Objective. The purpose of this study was to compare the proximal femoral morphology between normal Chinese and Caucasian populations by 3D analysis derived from CT data. Materials and Methods. 141 anonymous Chinese femoral CT scans (71 male and 70 female) with mean age of 60.1years (range 20–93) and 508 anonymous Caucasian left femoral CT scans (with mean age of 64.8years (range 20–93). The CT scans were segmented and converted to virtual bones using custom CT analytical software. (SOMA™ V.4.0) Femoral Head Offset (FHO) and Femoral Head Position (FHP) were measured from head center to proximal canal central axis and to calcar or 20mm above Lesser Trochanter (LT) respectively. The Femoral neck Anteversion (FA) and Caput-Collum-Diaphyseal (CCD) angles were also measured. The Medial Lateral Widths(MLW. n. ) of femoral canal were measured at 0, -10, LT, -30, -40, -60, -70 and -100mm levels from calcar. Anterior Posterior Widths (APW. n. ) were measured at 0, -60 and -100mm levels. The Flare Index (FI) was derived from the ratio of widths at 0 and -60mmor FI=W. 0. /W. −60. All measurements were performed in the same settings for both populations. The comparison was analyzed by Student T test. P<0.05 was considered significant. Results. The average FHO and FHP of Chinese were 38.4mm and 25.2mm and were both shorter than 42.1mm and 29.7mm of Caucasian's, P=2.3E-15 and P=1.7E-10. (Figure 1) CCD angle was 130.3° comparing to 127.7° of Caucasian P=1.5E-05. Chinese FA angle was 15.6° and Caucasian's was 14.7°, P=0.31. The average MLW. 1-8. were 43.1, 34.6, 28.5, 23.8, 20.6, 17, 16.2 and 14.4mm for Chinese and 43.7, 35.0, 28.7, 24.0, 20.6, 16.7, 15.7 and 13.5mm for Caucasian. P=9.4E-02, .32, .47, .50, .93, .20, .02 and 1.7E-05 respectively. (Figure 2) The average APW. 1-3. were 35.9, 15.5 and 13.7mm for Chinese and 43.7, 15.2 and 12.5mm for Caucasian. P=4E-62, 0.11 and 7.4E-10. (Figure 3) The total medial/lateral and medial/center FI were 2.5 and 2.8 for Chinese, 2.6 and 2.9 for Caucasian. P=.004 and 4.5E-06. The total anterior/posterior and anterior/center FI were 2.3 and 2.6 for Chinese, 2.9 and 2.5 for Caucasian. P=5.3E-61 and 8.5E-04. Conclusion and Discussion. Chinese had significantly lower FHO, FHP, APW. calcar. , FI. medial, M-L. and FI. A-P. ; significantly higher CCD angle and MLW. isthmus. , APW. isthmus. and FI. anterior. than that of Caucasian population. There were no significant differences in FA and MLW from 10mm above to 50mm bellow LT. The average reduction of 3.7mm in FHO and 4.5mm in FHP for Chinese suggests a necessary adjustment of femoral implant neck length designed for Caucasian population. Due to the findings of the similarity in MLW and dissimilarity in APW, the study suggested the M-L fitting stem will fit well for both populations

Introduction. One of the objectives of total hip arthroplasty is to restore femoral and acetabular combined anteversion. It is desirable to reproduce both femoral and acetabular antevesions to maximize the acetabular cup fixation coverage and hip joint stability. Studies investigated the resultant of implanted femoral stem anteversion in western populations showed that the implanted femoral stems had only a small portion can meet the desirable femoral anteversion angle. 1. , and anteversion angle increases after the implantation of an anatomical femoral stem with anteverted stem neck comparing to anatomical femoral neck. 2. The purpose of this study was to anatomically measure the anteversion angular difference between metaphyseal long axis and femoral neck in normal Chinese population. The metaphyseal long axis represents the coronal fixation plane of modern cementless medial-lateral cortical fitting taper stem. This angular difference or torsion Δ angle provides the estimation of how much the neck antevertion angle of femoral stem would be needed to match for desirable anatomical femoral neck version. Methods. 140 (77 male and 63 female) anonymous normal adult Chinese CT data with average age of 54.6 (male 54.6, female 54.5, P=0.95) were segmented and reconstructed to 3D models in Trauson Orthopeadic Modeling and Analytics (TOMA) program. Femoral head center, femoral neck axis and center point of diaphyseal canal 100mm bellow calcar formed the femoral neck plane. The metaphyseal stem implantation plane was determined by the center point of medial calcar, proximal canal central axis formed by femoral neck plane and the center point of diaphyseal canal 100mm bellow calcar. [Fig. 1] The angle between two planes was the torsion Δ angle between femoral placement plane and anatomical femoral neck. [Fig. 2] The torsion Δ angles were measured for all 140 cases. The traditional anteversion angle for anatomical femoral neck was also measured by Murphy's method. Student T test was perform to compare the angles for male and female. The 98% confidence level was assumed. Results. The average torsion Δ angle for whole population was 4.9°(0.04°-15.6°), SD=3.52°, male: 4.6° (0.42°-13.9°), SD=3.09°; female: 5.3° (0.04°-15.6°), SD=3.98°. There was no statistical significant difference between genders. P=0.28. All metaphyseal stem placement planes were less anteverted than anatomical femoral neck plane. [Fig. 3] The average anatomical femoral neck anteversion angle for total population was 18.6° (0.27°-42.6°), SD=7.54°; male: 18.6° (0.27°-32.9°), SD=7.37°; female: 18.7° (1.74°-42.6°), SD=7.81°. There was no statistical significance between male and female P=0.92. Only 26% of study population or 37 cases with unadjusted implant neck version had normal anteversion angle of 10°-15° (Tönnis). Discussion. The study suggested femoral stem neck anteversion angle adjustments up to 11° was necessary to match anatomical femoral neck for 94% of cases in Chinese population. And the adjustments of 0°-7° represented the 76% majority of population. This finding was in agreement with the published data in western population. 2. . Significance. Variable femoral stem neck anteversion angles up to 11° are necessary to reproduce the anatomical anteversions for 94% of normal Chinese population. For any figures or tables, please contact the authors directly

Aim. Cyclooxygenase-2 (COX-2) enzyme is one of the major mediators during inflammation reactions, and COX-2 gene polymorphisms of rs20417 and rs689466 have been reported to be associated with several inflammatory diseases. However, potential links between the two polymorphisms and risk of developing post-traumatic osteomyelitis remain unclear. The present study aimed to investigate associations between the rs20417 and rs689466 polymorphisms and susceptibility to post-traumatic osteomyelitis in Chinese population. Methods. A total of 189 patients with definite diagnosis of post-traumatic osteomyelitis and 220 healthy controls were genotyped for rs20417 and rs689466 using the genotyping method*. Chi-square test was used to compare differences of genotype distributions as well as outcomes of five different genetic models between the two groups. Results. Significant association was found between rs689466 and post-traumatic osteomyelitis by recessive model (GG vs. AA + AG) (OR = 1.74, 95% CI: 1.098–2.755, P =0.018). Although no statistical differences were identified of rs689466 between the two groups by allele model (P = .098) or homozygous model (P = 0.084), outcomes revealed a tendency that allele G may be a risk factor and people of GG genotype may be in a higher risk to develop post-traumatic osteomyelitis in Chinese population. However, no significant link was found between rs20417 and susceptibility to post-traumatic osteomyelitis in this Chinese cohort. Conclusions. To our knowledge, we reported for the first time that COX-2 gene polymorphism rs689466 may contribute to the increased susceptibility to post-traumatic osteomyelitis in Chinese population. *SNaPshot®

INTRODUCTION:. Successful tibial component placement during total knee arthroplasty (TKA) entails accurate rotational alignment, minimal overhang, and good bone coverage, each of which can be facilitated with a tibial component that matches the resected tibial surface. Previous studies investigated bony coverage of multiple tibial component families on digitized resections. However, these studies were based on manual placement of the component that may lead to variability in overhang and rotational alignment. An automated simulation that follows a consistent algorithm for tibial component placement is desirable in order to facilitate direct comparison between tibia component designs. A simulation has been developed and applied to quantify tibial coverage in multiple ethnicities, including Japanese, Indian, and Caucasian. Here, this approach is taken to evaluate tibial coverage of five contemporary tibial designs in Chinese subjects. METHODS:. Digital models of 100 healthy Chinese tibiae (50 male, 50 female; age 68 ± 3 years; stature 1.65 ± 0.10 m) were virtually resected at 5° posterior slope referencing the anterior border of the proximal tibia, 0° varus/valgus rotation referencing the tibial mechanical axis, and 8 mm off the unaffected plateau (reflecting a 10 mm surgical cut, assuming a cartilage thickness of 2 mm). Neutral internal/external (I/E) alignment axis was derived from the medial third of the tubercle and the PCL attachment site. Five commercial tibial designs (Design A, Deluxe™, Montagne, Beijing, China; Designs B-E contemporary market-established symmetric designs from four US manufacturers) were virtually placed on the resected tibiae following an automated algorithm, which maximizes component size while ensuring proper rotational alignment (within 5° I/E) and minimizing overhang (<1 mm in zones 1–4, Fig 1). Tibial coverage (posterior notch excluded, zone 5 in Fig 1) and distance from the component to the exterior cortex of the tibia in four clinically relevant anatomical zones (anterior medial, anterior lateral, posterior medial, and posterior lateral, zones 1–4, Fig 1) were calculated. Statistical significance was defined at p < 0.05. RESULTS:. Coverage across designs varied between 75% and 96%. All five designs showed comparable means and standard deviations in tibial coverage (Fig. 2). Although statistically higher coverage was found in Designs D-E than Designs A-C (p < 0.04), the difference in means (86–87% for Designs A-C; 88% for both Designs D-E) was clinically not meaningful (Fig. 2). Design A was found to be slightly (0.67 mm, p = 0.02) farther away from the cortex than Design E in the anterior medial zone; no other significant differences were found for distance to cortex between any of the component designs in any of the anatomical zones (Fig. 3). DISCUSSION:. The data suggests comparable tibial coverage, which may reflect the likelihood for component subsidence clinically, is expected between the six contemporay design investigtated when implanted into Chinese patients. Though subsidence is multifactorial, and is dependent on aspects of implant design and surgical technique beyond just tibial tray shape, these results nevertheless provide initial indicators on the expected rate of subsidence or overhang in Chinese patients for Design A relative to the more established Designs B-E

Background. Recent anthropometric studies have suggested that current design of total knee arthroplasty (TKA) does not cater to racial anthropometric differences. The purpose of this study was to investigate the exact sizing and rotational landmarks of the distal femur collected from a large group of healthy Southern Chinese using three dimensional computer tomographic measurements, and then compare these measurements to the known dimensions from Caucasian populations. Methods. This study evaluated distal femoral geometry in 125 healthy Southern Chinese, included 58 women (106 knees) and 67 men (134 knees) with a mean age of 35.2±8.11 years, a mean height of 165.5±7.94 cm, and a mean weight of 61.7±9.56 kg. The width of the articular surface as projected onto the transepicondylar line(ML), anteroposterior dimension (AP), the dimensions from medial/lateral epicondyle to posterior condylar (MEP/LEP)were measured. A characterization of the aspect ratio (ML/AP) was made for distal femur[Fig. 1]. The angles between the tangent line of the posterior condylar surfaces, the Whiteside line, the transepicondylar line, and the trochlear line were measured. The sulcus angle and hip center-femoral shaft angle were also measured. Known dimensions from Caucasian populations were compared with the morphologic data collected in this study[Fig. 2]. In analyzing the data, best-fit lines were calculated with use of least-squares regression. The dimensions are summarized as the mean and standard deviation. The differences of rotational landmarks and sizing between the Southern Chinese and Caucasians were assessed with use of the Student t test. A p value of <0.05 indicated a significant effect. Results. Within the Southern Chineses population, males had larger ML and AP values than females (ML: 70.38±3.09 vs. 62.09±2.52mm, P<0.001; AP: 63.68±2.82 vs. 57.83±2.91mm, P<0.001). The results also showed that Southern Chinese knees were generally smaller than Caucasian (ML: 67.27±4.95 vs. 76.8±7.2mm, P<0.001). The femoral aspect ratio of Southern Chinese was significantly smaller than Caucasian (1.09±0.04 vs. 1.28±0.06, P<0.001). In addition, we found a gradual decrease in the aspect ratio corresponding to an increase in anteroposterior dimension in the distal femur of Southern Chinese, as seen in most other studies. The transepicondylar axis was found to be a reliable landmark to properly rotate the femoral component, so we used the femoral condylar MEP and LEP evaluate posterior condylar offset, the values were respectively 28.62±2.18mm and 22.50±2.19mm. From this study, most of the angles were different from Caucasian. Anteroposterior line minus epicondylar line angle was 90.14±1.30° (Caucasian 90.33±2.44°, P>0.05), anteroposterior line minus posterior condylar line angle was 83.18±1.94° (Caucasian 86.82±2.71°, P<0.001), epicondylar line minus posterior condylar line angle was 7.00±1.70° (Caucasian 3.60±2.02°, P<0.001), trochleoepicondylar angle was 12.45±2.34°(Caucasian 4.95±2.15°, P<0.001), sulcus angle was 147.40±4.69° (Caucasian 139.6±6.96°, P<0.001). The angle between mechanical and anatomic axis of the femur was 5.92±0.47°(Caucasian 6.33±2.42°, P<0.001). Conclusion. Because dimensions of the distal femur and the aspect ratio tend to be smaller in Southern Chinese populations, whereas sulcus angles tend to be larger, designs for knee implants should be modified to improve the outcome of surgical treatment in this population. The Larger epicondylar line minus posterior condylar line angles, and the smaller angle between mechanical and anatomic axis seen in Southern Chinese populations also requires us to pay particular attention to surgical technique, in order to ensure patient safety

Aim. Previous studies had indicated that interleukin-1 beta (IL-1β) gene single nucleotide polymorphisms (SNPs) associate with different inflammatory diseases. However, potential links between these polymorphisms and susceptibility to extremity chronic osteomyelitis (COM) in Chinese population remain unclear. This study aimed to investigate relationships between IL-1β gene polymorphisms (rs16944, rs1143627, rs1143634 and rs2853550) and the risk of developing extremity COM in Chinese population. Method. Altogether 233 extremity COM patients and 200 healthy controls were genotyped for the four tag SNPs of the IL-1β gene using the SNapShot genotyping method. Comparisons were performed regarding genotype distribution, mutant allele frequency and four genetic models (dominant, recessive, homozygous and heterozygous models) of the 4 SNPs between the two groups. Results. Significant associations were identified between rs16944 polymorphism and the risk of developing COM by dominant model (P = 0.026, OR = 1.698, 95% CI 1.065–2.707) and heterozygous model (P = 0.030, OR = 1.733, 95% CI 1.055 – 2.847). Although no statistical differences were found of rs1143627 polymorphism between the two groups, there existed a trend that rs1143627 may be linked to an elevated risk of developing COM by outcomes of dominant (P = 0.061), homozygous (P = 0.080) and heterozygous (P = 0.095) models. However, no statistical correlations were found between rs1143634 and rs2853550 polymorphisms and susceptibility to COM in Chinese population. Conclusions. To our knowledge, we reported for the first time that IL-1β gene rs16944 polymorphism may contribute to the increased susceptibility to extremity COM in Chinese population, with genotype of AG as a risk factor

With the increasing use of 3D medical imaging, it is possible to analyze 3D patient anatomy to extract features, trends and population specific shape information. This is applied to the development of ‘standard implants’ targeted to specific population groups. INTRODUCTION. Human beings are diverse in their physical makeup while implants are often designed based on some key measurements taken from the literature or a limited sampling of patient data. The different implant sizes are often scaled versions of the ‘average’ implant, although in reality, the shape of anatomy changes as a function of the size of patient. The implant designs are often developed based on a certain demographic and ethnicity and then, simply applied to others, which can result in poor design fitment [1]. Today, with the increasing use of 3D medical imaging (e.g. CT or MRI), it is possible to analyze 3D patient anatomy to extract features, trends and population specific shape information. This can be applied to the development of new ‘standard implants’ targeted to a specific population group [2]. PATIENTS & METHODS. Our population analysis was performed by creating a Statistical Shape Model (SSM) [3] of the dataset. In this study, 40 full Chinese cadaver femurs and 100 full Caucasian cadaver femurs were segmented from CT scans using Mimics®. Two different SSMs, specific to each population, were built using in-house software tools. These SSMs were validated using leave-one-out experiments, and then analyzed and compared in order to enhance the two population shape differences. RESULTS. An SSM is typically represented by an average model and a few independent modes of variation that capture most of the inherent variations in the data. Based on these main modes of variations, the shape features, e.g. length, thickness, curvature neck angle and femoral version, presenting largest variations were determined, and correlations between these features were calculated. Figure 1 represents the Caucasian and Chinese average models, and shows that while the length of these two models was significantly different, the AP and ML dimensions were similar, indicating a difference of morphology (other than a scaling) between the two populations. Figure 2 represents the first mode of variation that illustrates the variation of Chinese femur shape with size. As an example, the neck angle increases of 26° with an increase of 139 mm in femur length, indicative of the effect of changes in loading conditions on geometry as a function of size. CONCLUSION. The advantage of using more advanced statistical analyses is that the 3D data are probed in an unbiased fashion, allowing the most important parameters of variation to be determined. These analyses are thus particularly effective to compare different populations, to evaluate how well existing implant designs fit specific populations, and to highlight the design parameters that need to be adapted for good fitment of specific populations

Background. The purpose of this study was to investigate the morphology characteristic of proximal femur of Chinese people. 170 healthy Southern Chinese hips being measured using 3D computer tomographic, in order to improve prosthesis design and preoperation plan of total hip arthroplasty. Methods. This study measured proximal femoral geometry in 85 healthy Southern Chinese, included 39 women (78 hips) and 46 men (92 hips) (mean age: 33.9 y, mean height: 164.7 cm, mean weight 59.9 kg). Medullary canal morphology measurements, include: the position of isthmus, medial-lateral(ML) and anteroposterior(AP) medullary canal diameter of isthmus and 20 mm, 10 mm, 0 mm, −20 mm, −160 mm, −200 mm upon less trochanter(LT) (medullary canal height, MCH), canal flare index(CFI), aspect ratio(ML/AP), epiphysis-shaft angel (ES angel) (a posterior bow in the metapysis in lateral view). Exterior morphology measurements include: femoral head offset, ML and UD diameter, femoral head position(FHP) from LT, height of the femoral head center from the tip of the great trochanter(GT)(FHCH), femoral neck and head anteversion angle, femoral neck-shaft angle, neck length, neck width, intertrochanteric length (Fig 1, Fig 2). And then we use student's t–test to compare means, linear regression and correlation to analysis these data's relationship, p value <0.05 indicated a significant effect. Results. Males had a larger diameter of medullary canal than females (Fig3). The isthmus position is 117.69±11.95 VS 111.14±13.01 mm (male VS female) (p=0.070) below less trochanter, and it's ML diameter is 9.57±1.52 VS 8.88±1.80 mm (p=0.151), AP diameter is 11.85±2.68 VS 10.53±2.49 mm (p=0.073). The mean medullary canal aspect ratio is 1.38±0.20, 1.30±0.12, 1.15±0.13, 1.03±0.09, 0.84±0.11, 0.87±.011 and 1.04±0.17 respectively at 20 mm, 10 mm, 0 mm, −20 mm, isthmus, −160 mm, −200 mm upon less trochanter. The medullary canal diameter were positively correlated to MCH (R=0.793, p=0.000 VS R=0.790, p=0.000) (ML VS AP). The ES angle is 156.78±4.29 VS 157.90±4.90 degree (p=0.395) (male VS female). The femoral head offset is 39.14±3.87 VS 35.86±3.68 mm (p=0.003), femoral neck, head and comprehensive anteversion angle is 18.34±8.07 VS 17.9±10.64 degree (p=0.872), −2.61±6.47 VS −2.36±5.55 degree (p=0.881) and 15.73±7.26 VS 15.54±8.54 degree (p=0.934). FHP is 51.67±7.82 VS 45.37±5.59 mm (p=0.001), FHCH is −6.77±5.58 VS −6.13±4.87 mm (p=0.665), femoral head diameter is (ML: 43.94±2.62 VS 39.25±2.66 mm (p=0.000), UD: 45.16±1.96 VS 41.26±2.23 mm (p=0.000)). Femoral neck-shaft is 130.10±4.57 VS 130.83±6.40 degree (p=0.652), femoral neck length and width is 21.84±4.87 VS 20.69±3.41 mm (p=0.322) and 34.75±2.26 VS 31.80±2.63 mm (p=0.000), femoral intertrochanteric length is 68.11±4.72 VS 61.27±5.04 mm (p=0.000), most of these dimensions were positively correlated to height. Conclusion. Males had a larger medullary canal than females, the long diameter of medullary canal is transverse at proximal femoral, and it gradually become longitudinal when move to isthmus then become transverse again below isthmus, this may offer valuable revelation for our anti-rotation design and better distal fixation. The medullary canal diameter were positively correlated to MCH. 71% (121 hips) femoral heads had a retroversion angle compare to femoral neck. The femoral head rotation center is below the tip of the GT rather than on the same level that may suggested a shorter neck implants for Southern Chinese patients

Aim. Previous studies have indicated that TNF-α and lymphotoxin-α (LTA) gene polymorphisms associate with the development of several different inflammatory diseases. However, potential associations of such gene polymorphisms with the susceptibility to extremity chronic osteomyelitis remain unknown. This study aimed to investigate potential links between TNF-α gene polymorphisms (rs1800629, rs361525, rs1799964, rs1800630, rs1799724 and rs1800750) and LTA gene polymorphism (rs909253) and the risk of developing extremity chronic osteomyelitis in Chinese population. Method. A total of 233 patients with extremity chronic osteomyelitis and 200 healthy controls were genotyped for the above 7 polymorphisms of TNF-α and LTA genes using the genotyping method*. Results. Significant difference was found regarding the genotype distribution of rs909253 between patients and healthy controls (P = 0.002). The mutant allele C frequency of rs909253 in patient group was significantly higher than that in control group (P = 0.001). Significant associations were identified between rs909253 and the risk of developing chronic osteomyelitis by dominant model (P = 0.040), recessive model (P = 0.002) and homozygous model (P = 0.001). Additionally, the mutant allele T frequency in rs1799964 in patient group was significantly higher than that in control group (P = 0.035). Significant link was found between rs1799964 and susceptibility to chronic osteomyelitis by recessive model (P = 0.048). However, no significant outcomes were identified regarding other TNF-α gene polymorphisms between the two groups. Conclusions. The present study demonstrated that rs909253 and rs1799964 polymorphisms may associate with the risk of developing chronic osteomyelitis in Chinese population. *SNaPshot

Background. Recent anthropometric studies have suggested that current design of total knee arthroplasty (TKA) does not cater to racial anthropometric differences. The purpose of this study was to investigate the exact sizing and rotational landmarks of the distal femur collected and its gender differences from a large group of healthy Southern Chinese using 3D-CT measurements, and then compare these measurements to the five total knee prostheses conventionally used in China. Methods. This study evaluated distal femoral geometry in 85 healthy Southern Chinese, included 39 females (78 knees) and 46 males (92 knees) with a mean age of 33.9 years，a mean height of 164.7 cm and a mean weight of 59.9 kg. The width of the articular surface as projected onto the transepicondylar line(ML), anteroposterior dimension (AP), the dimensions from medial/lateral epicondyle to posterior condylar (MEP/LEP) were measured. A characterization of the aspect ratio (ML/AP) was made for distal femur. The angles between the tangent line of the posterior condylar surfaces, the Whiteside line, the transepicondylar line, and the trochlear line were measured. The sulcus angle and hip center-femoral shaft angle were also measured [Fig. 1]. The data were compared with the five total knee prostheses conventionally used in China. In analyzing the data, best-fit lines were calculated with use of least-squares regression. The dimensions are summarized as the mean and standard deviation. Comparisons of dimensions between males and females were made with use of the two-sample t test. A p value of <0.05 indicated a significant effect. Results. Within the population, males had larger ML, AP values and aspect ratio than females (ML: 70.44±3.04 vs. 61.40±2.62 mm, P<0.001; AP: 62.26±2.93 vs. 56.49±2.88 mm, P<0.001; 1.06±0.05 vs. 1.11±0.03, P<0.001). In addition, we found a gradual decrease in the aspect ratio corresponding to an increase in AP dimension, as seen in other studies. The transepicondylar axis was a reliable landmark to properly rotate the femoral component, so we used the MEP and LEP evaluate posterior condylar offset, the values were respectively 28.90±3.00 mm and 22.73±2.67 mm. However, most angles were almost the same between males and females. To evaluate the suitability shape of the femoral components currently used in China, we drawed and calculated best-fit lines for the AP, ML dimensions and aspect ratios of the femur and the five prostheses. For females, there was a significant association between the prostheses size and the amount of overhang, the femoral prostheses for females tended to be too large for a given AP dimension, with larger sizes having more overhang, especially in ML dimensions. In males, the morphologic data tended to be bigger than the prosthetic designs in the ML dimension for a given AP dimension, the femoral aspect ratio was higher for smaller knees and proportionally lower for larger knees[Fig. 2, 3]. Conclusion. Because dimensions of the distal femur and the aspect ratio tend to be smaller in Southern Chinese populations, whereas sulcus angles tend to be larger, designs for knee implants should be modified to improve the outcome of surgical treatment in this population

An increasing number of patients with hepatitis B virus (HBV) infection are progressing in age and are undergoing total joint arthroplasty (TJA) surgery in China. Less attention is provided to the special populations. This study aimed to evaluate the effect of HBV on TJAs. We retrospectively reviewed all patients who met the inclusion of undergoing elective primary hip and knee arthroplasties from 2013– 2016. Non-hepatitis B cohort was built to match the case cohort to identify whether HBV infection was a risk factor associated with postoperative complications. A total number of 197 patients who underwent primary TJAs were involved in the study, including 49 patients with hepatitis B and 147 non-hepatitis B subjects. Among all the patients with TJAs, we obtained a 5.5% HBV infection rate for the first time. Compared with patients without hepatitis B, patients with hepatitis B had higher rates (P < 0.01) of total complications (10.2% compared to 4.7%), surgery-related complications (6.1% compared to 3.4%), and general medical complications (4.1% compared to 1.3%) than the non-hepatitis B group. Patients with hepatitis B infection had a 21% increased risk (95% CI, 0.97–1.46; p < 0.01) of total complication compared with non-hepatitis B group. Similar results were obtained for medical and surgical complications. HBV infection had a 31% increased risk (95% CI, 1.02–1.62; p < 0.01) for medical complication and 18% risk (95% CI, 0.95–1.42; p < 0.01) for surgical complication. In the subgroup analysis, no difference was found between the surgical methods and sex, whereas a significant difference of CRP change level (P < 0.01) was found between HBV group and the matched group in the clinical laboratory values. This is the first study of patients with hepatitis B undergoing primary THA or TKA and demonstrates an increased risk of multiple perioperative complications in a Chinese population. In consideration of the large population of HBV infection in China, more attention should be provided to patients with HBV infection who need to undergo TJAs

In patients with shoulder arthritis, the ability to accurately determine glenoid morphological alterations affects the outcomes of shoulder arthroplasty surgery significantly. This study was conducted to determine whether there is a correlation between scapular and glenoid morphometric components. Existence of such a correlation may help surgeons accurately estimate glenoid bone loss during pre-operative planning. The dimensions and geometric relationships of the scapula, scapula apophysis and glenoid were assessed using CT scan images of 37 South African and 40 Chinese cadavers. Various anatomical landmarks were marked on the 77 scapulae and a custom script was developed to perform the measurements. Intra-cohort correlation and inter-cohort differences were statistically analysed using IBM SPSS v28. The condition for statistical significance was p<0.05. The glenoid width and height were found to be significantly (p<0.05) correlated with superior glenoid to acromion tip distance, scapula height, acromion tip to acromion angle distance, acromion width, scapula width, and coracoid width, in both the cohorts. While anterior glenoid to coracoid tip distance was found to be significantly correlated to glenoid height and width in the South African cohort, it was only significantly correlated to glenoid height in the Chinese cohort. Significant (p<0.05) inter-cohort differences were observed for coracoid height, coracoid width, glenoid width, scapula width, superior glenoid to acromion tip distance, and anterior glenoid to coracoid tip distance. This study found correlations between the scapula apophyseal and glenoid measurements in the population groups studied. These morphometric correlations can be used to estimate the quantity of bone loss in shoulder arthroplasty patients

Lung cancer is the most common cancer diagnosed, the leading cause of cancer-related deaths, and bone metastases occurs in 20–40% of lung cancer patients. They often present symptomatically with pain or skeletal related events (SREs), which are independently associated with decreased survival. Bone modifying agents (BMAs) such as Denosumab or bisphosphonates are routinely used, however no specific guidelines exist from the National Comprehensive Cancer Center or the European Society of Medical Oncologists. Perhaps preventing the formation of guidelines is the lack of a high-quality quantitative synthesis of randomized controlled trial (RCT) data to determine the optimal treatment for the patient important outcomes of 1) Overall survival (OS), 2) Time to SRE, 3) SRE incidence, and 4) Pain Resolution. The objective of this study was to perform the first systematic review and network meta-analysis (NMA) to assess the best BMA for treatment of metastatic lung cancer to bone. We conducted our study in accordance to the PRISMA protocol. We performed a librarian assisted search of MEDLINE, PubMed, EMBASE, and Cochrane Library and Chinese databases including CNKI and Wanfang Data. We included studies that are RCTs reporting outcomes specifically for lung cancer patients treated with a bisphosphonate or Denosumab. Screening, data extraction, risk of bias and GRADE were performed in duplicate. The NMA was performed using a Bayesian probability model with R. Results are reported as relative risks, odds ratios or mean differences, and the I2 value is reported for heterogeneity. We assessed all included articles for risk of bias and applied the novel GRADE framework for NMAs to rate the quality of evidence supporting each outcome. We included 132 RCTs comprising 11,161 patients with skeletal metastases from lung cancer. For OS, denosumab was ranked above zoledronic acid (ZA) and estimated to confer an average of 3.7 months (95%CI: −0.5 – 7.6) increased survival compared to untreated patients. For time to SRE, denosumab was ranked first with an average of 9.1 additional SRE-free months (95%CI: 4.0 – 14.0) compared to untreated patients, while ZA conferred an additional 4.8 SRE-free months (2.4 – 7.0). Patients treated with the combination of Ibandronate and systemic therapy were 2.3 times (95%CI: 1.7 – 3.2) more likely to obtain successful pain resolution, compared to untreated. Meta-regression showed no effect of heterogeneity length of follow-up or pain scales on the observed treatment effects. Heterogeneity in the network was considered moderate for overall survival and time to SRE, mild for SRE incidence, and low for pain resolution. While a generally high risk of bias was observed across studies, whether they were from Western or Chinese databases. The overall GRADE for the evidence underlying our results is High for Pain control and SRE incidence, and Moderate for OS and time to SRE. This study represents the most comprehensive synthesis of the best available evidence guiding pharmacological treatment of bone metastases from lung cancer. Denosumab is ranked above ZA for both overall survival and time to SRE, but both treatments are superior to no treatment. ZA was first among all bisphosphonates assessed for odds of reducing SRE incidence, while the combination of Ibandronate and radionuclide therapy was most effective at significantly reducing pain from metastases. Clinicians and policy makers may use this synthesis of all available RCT data as support for the use of a BMA in MBD for lung cancer

Introduction & aims. Different racial groups show variations in femoral morphometry. Femoral anteroposterior measurement and mediolateral measurement are key variables in designing femoral implant for TKR. Their aspect ratio determines the shape and mediolateral sizing for the proper patellofemoral tracking and uniform stress distribution over the resected distal femoral surface. Method. We reviewed the current literature in December 2013 in common medical databases including the Cochrane Library, PubMed and Medline. Keywords included combinations of: Anthropometry, Knee, Arthroplasty, Femur, Morphometry, Geometry. We selected papers including femoral morphometric data collected from populations of different ethnic origins. Papers covered populations in the USA, China, Germany, Thailand, Korea, India, Japan and Malaysia. Results. We have analysed femoral morphometry variables among different ethnic groups from the available data. Gross size of the resected femur can be defined in terms of antero-posterior (AP) and medio-lateral (ML) dimensions, an in the aspect ratio of femoral medio-lateral to femoral antero-posterior dimensions (fML/fAP). The Korean population showed the least value of fAP among all the groups, followed by Thai, Japanese, Indian, Malaysian and Chinese showing the increasing order among the sub-groups of Asian Population. American population shows the next higher fAP measurements from Asian population. German follows, and Arab quantify the largest value of this femoral anthropometric variable. fML varies by huge difference among male and female data in all populations. Thai, Indian, Malaysian, Arab, Japanese, Korean, German, Chinese and American; this sequence is the increasing order of fML. More trapezoid-shaped and narrower ML, this variation in female group leads to over-hang the implant for a given fAP. Generally, the aspect ratios are measured higher in these smaller female knees, and lower in larger male knees. Conclusions. Anthropometric data measuring distal femoral segment in different ethnic groups shows that the Asian population requires custom-fit implant design based on the morphological data. It would be more appropriate to introduce several medio-lateral options in sizing the implant for given antero-posterior dimensions

Aims. The incidence of thigh pain with the short stem varies widely across different studies. We aimed to evaluate the incidence and characteristics of post-operative thigh pain after using a particular bladed short stem and its potential risk factors. Patients and Methods. We respectively reviewed 199 consecutive patients who underwent unilateral total hip replacement using the Tri-lock stem from 2013–2016, of which 168 patients were successfully followed up with minimum two year clinical follow-up. All information about thigh pain and pre- and postoperative HHS score were gathered and all preoperative and immediate postoperative radiographs were available for review. Any complications were recorded. Results. Of the 168 patients, 34 (20.2%) patients reported thigh pain at a mean 3.1 years after surgery. Of these, 2 (5.9%) reported severe pain (NRS 5 or more). The pain was persistent (from surgery to final follow-up) in 13 patients (38.2%) and subsided within 2 years in 10 cases (29.4%). The most common site of pain was the lateral thigh (70.6%). The HHS improved from a mean 54.2 points preoperatively to 79.8 postoperatively. In 123 cases with radiographs at more than 2 years follow-up, all femoral stems were well-fixed and no revision surgery was needed at the latest. BMI and CFI were found to be independent risk factors for thigh pain after using this particular stem component. Conclusions. The incidence of thigh pain in Chinese THA patients with a bladed short stem component design is as high as 20%. Among them, nearly 40% will have some disruption in sleep or daily life. More than one-third of the cases of thigh pain were persistent. A larger BMI and patients with a funnel-type morphology of the femoral canal are independent risk factors for thigh pain in the setting of this particular stem component

Introduction. A good anatomic fit of a Total Knee Arthroplasty is crucial to a good clinical outcome. The big variability of anatomies in the Asian and Caucasian populations makes it very challenging to define a design that optimally fits both populations. Statistical Shape Models (SSMs) are a valuable tool to represent the morphology of a population. The question is how to use this tool in practice to evaluate the morphologic fit of modern knee designs. The goal of our study was to define a set of bone geometries based on SSMs that well represent both the Caucasian and the Asian populations. Methods. A Statistical Shape Model (SSM) was built and validated for each population: the Caucasian Model is based on 120 CT scans from Russian, French, German and Australian patients. The Asian Model is based on 80 CT scans from Japanese and Chinese patients. We defined 7 Caucasian and 5 Asian bone models by using mode 1 of the SSM. We measured the antero-posterior (AP) and medio-lateral (ML) dimensions of the distal femur on all anatomies (input models and generated models) to check that those bone models well represent the studied population. In order to cover the whole population, 10 additional bone models were generated by using an optimization algorithm. First, a combined Asian-Caucasian SSM was generated of 92 patients, equally balanced between male and female, Caucasian and Asian. 10 AP/ML dimensions were defined to obtain a good coverage of the population. For a given AP/ML dimension, Markov chain Monte Carlo sampler was used to find the most average shape with AP/ML dimensions as close as possible to the target dimensions. The difference of the AP/ML dimensions of the generated models to the target dimensions was computed. A chi-squared distribution was used to assess how average the resulting shapes were compared to typical patient shapes. Results. The AP-ML dimensions of the 7 Caucasian bones and the 5 Asian bones well cover the range of the respective populations. For the Caucasian Femur, the AP/ML dimensions range from (53,6/64,9mm) for size 1 to (67,7/80,7mm) for size 7. For the Asian Femur, the AP/ML dimension range from (53,0/62,4mm) for size 1 to (60,5/72,4mm) for size 5. The dimensions of the 10 additionally generated bones differed in average (± 1 standard deviation) by 0,2±0,4mm in AP and 0,5±0,5mm in ML to the target dimensions. The maximal deviation was 0,9mm in AP and 1,0mm in ML. All 10 bones had a P-value of P < 10. -27. according to the chi-squared distribution. Conclusion. The proposed models of 7 Caucasian and 5 Asian bones well represent both populations. The 10 additional geometries enable to get a complete coverage of the population. Since they are very close to average, all these bone models provide more generalized reference shapes compared to individual patients. By performing a virtual implantation on those anatomies, the anatomical fit of implants to these populations can be evaluated. For any figures or tables, please contact authors directly

INTRODUCTION. Femur is one of the bones in humans that exhibit ethnic, racial, and gender difference. Several basic and clinical studies were conducted to explore these variations. Clinical anthropological studies have dealt with the compatibility of femoral prostheses and osteosythesis and materials with the femur. If there is a misalignment between the Total Knee Arthroplasy (TKA) femoral comportment installation position, Range of Motion (ROM) failure and several problems may arise. The aim of this study was to evaluate anterior bowing of the Japanese femur and to assess the adequacy of TKA femoral comportment installation position. METHODS. We analyzed 76 normal Japanese and 97 TKA patients. (June 2014-June 2015) The average age of the normal subjects was 62.0±20.90 (24–88) years old and the average of TKA subjects was 73.6±7.9 (53–89) years old. First we defined and measured the anterior curvature and the posterior condylar offset (PCO) in normal japanese femurs. Then in TKA patients we set the implant as same angle of the component. Third, we measured the post operative anterior curvature and PCO. Then calculated the anterior curvature difference and PCO differences and preformed statistical analysis with ROM. RESULTS SECTION. The average of anterior curvature in normal subjects was 7.87±6.60 degrees. Among 97 TKA patients, pre-operative anterior curvature was 7.58±0.16 degrees. Further, the angle of component which was set the post operatively was 7.32±0.25. The average of Anterior curvature difference and PCO differences had correlation with ROM. DISCUSSION. Gilbert reported that caucasian femurs are straight compared to asian femurs. Chinese and Japanese showed different anterior curvature because of different life style. The chalenges are when operating on different ethnic patients, Orthopedic Surgeons consider many factors. Previous studies yielded different suggestions for the ideal point of entry. We suggest difference between the curves of the femurs should be considered for TKA femoral comportment installation position. SIGNIFICANCE. 1)Our results gave an anatomical characteristics of Japanese femur. 2)These data will give clinical indication for TKA femoral comportment installation position

Introduction. Total knee arthroplasty (TKA) is an excellent treatment for end-stage osteoarthritis of the knee. In Asian countries, the number of TKA performed has rapidly increased, and is expected to continue so with its 4.4 billion population and increasing life expectancy. Asians' knees are known to be kinematically different to Caucasians after TKA. Controversy exists as to whether multi-radius (MR) or the newer single-radius (SR) TKA has superior outcome. Studies regarding this have been largely based on Caucasian data with few small sample Asian data. Methods. This is a retrospective analysis of prospectively collected institutional registry data between 2004 and 2015. Outcomes of 133 single-radius (SR) (Scorpio NRG, Stryker) and 363 multi-radius (MR) (Nexgen LPS, Zimmer) primary TKA for primary osteoarthritis were compared. All TKA was performed or directly supervised by the senior author. Range of motion (ROM), Oxford Knee Score (OKS), SF-36 physical component score (SF36-PCS), SF-36 mental component score (SF36-MCS), Knee Society Function Score (KS-FS) and Knee Score (KS-KS) were recorded preoperatively and at 2 years post-operation. Results. The mean age in both groups were similar at 66 ± 8 years (p=0.66). Both groups were in majority female (71% and 70% females in SR and MR respectively, p=0.10) and ethnic Chinese (79% and 84% in SR and MR respectively, p=0.53). The preoperative ROM and outcome scores in both groups were similar. MR-TKA achieved significantly greater improvement over 2 years in terms of ROM (7.5º ± 18.2º vs. 3.5º ± 19.3º, p=0.04), KS-KS (49.0 ± 20.9 vs. 42.7 ± 21.1, p=0.01), OKS (17.4 ± 18.4, p=0.03), and SF36-PCS (17.1 ± 12.5, p=0.02). At 2-years follow up, MR-TKA group fared slightly better for SF36-PCS (48 ± 10 vs. 46 ± 10, p=0.032), but the absolute difference was only 2 points. There were no significant differences between SR-TKA and MR-TKA for ROM (115º ± 16º vs. 117º ± 16º, p=0.218), KS-KS (81 ± 16 vs. 85 ± 12, p=0.795), KS-FS (74 ± 21 vs. 75 ± 20, p=0.627), OKS (20 ± 7 vs. 18 ± 6, p=0.099), and SF36-MCS (56 ± 10 vs. 55 ± 10, p=0.324). There were larger proportions of MR-TKA patients who achieved the minimum clinically important difference (MCID) for OKS (95% vs. 82%, p<0.001) and SF36-PCS (67% vs. 55%, p=0.011) at 2-years follow-up. Logistic regression, controlling for all preoperative variables, showed SR-TKA is less likely to achieve MCID for OKS with an odds ratio of 0.275 (95% confidence interval: 0.114 – 0.663, p=0.004), and SF36-PCS with an odds ration of 0.547 (0.316 – 0.946, p=0.031). Discussion and conclusion. SR-TKA and MR-TKA produced similar outcomes, in concordance with current literature. However, SR-TKA has lower odds of achieving MCID in OKS and SF36-PCS, possibly due to its smaller improvement in flexion over 2 years. This subtle difference has a greater impact in the context of Asian patients due to the cultural practice of kneeling and/or squating

Backgroud:. Periarticular multimodal drug injection (PMDI) during total knee arthroplasty (TKA) has been reported with promising effects, but some results still remain controversial. Therefore, we conducted a systematic review and meta-analysis based on randomized controlled trials (RCTs) to evaluate the efficiency and safety of PMDI technique in TKA. Methods:. We systematically conducted an electronic search in the databases of PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science (SCI), and the Chinese Biomedical Literature Database (CBM). Two independent reviewers completed data collection and assessment of methodological quality according to the Cochrane Handbook 5.1. The quality of evidence of outcomes was judged using GRADE criteria. Statistical analysis was performed using the RevMan 5.1 software. Results:. Ten studies including eight trials with 1216 TKAs in 835 patients met the inclusion criteria. The short-term results of meta-analysis showed that technique of PMDI in TKA was associated with significantly improved pain scores on the day of surgery and postoperative 1 day [MD = −1.07, 95% CI (−1.43, −0.71), p < 0.01], better straight leg raise[OR = 4.02, 95% CI (2.25, 7.18), p < 0.01], reduced narcotic consumption within postoperative 24 hours [MD = −4.83, 95% CI (−6.61, −3.05), p < 0.01], and less rates of nausea or vomiting, and rash or pruritus [OR = 0.34, 95% CI (0.22, 0.55), p < 0.01]. There were no statistically significant differences in operating time [MD = 0.17, 95% CI (−1.48, 1.82), p = 0.84], hospital stay [MD = −0.20, 95% CI (−1.18, 0.79), p = 0.70], wound complication [OR = 0.79, 95% CI (0.31, 2.04), p = 0.63] and deep vein thrombosis [OR = 0.87, 95% CI (0.42, 1.78), p = 0.69] between both groups. Conclusions:. Periarticular injection with multimodal drugs in TKA has significant short-term advantages in pain relief, functional recovery, and narcotic consumption with fewer rates of complications (nausea or vomiting and rash or pruritus). Further well-designed RCTs are still needed to investigate the long-term efficiency of PMDI in patients undergoing TKA

Aims

The COVID-19 pandemic drastically affected elective orthopaedic services globally as routine orthopaedic activity was largely halted to combat this global threat. Our institution (University College London Hospital, UK) previously showed that during the first peak, a large proportion of patients were hesitant to be listed for their elective lower limb procedure. The aim of this study is to assess if there is a patient perception change towards having elective surgery now that we have passed the peak of the second wave of the pandemic.