Nonunion of the humeral shaft successfully treated with teriparatide [rh (1-34) PTH]

We reported a case of atrophic nonunion after humeral shaft fracture in a patient with severe psychiatric disorders that advised against hospital admission and surgery. He was treated with teriparatide (recombinant human 1-34 parathyroid hormon) [rh (1-34) PTH] in daily subcutaneous injections. After 4 months of treatment, healing of nonunion, associated to clinical improvement and functional recovery of the patient, was observed. No other intervention was required, and no side effects attributable to the drug occurred.

Valgus osteotomy for nonunion and neglected neck of femur fractures

Nonunion neck of femur can be a difficult problem to treat, particularly in the young, and is associated with high complication rates of avascular necrosis due to the precarious blood supply and poor biomechanics.The various treatment options that have been described can be broadly divided according to the aim of improving either biology or biomechanics. Surgeries aimed at improving the biology, such as vascularized fibula grafting, have good success rates but require high levels of expertise and substantial resources. A popular surgical treatment aimed at improving the biomechanics-valgus intertrochanteric osteotomyoptimizes conditions for fracture healing by converting shear forces across the fracture site into compressive forces. Numerous variations of this surgical procedure have been developed and successfully applied in clinical practice. As a result, the proximal femoral orientation for obtaining a good functional outcome has evolved over the years, and the present concept of altering the proximal femoral anatomy as little as possible has arisen. This technical objective supports attaining union as well as a good functional outcome, since excessive valgus can lead to increased joint reaction forces. This review summarizes the historical and current literature on valgus intertrochanteric osteotomy treatment of nonunion neck of femur, with a focus on factors predictive of good functional outcome and potential pitfalls to be avoided as well as controversies surrounding this procedure.

Role of the Ilizarov non-free bone plasty in the management of long bone defects and nonunion: Problems solved and unsolved

BACKGROUND Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in long bone defect and nonunion management along with free vascularized grafting and induced membrane technique. However, the shortcomings and problems of these methods still remain the issues which restrict their overall use.AIM To study the recent available literature on the role of Ilizarov non-free bone plasty in long bone defect and nonunion management, its problems and the solutions to these problems in order to achieve better treatment outcomes.METHODS Three databases(Pub Med, Scopus, and Web of Science) were searched for literature sources on distraction osteogenesis, free vascularized grafting and induced membrane technique used in long bone defect and nonunion treatment within a five-year period(2015-2019). Full-text clinical articles in the English language were selected for analysis only if they contained treatment results,complications and described large patient samples(not less than ten cases for congenital, post-tumor resection cases or rare conditions, and more than 20 cases for the rest). Case reports were excluded.RESULTS Fifty full-text articles and reviews on distraction osteogenesis were chosen.Thirty-five clinical studies containing large series of patients treated with this method and problems with its outcome were analyzed. It was found that distraction osteogenesis techniques provide treatment for segmental bone defects and nonunion of the lower extremity in many clinical situations, especially in complex problems. The Ilizarov techniques treat the triad of problems simultaneously(bone loss, soft-tissue loss and infection). Management of tibial defects mostly utilizes the Ilizarov circular fixator. Monolateral fixators are preferable in the femur. The use of a ring fixator is recommended in patients with an infected tibial bone gap of more than 6 cm. High rates of successful treatment were reported by the authors that ranged from 77% to 100% and depended on the pathology and the type of Ilizarov technique used. Hybrid fixation and autogenous grafting are the most applicable solutions to avoid after-frame regenerate fracture or deformity and docking site nonunion.CONCLUSION The role of Ilizarov non-free bone plasty has not lost its significance in the treatment of segmental bone defects despite the shortcomings and treatment problems encountered.

Profunda femoris artery pseudoaneurysm following revision for femoral shaft fracture nonunion

Femoral artery pseudoaneurysms(FAPs) have been described following internal fixation of intertrocantheric, subtrocantheric and intracapsular femoral neck fractures as well as core decompression of the femoral head. The diagnosis of FAP is usually delayed because of non-specific clinical features like pain, haematoma,swelling, occasional fever and unexplained anaemia.Because of the insidious onset and of the possible delayed presentation of pseudoaneurysms, orthopaedic and trauma surgeons should be aware of this complication. We report a case of Profunda Femoris arterial branch pseudoaneurysm, diagnosed in a 40-year-old male 4 wk after revision with Kuntscher intramedullary nail of a femoral shaft nonunion. The diagnosis was achieved by computed tomography angiography and the lesion was effectively managed by endovascular repair. The specific literature and suggestions for treatment are discussed in the paper.

Outcome Assessment of Z-shaped Osteotomy in the Management of Humeral Shaft Nonunion Secondary to Failed Plate Osteosynthesis

Restoration of fracture alignment by osteotomy is crucial for the management of humeral nonunion. In the present study, we introduced a new way of osteotomy (Z-shaped) in treating humeral shaft nonunion secondary to failed plate osteosynthesis. Clinical data of 24 patients with humeral shaft nonunion following implant failure (from 2010 to 2014) were retrospectively evaluated. These patients underwent Z-shaped osteotomy in revision surgery after the initial surgery, plate osteosynthesis, was failed. Outcomes were evaluated using visual analogue scale (VAS) and Constant and Murley score. Repeated analysis of variance (ANOVA) was used for statistical analysis. Patients were followed up for a minimum of 24 months (26.83±4.33 months). The operative time was 102.33±10.16 min, and hospital stay averaged 9.75±2.13 days. All patients achieved clinical union at the latest follow-up. Complications included radial palsy (n=1) and superficial wound infection (n=1). The postoperative VAS scores decreased significantly compared to preoperative score (F=257.99, P<0.01). Constant and Murley score increased and reached 81.33±0.95 at 24 months' follow-up 0=247.35, P<0.01). Among all the cases, 15 cases were graded as "excellent", and 9 as "good". In conclusion, Z-shaped osteotomy was easy to perform, and it provided additional medial support with more bone contact areas. Revision surgery using locking plate and Z-shaped osteotomy achieved high union rate and improved functional outcome. It was a reasonable and safe option for treating humeral nonunion following implant failure.

Teriparatide as nonoperative treatment for femoral shaft atrophic nonunion: A case report

BACKGROUND Femoral shaft fractures are a common type of fracture among adults and have high union rates. However, clinical decisions are difficult to make because of the different types of nonunions. Atrophic nonunion usually requires revision surgery combined with bone grafting. Furthermore, no study of teriparatide administration for femoral atrophic nonunion have been previously reported. CASE SUMMARY A 60-year-old woman had a right femoral shaft fracture due to a traffic accident, and she immediately underwent closed reduction and internal fixation surgery with an intramedullary nailing. However, after 6 mo of rehabilitation, the fracture site showed no signs of healing, and her condition was diagnosed as atrophic nonunion. Subsequently, teriparatide was administered for 6 mo. Complete union was observed at the fracture site 6 mo after teriparatide discontinued. CONCLUSION The use of teriparatide can be a promising treatment to improve the healing of nonunion fractures.

Unusual presentation of congenital radioulnar synostosis with osteoporosis,fragility fracture and nonunion:A case report and review of literature

BACKGROUND Congenital radioulnar synostosis(CRUS)is a rare deformity of the upper extremity.It is characterized by loss of rotation of the involved forearm and functional limitations in daily activities.No studies on CRUS with osteoporosis have been reported to date,and osteoporosis is usually recognized as an important dimension of genetic disorder in children.We discuss the possible relationship among this disorder,osteoporosis and fracture nonunion,investigate the strict surgical indications and recommended treatments.CASE SUMMARY A 14-year-old male patient with bilateral CRUS with osteoporosis,fragility fracture and nonunion of fractures in ulna and radius presented our institution for further treatment,complaining of limitation in rotation.The bone mineral density of the hip and lumbar spine was 0.687 g/cm2 and 0.705 g/cm2,respectively,and the Z-score for both was-2.1,which revealed osteoporosis and a high risk of fracture.Tow serum bone turnover markers indicated an imbalance of bone metabolism.Reoperation for ulna fracture with autogenous bone grafting and a postoperative physiotherapy program were adopted rather than the separation of pathological synostosis.Radiological examination,observational posture assessment and limb function scale were evaluated before and 1 year after surgery.At 1 year,the fracture nonunion had almost recovered,forearm movement function on the fracture side was restored,and function on the healthy side was significantly improved compared with that before rehabilitation.CONCLUSION Surgical indications for CRUS vary from person to person.Surgery should not be the first choice of treatment,and physiotherapy is not inferior to surgical treatment.

Existing fixation modalities for Jones type fifth metatarsal fracture fixation pose high rates of complications and nonunion

Jones type fifth metatarsal fractures pose a challenge to the foot and ankle surgeon,given documented high nonunion rates as well as high complication rates including hardware prominence,nerve injury,and screw breakage for existing treatment modalities including screw and plantar plate fixation.We call for the design of innovative Jones-fracture specific implants which contour to the natural curve of the fifth metatarsal.Future research should aim to expand upon existing literature for Jones fracture fixation and evaluate efficacy of novel implants which are designed to address unacceptably high complication rates for existing treatment modalities.

Effect of Ilizarov external fixation combined with negative pressure sealing drainage and antibiotics in the treatment of infective tibial nonunion

Objective:Observation on the effect of Ilizarov external fixation combined with vacuum pressure sealing drainage and antibiotics in the treatment of infective tibial nonunion.Methods:79 patients with tibial infective nonunion who were treated in our hospital from August 2016 to August 2018 were divided into two groups according to random number table,with 39 patients in the control group treated with Ilizarov external fixation technology and 40 patients in the study group treated with vacuum pressure sealing drainage and antibiotics on the basis of the control group.Bone healing time and daily walking were recorded.Rasmussen score,serum intercellular adhesion molecule-1(ICAM-1)and IL-6 levels,lower limb Fugl-Meyer motor function score and lower limb BI index score were compared at different time.Results:The daily walking condition of the study group was significantly better than that of the control group(P<0.05),and the healing time of bone was significantly shorter than that of the control group(P<0.05);the Rasmussen score of the study group was higher than that of the control group at 1 month,6 months and 12 months after treatment(P<0.05);the levels of serum ICAM-1 and IL-6 in the two groups after treatment were lower than those before treatment(P<0.05),and the levels of serum ICAM-1 and IL-6 in the study group were lower than those in the control group after treatment(P<0.05).The lower limb Fugl-Meyer motor function score and lower limb BI index score of the two groups after treatment were higher than those before treatment(P<0.05),and the lower limb Fugl-Meyer motor function score and lower limb BI index score of the study group after treatment were higher than those of the control group(P<0.05).Conclusions:Ilizarov external fixation combined with vacuum pressure sealing drainage and antibiotics can promote the bone healing of patients with infective tibial nonunion,significantly improving their daily walking condition,alleviating inflammation,and recovering the knee joint function and lower limb function well.

Treatment for subtrochanteric fracture and subsequent nonunion in an adult patient with osteopetrosis:A case report and review of the literature

BACKGROUND As a congenital metabolic bone disease caused by defective osteoclastic resorption of immature bone,osteopetrosis is characterized by diffused sclerosis of bones,brittle bones,easy fracturing,narrow medullary canals,and a weak fracture healing ability.At present,clear standards and principles for the treatment of fractures in patients with osteopetrosis are lacking.Non-operative treatment can prevent fracture hematoma and preserve the blood supply to the bone fragments,while being associated with frequent failures and higher mortality rates.Meanwhile,closed reduction and internal fixation with intramedullary nail(CRIF+IMN)approaches can also protect blood supply to the fracture site.However,IMN cannot be used for the vast majority of patients with osteopetrosis due to the narrowing of medullary canals.Thus,open reduction and internal fixation with plate remains the most appropriate surgical method for treating fractures in patients with osteopetrosis,but this approach is complicated by the lack of intramedullary hematopoiesis in such patients.Fracture healing primarily depends on the blood supply to the external periosteum.Open reduction can also easily destroy the periosteum and cause delayed fracture healing or even nonunion;however,CRIF may be the most practical approach.As a result,it would be prudent to solve the difficulty of drilling during the operation and the problem of postoperative nonunion.CASE SUMMARY In 2018,we treated an adult patient with osteopetrosis presenting with a subtrochanteric fracture.The fracture was fixed using a femoral locking compression plate.Because of delayed consolidation,at 12 mo postoperatively the patient was further treated with platelet-rich plasma(PRP)combined with radial extracorporeal shock wave therapy(rESWT).Antero-posterior and lateral radiographs obtained at the latest follow-up(10 mo)showed that the callus had grown at the original fracture site,and the medial fracture line almost disappeared.CONCLUSION Osteosynthesis remains the first choice of treatment approach for fractures in patients with osteopetrosis,especially peritrochanteric fractures.Preoperative preparation is necessary to avoid risks such as drill bit breakage and iatrogenic fracture during the operation.Moreover,fractures in a patient with osteopetrosis present with a high risk of delayed union and nonunion,which can be potentially cured with PRP+rESWT.

Predictors of Nonunion in Humerus Shaft Fractures in Adults in Lomé(Togo)

Background: To identify predictors of humerus shaft fractures nonunion in adults whatever the type of treatment performed. Patients and Methods: We conducted a retrospective study among patients who had a fracture of the humeral shaft moving towards healing or nonunion. Patients were treated in the orthopedic trauma unit of Sylvanus Olympio Teaching Hospital and two other private clinics in Lomé between January 2008 and June 2012. On the X-ray of each patient, we measured the angulation, the diastasis, and inter fragmentary contact. For each included patient, we looked for: age, sex, medical history, body mass index (BMI), according to the third location of the shaft fracture, the type of fracture according to AO classification and the type of opening according Tscherne classification. Results: During the study period, 184 patients with humeral shaft fracture were identified. Of these 108 were men. The mean age of patients was 37.3 years. The fractures were treated conservatively in 100 patients (54.3%), 78 treated surgically and six (3.3%) have discharged from hospital against medical advice for traditional treatment. The factors that were associated with nonunion of humerus shaft fractures in these patients were: the opening of the fracture (RR = 4.5;95% CI = [2.9;7.1]), the presence of immediately radial paralysis (RR = 5.6;95% CI = [3.7;8.5]), the existence of other associated lesions or fracture (RR = 1.8;95% CI = [1.1;3.1]), energy of the trauma (RR = 2.3;95% CI = [1.3;4.4]) and type III classification of Tscherne (RR = 0.3;95% CI = [0.2;0.6]). After multivariate analysis, factors that remained significantly associated with the failure of consolidation were: the existence of diastasis > 2 mm (OR = 7.6;95% CI = [2.2;25.6)), the Body Mass Index (BMI) > 25 (OR = 1.3;95% CI = [1.1 - 1.6]) and the existence of other bone lesion (OR = 4.3;95% CI = [1.4 - 18.9]). Conclusion: BMI greater than 25, the existence of an interfragmentary gap of more than 2 mm and existence of other bone lesions are significant risk factors for nonunion in humerus shaft fractures. The traditional treatment, common singular factor to the African environment, should not be ignored. Control of these predictors is necessary in carrying out the treatment of humerus shaft fractures.

Intramedullary bone pedestal formation contributing to femoral shaft fracture nonunion:A case report and review of the literature

BACKGROUND Femoral shaft fracture is a commonly encountered orthopedic injury that can be treated operatively with a low overall delayed/nonunion rate.In the case of delayed union after antegrade or retrograde intramedullary nail fixation,fracture dynamization is often attempted first.Nonunion after dynamization has been shown to occur due to infection and other aseptic etiologies.We present a unique case of diaphyseal femoral shaft fracture nonunion after dynamization due to intramedullary cortical bone pedestal formation at the distal tip of the nail.CASE SUMMARY A 37-year-old male experienced a high-energy trauma to his left thigh after coming down hard during a motocross jump.Evaluation was consistent with an isolated,closed,left mid-shaft femur fracture.He was initially managed with reamed antegrade intramedullary nail fixation but had continued thigh pain.Radiographs at four months demonstrated no evidence of fracture union and failure of the distal locking screw,and dynamization by distal locking screw removal was performed.The patient continued to have pain eight months after the initial procedure and 4 mo after dynamization with serial radiographs continuing to demonstrate no evidence of fracture healing.The decision was made to proceed with exchange nailing for aseptic fracture nonunion.During the exchange procedure,an obstruction was encountered at the distal tip of the failed nail and was confirmed on magnified fluoroscopy to be a pedestal of cortical bone in the canal.The obstruction required further distal reaming.A longer and larger diameter exchange nail was placed without difficulty and without a distal locking screw to allow for dynamization at the fracture site.Post-operative radiographs showed proper fracture and hardware alignment.There was subsequently radiographic evidence of callus formation at one year with subsequent fracture consolidation and resolution of thigh pain at eighteen months.CONCLUSION The risk of fracture nonunion caused by intramedullary bone pedestal formation can be mitigated with the use of maximum length and diameter nails and close follow up.

Successful Treatment with a Weekly Injection of Teriparatide for the Nonunion of a Distal Humerus Fracture

A distal humerus fracture nonunion is one of the complications with which we should be vigilant. It requires an open reduction and rigid internal fixation. However, treatment with an operative procedure is difficult because the small bones involved in distal humerus fracture nonunion or if osteoporosis is present. And an improvement in the function of the elbow joint is not satisfied because of a postoperative elbow joint contracture. Furthermore, the risk of anesthesia to elderly patients restricts the use of an operation for treatment. A weekly injection of teriparatide has the ability to stimulate bone formation. We present a case of an 87-year-old woman treated with a weekly injection of teriparatide for the nonunion of a distal humerus fracture.

Radiographic evaluation of vascularity in scaphoid nonunions:A review

Scaphoid fractures,particularly those that occur more proximally,are unreliable in achieving union due to the retrograde blood supply of the scaphoid bone.Vascular compromise is associated with the development of nonunions and avascular necrosis of the proximal pole.Due to the tenuous blood supply of the scaphoid,it is imperative that the vascularity be assessed when creating diagnostic and treatment strategies.Early detection of vascular compromise via imaging may signal impending nonunion and allow clinicians to perform interventions that aid in restoring perfusion to the scaphoid.Vascular compromise in the scaphoid presents a diagnostic challenge,in part due to the non-specific findings on plain radiographs and computed tomography.Magnetic resonance imaging techniques have dramatically improved our ability to assess the blood supply to the scaphoid and improve time to intervention.This review aims to summarize these advances and highlights the importance of imaging in assessing vascular compromise in scaphoid nonunion and in reperfusion following surgical intervention.

Effects of bone marrow mesenchymal stem cell combined with platelet-rich plasma treatment of bone nonunion after long bone fracture surgery on bone metabolism and cytokines

Objective: To study the effects of bone marrow mesenchymal stem cell combined with platelet-rich plasma treatment of bone nonunion after long bone fracture surgery on bone metabolism and cytokines. Methods: Patients who were treated in our hospital due to bone nonunion after long bone fracture surgery between March 2011 and October 2017 were selected and randomly divided into two groups, combined group received bone marrow mesenchymal stem cell combined with platelet-rich plasma therapy, and control group received bone marrow mesenchymal stem cell therapy. The levels of bone metabolism markers and growth cytokines in serum as well as the expression of bone metabolism-related signal molecules in peripheral blood were determined before treatment and 1 month after treatment. Results: Compared with those of same group before treatment, serum PINP, OPG, BALP, VEGF, TGF-β1, IGF-I, IGF-II and bFGF levels as well as peripheral blood Runx2, Wnt1, Wnt3a and β-catenin expression intensity of both groups of patients significantly increased whereas serum β-CTX and RANKL levels as well as peripheral blood NOX4 and NF-κB expression intensity significantly decreased after treatment, and serum PINP, OPG, BALP, VEGF, TGF-β1, IGF-I, IGF-II and bFGF levels as well as peripheral blood Runx2, Wnt1, Wnt3a and β-catenin expression intensity of combined group after treatment were higher than those of control group whereas serum β-CTX and RANKL levels as well as peripheral blood NOX4 and NF-κB expression intensity were lower than those of control group. Conclusion: Bone marrow mesenchymal stem cell combined with platelet-rich plasma treatment of bone nonunion after long bone fracture surgery can be more effective than bone marrow mesenchymal stem cell monotherapy to improve the bone metabolism and increase the cytokines.

Treatment of supracondylar nonunions of the femur

To evaluate the result of dynamic condylar screw (DCS) and iliac bone autograft for treating supracondylar nonunions.Methods For 18 supracondylar nonunions,DCS was used as the internal fixation device.For patients with severe osteoporosis or with nonunion site close to the artificial surface,the head of the buttress plate was added,making the screws to fixate easily.Iliac bone autograft including iliac block and scum of spongy bone was used in order to fully arouse the inductive and conductive effect of the graft.Continuous postoperative passive motion (CPM) was performed for a short period,and the active and passive motion were intensively advised for one year long.The cases were followed up from 12 to 70 months (mean 34 months).Results All cases were healed,with average healing time of five months (3～6 months).The motion range for the knee joint was increased from 73 degrees (5～135 degrees) to 97 degrees (30～135 degrees).Excellent and good results were achieved in 13 cases,satisfactory in four and poor in one.Conclusion DCS with rigid fixation and compression effect,combined with porous condylar plate if necessary,with iliac bone autograft and long period of post-operative exercises of the knee joint,provides one efficacious technique for treating the supracondylar non-unions of the femur.11 refs,2 figs.

Nickel-Titanium swan-like memory connector: a new tool to treat humeral shaft nonunion

Objective: To explore a new strategy to treat humeral shaft nonunion efficiently. Methods: In the light of mechanical characteristics of Nickel Titanium memory and the anatomic morphology of humeral shaft, we designed the swan like shape memory alloy connector (SMC). SMC was clinically applied in treating 55 cases of humeral shaft nonunion. Success rate of nonunion repair, reinterventions, complications, range of motion, and patient satisfaction were evaluated. Results: Fifty five humeral shaft nonunion patients were treated with autogenous bone grafting and SMC internal fixation. The average follow up period was 32 months. In 50 patients with complete follow up data, 49 were recovered from nonunion by lamellar bone healing. The excellent and good rate was 98%; one patient suffering from re fracture in a fall refused further treatment. Neither infection nor re fracture after SMC extraction or joint dysfunction was found in the whole group. Conclusion: SMC facilitates safe internal fixation and bone grafting; its memory biomechanic properties promote osteosynthesis, resulting in accelerated and high quality healing of humeral shaft nonunion. SMC internal fixation with bone grafting is creative, efficient and promising in treating humeral shaft nonunion.

Treatment of Scaphoid Nonunion: Pedicled Vascularized Bone Graft vs. Traditional Bone Graft

The clinical results of the application of pedicled vascularized bone graft(VBG) from Lister's tubercle vs. traditional bone graft(TBG) were evaluated and compared. Thirteen cases of symptomatic scaphoid nonunion were treated between January 2011 and December 2012, including 7 cases subject to VBG and the rest 6 cases to TBG, respectively. Outcomes were assessed by modified Mayo wrist score system. All cases were followed up for an average period of 3.5 months after operation. The results showed that total scores in VBG group were 86.4±9.4 after operation with excellent result in 4 cases, good in 2 and acceptable in one, and those in TBG group were 71.7±9.3 after operation with good result in 2 cases, acceptable in 3 and disappointing in one. Total score of wrist function was significantly improved in VBG group as compared with TBG group(P<0.05). Our study suggests that VBG method is more effective for treating scaphoid nonunion than TBG method.Key words: scaphoid nonunion; Herbert screw; vascularized bone

Three predictive scores compared in a retrospective multicenter study of nonunion tibial shaft fracture

BACKGROUND Delayed union,malunion,and nonunion are serious complications in the healing of fractures.Predicting the risk of nonunion before or after surgery is challenging.AIM To compare the most prevalent predictive scores of nonunion used in clinical practice to determine the most accurate score for predicting nonunion.METHODS We collected data from patients with tibial shaft fractures undergoing surgery from January 2016 to December 2020 in three different trauma hospitals.In this retrospective multicenter study,we considered only fractures treated with intramedullary nailing.We calculated the tibia FRACTure prediction healING days(FRACTING)score,Nonunion Risk Determination score,and Leeds-Genoa Nonunion Index(LEG-NUI)score at the time of definitive fixation.RESULTS Of the 130 patients enrolled,89(68.4%)healed within 9 months and were classified as union.The remaining patients(n=41,31.5%)healed after more than 9 months or underwent other surgical procedures and were classified as nonunion.After calculation of the three scores,LEG-NUI and FRACTING were the most accurate at predicting healing.CONCLUSION LEG-NUI and FRACTING showed the best performances by accurately predicting union and nonunion.

顺行和逆行髓内钉治疗不同部位股骨干骨折的有限元分析

背景:髓内钉治疗股骨干骨折取得了较好的临床疗效,但仍有部分患者并发无菌性骨不连,其原因为机械性不稳定。股骨作为人体最长最大的骨骼,不同部位骨折是否具有不同的生物力学特征,及不同进钉方式对于不同部位骨折端稳定性存在何种影响均研究甚少。目的:分析顺行和逆行髓内钉治疗不同部位股骨干骨折的生物力学特点,评估最佳进钉方式,减少骨不连发生率。方法:选取一名志愿者CT资料导入Mimics 19.0和Geomagic studio 2017软件中进行提取、优化得到右侧股骨三维模型;运用Solidworks 2017软件画出顺行和逆行髓内钉模型并与不同骨折部位股骨干骨折模型按照标准手术技术装配,以STEP格式导入Abaqus 2017软件中设置材料属性参数、边界条件、施加载荷、提交运算,于可视化模块中查看结果。其中上段股骨干骨折顺行和逆行髓内钉分别为A1、A2模型,中段为B1、B2模型,下段为C1、C2模型。结果与结论:(1)A1、B1、C2模型股骨整体应力分布更为均匀,位移、骨折端间隙与成角、股骨近折端骨块内翻均更小;(2)对于上段和中段股骨干骨折,顺行髓内钉具有更好的生物力学效果;对于下段股骨干骨折,逆行髓内钉效果更优。