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Objective To establish a three-dimensional(3D) finite element model of cervical vertebrae (C1-7), and study its biomechanical properties under muscle force by cervical traction, so as to provide references for clinical treatment. Methods On the basis of nonlinear finite element model of normal cervical vertebrae and combined with clinical traction methods, cervical traction at the extension angle of 0°, 10°, 20°, 30°, 40° under the same traction weight, was simulated by finite element analysis (FEA) software to obtain and select the joint force and muscle force that were appropriate for FEA on the model. Results In the process of cervical extension by traction, under the muscle force, the average maximum equivalent stress of cervical vertebrae, intervertebral disc and uncovertebral joints increased by 4.86, 1.79, 0.69 MPa, respectively, and the average maximum relative displacement of cervical vertebrae in sagittal and vertical axis direction increased by 11.1, 1.26 mm, respectively. The biomechanical properties of cervical traction were similar to the FEA results reported in the literature. Conclusions Neck muscles play an active role in promoting the stress and displacement of cervical vertebrae, intervertebral discs and uncovertebral joints and it should be taken into consideration when performing cervical traction in clinic. In addition, the traction angle should not be too large: 0°-20° is generally recommended as a relatively safe angle range at the initial stage.
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Objective To evaluate the biomechanical properties of 3D printed individualized titanium alloy pelvic prosthesis in static and gait states by the method of finite element analysis. Methods Three patients with different types of pelvic tumors were treated by hemi-pelvic arthroplasty with resection of hemi-pelvis. CT and MRI were performed before the surgery, and the corresponding individualized titanium alloy pelvic prostheses were designed. The pelvic models were reconstructed with 3D reconstruction technique, and then assembled with the individualized pelvic prostheses. The human skeletal muscle model was established by AnyBody software to perform gait dynamics analysis. The stress distribution and stress concentration areas of 3 reconstructed pelvic models in static and gait states were obtained by ABAQUS. Results Under both static and gait conditions, the maximum stress of the 3 pelvic prostheses was smaller than the yield strength of the titanium alloy. The pelvic ring of the reconstructed pelvis could meet the rule of stress conduction. The patients’ daily life returned to normal condition after the surgery. Conclusions The effect of 3D prosthetic titanium prosthesis on recovery of pelvic ring is satisfactory, and its effectiveness and stability can meet the requirement of human biomechanics. The analytic results can provide references for clinicians and prosthesis designers.
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Objective To establish a three-dimensional(3D) finite element model of cervical vertebrae (C1-7),and study its biomechanical properties under muscle force by cervical traction,so as to provide references for clinical treatment.Methods On the basis of nonlinear finite element model of normal cervical vertebrae and combined with clinical traction methods,cervical traction at the extension angle of 0°,10°,20°,30°,40° under the same traction weight,was simulated by finite element analysis (FEA) software to obtain and select the joint force and muscle force that were appropriate for FEA on the model.Results In the process of cervical extension by traction,under the muscle force,the average maximum equivalent stress of cervical vertebrae,intervertebral disc and uncovertebral joints increased by 4.86,1.79,0.69 MPa,respectively,and the average maximum relative displacement of cervical vertebrae in sagittal and vertical axis direction increased by 1 1.1,1.26 mm,respectively.The biomechanical properties of cervical traction were similar to the FEA results reported in the literature.Conclusions Neck muscles play an active role in promoting the stress and displacement of cervical vertebrae,intervertebral discs and uncovertebral joints and it should be taken into consideration when performing cervical traction in clinic.In addition,the traction angle should not be too large:0.-20. is generally recommended as a relatively safe angle range at the initial stage.
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Objective To establish a three-dimensional(3D) finite element model of cervical vertebrae (C1-7),and study its biomechanical properties under muscle force by cervical traction,so as to provide references for clinical treatment.Methods On the basis of nonlinear finite element model of normal cervical vertebrae and combined with clinical traction methods,cervical traction at the extension angle of 0°,10°,20°,30°,40° under the same traction weight,was simulated by finite element analysis (FEA) software to obtain and select the joint force and muscle force that were appropriate for FEA on the model.Results In the process of cervical extension by traction,under the muscle force,the average maximum equivalent stress of cervical vertebrae,intervertebral disc and uncovertebral joints increased by 4.86,1.79,0.69 MPa,respectively,and the average maximum relative displacement of cervical vertebrae in sagittal and vertical axis direction increased by 1 1.1,1.26 mm,respectively.The biomechanical properties of cervical traction were similar to the FEA results reported in the literature.Conclusions Neck muscles play an active role in promoting the stress and displacement of cervical vertebrae,intervertebral discs and uncovertebral joints and it should be taken into consideration when performing cervical traction in clinic.In addition,the traction angle should not be too large:0.-20. is generally recommended as a relatively safe angle range at the initial stage.
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Objective To evaluate the biomechanical properties of 3 D printed individualized titanium alloy pelvicprosthesis in static and gait states by the method of finite element analysis.Methods Three patients with different types of pelvic tumors were treated by hemi-pelvic arthroplasty with resection of hemi-pelvis.CT and MRI were performed before the surgery,and the corresponding individualized titanium alloy pelvic prostheses were designed.The pelvic models were reconstructed with 3D reconstruction technique,and then assembled with the individualized pelvic prostheses.The human skeletal muscle model was established by AnyBody software to perform gait dynamics analysis.The stress distribution and stress concentration areas of 3 reconstructed pelvic models in static and gait states were obtained by ABAQUS.Results Under both static and gait conditions,the maximum stress of the 3 pelvic prostheses was smaller than the yield strength of the titanium alloy.The pelvic ring of the reconstructed pelvis could meet the rule of stress conduction.The patients' daily life returned to normal condition after the surgery.Conclusions The effect of 3D prosthetic titanium prosthesis on recovery of pelvic ring is satisfactory,and its effectiveness and stability can meet the requirement of human biomechanics.The analytic results can provide references for clinicians and prosthesis designers.
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Journal of Medical Biomechanics was founded in 1986. As a technical periodical, the journal aims at reflecting the latest scientific and clinical achievement and progress in the field of biomechanics, and promoting academic exchange of biomechanics both in China and abroad. By June 2016, the journal has officially published a total of 31 volumes and 124 issues, and great progress has been achieved in its publishing quality and academic influence. In this article, the 30-year development of the journal is reviewed, and future work is prospected in the aspect of improving quality, digitalization and internationalization of the journal.
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Objective To observe changes of surface electromyography (sEMG) in cervical traction under different loading weight and at different angles, and compare the muscle activity changes obtained by experiment with simulation results obtained by AnyBody cervical modeling, so as to verify the rationality of the simulation results. Methods Ten young volunteers with supine cervical traction were selected to test the sEMG signals of bilateral sternocleidomastoid (SCM) and upper trapezius (UT) muscles by using the JE-TB0810 surface EMG device. The average EMG (AEMG) and mean power frequency (MPF) were used to analyze the variation patterns of sEMG in cervical spine. Results The AEMG values of SCM and UT muscles increased as the loading weight and traction angles increasing, with a statistically significant difference (P0.05). The experimental results were consistent with muscle force activity characteristics of SCM and UT muscles by modeling and simulation of cervical traction. Conclusions The simulation results are reasonable. The traction weight should be loaded reasonably according to the excitation and fatigue of the cervical muscles in clinic. This can both reach the treatment effect and improve the patient’s comfort, which will provide an important reference for further development and improvement of the cervical traction device.
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atigue is a common phenomenon in many medical and neurologic diseases. Understanding the origins of fatigue in these diseases is of great guiding significance in developing targeted interventions for muscle fatigue. In this review, the central origin (including all the supraspinal and spinal physiological phenomena capable of inducing a decrease in motoneuron excitation) and the peripheral origin (including neuromuscular transmission, propagation of action potentials in muscle, excitation-contraction coupling) of muscle fatigue were summarized. The methods of assessing the central or peripheral origin of muscle fatigue were discussed, including the direct measurement (maximal voluntary contraction force, twitch force) and the indirect tests (twitch interpolation, electromyography, motor cortical stimulation).
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Objective To design and fabricate novel mesoporous calcium silicate/calcium phosphate cement (MCS/CPC) scaffolds for bone repair and investigate their in vitro biomechanical properties under different external forces. Methods MCS and CPC in certain proportion were mixed to form plotting material, and the composite MCS/CPC scaffolds with pore size of 350 μm and 500 μm were fabricated by 3D bioplotting technique, respectively. Surface topographies of the scaffolds were observed by scanning electron microscope (SEM). The compressive strength and mechanical properties of the scaffolds under dynamic cyclic loads at different frequencies were studied through universal mechanical testing machine and dynamic mechanical analysis instrument. Results MCS/CPC scaffolds with controllable macroporous structures could be fabricated by 3D bioplotting technique. Scaffolds with pore size of 350 μm had higher compressive strength ［(9.8±0.39) MPa］ and compressive modulus ［(132.5±4.3) MPa］. In addition, at the loading frequency of 1-100 Hz, scaffolds with pore size of 350 μm had a higher storage modulus. ConclusionsMCS/CPC scaffolds with pore size of 350 μm fabricated by 3D bioplotting technique possess not only regular pore connectivity and high compressive strength, but also structural stability under dynamic loads, which are promising as novel biomaterials for bone repair.
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Individualized treatment is an important direction in the development of orthopaedics. Either the application of the custom-made implants or using patient-specific surgical instrument to assist the implantation of conventional prosthesis, theoretically, could improve the matching between the implants and adjacent bony structures, so as to improve the overall function of the patients. However, the superiority of individualized treatment in theory cannot compensate its complexity and time-lag caused by individualized therapy in preoperative planning, design, manufacturing, etc. Therefore, individualized treatment is just a concept in most of the time. With the development of image technology and the maturity of 3D printing technique, the efficiency of individualized design and manufacturing is expected to be improving significantly, which shows the potential to translate this elegant concept into a practical principle.
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Objective To explore the mechanism of reactive oxygen species (ROS) generation on apoptosis of human osteoarthritic chondrocytes induced by cyclic stretch in vitro. Methods The human osteoarthritic chondrocytes were subjected to cyclic stretch at the frequency of 0.5 Hz with 20% elongation. The chondrocytes without cyclic stretch were used as a control. ROS generation in chondrocytes was inhibited by the antioxidant, N-acetyl-L-cysteine (NAC) and potentiated by the glutathione depleter, DL-buthionine-［S,R］-sulfoximine (BSO). Apoptosis was detected by flow cytometry. Intracellular ROS was detected using DCFH-DA and caspase-9 activity was measured using spectrophotometry. Results The cyclic stretch at the frequency of 0.5 Hz with 20% elongation induced ROS generation, and activation of caspase-9 and apoptosis in human osteoarthritic chondrocytes were significantly increased (P<0.05). The inhibition or potentiation of intracellular ROS by NAC or BSO could obviously inhibit or improve caspase-9 activity and apoptosis in chondrocytes under cyclic stretch (P<0.05). Conclusions Cyclic stretch-induced apoptosis in human osteoarthritic chondrocytes is mediated by ROS generation and activation of caspase-9. Suppression of ROS can prevent chondrocytes from apoptosis induced by cyclic stretch.
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Objective To establish a three-dimensional (3D) dynamic model of temporomandibular joint (TMJ) based on data collected from the TMJ movement with multi-level two-dimensional (2D) dynamic magnetic resonance imaging (MRI) and make biomechanical analysis. Methods GE Signa 1.5T TwinSpeed superconductive magnetic resonance scanner was used. TMJs of 2 asymptomatic male volunteers were chosen to be examined with MRI. All the images were imported to the Mimics software. 3D dynamic model of the TMJ was built, and the relationship between the magnitude of mouth opening and the disc transverse diameter was analyzed using linear fitting. Results The 3D dynamic model of TMJ was successfully established. The disc-condyle relationship and the dynamic morphological change of the TMJ disc were showed clearly in this model. The linear fitting equations were y=-0.03x+14.44 (R2=0.591) and y=-0.061x+13.48 (R2=0.306) from volunteers 1 and 2, respectively. A linear trend was observed regarding the relationship between mouth opening position and articular disc transverse diameter. The contact of the condyle surrounded by the TMJ disc varied inversely with the magnitude of mouth opening; the longitudinal diameter of TMJ disc changed along with the magnitude of mouth opening. In the process of mouth opening, the thickest longitudinal diameter of the joint disc was at the middle part of post-zone. The most remarkable changes of the longitudinal diameter of TMJ disc were found at the outer part of the post-zone and the inner part of the mid-zone. Conclusions The 3D dynamic model of TMJ was built successfully to observe the TMJ movement dynamically with 2D dynamic MRI. The model showed the disc-condyle relationship intuitively and precisely, and could be used as an alternative method to make up for the shortage of the 2D static MRI.
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Objective To develop a biological canulated screw and evaluate its mechanical properties, so as to provide theoretical basis for the bio therapy of fracture with enrichment technique of bone marrow stem cells, which could be diffused through the canula, particularly for promoting bone union of femoral neck fracture and preventing avascular necrosis of femoral head. Methods TC4 titanium alloyed canulated cancellous screw (7.3 mm in diameter) commonly used for internal fixation of femoral neck fracture was improved by designing an end sealing plug and side holes in a 900 mm-long canulated screw. The side holes were arranged along the axis of screw, and the first side hole was 20 mm away from the screw tip. The distance between each side hole was 10 mm, and the number of side holes ranged from 0 to 6. The screws without holes were tested as control, and the rest were divided into two groups, i.e., group A: force direction parallel to the side hole, group B: force direction perpendicular to the side hole. Three point bending test on the screw was conducted by using Instron material testing machine, so as to study the relationship between the mechanical strength of the screw and the number of side holes, and the loading direction. Results (1) When the force direction was parallel to the side hole, which was confined within 0, 1 or 2, the bending deformation of the screw reached 3 mm, and no differences were found in the maximum loads and elastic modulus of the screw. However, when the number of side holes was increased to 3 or more, a significant reduction in the maximum load and elastic modulus of the screw was found (P＜0.05). (2) When the force direction was perpendicular to the side hole, which was confined within 0,1 or 2, and the bending deformation of the screw reached 3 mm, no significant differences were found in the maximum loads of the screw. While no significant difference was found in the elastic modulus of the screw when the side hole was 0, 1, 2 and 3. With an increase in the number of side holes, the maximum loads (≧ 3 side holes) and elastic modulus (≧ 4 side holes) were significantly reduced (P＜0.05). (3) When the force direction was perpendicular to the side hole and the number of side holes was 3 or more, the maximum loads and elastic modulus of the screw were all significantly higher than the screw with the same number of side hole under force direction parallel to the side hole. Conclusions (1) For achieving better mechanical properties of the screw, the number of side holes in titanium alloyed canulated cancellous screw (7.3 mm in diameter) should be within 2; (2) If the number of side holes was equal or over 3, screws under force direction perpendicular to the side hole could provide better mechanical properties than screws under force direction parallel to the side hole. This study may provide some theoretical evidence and support for future clinical development and practice of the biological canulated screw.
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<p><b>BACKGROUND</b>Mortality rates for patients with gas gangrene from trauma or surgery are as high as 25%, but they increase to 50%-80% for patients injured in natural hazards. Early diagnosis and treatment are essential for these patients.</p><p><b>METHODS</b>We retrospectively analyzed the clinical characteristics and therapeutic results of 19 patients with gas gangrene of the limbs, who were injured in the May 2008 earthquake in the Wenchuan district of China's Sichuan province and treated in our hospital, to seek how to best diagnose and treat earthquake-induced gas gangrene.</p><p><b>RESULTS</b>Of 226 patients with limbs open injuries sustained during the earthquake, 53 patients underwent smear analysis of wound exudates and gas gangrene was diagnosed in 19 patients. The average elapsed time from injury to arrival at the hospital was 72 hours, from injury to definitive diagnosis was 4.3 days, and from diagnosis to conversion of negative findings on wound smear analysis to positive findings was 12.7 days. Anaerobic cultures were also obtained before wound closure. The average elapsed time from completion of surgery to recovery of normal vital signs was 6.3 days. Of the 19 patients, 16 were treated with open amputation, two with closed amputation, and 1 with successful limb salvage; 18 patients were successfully treated and one died.</p><p><b>CONCLUSIONS</b>In earthquakes, rapid, accurate screening and isolation are essential to successful treatment of gas gangrene and helpful in preventing nosocomial diffusion. Early and thorough debridement, open amputation, and active supportive treatment can produce satisfactory therapeutic results.</p>
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Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Humans , Male , Middle Aged , Young Adult , Earthquakes , Extremities , Pathology , General Surgery , Gas Gangrene , Diagnosis , General Surgery , Retrospective StudiesABSTRACT
<p><b>OBJECTIVES</b>Knee osteoarthritis (OA) is a major cause of pain and functional limitation. Short-term Baduanjin () exercise had been testified to be beneficial to the disease. This study conducted an initial assessment of the one-year Baduanjin exercise on knee OA.</p><p><b>METHODS</b>The recruited patients practiced Baduanjin at the community recreational center. Sessions were held for 30 min five times a week for one year. Knee pain, stiffness, physical disability, general health, knee extensors and flexors strength, and aerobic ability were measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Medical Outcomes Study Short Form-36 (SF-36), the 6-Minute Walk Test (6-MWT), and the Isokinetic Strength of the Knee Extensors and Flexors (ISKEF). Body mass index (BMI) was also calculated before and after the study period for comparison.</p><p><b>RESULTS</b>Twenty-eight patients signed the informed consent. Six patients withdrew from the trial. Twenty-two patients (29 knees) completed the one-year study. After one-year Baduanjin exercise, WOMAC pain (132.0±69.6 vs. 56.2±67.6, P=0.000), stiffness (64.7±54.8 vs. 22.3±34.6, P=0.000), and physical function subscales (386.1±275.8 vs. 182.0±235.7, P=0.003); SF-36 body pain (45.7±20.0 vs. 57.4±17.9, P=0.005), general health (50.5±20.0 vs. 62.1±16.1, P=0.004), role emotional (64.4±26.1 vs. 73.5±21.3, P=0.047), and health transition (3.3±1.0 vs. 2.6±1.0, P=0.008); BMI (25.0±2.9 vs. 24.4±2.9, P=0.032); 6-MWT (565.7±94.6 vs. 610.5±66.7, P=0.036); and ISKEF Peak Torque (the Knee Extensors: 60.5±25.5 vs. 76.8±31, P=0.000; the Knee Flexors: 29.3±15.9 vs. 37.1±15.8, P=0.001) were significantly improved. No adverse effects resulted from the exercise.</p><p><b>CONCLUSIONS</b>It suggested that the long-term Baduanjin could be a feasible and safe exercise option for knee OA.</p>
Subject(s)
Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Exercise Therapy , Osteoarthritis, Knee , TherapeuticsABSTRACT
Objective To investigate the gait stability of healthy old and young adult volunteers during walking using the nonlinear time series analysis method so as to comprehensively assess the dynamic balance of human and provide important references for the prediction of fall risk. Methods The Vicon motion capture system was used to collect three-dimensional kinematic data of healthy volunteers (seven old subjects and ten young subjects) at different walking speed (80%, 100%, 120% of the natural walking speed). The anterior-posterior and medio-lateral motions of the seventh cervical and tenth thoracic vertebrae, as well as the flexion-extension and abduction-adduction angles of the lower extremity joints, were obtained from 30 consecutive gait cycles to calculate the largest Lyapunov exponents and analyze the difference of gait stability between the old and young group and the influence of walking speed on gait stability. Results The gait stability in the young group was better than that in the old group, and there were significant differences in certain motion segments (P＜0.01). The gait stability in both groups were reduced with the increase of speed (P＜0.05). Conclusions The largest Lyapunov exponent based on nonlinear time series analysis method can be used to effectively and quantitatively analyze the gait stability of each motion segment in human during walking.
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This paper expounds the statistical work on artificial joint failure and their primary results in China and abroad. From the view of clinical demand, biomechanics and engineering, the paper proposes that it is the basic technology, manufacturing techniques and clinical conditions that lead to artificial joint failure. The paper also elaborates the demand on further improving the clinical medicine of artificial joint and prosthesis technology, and presents some suggestions to promote the domestic statistics work on artificial joint failure.
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Objective To measure the bone mass, the shape of bones and the bone strength through segmentation of the bone cortex in CT images, and to calculate the corresponding parameters in histomorphometry. Methods CT images were first interpreted through the DCMTK to draw information of the corresponding images, then the OpenCV are used for preprocessing on the basis of ROI (range of interest), and the texture features of the image were extracted as the input vector. Results of the manual segmentation were used as the mentor signal to train BP neural network, which were then used for segmenting the bone cortex in a sequence of CT images. Results of the segmentation were further processed and displayed. Results The segmentation efficiency of the bone cortex in CT images through neural network met the needs of the practical application. The separation results showed an obvious shape of the bone cortex with easy distinguishing from the surrounding tissues, which could satisfy the demand of the clinical diagnosis. Conclusions When the texture features of the bone cortex are evident, this method can achieve a more satisfying segmentation effect with smooth contours, high segmentation accuracy and strong adaptability. With less artificial intervention in the process of the image segmentation, this method can be used for batch CT image segmentation of a complete set of the bone cortex. The inadequacy of the method lies in relatively longer training time demanded for the neural network training.
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Objective To investigate the effect of different perfusion flow rates on proliferation and osteoblastic differentiation of human mesenchymal stem cells (hMSCs) in large scale β-TCP (tricalcium phosphate) scaffold at perfusion bioreactor. Methods hMSCs isolated from iliac bone marrow aspiration were loaded into large scale β-TCP scaffold and cultured in perfusion bioreactor at the perfusion flow rate of 3, 6 or 9 mL/min for 15 days. The culture media were collected for D-glucose consumption assay every 3 days. After perfusion culture for 15 days, the cell-scaffold composites were harvested for assessment of cell viability by MTT colorimetric method, SEM observation and osteogenic gene expression by real-time PCR. Results The proliferation of hMSCs assayed by daily glucose consumption showed that at early stage of culture, cells proliferated faster at flow rate of 9 mL/min than at 3 or 6 mL/min (P<0.001); while at late stage of culture, cells proliferated faster at flow rate of 6 mL/min (P<0.05). The cell viability indicated that the cell-scaffold composites at flow rate of 6 mL/min exhibited the most viable cells (P<0.001). SEM indicated that all the macropores of the scaffold at different flow rates were filled with cellular layers. All cellular layers at flow rate of 3 mL/min were incompact, but that at 9 mL/min were compact; at flow rate of 6 mL/min, the cellular layers were either compact or incompact. Real-time PCR revealed that after perfusion culture for 15 days, the mRNA expression of osteobalstic genes including ALP and OP, were enhanced significantly at flow rate of 6 and 9 mL/min as compared to that at 3 mL/min (P<0.01); however, the 9 mL/min group presented the higher OC expression than 3 and 6 mL/min group (P<0.001). Conclusions At early stage of perfusion culture, the proliferation of hMSCs was promoted at flow rate of 9 mL/min, while at late stage, there was more viable cells in scaffolds at flow rate of 6 mL/min. The osteoblastic differentiation of hMSCs was facilitated with the increase of perfusion flow rate, which was attributed to the increased flow shear stress.
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<p><b>BACKGROUND</b>Determination of the proper orientation of the knee articular surface is required both for correction of knee malalignment by osteotomy and for correct component alignment in knee arthroplasty. We sought to determine whether the patients' sex and lower extremity alignment (hip-knee-ankle angle) affects proper knee realignment in osteotomy or component alignment in total knee arthroplasty.</p><p><b>METHODS</b>We examined 199 healthy adult knees with malalignment of < 5° to determine the mechanical medial distal femoral angle, mechanical medial proximal tibial angle, surgical transepicondylar axis angle, and discrepancies between bone-cut orientations of osteotomy or total knee arthroplasty and the joint line of the distal femoral condyles, posterior femoral condyles and proximal tibial plateaus, using a three-dimensional computed tomography model.</p><p><b>RESULTS</b>The mean mechanical medial distal femoral angle and mean mechanical medial proximal tibial angle were (94.4 ± 1.9)° and (87.6 ± 1.8)° respectively for women and (93.8 ± 2.0)° and (87.1 ± 1.4)° respectively for men. The surgical transepicondylar axis angle was (2.9 ± 1.6)° for women and (3.2 ± 1.7)° for men. Independent of sex, the hip-knee-ankle angle was closely related to the mechanical medial distal femoral angle and mechanical medial proximal tibial angle, but not to the surgical transepicondylar axis angle. A slightly more valgus alignment of the knee and a more valgus angulation of the distal femoral joint line were found in women, whereas a more varus angulation of the proximal tibial joint line was found in men. Sex had the greatest effect on knee joint line orientation when the lower extremity was valgus in alignment.</p><p><b>CONCLUSIONS</b>A more valgus femoral joint line can be expected in women and in persons with valgus lower extremity alignment; a more varus tibial joint line can be found in men and in persons with varus lower extremity alignment.</p>