A rare occurrence of enchondroma with pathological fracture of proximal femur in an adult female: A case report

Background: Subtrochanteric femoral fractures are challenging for surgeons, as it has strong collapsing forces at fracture site.The management of sub-trochanteric fractures, especially nonunion is challenging.Proximal Femoral Nail can be helpful in achieving high success rate. But there was a lack of local evidence.
 Objective: To determine the Outcome of Subtrochanteric Femur Fractures Treated by Proximal Femoral Nail in a Tertiary Care Hospital.
 Material and methods: This prospective study was conducted from 1stJuly 2017 to 30th June 2019. The inclusion criteria were all the patients of both genders above 16 years of age presented to emergency department with subtrochanteric fractures of the femur. Exclusion criteria included pathological fractures, fractures in children, old neglected fractures and multiple fractures. Radiographs were taken and all the patients were classified according to Seinshemers classification. All the patients underwent internal fixation with Proximal Femoral Nail. The outcome of all patients were assessed by using Modified Harris Hip Score.
 Results: A total of 110 patients were included in the study. Mean age of patients was 30.05±8.59 years. 81 (73.63 %) patients were males and 29 (26.36%) were females. According to Seinshemers classification, we had 54 patients with Type II fracture, 35 patients with Type III fracture, 19 patients with Type IV fracture and 02 patients with Type V fracture. Mean duration of hospital stay was 06 days and mean time of full weight bearing was 12 weeks. In our study, excellent results were found in 71 patients (64.5%), good results in 28 patients (25.4%), fair results in 06 patients (5.4%) and poor results in 03 patients (2.7%).02 patients were lost in follow up. The mean Harris Hip score was 93.5± 5.42. 14 patients (12.7%) had minor complications including 06 patients with Superficial wound infections, 03 patients with Deep infection, 01 patient with Deep vein thrombosis and 04 patients had Fracture from distal tip of nail. All the fractures unite within 6 months period and no implant failure was observed.
 Conclusion: Proximal Femoral Nail is a good choice implant for the fixation of subtrochanteric femur fractures leading to high rate of union, fewer implant related complications and excellent functional outcome.
 Key words: Subtrochanteric, Femur fracture, Proximal Femoral Nail, Modified Harris Hip Score, Seinshemers classification, Complications

The study aim was to investigate bone mineral density (BMD) and body composition in old patients with amputated lower limbs.Materials and methods. This work is a cross-sectional study, which enrolled 31 patients, who underwent amputation of one of the lower extremities. The mean age of the study patients was 73.4±9.0 years, ranging from 60 to 101 years. The majority of study patients were men (77.4%). 41.4% of patients underwent amputation of the left lower limb, 58.6% – right. The time from amputation to enrollment in the study ranged from 4 to 444 months, with a median of 30 months. Bone mineral density in the lumbar spine and proximal femurs was analyzed by dual energy x-ray absorptiometry.Results. Osteoporosis in the proximal part of the left femur was registered in 51.7% of patients, osteopenia – in 17.2%, normal BMD – in 31.1% of cases. Osteoporosis in the proximal part of the right femur was observed in 64.0% of patients. In the lumbar spine, osteoporosis was found only in 6.9% of patients. The mean T-score in the lumbar spine reached +0.38 SD, in the proximal left femur – -1.5 SD, in the left femur neck – -2.1 SD, in the proximal right femur – -2.0 SD, in the right femur neck – -2.1 SD. In the case of amputation of the left lower limb, the left femur BMD averaged 710.8±239 mg/cm3, the left femur T-score – -2.6±1.6SD, the T-score in the left femur neck – –3.0±1.3 SD, with the intact left leg – 980.1±194 mg/cm3,–0.8±1.5SD,–1.5±1.2SD, respectively (p=0.002, p=0.005 and p=0.006). In case of amputation of the right lower limb, the right femur BMD reached 743.8±268 mg/cm3, right femur T-score – -2.4±1.7SD, the T-score in the right femur neck – -2.4±1.7SD, with the intact right leg – 909.9±211.0 mg/cm3, -1.2±1.5SD, -1.5±1.5SD, respectively (p=0.09, p=0.06 and p=0.1). The likelihood of developing osteoporosis in the left femur with amputation of the left leg increased by 9.8 times, compared with patients who had a preserved left lower limb (odds ratio=9.8; 95% CI=1.1–93.5; p=0.02). In patients with amputation of the left leg, inverse correlation was registered between bone mineral density and the time from the moment of amputation to inclusion in the study (r= -0.65, p=0.03).Conclusion. Preliminary results of this study demonstrate a decrease in bone mineral density in the proximal femur of the amputated limb. Further studies are needed to study BMD in amputees and to elucidate the pathogenetic basis of the relationship between BMD and other clinical and laboratory parameters in this group of patients.

Background: Subtrochanteric fractures are included among those injuries caused by severe high energy trauma in the younger population. However, in the older population, this particular hip injury is caused by trivial fall and osteoporotic bones in the elderly population. It is difficult to treat these kinds of fractures easily. In order to avoid major complication such as mortality, the early surgical treatment regime is required to be followed. Aim: To compare and study the clinical and radiological outcome of subtrochanteric fracture femur fixed by Dynamic Condylar Screw (DCS) and Long Proximal Femur Nail (PFN) Materials and Methods: Total of 30 patients was included in the study. Simple randomization technique was employed to categorized patients for either PFN treatment or DCS treatment. Fifteen patients out of 30 were treated using PFN, and the remaining 15 were treated using DCS using close reduction. The study period was from July 2017 to June 2019. All the patients with subtrochanteric femur fractures within two weeks of injury were included for the study. Patients’ follow-up was done at 6-weeks, 3-months, and 6 months. Results: The highest number of patients, i.e. 40%, was aged between 51 and 60 years with the mean age of 58.231.26 years. The number of male patients (66.66%) was higher as compared to female patients. The mode of treatment for 50% of patients was PFN while it was DCS for the remaining 50% of the patients. The highest number of patients, i.e., 50% had Type III femur fracture. The patients treated using PFN showed improved functional outcome as compared to the patients treated using DCS. The patients were able to bear full weight within five weeks of surgery. The mean union time for patients treated with PFN was 16 weeks, while the mean union time in patients treated with DCS was 19 weeks. Also, the mean Harris Hip Score for patients treated with PFN was 90 and for the patients treated with DCS was 85. Conclusion: In light of the above resul

<p class="abstract"><strong>Background:</strong> <span lang="EN-AU">Trochanteric fractures are the most common fractures encountered accounting for 50% of all hip fractures. Subtrochanteric femur fractures have high rate of complications associated with their management. 10%–34% of all hip fractures occur in the subtrochanteric region</span><span lang="EN-IN">.</span>The study was <span lang="EN-AU">to compare the </span><span lang="EN-IN">clinical outcome of trochanteric and subtrochanteric fracture femur with proximal femoral nail (PFN) versus dynamic hip screw (DHS).</span></p><p class="abstract"><strong>Methods:</strong> <span lang="EN-IN">A prospective study of 50 patients with intertrochanteric and subtrochanteric fracture among which 30 were treated with Proximal Femoral Nail and 20 with Dynamic Hip Screw at SSIMS-SPARSH Davangere, Karnataka, India between June 2015 to November 2016.</span><span lang="EN-AU"> At final follow up results were assessed with Modified Harris Hip score</span>.<strong></strong></p><p class="abstract"><strong>Results:</strong> <span lang="EN-IN">Among the PFN Intertrochanteric fracture group, 9 patients showed excellent outcome, 6 patients showed good outcome and 2 patients showed fair outcome and 1 patient showed poor outcome. Among the PFN subtrochanteric fracture group, 7 patients showed excellent outcome, 3 patients showed good outcome and 1 patients showed fair outcome and 1 patient showed poor outcome. Among the DHS intertrochanteric fracture group, 3 patients showed excellent outcome, 3 patients showed good outcome and 2 patients showed fair outcome and 2 patient showed poor outcome. Among the DHS subtrochanteric fracture group, 1 patients showed excellent outcome, 2 patients showed good outcome and 3 patients showed fair outcome and 4 patient showed poor outcome</span><span lang="EN-IN">. </span></p><p class="abstract"><strong>Conclusions:</strong> <span lang="EN-IN">Fractures of the trochanteric region of the femur need a proper selection of implant based on fracture pattern. DHS has excellent results when used on stable fractures. For unstable fractures, PFN is the implant of choice. In case of subtrochanteric fractures PFN has better results in both stable and unstable fractures compared to DHS with less failure rates and restoring better hip biomechanics</span><span lang="EN-IN">.</span></p>

Intramedullary implants, such as the proximal femur nails (PFN), are inserted for the treatment of per-, inter- and subtrochanteric fractures. The initial experiences with these PFN, carried out by AO/ASIF in 1996, have been published. This study makes a systematic examination of the complications and clinical treatment results from 133 patients treated at our clinic from December 1997-2001 with 139 PFN in per-, inter- and subtrochanteric femur fractures. The mean age at the time of surgery was 78.4 years. All fractures were classified according to the AO system. The most frequent injuries were 31 A2.3 fractures (61.2%). All intraoperative image-converter images and all radiographs from the total period of treatment were evaluated retrospectively in accordance with 28 criteria. The degree of osteoporosis was estimated using the Singh classification. A total of 44 (31.7%) complications arose in 31 (23.3%) patients. On 11 occasions, hip screw cut-out was observed. Of these, two cases involved a Z-effect and one an inverted Z-effect. Two patients suffered a femoral neck fracture following removal of the hip screws. There were 38 (27.3%) reoperations required with 13 changes in procedure. In autumn 2002, clinical follow-up examinations were carried out on 65 (48.9%) patients who were assessed according to the Merle d'Aubigné score. A total of 51 (38.3%) patients had died at the time of follow-up. Normal ambulation was achieved by 33.8% of patients, while 64.6% were free of pain. The PFN is an appropriate implant in cases of per-, inter- and subtrochanteric femur fractures. Anatomical resetting and correct implant positioning are the keys to successful osteosynthesis. The risk of implant failure is highest in the case of multi-fragmentary per- and intertrochanteric fractures in which medial strengthening has been degraded in patients aged over 80 years. The clinical results in elderly patients are unsatisfactory.

To compare the efficacy of percutaneous cementoplasty (PCP) with and without interventional internal fixation (IIF) on malignant impending pathological fracture of proximal femur. A total of 40 patients with malignant impending pathological fracture of proximal femur were selected for PCP and IIF (n = 19, group A) or PCP alone (n = 21, group B) in this non-randomized prospective study. Bone puncture needles were inserted into the proximal femur, followed by sequential installation of the modified trocar inner needles through the puncture needle sheath. Then, 15-45 ml cement was injected into the femur lesion. The overall excellent and good pain relief rate during follow-ups were significantly higher in group A than that in group B (89 vs. 57 %, P = 0.034). The average change of VAS, ODI, KPS, and EFES in group A were significantly higher than those in group B at 1-, 3-, 6-month, 1-year (P < 0.05). Meanwhile, The stability of the treated femur was significantly higher in group A than that in group B (P < 0.05). PCP and IIF were not only a safe and effective procedure, but resulted in greater pain relief, bone consolidation, and also reduced the risk of fracture than the currently recommended approach of PCP done on malignant proximal femoral tumor.

Introduction: The difficult nature of treating subtrochanteric fracture stems in part from the fact that this injury pattern is anatomically distinct from other proximal femoral peritrochanteric fractures and also from the femoral shaft fractures. The present study was made attempt to evaluate the functional outcome of subtrochanteric femur fractures treated with proximal femoral nail. Materials and Methods: The present study conducted on subtrochanteric femur fracture cases admitted in GSL medical college and general hospital, Rajahmundry during December 2013 to July 2015. Ethical Committee Clearance was obtained before beginning of the study. All patients were maintained on traction before surgery. All surgeries were done under spinal or epidural anaesthesia, low molecular weight heparin prophylaxis is given subcutaneously for the high risk patients during the hospitalization. Result: Majority of the cases were due to high energy trauma of Road traffic Accidents involving relatively younger patients. The operating time for 72% cases was between 1 to 2 hours. Operating time decreased with increasing familiarity of the implant system. The average length of Hospital stay was 17.6 days. At the end of five months, all except three patients could mobilise independently without any aid. According to harris hip score, 3 (12%) patients had excellent outcome, 18 (72%) patients had good outcome and 4 (16%) patients had fair outcome. Conclusion: In conclusion, Proximal femoral nail is a good implant for subtrochanteric fracture of the femur. The advantages are minimal exposure (closed technique), better stability and early mobilisation. Fractures united in all cases and postoperative functional outcome was satisfactory. Keywords: Subtrochanteric femur fractures, Proximal femoral nail, Harris hip score, Functional outcome.

The femur or thighbone is the longest and strongest bone, which bears the maximum weight of the human body. There are various types of fracture occurs in femur bone. The intertrochanteric and subtrochanteric fractures are very complex to treat and generally stabilized by proximal femoral nail. The aim of the present research work is to select the proper implant and its respective material during the fixation of intertrochanteric and subtrochanteric fractures of femur. Such type of study helps the orthopedic surgeons to predict the failure of implant. In the present study, the modeling software SolidWorks 17 is used to create the 3D model of the implant. The dimensions for 3D geometric model of implant are taken with the help of Vernier caliper. The FEM software ANSYS 16.2 is used for simulation. The finite element analysis is performed to study the distribution of stress and deformation under one-legged static load boundary conditions. The deformation and stress values on the proximal femur are compared between titanium and stainless steel implant material in case of both subtrochanteric and intertrochanteric fractures of the femur. The bone healing process mainly depends on the stability given to the fracture. The stability is achieved by checking the bone contact surface area at fracture interface surface. The frictional stress and contact pressure at fracture plane are compared by taking both titanium and stainless steel implant material. These contact results are used to estimate the condition of healing process at the fracture interface of intertrochanteric and subtrochanteric fractures. The effect of frictional stress, pressure developed and localized stress on bone healing is also discussed.

IntroductionSolitary plasmacytoma of the bone is a rare neoplasm characterized by proliferation of neoplastic plasma cells in the bone in the absence of systemic involvement. We present a managed case of a 64-year-old male with solitary bone plasmacytoma of the right proximal femur, who presented as a pathological subtrochanteric femur fracture.Case ReportA 64-year-old male presented to our outpatient department with pain in the right hip and restricted range of motion following a trivial trauma. The radiographs showed an osteolytic lesion in the right proximal femur with a right subtrochanteric femur fracture. A magnetic resonance imaging scan revealed a well-defined lesion in the right proximal femur. A 18F-fluorodeoxyglucose positron emission tomography did not show a lesion at any other site suggesting that the lesion was solitary. A serum protein electrophoresis study was normal and the urine was negative for myeloma protein. The patient had a score of 12 as per Mirel’s criteria and hence required operative intervention and fixation. The patient was managed with a thorough mechanical and chemical curettage of the lesion followed by fixation with a proximal femur locking plate and augmentation with fibula and iliac crest bone graft. He was then given a chemotherapy regimen consisting of nine cycles of bortezomib, lenalidomide, and dexamethasone.ConclusionSolitary bone plasmacytoma is a rare neoplasm of the bone. Early diagnosis and intervention are required to manage it and prevent its progression to multiple myeloma, which is a more aggressive entity and lies at the other end of the spectrum of plasma cell dyscrasias. Management of this lesion requires an active participation of the hematologist and a holistic approach which includes radiotherapy or surgery with possible adjuvant chemotherapy.

Objective: To assess the functional &amp; radiological outcomes of proximal femoral nailing (PFN) in treating subtrochanteric femur fractures in adults. Study Design: Prospective study. Setting: Afridi Medical centre &amp; Teaching Hospital Peshawar Pakistan. Period: Jan 2022 to October 2024. Methods: Patients of age 20 to 80 years admitted due to acute subtrochanteric (ST) femur fractures were included in the study. Open &amp; pathological ST fractures were excluded. The Harris Hip Score was utilised to assess the postoperative outcomes. In all the cases, patients were put on immobilization preoperatively followed by closed reduction &amp; fixation with PFN under spinal anaesthesia. Both radiological outcome by examining radiological union at fracture site and functional outcome through determining Harris Hip Score were determined at 4 months postoperatively. Microsoft excel was used for data analysis. Results: Radiological union was observed in the patients as early as 14 weeks postoperatively followed by radiological union in all the patients at 16th week postoperatively and no non-union case was observed in our study. Out of all 91 cases only 5 cases were having mild surgical site infection which was managed accordingly the sterile dressing and oral antibi.=otics. The overall Harris hip score to be 90.75±6.85 in our study. Among total 91 patients 68 (74.72%) patients fall in excellent, 15 (16.48%) in good, 6 (6.6%) in fair while 2 (2.2%) in poor categories of Harris hip score. Conclusion: PFN is an effective implant for treating femoral subtrochanteric fractures. The advantages include reduced surgical exposure, increased stability, and early mobilisation. Because it allows for early and stable mobilization, PFN may be superior for treating subtrochanteric fractures in the elderly as well.

INTRODUCTION: This study aims to compare the outcomes of the Musculoskeletal Tumor Society Score (MSTS) and complications between Intramedullary Nailing (IMN) and Bipolar Hemiarthroplasty (BHA) in patients with pathological fractures of the proximal femur due to Metastatic Bone Disease (MBD) at three months post-operation. MATERIALS &amp; METHODS: The study included 30 patients with MBD who experienced proximal femur fractures at RSUP Prof. Dr. I.G.N.G. Ngoerah Denpasar, Bali. A total of 16 patients underwent IMN, while 14 patients underwent BHA. Patient characteristics, MSTS scores, and complications such as implant failure and infection were analyzed using appropriate statistical tests. Data normality was tested with the Shapiro-Wilk test, and data homogeneity was tested with the Levene test. RESULT: The mean age of the patients was 57.93 ± 12.97 years, with the majority being female (86.7%). The MSTS score distribution at three months post-operation showed normal and homogeneous data distribution. The mean MSTS score of patients undergoing BHA was significantly higher than those undergoing IMN (24.28 ± 2.78 vs. 17.87 ± 2.41; MD 6.41; 95%CI 4.46-8.35; p &lt; 0.001). There were no significant differences in the proportions of implant failure (IMN 12.5% vs. BHA 7.1%; p=0.552; OR=1.86; 95%CI [0.15-22.9]) or infection (IMN 6.3% vs. BHA 14.3%; p=0.448; OR=0.4; 95%CI [0.03-4.9]) between the two groups. CONCLUSION: Bipolar Hemiarthroplasty resulted in significantly better MSTS scores compared to Intramedullary Nailing in patients with pathological fractures due to MBD at three months post-operation. However, there were no significant differences in complications such as implant failure and infection between the two surgical techniques. Keywords: Metastatic Bone Disease, proximal femur fractures, Intramedullary Nailing, Bipolar Hemiarthroplasty, MSTS score, complications

Background: Fractures of the proximal femur are a big challenge in traumatology. Rapid strides in implant and instrumentations in quest of ideal fixation of subtrochanteric femoral fractures have made various options available. Objective: The present study aims to study the role of standard proximal femoral nail (PFN) in the management of these fractures. This study aimed to evaluate the results of treatment of subtrochanteric femoral fractures using PFN. Patients and methods: This prospective study conducted at Orthopedic Department, Zagazig University Hospital, from November 2020 to July 2021. It included 24 patients, complaining of closed subtrochanteric fractures treated with PFN (Gamma intramedullary nail). The age ranged from 23 to 87 years (with mean54.21 years), 13 of them were males and 11 females. Road traffic accident (RTA) represented the most common mechanism of injury in 10 patients (41.7%) while fall down represented (37.5%) in 9 patients, and fall from height in 5 patients (20.8%). Results: there was statistically significant difference in HHS among patients with different age groups, mechanism of injury and presence of diabetes mellitus (DM) as associated condition. Statistically there was significant correlation between type of reduction and diabetes mellitus with Harris hip score. Conclusion: This study concluded that the Gamma nail is an excellent choice in treatment of subtrochanteric fractures as it has many advantages as allowing for early functional exercise and full weight-bearing of the affected limb, shortening the duration of operation, high rotation stability, small wounds and minimizing blood loss along with risk of infection

Background: Subtrochanteric femur accounts for 10–30% of peri-trochanteric fractures. They need early fixation to avoid complications of prolonged immobilization. Proximal femoral nail (PFN) and dynamic condylar screw (DCS) fixation are most commonly used for subtrochanteric fracture fixation. Aims and Objectives: The purpose of the study was to evaluate the outcomes of PFN and DCS fixation of the subtrochanteric fracture. Materials and Methods: This descriptive follow-up study was conducted in Bankura Sammilani Medical College, Department of Orthopedics from May 2020 to October 2021. A simple random sampling technique with an estimated sample size of 40 patients in PFN group and 40 patients in DCS group was taken. Results: Among the PFN cases, 24 (60%) cases were reduced by closed reduction, and 16 (40%) cases were reduced by open reduction. Among DCS cases, 30 (75%) were reduced by open reduction. The average operating time in PFN patients was 80 min and in DCS patients was 104 min. The average blood loss in PFN patients was 178 mL and for DCS patients 252 mL. The average union time of PFN cases was 15.56 weeks and DCS group was 18 weeks. Out of 40 cases of PFN, there were 24 excellent, 8 good, 6 fair, and 2 poor functional outcome by Harris hip Score, and DCS fixation had 6 excellent, 16 good, 12 fair, and 6 poor functional outcome. Conclusion: There are no major differences in union rate and complication rate between the PFN and DCS. Although PFN has advantages over DCS in terms of decreased blood loss, decreased operative time, faster union, and a greater chance to closed reduction. Overall, it gives better functional result than DCS.

The proximal femur is a common location for pathologic fractures in children, yet there is little published information regarding this injury. The purpose of this study was to investigate the outcomes of pediatric pathologic proximal femur fractures due to benign bone tumors. A retrospective review of patients treated for pathologic proximal femur fractures from 2004 to 2018 was conducted. Inclusion criteria were age below 18 years and pathologic proximal femur fracture secondary to a benign bone tumor. Patients were excluded if they had <1 year of follow-up. Medical charts and serial radiographs were reviewed for fracture classification, underlying pathology, treatment, complications, and time to fracture healing. A total of 14 patients were included. Mean age was 6±3 (3 to 11) years, and mean follow-up was 44±21 (22 to 86) months. Index treatment was spica casting in 9/14 (68%) patients, while 5/14 (32%) were treated with internal fixation. Of the 9 patients initially treated with casting, 22% (2/9) required repeat spica casting at a mean of 0.6 months after index treatment, 67% (6/9) required internal fixation at a mean of 20.3 months after index treatment, and 11% (1/9) did not require revision treatment. Eighty-eight percent (8/9) of patients treated with casting required revision treatment compared with 40% (2/5) of those treated with internal fixation (P=0.05). Nonunion occurred after 1 refracture, malunion with coxa vara occurred in 2 fractures, and the remaining 11/14 (84%) fractures had a union at a mean of 4.9±3.0 months All cases of malunion occurred in patients initially treated nonoperatively. There were 19 distinct complications in 10/14 (71%) patients. The incidence of any revision surgery was 64% (9/14). In this series, pediatric pathologic proximal femur fractures demonstrated prolonged time to union, high incidence of revision surgery (64%), and substantial complication rate (71%). In children with pathologic proximal femur fractures, treatment with internal fixation is recommended as this series showed a 78% failure rate of initial conservative management. Level IV.

The removal of three inverted triangular parallel cannulated screws after the femoral neck fracture healing is sometimes accompanied by osteonecrosis of the femoral head (ONFH) or its refracture. The purpose of this study was to determine the biomechanical changes of the femur before and after the screw removal using a finite element analysis. The CT data of the femurs were obtained from a 69-year-old healthy female to establish the femur models. The established finite element models consisted of N, C, and R groups: N group, the normal femur; C group (to simulate the femoral neck fracture healing after the internal fixation), the normal femur with three inverted triangular parallel cannulated screws (C1) or with two upper parallel screws (C2). For the R1 or R2 groups, the screws in the model of the C1 or C2 individuals were gradually removed in seven or three types of different screw combinations, respectively. The stresses and displacements of the femur were determined. (1) Compared with the N group, a uniform stress distribution was stopped by the addition of three screws in the C1 group; in contrast, all screw removals resulted in the stress concentration on the screw holes and the disappearance of stress shielding. Moreover, the average stress of the femoral head in C1 group increased by 37.85%, while that of the femoral neck decreased by 23.03%. (2) Compared with the C1 group, while only the lowest femoral calcar screw was removed, there was a similar stress distribution in the proximal femur, and the average stress of the femoral head increased only by 0.35% although that of the femoral neck increased by 63.62%; however, removal by any other means resulted in a significant stress concentration in the proximal femur and a significant increase in the average stresses of the femoral head and neck (5.96-40.95% and 12.82-75.46%, respectively). (3) Compared with the N or C1 group, there was a significant stress concentration on the screws and its surrounding proximal femur in the C2 group. (4) Compared with the C2 group, the simultaneous removal of two upper screws not only did not cause a significant stress concentration on the proximal femur but also significantly reduced the average stresses of the femoral head and neck by 87.49% and 65.51% respectively. On the contrary, the gradual removal of two screws caused a significant stress concentration on the screw and its surrounding proximal femur although the average stresses of the femoral head and neck decreased by 88.79-89.06% and 67.00-67.22%, respectively. (5) Compared with the N group, the average displacements of the femoral head and neck in the C1 group increased only by 3.12% and 3.37%, respectively. Additionally, compared with the C1 group, while three, two, or one screw was simultaneously removed, the average displacements of the femoral head and neck only fluctuated - 5.51-1.65% and 1.78-9.03%, respectively. Residual internal fixation after femoral neck fracture healing may lead to stress concentration on screws and stress shielding around screws. The first removal of the lowest femoral calcar screw and then the second removal of two upper residual screws have a minimum effect on the stress concentration on the proximal femur and the average stress on the femoral head. The incorrect screw removal and resulting femoral load may well be closely related to occurrence in ONFH or its refracture.