Aims

The purpose of this study was to evaluate the mid-term outcomes of autologous matrix-induced chondrogenesis (AMIC) for the treatment of larger cartilage lesions and deformity correction in hips suffering from symptomatic femoroacetabular impingement (FAI).

Aims

The aim of this investigation was to compare risk of infection in both cemented and uncemented hemiarthroplasty (HA) as well as in total hip arthroplasty (THA) following femoral neck fracture.

We investigated factors associated with postoperative lipiduria and hypoxemia in patients undergoing surgery for orthopedic fractures. We enrolled patients who presented to our emergency department due to traumatic fractures between 2016 and 2017. We collected urine samples within 24 hours after the patients had undergone surgery to determine the presence of lipiduria. Hypoxemia was defined as an SpO2 <95% determined with a pulse oximeter during the hospitalization. Patients’ anthropometric data, medical history, and laboratory test results were collected from the electronic medical record. Logistic regression analyses were used to determine the associations of clinical factors with postoperative lipiduria and hypoxemia with multivariate adjustment. A total of 144 patients were analyzed (mean age 51.3 ± 22.9 years, male 50.7%). Diabetes (odd ratio 3.684, 95% CI 1.256-10.810, p=0.018) and operation time (odd ratio 1.005, 95% CI 1.000-1.009, p=0.029) were independently associated with postoperative lipiduria, while age (odd ratio 1.034, 95% CI 1.003-1.066, p=0.029), body mass index (odd ratio 1.100, 95% CI 1.007-1.203, p=0.035), and operation time (odd ratio 1.005, 95% CI 1.000-1.010, p=0.033) were independently associated with postoperative hypoxemia. We identified several factors independently associated with postoperative lipiduria and hypoxemia in patients with fracture undergoing surgical intervention. Operation time was associated with both postoperative lipiduria and hypoxemia, and we recommend that patients with prolonged operation for fractures should be carefully monitored for clinical signs related to fat embolism syndrome

Aim. This study aims to define the normal postoperative presepsin kinetics in patients undergoing primary cementless total hip replacement (THR). Methods. Patients undergoing primary cementless THR at our Institute were recruited. At enrollment anthropometric data, smocking status, osteoarthritis stage according to Kellgren and. Lawrence, Harris Hip Score (HHS), drugs assumption and comorbidities were recorded. All the patients underwent serial blood tests, including complete blood count, presepsin (PS) and C-Reactive Protein (CRP) 24 hours before arthroplasty and at 24-, 48-, 72- and 96-hours postoperatively and at 3-, 6- and 12-months follow-up. Statistical analysis was performed with SPSS v25.0 (SPSS Inc, Chicago, IL, USA). The Wilcoxon and Kruskal-Wallis tests followed by the Dunn multiple comparison post hoc tests were carried out. Correlations between PS, CRP and TOT were assessed using the Spearman rank correlation coefficient. P values below 0.05 were considered significant. Results and conclusion. A total of 96 patients were recruited (51 female; 45 male; mean age= 65.74±5.58) were recruited. The mean PS values were: 137.54 pg/ml at baseline, 192.08 pg/ml at 24-hours post-op; 254.85 pg/ml at 48-hours post-op; 259 pg/ml at 72-hours post-op; 248.6 pg/ml at 96-hour post-op; 140.52 pg/ml at 3-months follow-up; 135.55 pg/ml at 6-months follow-up and 130.11 pg/ml at 12-months follow-up. In two patients (2.08%) a soft-tissue infection was observed; in these patients higher levels (>350pg/mL) were recorded at 3-months follow-up. The lack of a presepsin decrease at 96 hours post-operatively should be a predictive factor of infection

Introduction. Hip arthroplasty is considered common to patients aged 65 and over however, both Jennings, et al., (2012) and Bergmann (2016) found THA patients are substantially younger with more patients expecting to return to preoperative activity levels. With heavier, younger, and often more active patients, devices must be able to support a more demanding loading-regime to meet patient expectations. McClung (2000) demonstrated that obese patients can display lower wear-rates with UHMWPE bearing resulting from post-operative, self-induced reduced ambulatory movement, thus questioning if obese kinematics and loading are indeed the worst-case. Current loading patterns used to test hip implants are governed by ISO 14242-1 (2014). This study aimed to characterize a heavy and active population (referred to as HA) and investigate how the gait profile may differ to the current ISO profile. Method. A comprehensive anthropometric data set of 4082 men (Gordon, CC., et.al., 2014) was used to characterize a HA population. Obese and HA participants were classed as BMI ≥30 however HA participants were identified by applying anthropometric ratios indicative of lower body fat, namely “waist to height” (i.e. WHtR <0.6) and “waist to hip” (i.e. WHpR <0.9). Findings. Of 491 obese participants 61 were identified as HA (i.e. BMI> 30, WHpR<0.9; WHtR<0.6) (Figure 1). These characteristics were validated against a population of elite rugby players that were found to be a true reflection of HA patients (Figure 2). Combining the Army and Rugby populations resulted in a weight of 123kg for the 95. th. percentile, which based on 3× body weight (as referenced in ISO14242-1) would equate to a peak simulator load of 3620N. Conclusion. Characterization of a HA population was successfully defined as clinically obese by BMI, but with WHtR and WHpR associated with lower body fat. The author was unable to identify gait characteristics of a HA population through existing literature. Future Work. A gait-lab based study will be used to compare literature-based kinematics of obese subjects to those of HA subjects. A worst-case gait cycle can then be established for standard walking and other activities and translated into hip simulator parameters for HA patients

Introduction. Distraction histogenesis is utilised for cosmetic reasons in patients with constitutional short stature, achondroplasias, or height dysphoria. One of the considerations of patients and surgeons alike, is the preservation of aesthetically acceptable body proportions after the lengthening i.e which segment of the lower limb to lengthen and by how much, in order to preserve the patient's proportions within -or as close as possible to- the normal range of human body proportions. Sound anthropometric data on the normal range of the human body proportions is currently lacking. The aim of this study is to calculate the normal range of the ratio between the lengths of the lower limb, upper limb, femur, tibia, stature and trunk. Methods. Data form standardized measurements of the lengths of the tibia, femur, arm, stature, lower limb, upper limb was obtained from a sample population of 6068 healthy men and women servicing in the US Army. The mean, median, range and standard deviation were calculated for the following ratios of lengths: whole lower limb/leg, Stature/leg, Whole lower limb/thigh, Stature/thigh, Siting height/whole lower limb, Stature/Whole lower limb, Arm Span/Stature, Whole upper limb/Whole lower limb. Results. The ratios show normal distribution. Results are presented separately for men and women for the total sample population and for subgroups based on ethnic origin (White, Black, Hispanic and Asian). Discussion. This study is one of the first to provide specific anthropometric data from a large sample population relevant to the evidence-based preoperative planning and patient counselling before cosmetic limb lengthening procedures

Designs of medical devices are tested for their mechanical behaviour, ability to transfer the load that is normally bore by the healthy tissue, and prove of the resistance to fatigue. The virtual testing in silico is widely accepted technique based on three sets of input data – geometry is normally obtained from CT or MRI scan as well as the tissue density that is translated into mechanical properties of the tissue. The virtual behaviour of the system is controlled by set of constrains accordingly while the third set of data consist of the load that system normally transfers through the load-bearing tissue. The magnitude and character of the load is highly dependent on the physical activity, external loads, physical condition of the subject and its specific factors such as gender, health condition, etc. Most of the published simulations use estimated simplified loads, which barely simulate the real behaviour of the system. The evaluation of the spinal load published some years back estimated a normal (N) and shear force (S) accompanied by the flexing moment (M). Due to lack of experimental possibility we used these data to test the biomechanical response of the lumbar segment with isotropic material models of all tissues. Then we investigated the possibility to evaluate muscular forces and their recruitment. It is a complex task and even today it is not possible to measure directly in vivo all muscular forces contributing to the movement. The musculo-skeletal system is a statically indeterminate system. The forces can be solved by means of computational modelling based on the measured trajectories of the body motion and additional optimization functions combined with static equations. The trajectories were recorded by the fast camera system in our motion laboratory and consequently exported into an open simulation software that uses a generic skeleton with around two hundreds muscle fascicles. The skeleton was scaled to correspond to our subject's anthropometric data and further scaling to mock-up the generic vertebrae was performed to eliminate discrepancies between the generic and subject's bones. Once these adjustments were done a kinematics and inverse dynamics modules were engage with selected objective function controlling the muscular recruitment that the max. relative muscular force is as small as possible. The 84 muscular forces acting on the segment were exported to a text file in APDL language and uploaded in the Finite Element (FE) database. The results of FE analysis were compared to the results obtained earlier using N,S,M load [1]. The comparison between the two models shows that the results of segment's total displacement was reduced by 36 percent compared to initial results. The stress and stress intensity increased six times. The identical model with orthotropic material showed reduced displacement by 80 percent and the stress and stress intensity was reduced by 60 percent compared to initial results

Introduction. The purpose of this study was to experimentally evaluate impingement and dislocation of total hip replacements while performing dynamic movements under physiological-like conditions. Therefore, a hardware-in-the-loop setup has been developed, in which a physical hip prosthesis actuated by an industrial robot interacts with an in situ-like environment mimicked by a musculoskeletal multibody simulation-model of the lower extremity. Methods. The multibody model of the musculoskeletal system comprised rigid bone segments of the lower right extremity, which were mutually linked by ideal joints, and a trunk. All bone geometries were reconstructed from a computed tomography set preserving anatomical landmarks. Inertia properties were identified based on anthropometric data and by correlating bone density to Hounsfield units. Relevant muscles were modeled as Hill-type elements, passive forces due to capsular tissue have been neglected. Motion data were captured from a healthy subject performing dislocation-associated movements and were fed to the musculoskeletal multibody model. Subsequently, the robot moved and loaded a commercially available total hip prosthesis and closed the loop by feeding the physical contact information back to the simulation model. In this manner, a comprehensive parameter study analyzing the impact of implant position and design, joint loading, soft tissue damage and bone resection was implemented. Results. The parameter study revealed a generally high dislocation risk for the seating-to-rising with adduction scenarios. Improper implant positioning or design could be compensated by adjusting prosthesis components correspondingly. Gluteal insufficiency or lower joint loading did not result in higher impingement or dislocation risk. However, severe malfunction of the artificial joint was found for proximal bone resection. Discussion. Previous testing setups ignored the impact of active muscles or relied on simplified contact mechanics. Herein, total hip replacement stability has been investigated experimentally by using a hardware-in-the-loop simulation. Thereby, several influencing factors such as implant position and design as well as soft tissue insufficiency and imbalance could be systematically evaluated with the goal to enhance joint stability

Introduction. Precise implant matching with a resected bony surface is a crucial issue to ensure a successful total knee arthroplasty (TKA). Extremely undersized or oversized components should be avoided. Therefore, we should measure the exact anthropometric data of the resected bony surface preoperatively or intraoperatively. The purpose of this study was to intraoperatively analyze the exact anthropometric proximal tibial data of Japanese patients undergoing TKA and correlate these measurements to the dimensions of current prosthetic systems. Patients and Methods. Three hundred and seventy-three knees in 299 Japanese patients were included in this study. There were 246 women and 53 men with a mean age of 74 (range: 63–85) years. All TKAs were performed by 3 senior surgeons (TS, AK, and NM). The bone cut in the proximal tibia was made perpendicular to the longitudinal axis of the tibia in the frontal plane. Intraoperative measurements of the proximal tibial cut surface were taken after proximal tibial preparation. Akagi's line (center of the posterior cruciate ligament tibial insertion to the medial border of the patellar tendon attachment) was adopted as the anteroposterior axis line of the proximal tibia. A mediolateral (ML) line was drawn perpendicular to Akagi's line. Then, anteroposterior (AP), lateral anteroposterior (lAP), and medial anteroposterior (mAP) lines were drawn as shown in Figure 1. Results. There was a significant positive correlation between lAP and ML dimensions. Although there also was a significant positive correlation between lAP and mAP dimensions, individual knees presented much scatter (Figure 2). The lAP dimension was smaller than the mAP dimension in all knees by a mean of 4.5 ± 1.9 mm. The proximal tibia exhibited asymmetry between the lateral and medial plateaus. The recent data of 177 knees indicated that Akagi's line was located 1.0 ± 1.2 mm medial to the AP line. A comparison of the morphologic data and the dimensions of the implants, one of which was a symmetric tibial component (NexGen: Zimmer, Warsaw, Indiana), and the other asymmetric (Genesis II: Smith & Nephew, Memphis, Tennessee), indicated that an asymmetric tibial component could be beneficial in maximizing the coverage of the tibial plateau. However, the size variation of the asymmetric tibial component was poor and the lAP and mAP dimensions showed much scatter; thus, we should measure the proximal tibia and choose the proper tibial component during surgery. Conclusions. This study provides important reference data that may be useful for designing proper tibial components for Japanese patients

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

The accurate assessment of skeletal maturity is essential in the management of orthopaedic conditions in the growing child. In order to identify the time of peak height velocity (PHV) in adolescents, two systems for assessing skeletal maturity have been described recently; the calcaneal apophyseal ossification method and the Sanders hand scores.

The purpose of this study was to compare these methods in assessing skeletal maturity relative to PHV. We studied the radiographs of a historical group of 94 healthy children (49 females and 45 males), who had been followed longitudinally between the ages of three and 18 years with serial radiographs and physical examination. Radiographs of the foot and hand were undertaken in these children at least annually between the ages of ten and 15 years. We reviewed 738 radiographs of the foot and 694 radiographs of the hand. PHV was calculated from measurements of height taken at the time of the radiographs.

Prior to PHV we observed four of six stages of calcaneal apophyseal ossification and two of eight Sanders stages. Calcaneal stage 3 and Sanders stage 2 was seen to occur about 0.9 years before PHV, while calcaneal stage 4 and Sanders stage 3 occurred approximately 0.5 years after PHV.

The stages of the calcaneal and Sanders systems can be used in combination, offering better assessment of skeletal maturity with respect to PHV than either system alone.

Cite this article: Bone Joint J 2015;97-B:1710–17.

Introduction. Dislocation of total hip replacements (THRs) remains a severe complication after total hip arthroplasty. However, the contribution of influencing factors, such as implant positioning and soft tissue tension, is still not well understood due to the multi-factorial nature of the dislocation process. In order to systematically evaluate influencing factors on THR stability, our novel approach is to extract the anatomical environment of the implant into a musculoskeletal model. Within a hardware-in-the-loop (HiL) simulation the model provides hip joint angles and forces for a physical setup consisting of a compliant support and a robot which accordingly moves and loads the real implant components [2]. The purpose of this work was to validate the HiL test system against experimental data derived from one patient. Methods. The musculoskeletal model includes all segments of the right leg with a simplified trunk. Bone segments were reconstructed from a human computed tomography dataset. The segments were mutually linked in the multibody software SIMPACK (v8.9, Simpack AG, Gilching, Germany) by ideal joints starting from the ground-fixed foot. Furthermore, inertia properties were incorporated based on anthropometric data. Inverse dynamics was used to obtain muscle forces. Thus, optimization techniques were implemented to resolve the distribution problem of muscle forces whereas muscles were assumed to act along straight lines. For validation purposes the model was scaled to one patient with an instrumented THR [1]. Averaged kinematic measurements were used to obtain joint angles for a knee-bending motion. Then, the model was exported into real-time capable machine code and embedded into the HiL environment. Real implant components of a standard THR were attached to the endeffector of the robot and the compliant support. Finally, the HiL simulation was carried out simulating knee-bending. Experimentally measured hip joint forces from the patient [1] were used to validate the HiL simulation. Results. According to the joint angles obtained a knee-bending motion was carried out during the HiL simulation (Fig. 1). Predicted components of the hip joint force were in-between the envelopes of measured in-vivo data with partial deviation of the y-component (Fig. 2). The force application by the robot agreed well with the force values provided by the model. Discussion. Previous quasi-static mechanical setups for testing subluxation and dislocation of THRs neglected the impact of soft tissue structures on actual joint loading. Therefore, we combine the advantages of robot-based testing and numerical simulations within a HiL approach for dynamic analyses of THRs [2]. Thereby, validation is required to enhance the credibility of test results. The data presented demonstrate that the HiL test system with the embedded musculoskeletal model is capable of providing comparable THR loading as derived from in-vivo data. Certain deviations of the joint force's y-component will be the focus of up-coming model improvements. By considering dislocation-associated movements such as deep knee-bending, the influence of implant design and positioning on THR stability can be evaluated under reproducible, physiological-like conditions in subsequent studies

Purpose. The majority (73%) of orthopaedic surgeons in Canada prefer using semitendinosus-gracilis (STG) autograft for ACL reconstruction. However, there is large variation in tendon size between individuals which makes pre-operative estimation of graft size unpredictable. Inadequate graft size may require an alternative source of graft tissue that should be planned prior to surgery. The purpose of this study is to determine if clinical anthropometric data and MRI measurements of STG tendons can be used to predict hamstring graft size. Method. One-hundred and fourteen patients with ACL deficiency awaiting reconstruction using hamstring autograft were retrospectively evaluated. The following information was obtained from patient charts: height, weight, body mass index (BMI), age, and gender. Cross-sectional area (CSA) of gracilis (G) and semitendinosus (ST) tendons were determined from pre-operative MRI scans using NIH ImageJ analysis software. Actual STG graft diameters were obtained from operative reports. Correlations between patient height, weight, BMI, age, gender, ST-CSA, G-CSA, STG-CSA and intraoperative graft size were calculated to determine the association between these variables. Multiple stepwise regression was performed to assess the predictive value of these variables to intraoperative graft diameter. In addition, three investigators with no radiological experience made independent measurements of the ST and G tendons to determine the inter-rater reliability (ICC) of MRI measurements. Results. All variables were independently correlated with intraoperative graft size (p<0.001). However, based on multiple stepwise regression analysis, only models including STG-CSA (r2=.212; p<.001); STG-CSA and sex (r2=.285; p<.001); and STG-CSA, sex and weight (r2=.294; p<.001) were found to be significant predictors of graft size (when co-variation in other factors was controlled). Inter-class correlation coefficients demonstrated very high agreement between raters for measurements of the ST, G and STG (.816, .827, .863, respectively). Conclusion. Measurement of tendon CSA from MRI images is very reliable. A model including STG-CSA, sex and weight was found to be strongly predictive of hamstring graft diameter for ACL reconstruction. This model may enhance our ability to predict adequate graft size and identify instances that other graft tissues may be a better option. The results of this study may improve pre-operative planning for ACL reconstruction

The purpose was to investigate back pain and disability and their relationship to vertebral changes in patients with untreated Scheuermann's. Overall, 136 patients who had attended the outpatient clinics between 1950 and 1990 for Scheuermann's were contacted, 49 of them (12 females, 37 males) responded. There was no difference in the baseline data between responders and non-responders. From radiographs, th-kyphosis, l-lordosis, and scoliosis were measured. The number of affected vertebrae and the degree of wedging were registered. Anthropometric data, occurrence of back pain, disability scores, and employment status were compared to a representative sample (n=3835) of the normal population. After mean follow-up of 37 (6.5;25.9-53.7) y, their average age was 58.8 (8.2;44.4.-79.3) y. Male patients were significantly taller than the control subjects. Female patients were on average 6 kg heavier (P=0.016) and their mean BMI was higher (23.9 kg/m. 2. vs 20.8 kg/m. 2. ,P=0.001) at age 20 than in the controls. Females had a greater mean kyphosis than males (51.7 vs. 43.2°, p=0.11). There was no correlation between the degree of thoracic kyphosis and disability. Scheuermann's patients had an increased risk for constant back pain (P=0.003), a 2.6-fold risk for disability because of back pain during the past 5 years (P=0.002), a 3.7-fold risk for back pain during the past 30 days (P<0.001), and a 2.3-fold risk for sciatic pain (P=0.005). They reported a poorer quality of life (p<0.001) and general health (p<0.001). There was no difference in working ability and employment status between patients and controls

Introduction. Despite extensive research, the cause of adolescent idiopathic scoliosis (AIS) is still largely unclear. Girls with AIS tend to be taller and leaner, and have a lower body-mass index (BMI) and lower bone mass, than do healthy girls. Recent MRI studies have shown the presence of relative anterior spinal overgrowth in girls with AIS. The lower bone mineral status and BMI could be related to dysfunctional central regulation pathway of growth, bodyweight, and bone metabolism. Following several interesting reports on the role of leptin in regulation of the above pathway in animals and human beings, our recent study has shown a low leptin concentration in girls with AIS girls compared with healthy adolescents. This finding leads to our new hypothesis that abnormal leptin bioavailability could be associated with the lower bodyweight, lower bone mineral density, and relatively disproportional endochondral skeletal growth in AIS. This study aimed to investigate the leptin bioavailability in girls with AIS. Methods. 53 girls with AIS and 27 healthy girls (aged 11–16 years) were recruited in this preliminary study. Clinical and anthropometric data were obtained. Blood samples were obtained for ELISA of leptin and soluble leptin receptor (sOB-R). Independent Student's t test and multivariate regression were used in group comparison. Results. The AIS group had significantly lower BMI and longer arm span than did controls. Additionally, girls with AIS had significantly higher soluble leptin receptor concentrations (22·1 ng/mL [□}6·9] vs 17·8 ng/mL [4·4]; p<0·01). However, the leptin concentration (7·6 ng/mL [□}5·3] vs 8·7 ng/mL [□}6·0]) and the leptin/sOB-R ratio (0·38 [□}0·28] vs 0·56 [□}0·47]) were similar to that of the controls. In girls with AIS, the leptin, sOB-R, and the leptin/sOB-R ratio correlated well with bodyweight and BMI. After adjustment for BMI, sOB-R in girls with AIS was significantly higher than in controls (r=0·37, p=0·042). Conclusions. This preliminary report showed that the soluble leptin receptor could be abnormal in girls with AIS. Leptin and sOB-R are related to bodyweight. sOB-R is a major modulator of leptin concentration in circulation, the abnormality of which may lead to the retention of leptin in the circulation and thus abnormal regulatory effect. In this study, girls with AIS had lower BMI and longer arm span, which may reflect the possible change resulting from abnormal leptin bioavailability. Further longitudinal study with larger sample size would be useful to help to understand the long-term effect of the low leptin and high sOB-R in girls with AIS on their bodyweight and skeletal development. It is also noteworthy to study the mechanism of increased sOB-R in AIS

We aimed to obtain anthropometric data on Korean knees and to compare these with data on commonly available total knee arthroplasties (TKAs). The dimensions of the femora and tibiae of 1168 knees were measured intra-operatively. The femoral components were found to show a tendency toward mediolateral (ML) under-coverage in small femurs and ML overhang in the large femurs. The ML under-coverage was most prominent for the small prostheses. The ML/anteroposterior (ML/AP) ratio of Korean tibiae was greater than that of tibial components. This study shows that, for different reasons, current TKAs do not provide a reasonable fit for small or large Korean knees, and that the ‘gender-specific’ and ‘stature-specific’ components help for large Korean femurs but offer less satisfactory fits for small femurs. Specific modifications of prostheses are needed for Asian knees

Purpose: The purpose of the study is to measure the resected surface of femur of the Korean patients during total knee arthroplasty surgery and to compare these measurements with the dimensions of femoral implants in current use. Materials and Methods: Morphometric data (7 parameters) were obtained in 500 cases of resected femur of the Korean patients who underwent total knee arthroplasties, and these data were compared with four current implants designs. Results: The range of medial-lateral width at the given implant varies widely. The anterior width of the resected femur at the condyle is smaller than the widths of the most implants, creating an overhang. The medial-lateral width of the condyle at the level of transepicondylar line is wider than most of the present implants. However the widths of the resected posterior condyles were narrower at anterior-posterior alignment, causing overhang at the posterior condyles. We felt this will cause anterior tensioning at flexion and reduce the ability to flex further. Conclusion: The shape of the femur in Korean knee is different from that of current TKR implants in use, which are based on the anthropometric data of Caucasians. Therefore new design, better suited to the morphometric measurements of Korean knee, is necessary. Though historically this mismatch of the implant was well tolerated, new design to better fit the measurement of Korean knee should be considered for functional enhancement such as range of motion, durability and function

Most studies on LBP have focused on adults although many investigations have shown that the roots of LBP lie in adolescence. Several mechanical, physical and behavioral factors have associated with non-specific LBP in adolescents. To our knowledge no previous study has investigated using advanced statistics all previously reported parameters together with psychological and psychosocial factors on LBP in adolescents aged 15–19 years. 688 students aged 16± 1 years from 5 randomly selected high schools participated in this multifactorial study and completed a questionnaire containing questions on daily activity, backpacks carrying, psychological and psychosocial behavior. Anthropometric data as well biplane spinal curvatures together with questionnaire results were included in the analysis using advanced statistics. LBP reported 41% of the participants. Generally, statistically significant correlations were found between LBP(0.002), physical activity(P< 0.001), physician consultation(P=0.024) and depression (P< 0.001) Gender-related differences were shown regarding LBP intensity(P=0.005) and frequency(P=0.013), stress(P< 0.03), depression (P=0.005) and nervous mood(P=0.036) in favor of male students. Male adolescents had continuously energy (P=0.0258) and were calm (P=0.029) in contrast to female counterparts. LBP was gender-related and was less common in adolescents with frequent activity. Adolescent girls with stress, depressive mood and low energy have more LBP than boys that makes physician consultation for LBP more common in female adolescents. Systematic physical activity and control of psychological profile should decrease LBP frequency and intensity

Study design: Prospective multifactorial study on low back pain (LBP) in adolescents. Background data: Most studies on LBP have focused on adults although may investigations have shown that the roots of LBP lie in adolescence. Several mechanical, physical and behavioral factors have associated with non-specific LBP in adolescents. To our knowledge no previous study has investigated using advanced statistics all previously reported parameters together with psychological and psychosocial factors on LBP in adolescents aged 15–19 years. Material and Methods: 688 students aged 16± 1 years from 5 randomly selected high schools participated in this study and completed a questionnaire containing questions on daily activity, backpacks carrying, psychological and psychosocial behavior. Anthropometric data as well biplane spinal curvatures together with questionnaire results were included in the analysis using advanced statistics. Results: LBP reported 41% of the participants. Generally, statistically significant correlations were found between LBP(0.002), physical activity(P< 0.001), physician consultation(P=0.024) and depression (P< 0.001) Gender-related differences were shown regarding LBP intensity(P=0.005) and frequency(P=0.013), stress(P< 0.03), depression (P=0.005) and nervous mood(P=0.036) in favor of male students. Male adolescents had continuously energy (P=0.0258) and were calm (P=0.029) in contrast to female counterparts. Discussion: LBP was gender-related and was less common in adolescents with frequent activity. Adolescent girls with stress, depressive mood and low energy have more LBP than boys that makes physician consultation for LBP more common in female adolescents. Conclusion: Systematic physical activity and control of psychological profile should decrease LBP frequency and intensity