Long-term outcomes of lateral femoral notch after early anterior cruciate ligament reconstruction / 中国骨伤

OBJECTIVE@#To investigate the outcome of lateral femoral notch (LFN) after early anterior cruciate ligament (ACL) reconstruction and evaluate the recovery of knee joint function after the operation.@*METHODS@#The clinical data of 32 patients who underwent early ACL reconstruction from December 2015 to December 2019 were retrospectively analyzed. The study included 18 males and 14 females, aged 16 to 54 years old, with an average age of (25.39±2.82) years. The body mass index (BMI) of the patients ranged from 20 to 30 kg/cm2, with an average of (26.15±3.09) kg/cm2. Among them, 6 cases were caused by traffic accidents, 19 by exercise, and 7 by the crush of heavy objects. MRI of all patients showed LFN depth was more than 1.5 mm after injury, and no intervention for LFN was performed during surgery. Preoperative and postoperative depth, area, and volume of LFN defects were observed by MRI data. International Cartilage Repair Society (ICRS) score, Lysholm score, Tegner activity levels, and knee injury and osteoarthritis outcome score (KOOS) were analyzed before and after the operation.@*RESULTS@#All patients were followed up from 2 to 6 years with an average of (3.28±1.12) years. There was no significant difference in the defect depth of LFN from (2.31±0.67) mm before the operation to (2.53±0.50) mm at follow-up (P=0.136). The defect area of LFN was decreased from (207.55±81.01)mm2 to (171.36±52.69)mm2 (P=0.038), and the defect volume of LFN was decreased from (426.32±176.54) mm3 to (340.86±151.54)mm3 (P=0.042). The ICRS score increased from (1.51±0.34) to (2.92±0.33) (P<0.001), the Lysholm score increased from (35.37±10.54) to (94.46±8.45) (P<0.001), and the Tegner motor score increased from (3.45±0.94) to (7.56±1.28), which was significantly higher than that of the preoperative data (P<0.001). The KOOS score of the final follow-up was 90.42±16.35.@*CONCLUSION@#With the increase of recovery time after anterior cruciate ligament reconstruction, the defect area and volume of LFN decreased gradually, but the defect depth remained unchanged. The knee joint function of the patients significantly improved. The cartilage of the LFN defect improved, but the repair effect was not good.

Three-dimensional kinematic analysis of knee joint after anterior cruciate ligament reconstruction with personalized femoral positioner based on apex of deep cartilage / 中国修复重建外科杂志

OBJECTIVE@#To investigate the changes of knee joint kinematics after anterior cruciate ligament (ACL) reconstruction assisted by personalized femoral positioner based on the apex of deep cartilage (ADC).@*METHODS@#Between January 2021 and January 2022, a total of 40 patients with initial ACL rupture who met the selection criteria were randomly divided into the study group (using the personalized femoral positioner based on ADC design to assist ACL reconstruction) and the control group (not using the personalized femoral positioner to assist ACL reconstruction), with 20 patients in each group. Another 20 volunteers with normal knee were collected as a healthy group. There was no significant difference in gender, age, body mass index, and affected side between groups ( P>0.05). Gait analysis was performed at 3, 6, and 12 months after operation using Opti _ Knee three-dimensional knee joint motion measurement and analysis system, and the 6 degrees of freedom (flexion and extension angle, varus and valgus angle, internal and external rotation angle, anteroposterior displacement, superior and inferior displacement, internal and external displacement) and motion cycle (maximum step length, minimum step length, and step frequency) of the knee joint were recorded. The patients' data was compared to the data of healthy group.@*RESULTS@#In the healthy group, the flexion and extension angle was (57.80±3.45)°, the varus and valgus angle was (10.54±1.05)°, the internal and external rotation angle was (13.02±1.66)°, and the anteroposterior displacement was (1.44±0.39) cm, the superior and inferior displacement was (0.86±0.20) cm, and the internal and external displacement was (1.38±0.39) cm. The maximum step length was (51.24±1.29) cm, the minimum step length was (45.69±2.28) cm, and the step frequency was (12.45±0.47) step/minute. Compared with the healthy group, the flexion and extension angles and internal and external rotation angles of the patients in the study group and the control group decreased at 3 months after operation, and the flexion and extension angles of the patients in the control group decreased at 6 months after operation, and the differences were significant ( P<0.05); there was no significant difference in the other time points and other indicators when compared with healthy group ( P>0.05). In the study group, the flexion and extension angles and internal and external rotation angles at 6 and 12 months after operation were significantly greater than those at 3 months after operation ( P<0.05), while there was no significant difference in the other indicators at other time points ( P>0.05). There was a significant difference in flexion and extension angle between the study group and the control group at 6 months after operation ( P<0.05), but there was no significant difference of the indicators between the two groups at other time points ( P>0.05).@*CONCLUSION@#Compared with conventional surgery, ACL reconstruction assisted by personalized femoral positioner based on ADC design can help patients achieve more satisfactory early postoperative kinematic results, and three-dimensional kinematic analysis can more objectively and dynamically evaluate the postoperative recovery of knee joint.

Comparison of filling ratio, alignment, and stability between ABG Ⅱ short-stem and Corail long-stem in total hip arthroplasty for Dorr type C femur / 中国修复重建外科杂志

OBJECTIVE@#Using the mono-energy reconstruction images and X-ray films to investigate whether the ABG Ⅱ short-stem could improve the filling ratio, stability, and alignment in the Dorr type C femur, compared with the Corail long-stem.@*METHODS@#Among patients who were with Dorr type C femurs and treated with total hip arthroplasty between January 2006 and March 2012, 20 patients with a Corail long-stem (Corail group) and 20 patients with an ABG Ⅱ short-stem (ABG Ⅱ group) were randomly selected. The differences in gender, age, body mass index, and preoperative diagnoses between the two groups were not significant ( P>0.05). The ABG Ⅱ group was with a mean follow-up of 142 months (range, 102-156 months), and the Corail group was with a mean follow-up of 107 months (range, 91-127 months). There was no significant difference in the Harris score and subjective satisfaction score between the two groups at last follow-up ( P>0.05). At last follow-up, dual-energy CT scans with mono-energy image reconstruction were used to calculate the prosthetic filling ratio and to measure the alignment of the prosthesis in the coronal and sagittal positions. Stability assessment was performed based on X-ray films, and the subsidence distance was measured using EBRA-FCA software.@*RESULTS@#X-ray film observation showed that the prostheses in the two groups were stable and no signs of loosening was found. The incidence of pedestal sign was significantly lower in the ABGⅡ group than in the Corail group ( P<0.05), and the incidence of heterotopic ossification was significantly higher in the ABGⅡ group than in the Corail group ( P<0.05). The subsidence distance of femoral stem in ABG Ⅱ group was significantly greater than that in Corail group ( P<0.05), and the subsidence speed of femoral stem in ABG Ⅱ group was also greater than that in Corail group, but the difference was not significant ( P>0.05). The overall prosthesis filling ratio was significantly higher in the ABG Ⅱ group than in the Corail group ( P<0.05), while the coronal filling ratio at the lesser trochanter, 2 cm below the lesser trochanter, and 7 cm below the lesser trochanter were not significant ( P>0.05). The results of prosthesis alignment showed that there was no significant difference in the sagittal alignment error value and the incidence of coronal and sagittal alignment error >3° between the two groups ( P>0.05), while the coronal alignment error value in the ABG Ⅱ group was significantly greater than that in the Corail group ( P<0.05).@*CONCLUSION@#Although the ABG Ⅱ short-stem avoids the distal-proximal mismatch of the Corail long-stem in the Dorr type C femur and thus achieves a higher filling ratio, it does not appear to achieve better alignment or stability.

Clinical effects of island posterior femoral composite tissue flaps in the repair of sinus cavity pressure ulcers in the areas of ischial tuberosity and greater trochanter / 中华烧伤杂志

Objective: To explore the clinical effects of island posterior femoral composite tissue flaps in the repair of sinus cavity pressure ulcers in the areas of ischial tuberosity and greater trochanter. Methods: The retrospective observational study was conducted. From December 2018 to December 2021, 23 patients with sinus cavity pressure ulcers in the areas of ischial tuberosity and greater trochanter who met the inclusion criteria were admitted to Ganzhou People's Hospital, including 16 males and 7 females, aged 45 to 86 years. The size of pressure ulcers in ischial tuberosity ranged from 1.5 cm×1.0 cm to 8.0 cm×5.0 cm, and the size of pressure ulcers in greater trochanter ranged from 4.0 cm×3.0 cm to 20.0 cm×10.0 cm before debridement. After treatment of underlying diseases, debridement and vacuum sealing drainage for 5 to 14 days were performed. All the wounds were repaired by island posterior femoral composite tissue flaps, with area of 4.5 cm×3.0 cm-24.0 cm×12.0 cm, pedicle width of 3-5 cm, pedicle length of 5-8 cm, and rotation radius of 30-40 cm. Most of the donor site wounds were sutured directly, and only 4 donor site wounds were repaired by intermediate thickness skin graft from the contralateral thigh. The survival of composite tissue flaps, wound healing of the donor and recipient sites and the complications were observed. The recurrence of pressure ulcers, and the appearance and texture of flaps were observed during follow-up. Results: A total of 32 wounds in 23 patients were repaired by island posterior femoral composite tissue flaps (including 3 fascio subcutaneous flaps, 24 fascial flaps+fascio subcutaneous flaps, 2 fascial flaps+fascial dermal flaps, 2 fascial flaps+fascio subcutaneous flaps+femoral biceps flaps, and one fascial flap+fascio subcutaneous flap+gracilis muscle flap). Among them, 31 composite tissue flaps survived well, and a small portion of necrosis occurred in one fascial flap+fascio subcutaneous flap post surgery. The survival rate of composite tissue flap post surgery was 96.9% (31/32). Twenty-nine wounds in the recipient sites were healed, and 2 wounds were torn at the flap pedicle due to improper postural changes, and healed one week after bedside debridement. One wound was partially necrotic due to the flap bruising, and healed 10 days after re-debridement. Thirty-one wounds in the donor sites (including 4 skin graft areas) were healed, and one wound in the donor site was torn due to improper handling at discharge, and healed 15 days after re-debridement and suture. The complication rate was 12.5% (4/32), mainly the incision dehiscence of the flap pedicle and the donor sites (3 wounds), followed by venous congestion at the distal end of flap (one wound). During the follow-up of 3 to 24 months, the pressure ulcers did not recur and the flaps had good appearance and soft texture. Conclusions: The island posterior femoral composite tissue flaps has good blood circulation, large rotation radius, and sufficient tissue volume. It has a high survival rate, good wound healing, low skin grafting rate in the donor site, few postoperative complications, and good long-term effect in the repair of sinus cavity pressure ulcers in the areas of ischial tuberosity and greater trochanter.

Imaging measurement and analysis of related indexes of variation of femoral head rotation center / 中国骨伤

OBJECTIVE@#To provide guidance for hip replacement by analyzing the variation of femoral head rotation center in different hip diseases.@*METHODS@#A total of 5 459 patients were collected from March 2016 to June 2021, who took positive and proportional plain films of both hips for various reasons. The relative position between the rotation center of the femoral head and the apex of the greater trochanter was measured. The positive variation is more than 2 mm above the top of the great trochanter, and the negative variation is more than 2 mm below the top of the great trochanter. A total of 831 patients with variation of femoral head rotation center were collected and were divided into 4 groups according to different diseases, and the variation was counted respectively. There were 15 cases in the normal group involving 10 cases of positive variation and 5 cases of negative variation. There were 145 cases of avascular necrosis of femoral head involving 25 cases of positive variation and 120 cases of negative variation. There were 346 cases of congenital hip dysplasia involving 225 cases of positive variation(including 25 cases of typeⅠ, 70 cases of type Ⅱ, 115 cases of type Ⅲ and 15 cases of type Ⅳ), and 121 cases of negative variation(including 50 cases of crowe typeⅠ, 60 cases of typeⅡ, 10 cases of type Ⅲ and 1 case of type Ⅳ). There were 325 cases of hip osteoarthritis group involving 45 cases of positive variation and 280 cases of negative variation.@*RESULTS@#There was significant difference in variation of femoral head rotation center among the four groups(P<0.05). There was significant difference in variation of femoral head rotation center among different types of congenital hip dysplasia(P<0.05). There were significant differences in cervical trunk angle and eccentricity among different variations of femoral head rotation center(P<0.05).@*CONCLUSION@#The variation of femoral head rotation center is related to cervical trunk angle and eccentricity. The variation of femoral head rotation center is an important factor in hip diseases. The variation of femoral head rotation center is different in different hip diseases. Avascular necrosis of the femoral head and osteoarthritis of the hip were mostly negative variations. With the aggravation of congenital hip dysplasia, the variation of femoral head rotation center gradually changed from negative variation to positive variation.The variation of femoral head rotation center should be paid attention to in the preoperative planning of hip arthroplasty. It is of great significance to select the appropriate prosthesis and place the prosthesis accurately.

Medición radiológica del extremo proximal del fémur / Radiological measurement of the femoral proximal end

El objetivo de este trabajo es determinar las mediciones radiológicas del extremo proximal del fémur en pacientes adultos cuyos casos fueron presentados en las discusiones clínico-radiológicas del servicio de Traumatología y Ortopedia del Hospital Central de San Cristóbal entre 2015 y 2021. Se realizó un estudio prospectivo, descriptivo, transversal, que incluyó los estudios radiológicos de cadera sana en proyección anteroposterior de pelvis centrada en pubis con rotación interna de 15 %, de 126 pacientes entre 20 y 95 años. Se midieron: ángulo cervicodiafisario, lateralización femoral, longitud y ancho del cuello femoral y diámetro de la circunferencia cefálica, mediante el sotfware MicroDicom DICOM 4.0.0. La media de ángulo cervicodiafisario fue 130,8 ± 4,5 grados, en 57 individuos (45,2 %) estuvo entre 127,4 y 133,3 grados (p = 0,001); la circunferencia cefálica media fue 42,0 ± 2,4 mm, en 60 personas (47,6 %) estuvo entre 40,2 y 45,7 mm (p = 0,001); la longitud cervical media fue 78,6 ± 16,4 mm, en 54 individuos (42,9 %) estuvo entre 69,4 y 92 mm (p = 0,001); el ancho cervical medio fue 75,9 ± 12,1 mm, en 64 casos, (50,8 %) estuvo entre 62,9 y 78,7 mm (p = 0,001). En 60 individuos (47,6 %) la lateralización del fémur estuvo entre 92,6 - 117,7 mm. Las medidas son independientes del sexo; a medida que aumenta la edad, el ángulo cervicodiafisario es menor (p= 0,021). Se realizaron tablas percentiladas de las medidas radiológicas del extremo proximal del fémur, según edad y sexo, que pueden servir de referencia en pacientes futuros(AU)

The objective of this work is to determine the radiological measurements of the proximal end of the femur in adult patients whose cases were presented in the clinical-radiological discussions of the Traumatology and Orthopedics service of the Central Hospital of San Cristóbal between 2015 and 2021. A prospective study was carried out, descriptive, crosssectional, which included radiological studies of a healthy hip in anteroposterior projection of the pelvis centered on the pubis with internal rotation of 15%, of 126 patients between 20 and 95 years of age. The following were measured: cervicodiaphyseal angle, femoral lateralization, length and width of the femoral neck, and diameter of the head circumference, using the MicroDicom DICOM 4.0.0 software. The mean neck-diaphyseal angle was 130.8 ± 4.5 degrees, in 57 individuals (45.2%) it was between 127.4 and 133.3 degrees (p = 0.001); the mean head circumference was 42.0 ± 2.4 mm, in 60 people (47.6%) it was between 40.2 and 45.7 mm (p = 0.001); the mean cervical length was 78.6 ± 16.4 mm, in 54 individuals (42.9 %) it was between 69.4 and 92 mm (p = 0.001); the mean cervical width was 75.9 ± 12.1 mm, in 64 cases (50.8%) it was between 62.9 and 78.7 mm (p= 0.001). In 60 individuals (47.6%), the lateralization of the femur was between 92.6 - 117.7 mm. The measurements are independent of sex; as age increases, the cervical shaft angle is less (p= 0.021). Percentage tables of the radiological measurements of the proximal end of the femur were made, according to age and sex, which can serve as a reference in future patients(AU)

Conceptos actuales en osteotomías en doble nivel alrededor de la rodilla / Current concepts in double-level osteotomies around the knee

Con la osteotomía en un solo nivel, se puede lograr la corrección del eje de la extremidad en pacientes con deformidades combinadas femoral y tibial, pero de forma simultánea generará una alteración patológica de oblicuidad de la interlínea articular, lo que conducirá a elongación ligamentaria, inestabilidad, degeneración condral y, en última instancia, comprometerá su sobrevida y los resultados funcionales. En virtud del análisis de la literatura más reciente, podemos concluir que existe un número significativo de pacientes que requieren de un procedimiento combinado para lograr un objetivo biomecánico óptimo. La finalidad de una osteotomía en doble nivel alrededor de la rodilla consiste en restablecer la anatomía normal, descargar el compartimiento afectado, normalizar los ángulos mecánicos y la orientación de la interlínea articular. Los ejes fisiológicos pueden restablecerse a través de un análisis preoperatorio exhaustivo, respetando principios biomecánicos y fijación estable con placas bloqueadas. Es un procedimiento demandante y con indicaciones en evolución, que progresivamente se ha instaurado como una alternativa de tratamiento justificada en estudios clínicos y biomecánicos para el manejo de deformidades severas alrededor de la rodilla.

With single-level osteotomy, correction of the limb axis in patients with combined femoral and tibial deformities can be achieved. This correction, however, will generate a pathological alteration in the joint line oblicuity, leading to ligament elongation, instability, joint degeneration and, ultimately, it will compromise the longevity and functional results of the correction. By analyzing the most recent literature, we can conclude that there is a significant number of patients who require a combined procedure to achieve an optimal biomechanical goal. The purpose of a double-level osteotomy around the knee is to restore normal anatomy, unload the affected compartment, normalize the mechanical angles and the orientation of the joint line. Physiological axes can be reestablished by means of a thorough preoperative analysis, observing the biomechanical principles and stable fixation with locked plates. It is a demanding procedure with increasing indications, which has progressively been established in clinical and biomechanical studies as a justified treatment alternative for the management of severe deformities around the knee.

Application of extended trochanter osteotomy wire fixation combined with autologous bone graft in revision of total hip arthroplasty / 中国骨伤

OBJECTIVE@#To investigate the clinical effect of using lengthened trochanteric osteotomy wire fixation combined with autologous bone graft in patients undergoing revision total hip arthroplasty.@*METHODS@#From December 2010 to December 2018, 18 patients underwent revision of total hip arthroplasty with extended trochanteric osteotomy wire fixation and autogenous bone graft, including 8 males and 10 females with an average age of (78.89±3.32) years old ranging from 68 to 82 years. The time from the initial replacement to the revision was 9 to 22 (16.33±2.93) years. The patients were followed up regularly after operation. The healing time of osteotomy, the time of full weight-bearing activity, Harris score of hip joint and complications were recorded.@*RESULTS@#All 18 patients were followed up for 16 to 38 months with an average of (25.78±6.65) months. The incision length was 16 to 21 cm with an average of (18.89±1.32) cm; the operation time was 105 to 128 min with an average of (115.44±6.59) min, the bleeding volume was 240 to 285 ml with an average of (267.44±13.77) ml. The healing time of osteotomy was 12 to 18 weeks with an average of (15.61±1.75) weeks. Harris score of hip joint was (47.11±5.04) before operation, (76.39±3.85) during full weight-bearing activities, and (82.22±2.76) at the final follow-up(P<0.05). During the follow-up period, there were no complications such as limb shortening, infection, poor incision healing, prosthesis loosening and sinking, and periprosthetic fracture.@*CONCLUSION@#In revision total hip arthroplasty, the use of extended trochanteric osteotomy wire fixation combined with autologous bone graft can achieve satisfactory clinical results, but the surgeon needs to make a systematic plan for the pre-revision, intraoperative and postoperative recovery.

Rotational alignment of the tibial component in total knee arthroplasty:a narrative review / 中华外科杂志

Component malrotation is one of the major causes of failure in total knee arthroplasty.Based on previous researches,Insall line has excessive external rotation tendency.Although Akagi line is the most recognized anatomical axis at present,it still has a certain tendency of internal rotation.The tibial posterior condylar axis is not suitable for symmetrical component and yet the Curve-on-Curve technique is not suitable for anatomic component.In addition,reference to any fixed anatomical markers cannot ensure the rotation consistency of tibiofemoral component in extension position.Although range of motion technique is beneficial to tibiofemoral rotation synchronization,its clinical effect seems to be unstable.Nevertheless,Patients can obtain good postoperative results with all major techniques.Before the recognized "gold standard" is defined,orthopedic surgeons can determine the rotation alignment of tibial component according to their most accustomed surgical method.With a deeper understanding of knee anatomy,biomechanics and kinematics,digital assistive technology may be expected to become a breakthrough in the tibial rotational alignment.

Comparison of radiographic and tomographic evaluations for measurement of the Canal Flare Index in dogs / [Comparação entre avaliação radiográfica e tomográfica para mensuração do Canal Flare Index em cães]

The outcome of total hip arthroplasty (THA) in dogs is directly related to surgical planning. Templating of radiographs prior to THA should help the surgeon anticipate prosthesis size and femoral shape allowing canal fill of the proximal metaphysis by the implant ensuring primary stable fixation. The canal flare index (CFI) obtained from radiograph has been used as a measure of risk of complications for the technique in human beings and dogs. However, standard radiographs only provide limited data for the selection of cementless prostheses and the assessment of their fit within the femoral canal, due to factors like radiographic magnification and femoral rotation. Therefore, three-dimensional evaluation based on computed tomography (CT) may be a better tool for CFI measurement. The aim of this study was to compare anatomical measurement with CFI values obtained from craniocaudal radiography and CT. Craniocaudal radiographs using a horizontal radiographic beam (CR), CT, and anatomical macroscopic measurements (A) were obtained from 45 femurs from 23 canine cadavers. The differences between the values of CFI obtained from radiograph (CFI-R), computed tomography on transverse (CFI- TT) and longitudinal axis (CFI-TL) compared to the CFI obtained from macroscopic measurements - gold standard - (CFI-A), and 95% limits of agreement (LOA) between the values, were evaluated by the Bland-Altman method. Dimensions obtained from CT techniques had a greatest mean difference from anatomical and CFI values were also different (P=0.032). Under the experimental conditions, the craniocaudal radiograph, provided the most accurate measurement of the CFI (mean difference: 0.087 ± 0.42).(AU)

O resultado da artroplastia total do quadril (ATQ) em cães está diretamente relacionado ao planejamento cirúrgico. O templating radiográfico pré-operatório da ATQ deve ajudar o cirurgião a prever o tamanho da prótese e o formato do fêmur, o que permitirá um preenchimento ideal da metáfise proximal pelo implante, garantindo, assim, fixação primária estável. O índice de alargamento do canal (Canal Flare Index - CFI) obtido em radiografias tem sido utilizado como fator de risco de complicações para a técnica em humanos e cães. No entanto, as radiografias podem fornecer apenas dados limitados para a seleção de próteses não cimentadas e a avaliação do seu encaixe no canal femoral, devido a fatores como ampliação radiográfica e rotação femoral. Portanto, a avaliação tridimensional baseada na tomografia computadorizada (TC) pode ser uma ferramenta vantajosa para a mensuração do CFI. O objetivo deste estudo foi comparar a medida anatômica com os valores de CFI obtidos na radiografia craniocaudal e na TC. Radiografias craniocaudais utilizando feixe radiográfico horizontal (CR), tomografia computadorizada e medidas macroscópicas anatômicas (A) foram obtidas de 45 fêmures de 23 cadáveres caninos. As diferenças entre os valores de CFI obtidos na radiografia (CFI-R), na tomografia computadorizada no eixo transversal (CFI-TT) e no eixo longitudinal (CFI-TL), em comparação com os valores de CFI obtidos nas medições macroscópicas - padrão-ouro - (CFI-A) e os limites de concordância de 95% (LOA) entre os valores, foram avaliadas pelo método de Bland-Altman. As dimensões obtidas pelas técnicas de TC apresentaram maior diferença média dos valores anatômicos, e as do CFI também foram diferentes (P=0,032). Nas condições experimentais, a radiografia craniocaudal forneceu a medida mais precisa do CFI (diferença média: 0,087 ± 0,42) para representar o padrão-ouro deste estudo.(AU)

Biomechanical evaluation of a new femoral stem design for total hip replacement in a canine model

ABSTRACT Purpose To evaluate the biomechanical properties of a novel total hip replacement femoral stem. Methods Eight pairs of femurs from dog cadavers were used. The femurs were separated into different groups. A novel femoral stem with a convex proximal portion (Stem B) was biomechanically evaluated and compared to awell-known veterinary collared stem (Stem A). Femoral stems were inserted into the contralateral femurs from the same dog, forming 16 constructs. A flexo-compression load was applied on the axial axis of each sample. Maximum strength, deflection, stiffness, and energy absorption were analysed. Results Group B constructs showed significantly higher values (p ? 0.05) for the variables, except stiffness. The mean maximum strength was 1,347 ± 357 N for Group A and 1,805 ± 123 N for Group B (p ? 0.0069). The mean deflection was5.54 ± 2.63 mm for Group A and 10.03 ± 3.99 mm for Group B (p ? 0.0056). For the energy variable, the force was 6,203 ± 3,488 N/mm for Group A and 12,885 ± 5,056 N/mm for Group B (p ? 0.0054). Stem B had greater maximum strength, deflection, and energy. Conclusions The new stem was effective in neutralizing the impact of axial flexion-compression stresses during biomechanical tests in cadaveric models.

Lengths of the fixed loop and the adjustable loop in the coarse bone tunnel were compared to influence the widening of the femoral bone tunnel and the function of the knee joint / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the effects of two different femoral cortical suspension devices (fixation loop and adjustable loop) on tunnel widening and knee function in patients following anterior cruciate ligament reconstruction for 12 months.@*METHODS@#A total of 60 patients who had undergone anterior cruciate ligament reconstruction were included in this study. According to the length of the loop(n)[n= total length of loop-(total length of femoral tunnel-total length of coarse tunnel)] in the rough bone tunnel, the patients were divided into A (adjustable loop was 0 mm in the coarse bone tunnel), B (fixation loop was greater than 0 mm and less than or equal to 10 mm in the coarse bone tunnel) and C (fixation loop was greater than 10 mm in the coarse bone tunnel) groups, of which 11 cases were in group A, 27 cases in group B and 22 cases in group C. In the three-dimensional reconstruction of the knee joint with multi-slice spiral CT, the widening of the bone tunnel in the three groups was compared. At the same time, IKDC, Lysholm and Tegner scores of the patients in the three groups were compared.@*RESULTS@#There were differences in the widening degree of the femoral canal among groups A, B and C, and the median difference of the widening degree of the femoral tunnel 12 months and immediately after the surgery was A < B < C. The difference of femoral canal widening in group A was significantly different from that in groups B and C (P < 0.05).According to the linear regression the relationship between the difference of the width of the femoral canal and the change of the length (n) of the loop in the coarse canal, it was found that there was a linear relationship between the value of n and the difference of the width of the bone canal. With the increase of the value of n, the difference of the width of the bone canal gradually became larger. The median difference of the width of the middle and superior tunnel was negative, while the median difference of the width of the middle and inferior tunnel was positive. During the follow-up, we found that there were no statistical differences in IKDC, Lysholm and Tegner scores among the three groups one year after surgery (P > 0.05).@*CONCLUSION@#Twelve months after surgery, compared with group B (fixed loop group) and group C (fixed loop group), group A (adjustable loop group) had less bone tunnel widening.In groups A, B and C, as the length of the loop in coarse bone tunnel gradually increased, the width of bone tunnel became more significant. At the end of 12 months follow-up after anterior cruciate ligament reconstruction, the medial and inferior femoral tunnel was significantly wider than immediately after surgery, and the medial and superior femoral tunnel had gradually begun to undergo tendon-bone healing. There was no significant difference in knee function scores among groups A, B, and C in the follow-up 12 months after surgery.

Finite element analysis of the graft stresses after anterior cruciate ligament reconstruction / 北京大学学报(医学版)

OBJECTIVE@#To explore the stress distribution characteristics of the graft after anterior cruciate ligament (ACL) reconstruction, so as to provide theoretical reference for the surgical plan of ACL reconstruction.@*METHODS@#Based on 3D MRI and CT images, finite element models of the uninjured knee joint and knee joint after ACL reconstruction were established in this study. The uninjured knee model included femur, tibia, fibula, medial collateral ligament, lateral collateral ligament, ACL and posterior cruciate ligament. The ACL reconstruction knee model included femur, tibia, fibula, medial collateral ligament, lateral collateral ligament, ACL graft and posterior cruciate ligament. Linear elastic material properties were used for both the uninjured and ACL reconstruction models. The elastic modulus of bone tissue was set as 17 GPa and Poisson' s ratio was 0.36. The material properties of ligament tissue and graft were set as elastic modulus 390 MPa and Poisson's ratio 0.4. The femur was fixed as the boundary condition, and the tibia anterior tension of 134 N was applied as the loading condition. The stress states of the ACL of the intact joint and the ACL graft after reconstruction were solved and analyzed, including tension, pressure, shear force and von Mises stress.@*RESULTS@#The maximum compressive stress (6.34 MPa), von Mises stress (5.9 MPa) and shear stress (1.83 MPa) of the reconstructed ACL graft were all at the anterior femoral end. It was consistent with the position of maximum compressive stress (8.77 MPa), von Mises stress (8.88 MPa) and shear stress (3.44 MPa) in the ACL of the intact knee joint. The maximum tensile stress of the graft also appeared at the femoral end, but at the posterior side, which was consistent with the position of the maximum tensile stress of ACL of the uninjured knee joint. More-over, the maximum tensile stress of the graft was only 0.88 MPa, which was less than 2.56 MPa of ACL of the uninjured knee joint.@*CONCLUSION@#The maximum compressive stress, von Mises stress and shear stress of the ACL graft are located in the anterior femoral end, and the maximum tensile stress is located in the posterior femoral end, which is consistent with the position of the maximum tensile stress of the ACL of the uninjured knee joint. The anterior part of ACL and the graft bore higher stresses than the posterior part, which is consistent with the biomechanical characteristics of ACL.

Reconstrucción del labrum de la cadera con injerto de ligamento redondo de la cabeza femoral. Presentación de un caso y descripción de la técnica quirúrgica / Hip labral reconstruction using the ligamentum teres capitis: Case report and surgical technique

Las lesiones del labrum de la cadera con sustancia insuficiente se pueden tratar con técnicas de aumento, de reconstrucción o con trasplante de tejidos. Si el remanente labral es muy escaso, las opciones reconstructivas serían las más adecuadas. Se presenta el caso de una paciente de 40 años con dos cirugías artroscópicas previas fallidas por lesión labral, que fue sometida a una luxación controlada de cadera, siguiendo la técnica original descrita por Ganz, y a la resección del ligamento redondo de la cabeza femoral para cubrir el defecto del labrum. Según nuestro conocimiento, se trata del primer reporte de reconstrucción labral utilizando el ligamento redondo de la cabeza femoral en nuestro medio. Pese a los resultados poco alentadores en pacientes con cirugías previas, la reconstrucción labral utilizando el ligamento redondo ha mostrado ser una alternativa viable. Nivel de Evidencia: IV

Labral tears with insufficient substance can be treated with augmentation techniques, reconstruction, or grafting techniques. If the remnant labrum is very scarce, reconstructive options would be the most appropriate. We present the case of a 40-year-old female patient who had undergone two failed hip arthroscopies due to labral tears. Following the original technique described by Ganz, a surgical hip dislocation was performed, and the Ligamentum Teres Capitis was resected to cover the labral defect. To our knowledge, this is the first report of labral reconstruction using the Ligamentum Teres Capitis in our literature. Despite poorly reported outcomes in patients with previous procedures, surgical repair using the Ligamentum Teres Capitis has proven to be a viable option. Level of Evidence: IV

Impact of proximal femoral shape on leg length discrepancy after total hip arthroplasty / 中国骨伤

OBJECTIVE@#To investigate the effect of different proximal femoral shapes on leg length discrepancy(LLD) after total hip arthroplasty(THA).@*METHODS@#Total 131 patients with osteoarthritis or osteonecrosis received unilateral biological total hip arthroplasty from June 2013 to June 2019. All patients' age, sex, side and pelvis anteroposterior digital radiography were retraspectively analyzed. There were 69 males and 62 females, 57 cases of left hip and 74 cases of right hip. The age ranges from 25 to 89 with an average age of 62 years. There were 48 cases of osteoarthritis and 83 cases of osteonecrosis. In this study, femoral cortical index (FCI) was used as the classification of proximal femoral shape, and bilateral lower limb length differences were measured by preoperative and postoperative pelvis anteroposterior digital radiography. Grouping according to FCI:> 0.6 was Dorr A group, 0.5 to 0.6 was Dorr B group, 0.6, the postoperative LLD was 6.30 mm (IQR 1.00 to 10.95 mm). When FCI was 0.5 to 0.6, the postoperative LLD was 5.85 mm(IQR-0.55 to 8.90 mm). FCI<0.5, the postoperative LLD was 1.95 mm(IQR -2.50 to 6.68 mm). LLD comparison of different proximal femoral shape was statistically significant (@*CONCLUSION@#High FCI increases the risk of lower extremity prolongation after surgery on the affectedside, while low FCI reduces the risk of lower extremity prolongation after surgery on the affected side. The surgeon can assess the shape of the proximal femur of the patient preoperatively and inform the patient in advance of possible changes in leg length of both lower extremities after total hip replacement.

Comparison of femoral tunnel and early curative effect analysis between arthroscopic three approach and traditional anteromedial portal for reconstruction of anterior cruciate ligament / 中国骨伤

OBJECTIVE@#To study the three-approach and traditional anterior medial technique to establish the femoral tunnel of position, length, and coronal angle and the early efficacy of anterior cruciate ligament reconstruction.@*METHODS@#Through retrospective research, from December 2018 to June 2019, a total of 36 patients diagnosed with simple anterior cruciate ligament tear and undergoing surgery were collected. All patients had a clear history of knee sprains and were divided into two groups. A group of 16 patients, including 11 males and 5 females, with an average age of (30.13±6.54) years and an injury time of 7 to 60 (30.19±15.78) days, three-approach technique was used to drill the femoral tunnel to reconstruct the anterior cruciate ligament. Another group of 20patients, including 15 males and 5 females, with an average age of (30.80±8.60) years, and an injury time of 7 to 60 (27.35±15.50) days, the traditional anterior medial approach was used to drill the femoral tunnel to reconstruct anterior cruciate ligament. CT 3D reconstruction technique was used to evaluate the femoral tunnel and the knee joint function was evaluated by Lysholm score of the knee joint.@*RESULTS@#All patients achieved primary healing after the surgical incision. No femoral tunnel fracture, vascular and nerve damage, difficulty in graft passage during the operation, and venous thrombosis occurred. All 36 patients were followed up on an outpatient basis, with a follow up period of 9 to 15 (12.00±2.83) months. Three-dimensional CT reconstruction was used to evaluate the femoral tunnel of the patients. The position of the femoral tunnel was described using the quartile method as the three-approach group:the lower (27.83±1.97) % of the femoral condyle and the posterior (25.57±3.20) %;the traditional approach group:the lower (28.38±3.21) % of the femoral condyle and the posterior (26.23±3.20) %. Bone tunnel length, three-approach group:(35.20±5.52) mm in total length, (23.20±2.07) mm in thick bone tunnel;traditional approach group:(34.60±4.26) mm in total length, (22.56±2.50) mm in thick bone tunnel. Coronal plane angle, three-approach group:(47.93±5.98) °;traditional approach group:(41.78±6.62) °. Knee joint Lysholm score, three-approach group:48.67±4.18 before surgery;97.00±2.48 at last follow up;traditional approach group:49.75±5.33 before surgery, 97.30±2.68 at last follow up, there were significant differences before and after surgery, no significant statistical difference between two groups.@*CONCLUSION@#The positions of the femoral tunnel drilled by the two methods were within the range of the anatomic stop of the anterior cruciate ligament, and there was no statistical difference. Compared with the traditional anterior medial approach, the coronal plane angle of the femoral tunnel drilled by the three-approach approach is relatively large, and there were no statistical differences in the length of the tunnel, the early postoperative effect of the two surgical methods, and the operation time. But the three approach has a wider and clearer vision. In addition, the knee flexion angle required for drilling the femoral tunnel during surgery is significantly smaller than that of traditional approach technology, which reduces the difficulty of surgery.

Application of sliding osteotomy in total knee arthroplasty for patients with extra-articular femoral deformity / 中国骨伤

OBJECTIVE@#In order to observe the clinical effects of sliding osteotomy for patients with severe knee osteoarthritis and varus knee due to complex femoral extra-articular deformity to achieve the medial and lateral soft tissue balancing during total knee arthroplasty.@*METHODS@#From June 2014 to January 2018, a total of 22 patients with severe knee osteoarthritis and complex extra-articular malformation of femurs were treated with total knee arthroplasty. There were 5 males and 17 females in this group, aged 48 to 76 years old, with an average age of (61.3±13.8) years old. All the patients had varus deformities caused by extra-articular deformities of femur. Hip-knee-ankle(HKA) angle was(158.8±9.7) ° before operation, and the average Knee Society Score (KSS) clinical score was 32.6±6.1;KSS function score was 35.8 ±9.6;the average Hospital for Special Surgical (HSS) score was 39.7±4.6;the average range of motion before operation was (80.6±10.7) °. The mechanical alignment method was used in joint replacement. The flexion space was balanced first. The coronal plane vertical sliding osteotomy was performed on the medial femoral condyle for the imbalance of coronal plane. The sliding distance of the osteotomy block was determined by straightening the gap between the inner and outer sides of the space until the space was balanced. After the separated segments were fixed with several screws, the prosthesis was installed as usual.@*RESULTS@#The wounds of all patients healed in the first stage, and no wound complications occurred. All the 22 patients were followed up, and the duration ranged from 18 months to 3 years with an average of (28.2±10.1) months. X-ray showed that the fracture line disappeared for 2 to 5(3.5±1.5) months without nonunion. HKA angle measured at the latest follow up was (178.8±0.7) °, which wassignificantly different from that before operation. The HSS score was 91.3 ±6.0;KSS clinical score 93.7±3.5;KSS functional score 81.2±6.5;and the average range of motion of knee joint was(121.7±11.6) °, which was statistically significant compared with that before operation.@*CONCLUSION@#For severe knee osteoarthritis patients with complex femoral extra-articular deformity, sliding osteotomy is performed. For severe varus deformity, downward sliding the medial femoral condyle is performed. The operation is relatively simple and the damage is small. It is easy to achieve the balance of internal and external soft tissue in flexion extension space. The short-term clinical effect is satisfactory.

Analysis on muscle force and injured femoral reduction force based on new muscle tendon model / 生物医学工程学杂志

Robot-assisted fracture reduction usually involves fixing the proximal end of the fracture and driving the distal end of the fracture to the proximal end in a planned reduction path. In order to improve the accuracy and safety of reduction surgery, it is necessary to know the changing rule of muscle force and reduction force during reduction. Fracture reduction force was analyzed based on the muscle force of femoral. In this paper, a femoral skeletal muscle model named as PA-MTM was presented based on the four elements of skeletal muscle model. With this, pinnate angle of the skeletal muscle was considered, which had an effect on muscle force properties. Here, the muscle force of skeletal muscles in different muscle models was compared and analyzed. The muscle force and the change of the reduction force under different reduction paths were compared and simulated. The results showed that the greater the pinnate angle was, the greater the influence of muscle strength was. The biceps femoris short head played a major role in the femoral fracture reduction; the force in the

Application of individualized setting of femoral opening point and valgus angle in artificial total knee arthroplasty for patients with external femoral arch / 中国骨伤

OBJECTIVE@#To investigate whether shifting the femoral opening point and setting a personalized femoral valgus angle can improve the lower limb force line of total knee arthroplasty (TKA) patients with external femoral arch.@*METHODS@#From March 2016 to October 2018, 50 patients (55 knees) with osteoarthritis with genu varus deformity combined with external femoral arch for TKA were selected. There were 10 males and 40 females. The age ranged from 63.1 to 80.5 years old, with an average of (67.8±5.8) years old. Forty-five cases were unilateral and 5 cases were bilateral. The osteoarthritis stages of 55 knees were Kellgren-Lawrence grade Ⅲ to Ⅳ; and the course of disease ranged from 2 to 10 years. PreoperativeSpecial Surgery (Hospital for Special Surgery) scores:pain was 15.20±3.52; function was 8.30±2.96;mobility was 10.15±2.85;muscle strength was 4.20±1.95;flexion deformity was 5.50±3.05;stability was 6.15±2.20; total score was 47.93±3.39. The external femoral arch angle ranged from 6.4° to 16.7°, with a mean of (10.63±2.29) °. The tibiofemoral angle ranged from 7.4° to 12.6°, with a mean of (12.04±3.59)°. The anatomical distal femoral angle ranged from 83.10° to 91.20°, with a mean of (84.55± 1.66)°. And the distance from the center of the knee joint to the lower limb line of force ranged from 2.01 to 6.00 cm, with a mean of (3.57±1.12) cm. During the replacement surgery, the femoral opening point and the valgus angle were individually set to obtain a good line of force of the lower limbs.@*RESULTS@#Before the operation, the distance of femoral opening point ranged from 0.24 to 0.74 cm, with a mean of (0.54±0.10) cm. The distance between the internal and external condyles of the femur ranged from 6.86 to 8.12 cm, with a mean of (7.27±0.27) cm. The preoperative valgus correction angle (VCA) ranged from 7.20° to 13.80°, with a mean of (9.38±1.38) °. The post-correction valgus correction angle' (VCA') ranged from 6.10° to 9.50°, with a mean of (7.36±0.82) °. All patients were followed up, and the duration ranged from 3 to 36 months, with an average of (13.5±5.8) months. All patients obtained good knee function after operation. Three months after operation, HSS scores included pain of 25.30±3.05, function of 18.25±2.05, mobility of 16.05±0.75, muscle strength of 6.20±2.10, flexion deformity of 8.80±1.85, stability of 8.20±1.75; and the total score ranged from 90.00 to 93.00, with an average of 91.82±0.98. The total score was higher than that before operation (@*CONCLUSION@#In TKA combined with external femoral arch, good lower limb force line and knee joint function can be obtained by externally shifting the femoral opening point and setting a personalized femoral valgus angle.

Bone tunnel positions in anterior cruciate ligament reconstruction evaluated by three-dimensional CT reconstruction based on Mimics software:modified transtibial versus anteromedial portal technique / 中国骨伤

OBJECTIVE@#To compare the femoral and tibial tunnel positions of anterior cruciate ligament reconstruction using the modified transtibial (MTT) technique and anteromedial (AM) portal technique.@*METHODS@#Between January 2017 and September 2020, 78 patients with anterior cruciate ligament rupture underwent single-bundle reconstruction with the modified transtibial technique in 39 cases (group MTT) and through anteromedial approach in 39 cases (group AM). There were 25 males and 14 females in group MTT, with an average age of (37.0±2.3) years old; 27 males and 12 females in group AM, with an average age of (37.5±2.2) years old. CT scan of the affected knee was conducted one week after the surgery to measure and compare the femoral tunnels positioning (Fx, Fy), tibial tunnels positioning in the frontal plane(Tx1), tibial tunnels positioning in the sagittal plane (Ty1), and tibial tunnels positioning in the axial plane (Tx2, Ty2) in patients undergoing anterior cruciate ligament reconstruction through Mimics software.@*RESULTS@#Three-dimensional CT reconstruction after the surgery showed that the average Fx and Fy were(25.2±2.1)% and (34.9±3.0)% respectively and the Tx1 and Ty1 were (45.5±3.3)% and (44.7± 3.0)% respectively, while the Tx2 and Ty2 were (47.0±3.0)% and (39.9±4.2)% respectively in group MTT. In group AM, the average Fx and Fy were (26.0±2.0)% and (36.1±3.9)% respectively and the Tx1 and Ty1 were (46.5±3.1)% and (45.6± 3.1)% respectively, while the Tx2 and Ty2 were (47.4±2.5)% and (39.6±3.9)% respectively. There were no statistically significant differences in the femoral and tibial tunnels between the two groups (@*CONCLUSION@#Both the MTT and AM technique can achieve good anatomical positioning of the femoral and tibial tunnels, without significant differences in the positioning of the bone tunnels.