Application of digital technology in the reconstruction of orbital fractures: research progress / 中华创伤杂志

Orbital fracture often leads to facial collapse, diplopia, enophthalmos, and even blindness. Traditional surgery relies on the experiences of physicians to achieve fracture reduction and orbital wall reconstruction, but the repair effect is not satisfactory. In recent years, with the development of digital technology, technologies such as computer-assisted surgery, 3D printing, surgical navigation systems, and intraoperative CT imaging have become increasingly widespread in the field of orbital reconstruction. Such techniques can avoid dependence on physicians′ experiences and make it easy for estimating and positioning the implantation sites, which subsequently contributes to better surgery efficiency and precise reconstruction of the orbit, improving aesthetics and visual function of patients. To this end, the authors reviewed the recent progress in application of digital technology for orbital fracture reconstruction, so as to provide reference and theoretical basis for clinical practice.

Open reduction and internal fixation assisted by computer virtual surgery in the treatment of complex proximal humeral fracture / 中华创伤杂志

Objective:To investigate the effect of open reduction and internal fixation assisted by computer virtual surgery in the treatment of complex proximal humeral fracture.Methods:A retrospective case series study was performed on clinical data of 36 patients with complex proximal humeral fracture admitted to Dongfang Hospital Affiliated to Tongji University from January 2018 to June 2020. There were 13 males and 23 females, aged 22-86 years [(56.4±4.8)years]. They were all closed fractures. According to Neer classification, there were 20 patients with three-part fractures and 16 with four-part fractures. Precise pre-surgical designs made by using the digital orthopedic surgery planning system of the E-3D were applied to assist the implementation of precise fracture reduction and internal fixation with the locking plate. The fracture healing was observed. The effect of the real surgery assisted by the virtual surgical designs was assessed by comparing the humeral neck shaft angle and humeral head height measured at the virtual surgery and at day 1 after the real surgery. The humeral neck shaft angle, humeral head height, shoulder range of motion (abduction, external rotation and forward flexion), Constant shoulder function score and visual analogue score (VAS) were recorded at 1 day, 3 months and 12 months after the real surgery. The stability of the medial column was assessed at 1 day after the real surgery. The complications were recorded.Results:All patients were followed up for 12-38 months [(18.5±1.8)months]. The fracture showed bony union in all patients with the union time of 6.6-17.2 weeks [(10.2±1.0)weeks]. The humeral neck shaft angle and humeral head height showed no significant differences measured at the virtual surgery and at 1 day after the real surgery, and were also not significant different at 1 day, 3 months and 12 months after the real surgery (all P>0.05). At 3 months and 12 months after the real surgery, the shoulder abduction [(119.4±11.8)°, (155.3±13.7)°], external rotation [(37.6±6.3)°, (46.8±7.4)°], forward flexion [ (94.8±10.2)°, (126.9±1.6)°] and Constant function score [(66.8±8.4)points, (82.4±9.6)points] were all higher than those at 1 day after the real surgery [(53.8±4.5)°, (21.6±3.3)°, (44.6±7.8)°, (34.3±6.1)points], while the VAS [(4.1±0.5)points, (1.2±0.2)points] was lower than that at 1 day after the real surgery [(8.3±1.4)points] (all P<0.05). The medial column was stable in 34 patients and unstable in 2 at 1 day after the real surgery. Complications included screw cutting out in the articular surface in 1 patient and humeral head necrosis in 1. Conclusion:Treatment of complex proximal humeral fractures with open reduction and internal fixation assisted by computer virtual surgery is conducive to maintaining reduction effect, promoting shoulder joint function, relieving pain and reducing complications.

Navigation-assisted valgus stress method can avoid over correction of high tibial osteotomy / 中华骨科杂志

Objective:To explore the role of navigation-assisted valgus stress method in avoiding excessive correction of lower limb mechanical axis after high tibial osteotomy (HTO).Methods:A retrospective study was carried out on osteoarthritis (OA) patients who were treated with HTO for medial compartment pain of knee from January 2020 to March 2022 in the Department of Joint Surgery, Shanghai Changhai Hospital, the First Affiliated Hospital of Naval Medical University. According to the different ways of confirming alignment during operation, they were divided into computer navigation assisted valgus stress HTO group (referred to as navigation group) and traditional rod fluoroscopy HTO group (referred to as traditional group). There were 28 patients in the navigation group, 10 males and 18 females, with age of 54.4±9.1 years (range, 41-73 years) and body mass index of 26.1±3.3 kg/m 2 (range, 19.8-35.2 kg/m 2); There were 30 patients in the traditional group, 13 males and 17 females, aged 56.9±8.5 years (range, 40-70 years), with a body mass index of 25.7±4.0 kg/m 2 (range, 19.2-32.9 kg/m 2). Measuring the mechanical femoral tibial angle (mFTA), joint line convergence angle (JLCA), medial proximal tibial angle (MPTA), Lysholm score and Hospital for Special Surgery (HSS) score before operation and at the last follow-up of the two groups, and conduct statistical analysis. Results:Both groups were followed up. The follow-up time of navigation group and traditional group was 21.3±8.7 months and 22.5±7.6 months, respectively, with no significant difference ( t=0.53, P=0.596). There were significant differences between the two groups in the amount of mechanical axis correction (ΔmFTA) and the amount of bone correction (ΔMPTA) ( t=2.09, P=0.041; t=2.58, P=0.012), while there was no significant difference in ΔJLCA ( t=0.32, P=0.753). In the navigation group, there were 9 cases (32%) of undercorrection, 17 cases (61%) with acceptable alignment, and 2 cases (7%) with over correction, while in the traditional group, there were 5 cases (17%) with under correction, 13 cases (43%) with acceptable alignment, and 12 cases (40%) with over correction. There was significant difference in the distribution rate of alignment between the two groups ( P=0.012), and the rate of overcorrection in the navigation group was significantly lower than that in the control group (7% vs. 40%, P=0.005). The intra group correlation coefficient between the navigation correction mechanical axis and ΔmFTA was 0.787. There was no significant difference in Lysholm score and HSS score between the two groups before and after surgery (all P>0.05), and they were significantly improved after operation (all P<0.05). Conclusion:Navigation-assisted valgus stress method HTO is reliable, which can accurately achieve the target alignment, reduce the incidence of over correction, and obtain good clinical results.

Application of preoperative three-dimensional reconstruction planning in total hip arthroplasty for development dysplasia of the hip secondary to osteoarthritis / 中华骨科杂志

Objective:To investigate the clinical efficacy of preoperative three-dimensional (3D) reconstruction planning in total hip arthroplasty for development dysplasia of the hip secondary to osteoarthritis.Methods:A total of 80 patients with osteoarthritis secondary to Crowe I-III developmental dysplasia of the hip who underwent primary unilateral total hip arthroplasty from October 2019 to March 2021 were retrospectively analyzed, including 18 males and 62 females and the mean age was 55.7±10.4 years (range 41-72 years). Forty patients in the 3D group, the prosthesis type and installation angle were planed on the 3D reconstruction software based on the full-length CT scan data of the lower limbs, and the length difference of the lower limbs and hip offset were calculated. Forty patients in the control group underwent preoperative planning using conventional film measurement, and lower limb length was judged based on the preoperative measurement data and intraoperative comparison of both lower limbs. The difference of postoperative leg length, hip offset, hip function score, operating time, intraoperative blood loss, and incidence of complications were compared between the two groups.Results:All 80 patients completed the surgery successfully and the follow-up time was up to 3 months after operation. The 3D group was better than the control group in operation time (70.9±7.7 min vs. 81.6±13.3 min, t=-4.91, P<0.001), the difference of postoperative lower limb length (2.78±1.31 cm vs. 5.35±2.15 cm, t=-5.74, P<0.001), and hip function score at 1 week after operation (75.67±3.35 vs. 67.35±4.21, t=12.33, P=0.002), with statistically significant differences. In the 3D group, 95% of acetabular prosthesis and 90% of femoral stem components were consistent with the planned model, while the rate were only 75% and 68% in the control group, and the difference was statistically significant (χ 2=7.51, P=0.023; χ 2=14.92, P=0.005). There were no intraoperative complications such as vascular and nerve injury, and no postoperative complications such as dislocation or periprosthetic infection in all 80 patients. Conclusion:3D preoperative planning assisted total hip arthroplasty in the treatment of Crowe I-III developmental dysplasia of the hip secondary to osteoarthritis can improve the accuracy of the operation, and has a good clinical effect on restoring the leg length and hip offset.

Long Term Outcomes of Computer-Navigated Lateral Opening Wedge Distal Femoral Osteotomy for Lateral Compartment Knee Arthrosis / Resultados a longo prazo de osteotomia varizante femoral distal (OVFD) com cunha de abertura lateral para artrose do compartimento lateral do joelho utilizando navegação computadorizada

Abstract Objective The primary aim of the present study was to evaluate the long-term outcomes including survivorship of computer navigated distal femoral lateral opening wedge osteotomy (DFLOWO). The secondary aim was to identify the potential factors that may influence its survivorship. Methods A retrospective analysis of prospectively collected data for patients with lateral compartment arthritis who underwent navigated DFLOWO from December 2006 to November 2012 was performed. The International Knee Documentation Committee (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS) scores were analyzed for outcome measures. Conversion to arthroplasty during the follow-up was the end point. Results A total of 19 DFLOWOs were performed in 17 patients with a mean age of 46.6 ± 6.5 years formed the study cohort. The coronal alignment was corrected from a mean of 7.1° (2-11°) valgus to a mean of 2.1° (0.5°-3°) varus. The IKDC scores improved from mean of 39 preoperatively to 53 at the mean long-term follow-up of 9.1 years. The mean KOOS scores at the long-term follow-up were pain 71, symptoms 56, activities of daily living 82, sports and recreation 59, quality of life 43. Survivorship of the DFLOWO was 78.9% at a follow-up of 9.1 years. Presence of ≥ grade 2 according to the International Cartilage Repair Society (ICRS) cartilage degeneration in the medial compartment of the knee and >7° preoperative valgus deformity were strongly correlated with conversion to total knee arthroplasty (TKA) at the long-term follow-up (r= 0.66). ConclusionsComputer navigated DFLOWO has satisfactory clinical outcomes and 79% survivorship in long-term follow-up. Presence of more than ICRS ≥ grade 2 degenerative changes in the medial compartment of knee with > 7° preoperative valgus deformity negatively affects the survivorship of DFLOWO in the long-term follow-up.

Resumo Objetivo O objetivo principal do presente estudo foi avaliar os resultados a longo prazo, incluindo a sobrevivência em Osteotomia Varizante Femoral Distal com Cunha de Abertura Lateral (OVFD-CAL) utilizando navegação computadorizada. O objetivo principal do presente estudo foi avaliar os resultados a longo prazo, incluindo a sobrevivência. Métodos Foi realizada uma análise retrospectiva dos dados coletados prospectivamente de pacientes com artrite do compartimento lateral submetidos a OVFD-CAL por navegação de dezembro de 2006 a novembro de 2012. As pontuações International Knee Documentation Committee (IKDC, na sigla em inglês) e Knee Injury and Osteoarthritis Outcome Score (KOOS, na sigla em inglês) foram analisadas para medição de resultados. Conversão para artroplastia durante o acompanhamento foi o ponto final. Resultados Um total de 19 OVFD-CAL foram realizados em 17 pacientes com média de idade de 46,6 ± 6,5 anos formaram a coorte do estudo. O alinhamento coronal foi corrigido a partir de uma média de 7,1° (2-11°) de valgo para uma média de 2,1° (0,5°-3°) de varo. As pontuações do IKDC melhoraram de uma média pré-operatória de 39 para 53 no acompanhamento de médio de longo prazo de 9,1 anos. Os escores do KOOS no acompanhamento a longo prazo foram: dor 71, sintomas 56, atividades da vida diária 82, esportes e recreação 59, qualidade de vida 43. A sobrevivência do OVFD-CAL foi de 78,9% em um acompanhamento de 9,1 anos. Presença de degeneração da cartilagem segundo a Sociedade Internacional de Reparação de Cartilagem (International Cartilage Repair Society [ICRS, na sigla em inglês])≥ grau 2 no compartimento medial do joelho e deformidade pré-operatória em valgo > 7° fortemente correlacionado com a conversão para artroplastia total do joelho (ATJ) no acompanhamento a longo prazo (r - 0,66). ConclusõesA OVFD-CAL por navegação computadorizada apresentou resultados clínicos satisfatórios e sobrevida de 79% no acompanhamento a longo prazo. Presença de alterações degenerativas ICRS ≥ grau 2 no compartimento medial do joelho com > 7° de deformidade pré-operatória em valgo afeta negativamente a sobrevivência da OVFD-CAL no acompanhamento de longo prazo.

Perspectivas em cirurgia robótica: a visão do cirurgião / Robotic surgery: the surgeon's perspective

Introdução: Avaliar os níveis de conhecimento, interesse e treinamento dos cirurgiões inscritos no Colégio Brasileiro dos Cirurgiões (CBC) da cidade de Porto Alegre, Rio Grande do Sul, em relação à cirurgia robótica. Métodos: Estudo transversal, baseado em informações coletadas por meio de questionário enviado via plataforma digital para potenciais participantes. O formulário continha perguntas estruturadas e autoaplicáveis, a fim de caracterizar o perfil profissional, capacitação em cirurgia minimamente invasiva, conhecimento, opinião e treinamento específico em cirurgia robótica. Resultados: Dos 146 membros inscritos no CBC na cidade de Porto Alegre, 99 (67,8%) responderam ao questionário. Houve predomínio do sexo masculino (88%) e a mediana de idade dos participantes foi de 48 anos. Os procedimentos videolaparoscópicos ou vídeo-assistidos foram maioria na rotina dos cirurgiões. Da totalidade da amostra, a maior parte (78%) já assistiu ao menos um procedimento robótico, e um terço (n = 30) já realizou algum tipo de treinamento ou simulação em cirurgia robótica. Entre os que não realizaram, dois terços pretendem se qualificar no futuro. Apenas 10% dos cirurgiões possuem certificação na área. Conclusão: A maioria dos cirurgiões respondentes inscritos no CBC em Porto Alegre tem em sua rotina predominância de procedimentos minimamente invasivos e acredita que a plataforma robótica será o futuro da cirurgia. Embora ainda não disponível na maioria dos serviços gaúchos, espera-se que o desenvolvimento de novas plataformas e a redução dos custos envolvidos na aquisição de equipamento e de capacitação do cirurgião facilitem a disseminação dessa tecnologia.

Introduction: To assess the practical knowledge, interest, and training levels of surgeons enrolled in the Brazilian College of Surgeons (CBC) of the municipality of Porto Alegre, Rio Grande do Sul, regarding robotic surgery. Methods: Cross-sectional study, based on information collected with a questionnaire sent to potential participants via digital platform. The form contained structured and self-administered questions, to characterize their professional profile, skills in minimally invasive surgery, knowledge, opinion, and specific training in robotic surgery. Results: Of the 146 members enrolled in the CBC of the municipality of Porto Alegre, 99 (67.8%) responded to the questionnaire. Most were males (88%) with a mean age of 48 years. Video-laparoscopic or video-assisted procedures were the most frequent in the participants' practice. Of the sample, most (78%) already watched at least one robotic surgery, and one third (n = 30) had already completed some sort of training or simulation course in robotic surgery. Among those who did not, two thirds intend to pursue formal training in the future. Only 10% of participating surgeons are certified in the area. Conclusion: Most responding surgeons enrolled in the CBC in Porto Alegre perform mostly minimally invasive procedures daily and believe that the robotic technology will be the future of surgery. Although not yet available in most services of the state of Rio Grande do Sul, it is expected that the development of new platforms and the reduction of costs involved in equipment acquisition and surgical training will facilitate the dissemination of this technology.

Single oblique lumbar interbody fusion with robot-assisted posterior internal fixation for lumbar degenerative diseases / 中国骨伤

OBJECTIVE@#To investigate the efficacy of single oblique lumbar interbody fusion(OLIF) with robot-assisted posterior internal fixation for the treatment of lumbar degenerative diseases.@*METHODS@#The clinical data of 67 patients with lumbar degenerative diseases treated from September 2019 to December 2020 was retrospectively analyzed. According to different surgical methods, the patients were divided into traditional group and robot group. The traditional group received traditional OLIF with posterior fluoroscopy percutaneous nail fixation, and the robot group received OLIF with robot-assisted posterior internal fixation. There were 33 patients in traditional group, including 13 males and 20 females, aged from 44 to 82 years old with an average of (59.7±9.1) years; and 34 cases in robot group, including 7 males and 27 females, aged from 45 to 81 years old with an average of(61.6±8.8) years. The operation time, fluoroscopy time, intraoperative blood loss, postoperative out of bed time and hospital stay were recorded. The visual analogue scale (VAS) of low back pain and Oswestry Disability Index(ODI) were compared before operation and 3 days, 3 months after operation between two groups. The accuracy of nail placement was evaluated by postoperative CT scan.@*RESULTS@#Both groups of patients successfully completed the operation and were followed up for more than 3 months. The operation time, fluoroscopy time, intraoperative blood loss, postoperative out of bed time and hospital stay in traditional group were(299.85±15.79) min, (62.58±10.83) min, (118.33±10.80) ml, (2.5±0.7) d, (9.67±2.13) d;and robot group was(248.53±14.22) min, (19.47±3.51) min, (115.74±9.86) ml, (2.3±0.6) d, (9.44±1.93) d, respectively. The symptoms of postoperative low back pain, lower limb pain and numbness were significantly improved in all patients. The operation time and fluoroscopy time in robot group were significantly less than those of traditional group. There was no significant difference in intraoperative blood loss, postoperative out of bed time, hospital stay, VAS and ODI before and after operation (P>0.05). The accuracy of nail placement in robot group was 98.8% (2/160), which was higher than 89.9% (16/158) in traditional group.@*CONCLUSION@#Treatment of lumbar degenerative diseases with single body position OLIF with robot-assisted posterior minimally invasive internal fixation has less operation time and fluoroscopy time, high nail placement accuracy and accurate surgical effect, which is worthy to be popularized in clinic.

Accuracy and safety of robot assisted pedicle screw placement / 中国骨伤

OBJECTIVE@#To investigate the accuracy and safety of pedicle screw placement assisted by orthopedic robot and C-arm fluoroscopy.@*METHODS@#The clinical data of 36 patients with spinal diseases underwent surgical treatment from January 2019 to August 2020 was retrospectively analyzed. Among them, 18 cases were implanted pedicle screws assisted by orthopaedic robot(observation group), including 12 males and 6 females, aged from 16 to 61 years with an average of (38.44±3.60) years;there were 1 case of adolescent scoliosis, 1 case of spinal tuberculosis, 7 cases of lumbar spondylolisthesis, 4 cases of thoracic fracture and 5 cases of lumbar fracture. Another 18 cases were implanted pedicle screws assisted by C-arm fluoroscopy(control group), including 10 males and 8 females, aged from 18 to 58 years with an average of (43.22±2.53) years;there were 1 case of adolescent scoliosis, 6 cases of lumbar spondylolisthesis, 6 cases of thoracic fracture and 5 cases of lumbar fracture. The intraoperative fluoroscopy times, nail placement time and postoperative complications were recorded in two groups. CT scan was performed after operation. The Gertzbein-Robbins standard was used to evaluate the accuracy of pedicle screw placement which was calculated.@*RESULTS@#The number of intraoperative fluoroscopy in observation group was(6.89±0.20) times, which was significantly higher than that in control group(14.00±0.18)times(P<0.05). The placement time of each screw in observation group was(2.56±0.12) min, which was significantly different from that in control group(4.22±0.17) min (P<0.05). One case of incision infection occurred in control group after operation, and recovered after active dressing change. During the follow-up period, no serious complications such as screw loosening and fracture occurred in two groups, and there was no significant difference in complications between two groups(P>0.05). A total of 107 screws were placed in observation group, including 101 screws in class A, 4 in class B, 2 in class C, 0 in class D and 0 in class E, the accuracy rate of pedicle screw placement=[(number of screws in class A+B) / the number of all screws placed in the group] ×100%=98.1%(105/107); and a total of 104 screws were placed in control group, including 90 screws in class A, 4 in class B, 5 in class C, 5 in class D and 0 in class E, the accuracy rate of pedicle screw implantation=[(number of screws in class A+B/the number of all screws placed in the group]×100%=90.3% (94/104); there was significant difference between two groups (P<0.05).@*CONCLUSION@#Orthopaedic robot assisted pedicle screw placement has the advantages of less fluoroscopy times, shorter screw placement time and higher accuracy, which can further improve the surgical safety and has a broad application prospect in the orthopaedic.

Efficacy of robot-assisted arthroscopic anterior cruciate ligament reconstruction / 中华创伤杂志

Objective:To compare the clinical efficacy of robot-assisted and simple arthroscopic reconstruction of anterior cruciate ligament (ACL).Methods:A retrospective cohort study was conducted to analyze the clinical data of 37 patients with ACL tear admitted to Honghui Hospital of Xi′an Jiaotong University from January 2020 to September 2020. There were 24 males and 13 females, aged 16-45 years［(30.7±9.8)years］. A total of 17 patients were treated by robot-assisted ACL reconstruction (robot-assisted group), and 20 patients by simple arthroscopic ACL reconstruction (simple arthroscopy group). The operation time, number of guide wire drilling, positional accuracy of bone tunnel (distance between the central point of bone tunnel and ideal anatomical point) and perioperative complications were compared between the two groups. Knee stability was evaluated by Lachman test and KT-2000 measurement, and knee function by Lysholm score, International Knee Documentation Committee (IKDC) score and range of motion of joint flexion and extension before operation, at 4 months after operation and at the last follow-up.Results:All patients were followed up for 12-18 months［(13.1±4.1)months］. The operation time in robot-assisted group was (83.8±11.3)minutes, significantly longer than (50.4±9.1)minutes in simple arthroscopy group ( P<0.01). The number of guide wire drilling in robot-assisted group was (2.2±0.5)times, less than (2.5±0.4)times in simple arthroscopy group ( P<0.05). The distance between the central point of bone tunnel and ideal anatomical point was (1.3±0.3)mm in robot-assisted group, not significantly different from (1.4±0.3)mm in simple arthroscopy group ( P>0.05). There were no perioperative complications in both groups. The two groups showed no significant differences in Lachman test, KT-2000 measurement, Lysholm score, IKDC score and range of motion of joint flexion and extension before operation, at 4 months after operation and at the last follow-up (all P>0.05). The above indices in both groups were significantly improved at 4 months after operation and at the last follow-up as compared with those before operation (all P<0.01), and both groups showed no significant difference in the above indexes at 4 months after operation and at the last follow-up as compared with those before operation (all P>0.05). Conclusion:Compared with simple arthroscopic ACL reconstruction, robot-assisted ACL reconstruction can prepare a bone tunnel once with good location and direction in one time and achieve similar results in stability and functional recovery of the joint except for slightly longer operation time.

Efficacy of navigation-assisted cosmetic incision for reduction and internal fixation in treating unilateral type B zygomatic fracture / 中华创伤杂志

Objective:To analyze the clinical effect of navigation-assisted cosmetic incision for reduction and internal fixation in treating unilateral B-type zygomatic fracture.Methods:A retrospective cohort study was performed on clinical data of 35 patients with unilateral type B zygomatic fracture treated from January 2018 to December 2019 in First Affiliated Hospital of Fujian Medical University. There were 20 males and 15 females at age range of 5-62 years [(38.7±11.3)years]. Navigation-assisted cosmetic incision for reduction and internal fixation was performed for 17 patients (navigation group), and empirical incision to reduction and internal fixation was performed for 18 patients (convention group). The length of bony zygomatic process (zygomatic process) and width of zygomatic temporal point (frontal width) of the bilateral zygomatic bone were measured on the horizontal axis of CT at 1 week after operation. The absolute values of the difference of bony zygomatic process degree and frontal bony width between affected side and the healthy side were compared between the two groups. The patients′ satisfaction and occurrence of complications such as lower eyelid ectropion, incision infection and facial nerve injury were compared between the two groups at half a year after operation.Results:All patients were followed up for 6-24 months [(9.3±1.2)months]. The absolute difference of bony zygomatic process was 0.60(0.25, 0.85) mm in navigation group, and was 0.75 (0.20, 1.98)mm in convention group ( P>0.05). The absolute difference of frontal bony width was (0.37±0.11)mm in navigation group, and was (2.47±0.63)mm in convention group ( P<0.01). Satisfaction rates by both objective evaluation and subjective evaluation in navigation group were better than that in convention group at half a year after operation (both P<0.05). Navigation group showed lower eyelid ectropion in 1 patient and incision infection in 1 patient. Convention group showed facial nerve injury in 1 patient and incision infection in 2 patients. There was no significant difference in the incidence of complications between navigation group [12%(2/17)] and conventional group [17%(3/18)] ( P>0.05). Conclusion:For unilateral type B zygomatic fracture, navigation-assisted cosmetic incision for reduction and internal fixation can more accurately restore the frontal width, and improve satisfaction rate as compared with empirical reduction and internal fixation.

Axis pedicle screwing assisted by intraoperative 3-D navigation versus freehand axis pedicle screwing in treatment of Hangman fracture / 中华创伤骨科杂志

Objective:To compare the therapeutic results between axis pedicle screwing assisted by intraoperative 3-D navigation and freehand axis pedicle screwing in the treatment of Hangman fracture.Methods:A retrospective analysis was performed of the 64 patients with Hangman fracture who had received posterior axis pedicle screwing at Department of Spinal Surgery, The Sixth Hospital of Ningbo from May 2014 to December 2019. According to the placement methods of axis pedicle screws, they were divided into a navigation group ( n=34, subjected to axis pedicle screwing assisted by intraoperative 3-D navigation) and a freehand group ( n=30, subjected to freehand axis pedicle screwing). Pedicle screw placement time, operation time, intraoperative bleeding, fluoroscopy time, hospital stay, total hospitalization cost and complications were recorded and compared between the 2 groups. The accuracy of axis pedicle screw placement was evaluated according to the postoperative cervical CT and screw grading criteria proposed by Park et al. At admission, 3 months postoperation, and the last follow-up, neurological function of the patients was evaluated by modified Japanese Orthopedic Association (mJOA) score, neck pain was evaluated by visual analogue scale (VAS), and C2/3 vertebral body angulation and C2 forward displacement were measured. The clinical efficacy was evaluated by Moon grading at the last follow-up. Results:The navigation group and the freehand group were comparable due to insignificant differences between them in the preoperative general data ( P>0.05). The accuracy of screw placement in the navigation group (98.2%, 54/55) was significantly higher than that in the freehand group (85.2%, 46/54) ( P<0.05). The screw placement time, operation time, fluoroscopy time and total hospitalization cost in the navigation group were significantly more than those in the freehand group ( P<0.05). Vertebral artery injury occurred in 3 cases in the freehand group. Screw loosening, screw breakage or rod breakage occurred in none of the patients after operation. There was no significant difference between the 2 groups in the intraoperative bleeding, hospital stay or follow-up time ( P>0.05). In both groups, the VAS score, mJOA score, C2/3 vertebral body angulation and C2 forward displacement were significantly improved at 3 months postoperation and the last follow-up compared with those at admission ( P<0.05), but there was no significant difference between the 2 groups in the contemporary comparisons ( P>0.05). At the last follow-up, Moon grading in the navigation group was significantly better than that in the freehand group ( P<0.05). Conclusion:In the treatment of Hangman fracture, compared with freehand screw placement, axis pedicle screwing assisted by intraoperative 3-D navigation can improve accuracy and safety of screw placement and reduce postoperative complications, leading to better clinical efficacy.

Application and research progress of intelligent accuracy technological aids in total knee arthroplasty / 中华创伤杂志

Total knee arthroplasty (TKA) is an effective treatment for end-stage knee disease, with the postoperative alignment, component position, soft tissue balance, and prosthesis matching being key factors for the success of TKA. In order to achieve more accurate postoperative alignment and component position, better soft tissue balance and prosthesis matching for longer prosthesis longevity, better postoperative function and higher patient satisfaction, various intelligent accuracy technological aids such as computer assisted navigation (CAN), patient specific instrumentation (PSI), surgical robots, microsensors, customized implants (CI) and personalized 3D preoperative planning have emerged and are given high expectation. In this paper, the authors review the application and research progress of the above technological aids mainly from aspects of alignment, component position, clinical outcomes and cost analysis, so as to provide a reference for the application of related technological aids in TKA.

Treatment of acromioclavicular joint dislocation with double Endobutton internal fixation assisted by orthopaedic robot / 中华骨科杂志

Objective:To investigate the early clinical effects of orthopedic surgery robot-assisted double Endobutton titanium plate internal fixation in the treatment of fresh acromioclavicular joint dislocation.Methods:Thirty-nine patients with fresh acromioclavicular joint dislocation were included from January 2020 to January 2022. A total of 19 patients were treated with double Endobutton suspension internal fixation assisted by the domestic third-generation orthopaedic surgical robot (TiRobot ? 2.0) Dimensity system. There were Rockwood type III in 11 cases, type IV in 8 cases. Twenty cases were treated with conventional incision double Endobutton internal fixation, with Rockwood type III in 13 cases, type V in 7 cases. The operation duration, blood loss volume, incision length and hospitalization time were compared between the two groups. The following CT parameters of acromioclavicular joint at 2 days and 1 year after operation, distance between distal inferior cortex of clavicle and subacromial cortex, distance between upper and lower endobuttons, horizontal distance between anterior edge of distal clavicle and anterior edge of acromion and diameter of coracoid process and diameter of clavicular tunnel were measured. The visual analogue score (VAS), Constant-Murley shoulder function score and shoulder abduction activity were also evaluated before and at 12 months after operation. Results:The follow-up duration was 10.8±2.4 months in the robot group and 11.5±3.1 months in the routine group. The VAS score of the robot group decreased from 5.3±2.1 to 0.3±0.2 at 12 months after operation ( t=10.46, P=0.014). The Constant-Murley score increased from 55.6±6.4 to 92.0±4.2. The range of shoulder abduction increased from 42.2°±5.4° to 172.6°±6.1° ( t=17.24, P<0.001). The operation duation of the robot group was 74.4±6.6 min, which was longer than that of the conventional group 61.7±7.2 min ( t=5.43, P=0.037). There was no significant difference in VAS score, Constant-Murley score, shoulder abduction activity or CT measurement between the two groups ( P>0.05). During the follow-up, two cases in the robot group had cortical osteolysis on the supraclavicular surface, one case in the conventional group had loss of reduction, one case in the supraclavicular cortical osteolysis, and 4 cases in the cortical defect on the side of the coracoid process tunnel. Conclusion:Orthopedic robot-assisted and conventional incision with double Endobutton titanium plate internal fixation in treating fresh acromioclavicular joint dislocation can achieve satisfied early clinical effects. Accurate establishment of clavicle and coracoid bone tunnel assisted by robot can overcome the defects of bone tunnel deviation in conventional incision operation and can prevent reduction and bone loss. However, robot-assisted and conventional incision Endobutton internal fixation could enlarge bone tunnel.

Preliminary application of navigation-assisted total knee arthroplasty using adjusted restricted kinematic alignment / 中华骨科杂志

Objective:To evaluate the feasibility and clinical outcomes of navigation-assisted total knee arthroplasty (TKA) using adjusted restricted kinematic alignment (arKA).Methods:Data of 14 consecutive cases of OrthoPilot navigation-assisted TKA using arKA from October 2019 to September 2021 were retrospectively analyzed, including 3 males and 9 females. The average age was 67.71±8.96 years with mean body mass index (BMI) 25.94±3.12 kg/m 2. 27 consecutive patients who underwent navigation-assisted TKA using aMA during the same period were assessed as the control group. There were no significant differences in gender, age or BMI between the two groups. Intraoperative parameters including operative duration, tibia resection angle, frontal femoral angle, axial femoral angle, joint line translation, medial and lateral gap in extension and flexion position were recorded. Radiographic parameters including hip-knee-ankle (HKA) angle, coronal femoral component angle (cFCA), coronal tibial component angle (cTCA), sagittal femoral component angle (sFCA) and sagittal tibial component angle (sTCA) were measured. Functional outcomes were assessed by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Hospital for Special Surgery (HSS) score. Surgery-related complications were recorded. Results:All cases were followed up. The mean follow-up of arKA group was 18.57±6.98 months and follow-up of aMA group was 22.15±4.91 months. The intraoperative tibial resection was 3.07°±1.00° in arKA group versus 0.67°±0.56° in aMA group ( P<0.05). The lateral cutting height of tibia was 9.07±1.82 mm in arKA group versus 6.89±2.94 mm in aMA group ( P<0.05). The lateral gap in flexion was 1.71±0.83 mm in arKA group versus 1.04±0.71 mm in aMA group ( P<0.05). The difference of medial-lateral flexion laxity was 1.14±0.86 mm in arKA group versus 0.41±0.75 mm in aMA group ( P<0.05). The postoperative HKA angle was 174.10°±1.63° in arKA group versus 177.12°±2.07° in aMA group ( P<0.05). The cTCA was 87.58°±0.85° in arKA group versus 89.14°±1.23° in aMA group ( P<0.05). The cFCA was 93.10°±1.75° in arKA group versus 90.41°±3.01° in aMA group ( P<0.05). There was no statistical difference between the two groups in sFCA (1.30°±0.82° vs. 1.56°±1.19°), sTCA (87.16°±0.95° vs. 87.79°±1.04°) and femoral notching (7.1% vs. 11.1%). The preoperative HSS score in arKA group was 46.07±4.68 and HSS score at 1 month postoperatively was 73.86±3.48 ( P<0.05). The preoperative HSS score in aMA group was 47.04±4.52 and HSS score at 1 month postoperatively was 74.04±3.57 ( P<0.05). There was no statistical difference between the two groups in WOMAC score (12.93±2.37 vs. 12.63±2.34) and HSS score (86.86±2.74 vs. 86.11±2.95) at 6 months postoperatively. 2 cases (14.3%) in arKA group and 5 cases (18.5%) in aMA group had deep venous thrombosis (χ 2=0.12, P=0.733). Conclusion:Navigation-assisted TKA using arKA offers the surgeons a new alignment option for severe knee deformity with satisfactory clinical outcomes, the arKA technique has advantages in soft tissue protection and gap balance regulation compared to aMA technique.

Rehabilitation of atrophic posterior partial edentulous maxilla with TTPHIL ALL TILT® technique: 3 year follow-up case report / Reabilitação de maxila atrófica posterior parcialmente desdentada com técnica TTPHIL ALL TILT®: relato de caso de acompanhamento de 3 anos

Maxillary sinus pneumatisation pose a grave clinical challenge for implant fixed rehabilitation in posterior maxilla owing to diminished bone volume. This necessitates sinus lift and grafting which increase the duration and cost and possible surgical complications. Pterygoid implant has a greater short term osseointegration and is a proven treatment method for rehabilitation of highly resorbed posterior maxilla. To overcome the limitations of sinus grafting techniques, the current case report describes the use of flapless, tilted and pterygoid implant for restoration of partially edentulous atrophic maxilla eliminating grafting (AU).

A pneumatização do seio maxilar representa um grande desafio clínico para a reabilitação fixa por implante na região posterior da maxila devido ao volume ósseo diminuído. Isso requer elevação do seio e enxerto, fatores que aumentam a duração, o custo e as possíveis complicações cirúrgicas. O implante pterigóide tem uma osseointegração maior em curto prazo e é um método de tratamento comprovado para reabilitação de maxila posterior altamente reabsorvida. Para superar as limitações das técnicas de enxerto de seio, o relato de caso atual descreve o uso de implante sem retalho, inclinado e pterigóide para restauração de maxila atrófica parcialmente edêntula eliminando o enxerto.(AU)

Neuromuscular scoliosis with severe pelvic obliquity: the accuracy of S 2AI screw placement by O-arm three-dimensional CT navigation / 中华骨科杂志

Objectives:To investigate the feasibility of second sacral alar-iliac (S 2AI) screw placement and trajectories index in patients with neuromuscular scoliosis with severe pelvic obliquity; and to explore the accuracy of S 2AI screw placement by O-arm three-dimensional (3D) CT navigation (Medtronic, Minneapolis, MN, USA). Methods:All of 28 patients with neuromuscular scoliosis who underwent posterior long fusion with S 2AI between January 2017 and August 2020 were reviewed, with an average age of 22.2 years old (ranged from 10 to 51 years), and the pelvic obliquity angle was 27.54±9.90° (ranged from 16.2° to 53.6°). Based on 3D CT reconstruction of these specimens, virtual S 2AI screw channels were identified and measured. Entry point was determined by 1 mm inferior and 1 mm lateral to the S 1 dorsal foramen, and virtual S 2AI screw trajectories with maximum length and width were explored by rotating 3D pelvis. The parameters of the determined channels were measured including caudal angulation on the sagittal plane (sagittal angle, SA), lateral angulation on the transverse plane (transverse angle, TA) and the maximal length of the channel (maximal length, ML). The accuracy of screw placement was evaluated by postoperative pelvic CT scan. Results:All of the virtual S 2AI screw trajectories can be reconstructed. The screw trajectory parameters were shown as follows: SA was 30.20°±21.94° and 50.94°±16.02° on the high and low sides of pelvis, respectively, and the difference was statistically significant ( t=3.990 , P<0.001). SA was 30.14°±21.93° on the anterior side of the pelvis and 51.00°±15.96° on the posterior side, respectively, with statistical significance ( t=4.027, P<0.001). TA was 43.67°±12.86° on the high side of pelvic tilt and 31.95°±13.80° on the low side, with statistical significance ( t=2.834, P=0.009). TA was 42.56°±12.52° on the anterior side of the pelvis and 33.05°±14.94° on the posterior side, respectively, and the differences were statistically significant ( t=2.192, P=0.037). ML was 97.12±12.44 mm and 92.28±11.04 mm on the high and low side of pelvis, and there was no significant difference ( t=0.963 , P=0.060). ML was 97.72±12.41 mm on the anterior sides of the pelvis and 91.68±10.57 mm on the posterior side, and the difference was statistically significant ( t=2.556 , P=0.017). SA tended to be smaller on the high side of pelvic tilt ( r=0.474, P<0.01) and TA tended to be higher on the anterior side of pelvis ( r=-0.419, P<0.01) . Only 2 screws (3.6%) showed screw breaches after surgery, with no clinically notable neurovascular or visceral complications. Conclusion:In patients of neuromuscular scoliosis with severe pelvic obliquity, the virtual S 2AI screw trajectory can be found in 3D CT reconstruction of the pelvis. But the parameters are very discrete at SA and TA. In these patients, the O-arm 3D CT navigation can be used to make sure the direction and length of the S 2AI screw, greatly improving the accuracy of screw placement and effectively descending the ratio of poor screw.

A comparative study of orthopaedic robot and O-arm navigation to pelvic fractures / 中华骨科杂志

Objective:By comparing the clinical effect of minimally invasive hollow screw internal fixation Assisted by orthopedic robot (TiRobot) and O-arm navigation in the treatment of pelvic fractures, and practicability and security of both treatments were evaluated.Methods:Retrospective analysis of data of 42 cases of Tile C type pelvic fractures was employed during June 2017 to June 2020. Among them, 32 cases, twenty-four men, eight women, aged 34±6.2 years (range 24-68 years), were treated with percutaneous screw fixation guided by O-arm X wire instrument. According to Tile classification, there were 3 cases of C1.1 type, 8 cases of C1.2 type and 21case of C1.3 type. According to the Denis classification of sacral fractures, 17 cases were in zone I, and 8 cases in zone II. Ten patients, eight males and two females, aged 36±5.2 years (range 19-62 years) were treated by percutaneous screw fixation assisted by orthopedic robot. According to Tile classification, there were 1 case of C1.1 type, 2 cases of C1.2 type and 7 cases of C1.3 type. According to the Denis classification of sacral fractures, there were 5cases in zone I, 2 cases in zone II. For those who got obviously displaced pelvic fractures, Starr frames were used and then internal fixation was used to fix pelvic anterior ring and posterior ring injury respectively. Based on the times of needle adjustments, intraoperative fluoroscopy time, good screw position and incidence of complications two groups were statistically analysed. Matta score was employed to evaluate the quality of fracture reduction, while the Majeed score was employed to evaluate the clinical efficacy. Through the two groups of cases guide needle adjustment times, intraoperative fluoroscopy time, screw position excellent and good rate and the incidence of complications, which were statistically analyzed.Results:All screw positions were confirmed by CT scan after operation. The average time required for each screw placement of the O-arm group was 7.36±2.63 s, of the robot group was 6.80±3.20 s, so difference was not statistically significant ( P<0.05). An average of screw adjustments per one screw was 1.56±0.02 times by O-arm, and by the robot group was 0.34±0.06 times, so differences between the two groups were statistically significant ( P>0.05). The average operating time of O-arm group was 53.86±15.06 min, while the robot group was 52.52±15.14 min, so differences between the two groups were not statistically significant ( P>0.05). Position distribution of screw placement in two groups, all screws in O-arm group of position evaluations were excellent, excellent rate was 100%, all screw position evaluations by robot were excellent, excellent rate was 100%, so difference in screw distribution between the two groups was not statistically significant ( P>0.05). All cases were followed up for 6-12 months. Fracture healing time: 34.6±8.6 weeks for O-arm group, 33.4±9.4 weeks for robot group. Comparison between the two groups was not statistically significant ( P>0.05). Majeed score of O-arm group was 55-87, including Excellence of 17 cases, goodness of 9, fairness of 6. The rate of excellence and goodness was 81.2%, while robot group was 76-95, and that were excellent 7 cases,1 good, and the excellent and good rate was 80%, there was no significant difference between Matta and Majeed score between the two groups ( P>0.05). The incidence of complications between the two groups were no statistically significant ( P>0.05). Conclusion:Orthopedic robot system and O-arm navigation system assisted by percutaneous hollow screw fixation treatment of pelvic anterior and posterior ring injury, which are accurate, safe, minimally invasive, can reduce radiation damage to patients and surgeons. The efficacy were satisfactory. Both treatments are ideal for minimally invasive treatment of pelvic fractures, and the orthopedic robot have advantages of being programmed, standardized, stable and it’s learning curve is shorter.

Computer-assisted pelvic osteotomy and 3D printing guide plate for developmental dislocation of hip surgery / 中华骨科杂志

Objective:To explore the scheme of accurate pelvic osteotomy parameters and to analyze the feasibility and efficacy of 3D printing navigation plate in developmental dysplasia of the hip surgery.Methods:From January 2015 to December 2017, a total of 18 children with DDH underwent computer-assisted Salter pelvic osteotomy (computer-assisted osteotomy group) and 25 children with DDH who underwent conventional Salter pelvic osteotomy (conventional osteotomy group) were selected for retrospective analysis. There were 11 males and 32 females with an average age of 3.2±2.5 (range 1-11) years. According to International Hip Dysplasia Institute (IHDI) classification, there were 20 cases of type 1, 9 of type 2, 12 of type 3 and 2 of type 4. All patients were unilateral dislocation, including 18 cases on the left and 25 on the right. All children underwent pelvic CT examination before operation. Further, the proximal femur was surgically corrected during the operation. According to the acetabular rotation angle (ATA) and bony acetabular index (BAI), the computer-assisted osteotomy group simulated the operation with Mimics software made 3D printing navigation plate through which an accurate osteotomy scheme was developed. The two groups were compared in operative duration, intraoperative blood loss, Japanese Orthopaedic Association (JOA) hip joint score. Acetabular index (AI), central edge (CE) angle, and acetabulum head index (AHI) were compared between the two groups by using postoperative X-ray. The acetabular tilt angle (ATA) changes before and after operation in the computer-assisted osteotomy group were compared through 3D CT.Results:The follow-up duration was 2.3±0.2 (2.0 to 2.5) years in the computer-assisted osteotomy group and 2.8±0.15 (2.5 to 3.0) years in the conventional osteotomy group. The operative duration in the computer-assisted osteotomy group was 127±20.6 min, which was significantly longer ( t=4.657, P<0.001) than that in the conventional osteotomy group (103±13.2 min). Intraoperative bleeding was 157±17.5 ml in the computer-assisted osteotomy group and 151±15.3 ml in the conventional osteotomy group without significant difference between the two groups ( t=1.195, P=0.239). At 2 years after surgery, the JOA score of the hip joint in the computer-assisted osteotomy group (86.7±8.5 points) was like that (84.8±10.0 points) in the conventional osteotomy group ( t=0.628, P=0.533). At the last follow-up, the CE angle in the computer-assisted osteotomy group (36.8°±5.2°) was significantly larger than that (31.8°±4.4°) in the conventional osteotomy group ( t=3.414, P<0.001). There was statistically significant difference in term of AHI between the computer-assisted osteotomy group (85.8%±6.6%) and the conventional osteotomy group (80.4%±8.3%, t=2.284, P=0.028). AI was 23.5°±5.5° in the computer-assisted osteotomy group and 25.2°±4.2° in the conventional osteotomy group without significant difference ( t=-1.150, P=0.257). The ATA of the affected side was 12.3°±1.4° in the computer-assisted osteotomy group which was similar ( t=0.614, P=0.547) to that of the healthy side (11.8°±2.8°). Conclusion:Based on specific anatomical parameters, computer-assisted preoperative planning can not only directly simulate the process of osteotomy, but also produce individualized 3D printed guide plates. Compared with conventional Salter pelvic osteotomy, computer-assisted osteotomy can achieve accurate radiographic correction of the hip joint in children with DDH, resulting in a better matching relationship between the femoral head and acetabulum.

Three dimensional nephrometry system for partial nephrectomy: Our initial exploration / 北京大学学报(医学版)

OBJECTIVE@#To construct a preoperative evaluation system for partial nephrectomy using CT three-dimensional visualization technology and to explore its practical value.@*METHODS@#The clinical data of the patients who underwent partial nephrectomy for renal tumors in Department of Urology, Peking University First Hospital were collected retrospectively. At the same time, the homogenized standard data of patients who underwent partial nephrectomy for renal tumors were collected in 16 clinical centers in China. The CT three-dimensional visualization system was applied (IPS system, Yorktal) to evaluate tumor anatomy, blood supply, perirenal fat and other information. The parameters were summarized to build a three-dimensional nephrometry system, on the basis of which virtual surgery design and intraoperative navigation were completed.@*RESULTS@#A three-dimensional visualization image was established based on the enhanced CT urography. The nephrometry system included the longest diameter and volume of the tumor, proportion volume of tumor invading the parenchyma, maximum depth of the tumor invading the parenchyma, contact surface area, flatness of the tumor surface, renal segment where the tumor was located, vascular variation, and perirenal fat. The average two-dimensional diameter of the tumor was (2.78±1.43) cm, the average three-dimensional maximum diameter was (3.09±1.35) cm, and the average postoperative pathological size was (3.01±1.38) cm. The maximum tumor diameter in the three-dimensional image was significantly related to the prolonged renal artery clamping time and intra-operative blood loss (r=0.502, P=0.020; r=0.403, P=0.046). The three-dimensional and pathological tumor volume were (25.7±48.4) cm3 and (33.0±36.4) cm3, respectively (P=0.229). The tumor volume was significantly related to the intraoperative blood loss (r=0.660, P < 0.001). The proportion volume of the tumor invading into renal parenchyma was significantly related to the prolongation of renal artery clamping and the occurrence of postoperative complications (r=0.410, P=0.041; r=0.587, P=0.005). The tumor contact surface area and the presence of vascular variation did not show correlation with the perioperative data and postoperative complications. While the preoperative evaluation was completed, the reconstructed three-dimensional image could be zoomed, rotated, combined display, color adjustment, transparency, and simulated cutting on the Touch Viewer system. The process generally consisted of showing or hiding the tissue, adjusting the transparency of the interested area, rotating and zooming the image to match the position of the surgical patient. Together, these functions met the requirements of preoperative virtual surgery plan and intraoperative auxiliary navigation.@*CONCLUSION@#Three-dimensional images can provide a more intuitive anatomical structure. The CT three-dimensional visua-lization system clearly displays tumor anatomical parameters, blood supply and perirenal fat. The three-dimensional nephrometry system for renal tumors can help predict the difficulty of partial nephrectomy and perioperative complications. Importing the reconstructed three-dimensional visualization image into the specified program or robot operating system can complete virtual surgery and intraoperative navigation, helping the surgeon to better grasp the surgical process. The indexes included in the nephrometry system and the score weights of each index need to be confirmed and perfected by multi-center study with large samples.

Application of 3D printing guide plate in total hip arthroplasty for developmental dysplasia of the hip / 中国骨伤

OBJECTIVE@#To explore the value of 3D-printed navigation template using in total hip arthroplasty(THA)for developmental dysplasia of the hip (DDH).@*METHODS@#Twenty five patients with DDH underwent total hip arthroplasty from February 2016 to May 2018 were analyzed retrospectively, including 4 males and 21 females, aged from 40 to 75 years old. Among them, 5 cases were Crowe typeⅡ, 14 cases were Crowe type Ⅲ and 6 cases were Crowe type Ⅳ. Twelve cases of them underwent THA with the 3D printing navigation plate, another 13 cases underwent the same operation but without the aid of navigation templates. All patients were treated by the same operators. The operating time, intra- and post-operative hemorrhage and Harris Hip Score(HHS) at six months postoperativelywere compared, anteversion angle, abduction angle and the distance from rotation center to the ischial tuberosity connection between ipsilateral and contralateral sides were also compared.@*RESULTS@#All of the patients were followed up for 12 to 26 months. The operation time, intra- and post-operative hemorrhage and Harris score in the 3D printing group were better than those in the conventional hip replacement group(@*CONCLUSION@#The 3D-printed operation navigation template technique is an individualized, accurate and promisingtechnique for THA with DDH.