducted utilizing Ansys software, incorporating axial loading, torsional loading, yield loading and cyclic loading. Under axial loading conditions, the peak stress values for internal fixation and the femur were found to be highest for CCS (454.4; 215.4 MPa) and CCS + MBP (797.2; 284.2 MPa), respectively. The corresponding maximum and minimum displacements for internal fixation were recorded as 6.65 mm for CCS and 6.44 mm for CCS + MBP. When subjected to torsional loading, the peak stress values for internal fixation were highest for CCS + MBP (153.6 MPa) and DHS + DS (72.8 MPa), while for the femur, the maximum and minimum peak stress values were observed for CCS + MBP (119.3 MPa) and FNS (17.6 MPa), respectively. Furthermore, the maximum and minimum displacements for internal fixation were measured as 0.249 mm for CCS + MBP and 0.205 mm for PFNA. Additionally, all six internal fixation models showed excellent performance in terms of yield load and fatigue life. CCS + MBP had the best initial mechanical stability in treatment for Pauwels type III fracture. However, the MBP was found to be more susceptible to shear stress, potentially increasing the risk of plate breakage. Furthermore, the DHS + DS exhibited superior biomechanical stability compared to CCS, DHS, and PFNA, thereby offering a more conducive environment for fracture healing. Additionally, it appeared that FNS represented a promising treatment strategy, warranting further validation in future studies.

In vitro biomechanical analysis of a locking self-compression screw model applied to Pauwels III and comminuted femoral neck fractures

Femoral neck fractures (FNFs) affect the young adult population and are intimately related to high-energy trauma. Despite innovations in osteosynthesis materials, the rate of complications remains at 10%–59% in Pauwels type III (PIII) fractures. The authors thus propose a fixation model with a novel self-compression screw, comparing it to a sliding hip screw plate associated with a derotation screw in the fixation of a PIII fracture with posterior inferior comminution. The finite element method (FEM) was used in this comparison along with a virtual femur model with structural characteristics similar to those of a healthy young human bone. We formed 4 groups: Group 1 (GC), intact bone; Group 2 (SHS+S), sliding hip screw plate with derotation screw; Group 3 (XS), X-pin + SS (self-compression model with superior positioning screw); Group 4 (XI), X-pin + IS (self-compression model with inferior positioning screw). A 700 N monotonic load was applied to the apex of the femur head towards the ground so that stress was mainly focused on the fracture site and osteosynthesis. Analyses included total displacement and maximum principal stress and were performed for all groups. Fracture displacement, rotation, and von Mises were assessed only in groups that underwent osteosynthesis. Total displacement values in groups with self-compression screws (XS and XI) were closer to those for healthy femurs, with a 38.5% reduction when comparing the XS group with the SHS+S group. Fracture displacement and rotation values presented reductions of over 60% when comparing the XS and XI groups with the SHS+S group. Equivalent Von Mises stress values were similar between XS and XI and presented a reduction of approximately 5.25% when compared with the SHS+S group. Our FEM analyses demonstrated that the self-compression screw model has potential biomechanical advantages over the SHS+S model.

Medial Locking Plate Can Increase the Fixation Stability of Vertical Femoral Neck Fracture in Young Adults?

Introduction: Vertical femoral neck fractures in young adults are usually caused by high-energy trauma. These injuries are difficult to stabilize due to significant shear forces acting on the fracture site. Their treatment is challenging and with high risks of complications, such as fixation failure, malunion, nonunion, and avascular necrosis of the femoral head. Material and Methods: It compared the biomechanical stability provided by 3 different fixation methods: (1) dynamic hip screw with derotation screw, (2) cannulated screws with a conventional medial bone plate, and (3) cannulated screws with a locked medial bone plate. These fixation structures were applied on fourth-generation medium-sized synthetic bones, with a 17 pound per cubic foot cellular foam core and cervico-diaphyseal angle of 120 degrees were used. The comparison was performed through biomechanical tests under cyclic loading followed by an ultimate load. The interfragmentary movement at the fracture site was the main variable for the cyclical phase. Results: The biomechanical comparison showed no statistical differences (P > 0.05) in stiffness, micromovement level, and mechanical resistance among the fixation techniques evaluated. Discussion: To stabilize the vertical femoral neck fracture in young patients, the use of a medial bone plate associated with cannulated screws on a “tie-rod” assembly is an option that supports the mechanical demand until the fracture healing. The locked medial plate did not provide an advantage compared with the conventional bone plate.

To Evaluate Functional Outcomes of Dynamic Hip Screw with Derotation Screw versus Cannulated Cancellous Screw in Basicervical Fracture Neck of Femur in Adults

To Evaluate Functional Outcomes of Dynamic Hip Screw with Derotation Screw versus Cannulated Cancellous Screw in Basicervical Fracture Neck of Femur in Adults

A COMPARATIVE STUDY OF USING DYNAMIC HIP SCREW VS MULTIPLE CANCELLOUS SCREW FIXATION IN FRACTURE NECK OF FEMUR IN YOUNGADULTS

Introduction: Incidence of fracture of neck of femur is increasing in young adults. Dynamic Hip Screw with a derotation screw or CC screw is used in operation to reduce and stabilize femoral neck fractures. the commonest complications of intracapsular fractures of neck femur are non-union and avascular necrosis. Material And Methods: The study included 40 patients with history of trauma and diagnosed with fracture neck of femur. After thorough evaluation of patient , Pre-operative radiograph of pelvis with both hips were taken. Routine preoperative profile was done in each patient, along with pre-anesthetic check-up. Follow-up X-rays were taken at each follow-up, which were scheduled at 6 weeks, 3 months, 6 months and at 12 months. Functional and radiological outcome were assessed by scoring Modified Harris Hip Score Observation And Results At 12 months: The mean Harris Hip Score in Group 1 was 84.69 ± 4.51 and in Group 2 it was 90.68 ± 2.54. The mean Harris Hip score at 12 months was significantly higher in Group 2 as compared to Group 1 (P=0.001). Conclusion: When it came to treating fractures of the neck of the femur in young adults, our research found that dynamic hip screw fixation performed better than cancellous screw fixation. In terms of functional outcome, the dynamic hip screw had a higher Harris Hip Score and a lower rate of avascular necrosis. Based on the findings of this study, we recommend using a dynamic hip screw rather than a cancellous screw to fix a fracture of the neck of the femur. We recommend larger studies because there is a lack of research comparing these two fixation modalities.

Finite element comparative analysis of three different internal fixation methods in the treatment of Pauwels type III femoral neck fractures

BackgroundComparison of 4 cannulated lag screws (3 inverted triangular cannulated screws + anti-rotating screws;4 CLS), dynamic hip screws + derotational screws (DHS + DS), and femoral neck fixation system (FNS) in the treatment of Biomechanical properties of middle-aged Pauwels type III femoral neck fractures.MethodsThe femur CT data of a healthy young volunteer was selected and imported into Mimics software to construct a three-dimensional model of a normal femur. Pauwels type III femoral neck fractures were simulated according to the 70° fracture line. Use Geomagic and SolidWorks software to optimize and build CLS, DHS + DS, and FNS fracture internal fixation models. Finally, Ansys software was used to analyze the stress distribution, peak value, and maximum displacement of the proximal fracture fragment and internal fixation; the displacement distribution, and peak value of the fracture surface at the fracture end.Results① The stress peaks of the proximal fracture fragments in the three groups were concentrated near the femoral calcar. The peak stress of the FNS group was the largest, and the DHS + DS group was the smallest. ②The displacement of the fracture fragments was all located at the top of the femur. The peak displacement of the FNS group was the largest, and the DHS + DS group was the smallest. ③ The internal fixation stress of the three groups is concentrated in the middle part of the device. The stress distribution of the first two groups of models is more uniform than that of FNS. The peak stress of FNS is the largest and the CLS is the smallest. ④ The internal fixed displacements are all located at the top of the model. The peak displacement of the CLS is the largest, and the DHS + DS is the smallest. ⑤ The displacement of the fracture surface is in the upper part of the fractured end. The peak displacement of the FNS group was the largest, and the DHS + DS group was the smallest.ConclusionCompared with the other two internal fixation methods, dynamic hip screw + derotational screw (DHS + DS) showed good biomechanical stability. When Pauwels type III femoral neck fracture occurs in young adults, DHS + DS can be given priority as the preferred treatment for this type of fracture.

Fixation stability scoring in inter-trochanteric femur fractures treated with osteosynthesis: A retrospective observational study

To find out the validity of a newly proposed fixation stability scoring system in IT fractures treated with osteosynthesis and its limitations if any.: Retrospective analysis of hospital records of patients with various types of intertrochanteric fractures treated surgically at Sri Siddhartha medical college, Tumkur from January 2021 till August 2022. The exclusion criteria were non-ambulatory patients prior to fall, non surgically treated patients, patients loosing follow up or patients who are not alive at the time of study. The scoring was done by three different observers for each patient’s immediate post operative x-ray, repeated at 1 month interval. Radiographs at the final follow up were assessed for fracture union or fixation failure. Parameters of the scoring system: 1) cortical buttress in AP view radiograph, 2) cortical buttress in lateral view radiograph, 3) Tip apex distance (TAD) of principle lag screw, 4) Entry point (in case of IM nail), 5) Location of tip of principle screw in the desired Cleveland zone. 6) Placement of Richard screw in the inferior half of neck (in case of DHS), 7) Use of additional derotation screw (DRS) (in case of DHS). Scores of all the observers showed statistically significant correlation with fixation failure rates. Results were good with the score of 7.5 and above, fair with 6.5 and above and poor when the score was below 6.5. The minimum acceptable score was 6.5 for extra-medullary devices and 7 for intra-medullary devices.: The newly proposed scoring system appears to be valid and promising intra operative guide for fixation of intertrochanteric fractures with a few limitations. Large scale multi centre prospective studies are needed in the future to support the current study or to further simplify this scoring system.

Novel slide compression anatomic plates of the femoral neck for treating unstable femoral neck fracture: A biomechanical study.

To compare the biomechanical stability of slide compression anatomic plates of the femoral neck, cannulated compression screws and dynamic hip screws with derotation screws for stabilizing unstable femoral neck fractures (Pauwels angle = 70°).Pauwels III femoral neck fractures were created on 45 Sawbones femurs and randomly assigned to three implant groups (1:1:1). The biomechanical stability of all Sawbones in each treatment group was evaluated with three tests. First, in the static loading test, the load-displacement curve, vertical stiffness (load/vertical displacement [N/mm]) and 5 mm failure load were recorded. Second, in the incremental cyclic loading test (700, 1000, and 1400 N), the cyclic-displacement curve and the displacement of the fragments were recorded. Third, in the torsion test, the torsional rigidity, maximum torque, and torsional angle corresponding to the maximum torque were recorded.The static compression test showed that slide compression anatomic place-femoral neck (SCAP-FN) had the largest vertical stiffness (275 ± 11 N/mm, p < 0.01) and 5 mm failure load (1232 ± 156, p < 0.01). The cyclic loading test showed that SCAP-FN had the lowest change in displacement after 30000 cycles of loading. The torsional stiffness and the maximum torque followed the order SCAP-FN > dynamic hip screw systems (DHS) + derotational screw (DS) > CCS, and the torsional angle corresponding to the maximum torque followed the order SCAP-FN < DHS + DS < CCS.The SCAP-FN construct provides stiffness and stability compared with other standard fixation techniques (3CS and DHS + DS). The fixation strategy of SCAP-FN might be sufficient for clinical use, indicating studies in the human body are warranted.

COMPARISON OF OUTCOME OF DYNAMIC HIP SCREW + DEROTATION SCREW VERSUS CANNULATED CANCELLOUS SCREWS IN FRACTURE FEMUR NECK

Introduction: Management of fracture of femur neck remains a challenge. Avascular necrosis of the femur head and nonunion of fracture are well- known consequences of neck of femur fractures. A union can be promoted by accurate reduction, rigid xation and compression. In our study, we are comparing the functional outcome of DHS+ derotation screw with CC Screws alone. Compare in terms of benets and complications. Thus, provide evidence for the treatment of neck femur fracture. To compare the functional outcome of neck femur fracture treated with DHS withAim: derotation screw or CC Screws alone. This study was conducted in the Department of Orthopaedics, SMS Hospital,Materials and methods: Jaipur over 20 months from June 2020 to December 2020. A total of 60 patients (30 in each group) of age 18-60 years, presenting with # Neck of the femur in orthopaedics wards were enrolled in this study. We found among 30 cases in the DHS group 29 united and the CCS group 26 ofResults: them united. The mean union time for the DHS group was 13 weeks as it was longer for the CCS group at 16 weeks. Also based on Harris Hip Score DHS with derotation screw has better outcome than CC Screws alone. DHS plus derotation screw is better than CCS alone forConclusions: fracture neck of femur, because of ease of `usage, functional outcome of patients and minimalization of complications

Femoral Neck Fracture Treated with Dynamic Hip Screw System with De-rotation Screw Versus Cannulated Hip Screws

Background: Fracture neck of femur has always presented a great challenge to orthopedic surgeons due to its nature of going into non-union and osteonecrosis of femoral head even with the best fixation method and adequate reduction. Treatment of fracture neck of femur varies according to patient’s age and fracture pattern. Purpose of this study was to compare the outcome of DHS with side plate and de-rotation screw with multiple cannulated hip screws in fracture neck of femur in adult.&#x0D; Materials and methods: This quasi-experimental study was carried out in the Department of Orthopedic Surgery, Chittagong Medical College Hospital from July 2017 to June 2019. Sixty patients age limit between 18 to 55 years, with (AO/OTA 31-B) fracture was taken by purposive sampling technique as per set criteria and were treated either by DHS with side plate and de-rotation screw or by cannulated hip screws. Harris Hip Score was used for evaluation of functional outcome of surgery. &#x0D; Results: In this study, out of 60 patients, male (83%) were more than female (17%), maximum age incidence was found in 26-36 years age group (30%), left side involvement was 51.7% and right side was 48.3%. Over 60% incidence was due to RTA. Functional outcome was 68% excellent and 24% good in DHS with de-rotation screw group and 55.6% good and 25.9% excellent in cannulated hip screw group according to Harris Hip Score. Only 6.7% had soft tissue infection, 13.3% had deep seated infection and delayed union, 10% had non-union and hip stiffness and 6.7% had AVN in DHS with de- rotation screw group and 10% had soft tissue infection, 6.7% had deep seated infection and delayed union, 13.33% had non-union and hip stiffness and 10% had AVN in cannulated hip screw group. Mean ± SD radiological union time in DHS with de-rotation screw group was 12.5 ± 1.225 weeks and in cannulated hip screw group was 13.61 ± 1.559 weeks.&#x0D; Conclusion: The functional outcome of fixation by DHS with de-rotation screw was better than fixation by cannulated hip screw for femoral neck fracture in adults.&#x0D; JCMCTA 2022 ; 33 (1) : 112-117

TO EVALUATE RADIOLOGICAL AND FUNCTIONAL OUTCOMES OF INTRAMEDULLARY OSTEOSYNTHESIS OF SUBTROCHANTERIC FEMUR FRACTURES IN ADULTS WITH LONG PROXIMAL FEMORAL NAIL

Background: The subtrochanteric fractures accounts for 10-34% of hip fractures. Operative treatment is gold standard in adults in view of anatomical location, deforming forces &amp; vascularity issues. Intramedullary device are less invasive, more biological &amp; mechanically stable whereras extramedullary methods achieves better anatomical reduction but at the expense of vascularity. However, there is still no consensus over the methodology for being the best for these fractures. Objective: To evaluate clinical, functional and radiological outcomes of intramedullary osteosynthesis of subtrochanteric femur fractures in adults with long PFN. Methods: A prospective randomized control study was conducted on total 30 patients of subtrochanteric fractures and treated with long proximal femoral nail (PFN). All the patients were followed up for a maximum of 24 weeks. Outcomes were observed &amp; analysed such as tip apex distance, duration of surgery, complications, functional and radiological outcomes. Results: The average age of patients was 43.6 years ±13.26. Left sided fracture were more than right sided fracture. The most common type of fracture as per AO-ASIF classication was 32-C3 (53.33%). In 21 patients compression screw used was 95mm or above. Derotation screw of size 85mm or above were inserted in 19 patients. Mean TAD of compression screw and derotation screw was 11.59 and 13.81 respectively. Closed reductions was achieved in 27 patients. Mean surgical time was 157 minutes. Mean radiological union time of fracture was 14.16 weeks. Mean Harris hip score at 24 weeks was 84.56. Conclusions: It is concluded that intramedullary xation by long PFN is a sound and effective modality for the subtrochanteric fractures. Subchondral xation of both proximal screws probably has led to better stable xation with hundred percent union rates and no implant failure.

Medial Locking Plate Can Increase the Fixation Stability of Vertical Femoral Neck Fracture in Young Adults?

Vertical femoral neck fractures in young adults are usually caused by a high-energy trauma. These injuries are difficult to stabilize due to significant shear forces acting on the fracture site. Their treatment is challenging and has a high risk of complications, such as fixation failure, malunion, nonunion and avascular necrosis of the femoral head. In recent years, several studies have focused on the use of direct reduction of vertical femoral neck fractures in young adult patients. This technique allows for anatomical reduction as well as the placement of an intra-articular implant to avoid shear forces at the fracture site. The aim of this study was to evaluate, based on in vitro experimental tests, the biomechanical stability provided by three different fixation methods: (i) dynamic hip screw with derotation screw, (ii) cannulated screws with a conventional medial bone plate and (iii) cannulated screws with a locked medial bone plate. For the biomechanical tests, these techniques were applied to reduce the vertical osteotomy performed on synthetic bones for later verification of the mechanical behavior under axial cyclic loading and destructive axial loading. There were no statistical differences in stiffness, micromovement displacement and mechanical strength during the biomechanical comparison of the fixation methods. Therefore, we conclude that the use of a conventional medial bone plate associated with cannulated screws, with a transverse trochanteric screw, supports the mechanical demand while the fracture is healing and this option can be used to stabilize vertical femoral neck fractures in young patients.

Provisional fixation of unstable femoral neck basicervical fractures: A web-based survey and biomechanical assessment using a sliding hip screw construct

Objectives:Many hip fractures are considered rotationally unstable, especially during lag screw insertion. To counteract this instability, multiple provisional fixation constructs have been used to maintain the fracture reduction. This study aimed to compare the methods of provisional fixation biomechanically in ba sicervical femoral neck fractures.Methods:A web-based survey was sent by e-mail to members of three orthopedic assocations with questions concerning used techniques for provisional fixation of unstable basicervical femoral neck fractures and these results were used to guide our biomechanical assessment. Twenty, fourth-generation composite proximal femurs were osteotomized in the basicervical region to simulate a basicervical fracture. These fractures were anatomically reduced and one of the four provisional fixation constructs was applied. A sliding hip screw was then inserted with a torque limiter to the appropriate depth. The amount of fracture displacement during screw insertion was collected and analyzed.Results:Of the 142 respondents, 79.6% apply some form of provisional fixation. Derotational screw was the most commonly used provisional fixation (43.4%), followed by one superior Kirschner wire (K-wire) (39.8%). Biomechanically, the single derotation screw construct showed significantly less displacement (0.92 mm) than the one superior K-wire construct (3.09 mm). No other significant differences in fracture displacement were found between the groups.Conclusion:This study highlights that the majority of surgeons apply a form of provisional fixation during the surgical management of unstable basicervical femoral neck fractures. We have shown biomechanically that the single derotation screw had superior rotational stability when compared to the one superior K-wire.

Comparative Study of the Management of Intertrochanteric Fracture Femur With Proximal Femoral Nail vs. the Dynamic Hipscrew With Derotation Screw in Elderly Population.

Background: Intertrochanteric fractures can be treated, both by conservative and operative methods depending upon the status of the patient. The purpose of this study was to assess the functional outcome of intertrochanteric fracture of femur treated with dynamic hip screw (DHS) with de-rotation screw comparing and proximal femoral nail (PFN).Methodology: We compared 30 (male: 23, female: seven) cases of intertrochanteric fractures with a mean age of the population was 65 years and male to female ratio in was 2.75:1. Patients were recruited in this study having inclusion criteria of adults above 50 years of age, isolated intertrochanteric fractures of the AO Foundation/Orthopaedic Trauma Association (AO/OTA) type A1 and A2, fracture less than two weeks, and intertrochanteric fracture with or without distal extension.Results: Post-operatively, patients treated by either of these two methods were statistically analyzed in terms of comparing advantages and disadvantages in terms of the time of fracture union and outcome of both above-mentioned procedures using Harris hip score.Conclusion: PFN gives better results than DHS with De-Rotation Screw-in intertrochanteric fractures in terms of the amount of blood loss during surgery, duration of surgery, early toe-touch weight-bearing, and Harris hip scores. There is no difference between the two modalities in terms of duration of hospitalization, fracture union, mortality and morbidity, and postoperative complications.

Modified F configuration in the treatment of Pauwels type III femoral neck fracture: a finite element analysis

BackgroundThe optimal treatment of Pauwels type III femoral neck fracture (FNF) in young patients remains a worldwide challenge in orthopedic surgery.MethodsFinite element models of four internal fixations were developed to treat Pauwels type III FNF: a: the traditional inverted triangular parallel cannulated screw (PCS) model, b: the F-technique cannulated screw model, c: the modified F-technique cannulated screw model using a fully threaded screw instead of a partially threaded distally, d: the dynamic hip screw coupled with derotational screw (DHS + DS) model. Under the same conditions, finite element analyses were carried out to compare the displacement and von Mises stress distribution of four internal fixations and femurs, the maximum crack distances of the fracture surfaces, Z axis displacements of four models as well as the stress distribution in the subtrochanteric region.ResultsThe modified F-technique configuration resulted in a more stable fixation as compared to the other three configurations, with respect to the maximum displacement and stress peaks of femur and internal fixations, the maximum crack distances of the fracture surfaces, Z axis displacements of four configurations as well as the stress distribution in the subtrochanteric region.ConclusionsOur results suggested that modified F-technique configuration show a better performance in resisting shearing and rotational forces in treating Pauwels type III FNF compared to those using traditional inverted triangular PCS, the F-technique configuration or DHS + DS, providing a new choice for the treatment of FNFs.

Static and dynamic examination of a locking plate in various setups for the stabilization of bone shaft fractures, including periprosthetic

Introduction: Hip and knee arthroplasty, formerly known as the “gold standard” in the treatment of articular cartilage damage, after a period of being highly popular, are changing the way they are perceived over time due to their related complications. The number of complications is directly proportional to the number of prostheses placed. This is the case of numerus arthroplasty surgeries, also involving other joints. Since there is no tissue compatibility between the metal prosthesis and the bone tissue, the former represents a negative biological element that hinders the healing of the fracture. Objective of the study: The study aims at addressing the following questions: 1. What is the elasticity of the fixation with a locking plate depending on the number of screws in both fragments, in the case of interfractural diastasis?, 2. What is the elasticity of the fixation with a locking plate depending on the number of screws in both fragments, in the case of fracture-on-fracture compression? 3. What is the difference in elasticity of the fixation using the cable system on a fracture with prosthesis?, 4. Determining the influence of different stabilization setups with the locking plate screws on the spacing of the fracture on the static and dynamic experimental model, 5. Is it possible to achieve elasticity of the stabilization stimulating bone union in a plate-based fixation, and when? Material and methods: The study was performed in the research laboratory of ChM. The subject of the study was the ChM 5.0 ChLP straight narrow compression locking plate with limited contact L-238, holes-15. The plate was mounted using ChM 3.5 locking screws: 5.0 ChLP 3.5 x 18T self-tapping screw and 5.0 ChLP 3.5 x 36T self-tapping screw. The test was carried out under static and dynamic conditions. Results and Conclusions: 1. The elasticity of the fixation with a locking plate at the interfractural diastasis is inversely proportional to the number of screws (plate deflection), 2. The elasticity of the fixation with a locking plate at the fracture-on-fracture compression is inversely proportional to the number of screws (fracture-on-fracture compression), 3. Application of the “cable system” on the fracture with prosthesis and the derotation screw optimizes the elasticity of the fixation and seems to be an optimal solution (in periprosthetic fractures), 4. Studies on the experimental static and dynamic model demonstrated that placing screws in all the openings of the plate is a restrained/clinically useless fixation. 5. The elasticity of the stabilization stimulating bone union can be obtained in the plate fixation supported by the "cable system".

Management of intertrochanteric fractures by dynamic hip screw VS proximal femoral nail

Introduction: Inter trochanteric fractures are more common in the age group of 20 years to 60 years due to high velocity road traffic accidents, Whereas inter trochanteric fractures may also be seen in elderly people due to mild to moderate severity of trauma in addition to high velocity trauma. The management of stable intertrochanteric fractures in young and old individuals either by Dynamic Hip Screw (DHS) or by Proximal Femoral Nail (PFN) and management of unstable IT fractures by PFN in both the age groups young and old. Materials and Methods: The study is conducted in the department of orthopaedics at Shadan Institute of Medical Sciences (SIMS). A total no. of 43 patients are included in the study out of which 20 are stable fractures, remaining are unstable fractures. The mean age is 34 years (range 20-60 yrs). The mean follow up period is 34 months (12-36 months). Results: Out of 20 patients with stable fractures treated by DHS, 15 pts (%) are excellent outcome, 3pts (%) good, 2 pts (%) fair, poor result is nil. Out of 23 patients with unstable IT fractures treated by PFN, 18 pts (%) are excellent, 3 pts (%) good, 1 pt (%) fair & 1 pt (%) with poor result. Conclusion: All IT fractures which are stable in young and old patients can be treated either by DHS or PFN with satisfactory outcome and all unstable fractures in young and elderly people should be treated by PFN. Irrespective of type of fracture, fixed by PFN has got the advantage of early mobilisation and weight bearing. Keywords: Proximal Femoral Nail, Dynamic Hip Screw, Intertrochanteric fractures, Osteoporosis, Derotation screw.

A Study on Management of Basicervical Neck Femur Fractures with Dynamic Hip Screw (DHS) and Derotation Screw Fixation

A Study on Management of Basicervical Neck Femur Fractures with Dynamic Hip Screw (DHS) and Derotation Screw Fixation

Results of proximal femoral nail in intertrochanteric fracture of femur

Introduction: Intertrochanteric Femur fractures comprise approximately half of all hip fracture caused by low energy mechanism. These hip fractures occur in characteristic population with risk factors including increasing age, female gender, osteoporosis, a history of fall and gait abnormality. In spite of great advances made in the field of trauma in last 50 years management of this fracture has always remained subject of debate. There are several internal fixation options for managing these fractures that generally fall into two categories: some form of intramedullary fixation or some form of plating. Proximal Femoral Nailing is load bearing device with rotational stability and also short lever arm in addition to indirect fracture reduction. Materials & Methods: In this age group, we have done a prospective study in 70 patients of proximal femur fractures of femur operated with proximal femoral nailing at our institute with follow up of 5 – 24 months. All patients between above 31 years of age with proximal femur fractures of femur admitted in tertiary center in government setup - meeting the inclusion and the exclusion criteria during the study period were the subjects for the study. Patient were regularly followed up radiologically. Final outcome is measured with Harris Hip Score. Results: In the present study, 70 cases of intertrochanteric fractures treated operatively with proximal femoral nail (PFN), and the results were analyzed. In this series, low velocity injury (Domestic fall) was the cause of fracture in the majority (70%), especially in the elderly female patients. Boyd & Griffin type 2 was the commonest type (42%) following fall while walking, etc. The operations were completed within 2 hours in 98% of the patients. For PFN minimum duration was 40 minutes and maximum duration was 150 minutes and mean duration was 80 minutes. On final follow up one patient had iatrogenic basicervical fracture, one patient had outward migration of screw, two patient had backout of derotation screw, 10 patient had varus collapse, five patient had abductor weakness on followup. On 6 month follow up thirty patient had separated lesser trochanter with union of fracture but there was no limitation of movement & any residual deformity. The functional result according to Harris Hip Score was found to be excellent in 51.42%, good in 31.42%, fair in 10% and poor in 7.14% of patients. Conclusion: Intertrochanteric fractures commonly occur in elderly persons, usually following minor trauma whereas in young patients a major trauma is needed to cause this fracture. Proximal femoral nail offer less invasive option for fixation of intertrochanteric hip fractures. Unstable fractures can be fixed faster and with lesser soft tissue dissection. On basis of our study we have concluded that PFN should always be considered for management of intertrochanteric fractures in young as well as elderly patients who have multiple pre-existing illness.

Medial Plating of Pauwels Type III Femoral Neck Fractures Decreases Shear and Angular Displacement Compared with a Derotational Screw.

The purpose of this mechanical study was to compare 2 methods of augmented stabilization of Pauwels type III femoral neck fractures. Ten matched pairs of young cadaveric femurs were cut 22 cm distal to the lesser trochanter. All specimens received a 70-degree osteotomy, which was stabilized with a 135-degree sliding hip screw. One of each pair received augmented fixation with a 6.5 mm fully threaded cannulated screw. The other specimen in the matched pair had additional fixation with a 3.5 mm 5-hole tubular plate placed at the inferior-medial femoral neck. Each specimen was tested under cyclic axial loading conditions (5000 cycles between 200 and 1400 N at 2 cycles/sec) and subsequently loaded to failure. The angular displacement (varus), interfragmentary (shear) displacement, and failure loads were calculated. In the augmented plate group, 7 specimens failed by angular displacement and 3 failed by shear displacement. In the augmented screw group, 8 specimens failed by angular displacement and 2 by shear displacement. The plate group was found to have significantly less angular displacement, regardless of completed cycles, than the augmented screw group (0.75 ± 0.35 degrees vs. 2.15 ± 1.99 degrees averaged across completed cycles, P < 0.01). Similarly, the plate group was found to have significantly less shear displacement, regardless of completed cycles, than the augmented screw group (0.77 ± 0.70 mm vs. 1.22 ± 0.92 mm averaged across completed cycles, P = 0.01). The average failure load of the plate group (4930 ± 1578 N) was also larger but not significantly different from the screw group (3824 ± 2140 N), P = 0.12. Augmenting sliding hip screw stabilization of a Pauwels type III fracture with a medial plate applied to the femoral neck significantly decreases angular displacement and shear displacement compared with augmentation with a derotational screw.