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Vehicle positioning generally uses the global navigation satellite system (GNSS), but systems of different levels significantly affect positioning accuracy. Moreover, it is greatly affected by weather that may cause inaccurate positioning due to excessive cloud cover. In the technology of self-driving cars, how to achieve stable and accurate positioning is a critical topic. This research first uses RTK-GPS, LiDAR, and cameras to build high-precision map information and realize vehicle positioning functions. By using the normal distribution transform (NDT), ORB-SLAM, and iterative closest point (ICP) were matched to the feature points of the current map with the pre-built map to complete the vehicle positioning system. If the change of static objects in the map was detected during the positioning process, the map was updated. Finally, the performance of the proposed system was verified on the road on the campus.

In total hip arthroplasty (THA), the accurate positioning of implants is the key to achieve a good clinical outcome. Computer-assisted orthopaedic surgery (CAOS) has been developed for more accurate positioning of implants during the THA. There are passive, semi-active, and active systems in CAOS for THA. Navigation is a passive system that only provides information and guidance to the surgeon. There are 3 types of navigation: imageless navigation, computed tomography (CT)-based navigation, and fluoroscopy-based navigation. In imageless navigation system, a new method of registration without the need to register the anterior pelvic plane was introduced. CT-based navigation can be efficiently used for pelvic plane reference, the functional pelvic plane in supine which adjusts anterior pelvic plane sagittal tilt for targeting the cup orientation. Robot-assisted system can be either active or semi-active. The active robotic system performs the preparation for implant positioning as programmed preoperatively. It has been used for only femoral implant cavity preparation. Recently, program for cup positioning was additionally developed. Alternatively, for ease of surgeon acceptance, semi-active robot systems are developed. It was initially applied only for cup positioning. However, with the development of enhanced femoral workflows, this system can now be used to position both cup and stem. Though there have been substantial advancements in computer-assisted THA, its use can still be controversial at present due to the steep learning curve, intraoperative technical issues, high cost and etc. However, in the future, CAOS will certainly enable the surgeon to operate more accurately and lead to improved outcomes in THA as the technology continues to evolve rapidly.

Displaced femoral neck fracture in elderly patients has been treated with hemiarthroplasty as the treatment of choice. Fever following HA is common in these elderly patients. The aim of this study was to determine which post-HA fever workup could be beneficial in this group of patients.A total of 272 consecutive patients aged ≥70 years undergoing HA for displaced femoral neck fracture were retrospectively investigated. Postoperative fever (POF) was defined as any recorded body temperature ≥38°C in the early postoperative period. POF in each patient was characterized by the maximum temperature, the day of the first fever, and frequency of fever, stratified as either single or multiple fever spikes. Medical records were reviewed to identify positive fever workups and febrile complications.Of 272 patients, 135 (49.6%) developed POF. A total of 428 routine diagnostic tests were performed in all patients with POF, of which only 57 tests (13.3%) were positive. Urinalysis showed the highest positive rate (21.9%), followed by urine culture (14.3%), chest x-ray (12.6%), and blood culture (1.1%). The most common febrile complication was pneumonia (12.6%), followed by urinary tract infection (8.1%). On multivariate logistic regression for positive workups, only fever after postoperative day (POD) 2 was a risk factor for positive chest x-ray (OR 3.86, p=0.016) and urine culture (OR 5.04, p=0.019). Moreover, fever after POD 2 (OR 6.93, p0.0001) and multiple fever spikes (OR 2.92, p=0.026) were independent predictors of infectious febrile complications.Routine workup for POF following hemiarthroplasty in elderly patients with displaced femoral neck fracture is not warranted. However, for fever after POD 2 and multiple fever spikes, chest x-ray and urinalysis would be necessary to rule out the two most common febrile complications such as pneumonia and urinary tract infection.

Background While hemiarthroplasty (HA) is considered the treatment of choice for displaced femoral neck (FN) fractures in elderly patients, HA has been partly performed as an alternative treatment option for unstable intertrochanteric (IT) fractures. However, there is a paucity of data regarding the risk and availability of HA for unstable IT fractures compared to HA for displaced FN fractures in elderly patients. Therefore, we performed this case-control study to determine whether HA for unstable IT fractures provides clinical results and survival comparable to HA for displaced FN fractures in elderly patients. Hypothesis HA for unstable IT fractures in elderly patients provides clinical results and 1-year survival comparable to HA for displaced FN fractures in the same aging group. Materials and methods We identified 80 patients aged 75 years or older, who underwent cementless bipolar HA for unstable IT fracture (AO/OTA type 31-A2.2/3 and A3.3). Their clinical results and 1-year survival were compared to the matched control group of 80 patients with displaced FN fractures (Garden type 3 and 4) treated with the same procedure. Perioperative results, postoperative complications, and 1-year survival were investigated between the two groups. Functional outcome was assessed by walking status and Harris hip score (HHS) 6 months after surgery. Results Operating time was significantly longer in the IT group than the FN group (97.3 min [50 to 255] vs. 79.3 min [40 to 175], P = 0.016). However, the two groups did not significantly differ regarding perioperative results, such as total blood loss, transfusion, intraoperative fracture, length of hospital stay, and postoperative complication. No statistically significant differences in walking status and HHS were observed between the groups. No significant difference in cumulative survival was observed between the two groups (P = 0.836), with a 1-year survival rate of 80% (95% confidence interval [CI], 71.8 to 87.5) in the IT group and 82% (95% CI, 73.1 to 89.4) in the FN group. Conclusion HA for unstable IT fractures in elderly patients showed clinical results and 1-year survival comparable to HA as the treatment of choice for displaced FN fractures in the same aging group. Level of evidence Level III, case-control study.

Background Intramedullary (IM) nailing is widely performed in elderly patients with trochanteric fractures. Thus, it is important to identify causative factors associated with fixation failure. We investigated fixation failures after IM nailing in elderly patients with trochanteric fractures and compared the failure group with nonfailure group to identify risk factors of fixation failure. Methods A total of 396 patients aged 65 years or older underwent IM nailing for trochanteric fractures between January 2012 and August 2016 at our institution. Of those, 194 patients who were followed up for more than 12 months were enrolled in this study; 202 patients were excluded due to death during follow-up, bedridden status before injury, and loss to follow-up. All patients underwent plain radiography and preoperative computed tomography (CT). Results Fixation failure occurred in 11 patients (5.7%). Seven patients had stable fractures (AO/OTA); eight patients had basicervical fractures (confirmed by CT). Five patients had comminution in the greater trochanter (confirmed by CT). Regarding fracture reduction, eight patients showed discontinuity in the anterior cortex. The position of the lag screw on the lateral view was in the center in six patients and in a posterior area in the other five patients. On the basis of comparison with the 183 patients without fixation failure, risk factors of fixation failure were higher body mass index (BMI; p = 0.003), basicervical type of fracture (p = 0.037), posterior placement of the lag screw on the lateral view (p < 0.001), and inaccurate reduction of the anterior cortex (p = 0.011). Conclusions Among the risk factors of fixation failure after IM nailing in elderly patients with trochanteric fractures, discontinuity of the anterior cortex and posterior position of the lag screw are modifiable surgeon factors, whereas higher BMI and basicervical type of fracture are nonmodifiable patient factors. Therefore, care should be taken to avoid fixation failure in IM nailing for patients with a basicervical type of fracture or higher BMI or both.

Objectives The rotational alignment is definitely important in the long bones such as tibias and femurs. We also predict the importance of rotational alignment in the trochanteric fractures. So we measured torsional malalignment in trochanteric fracture and anlaysed their risk factors and their clinical significance. Methods A total of 109 inpatients who had undergone internal fixation following trochanteric fracture and a postoperative pelvic CT scan between 2008 and 2013, with at least one year follow-up, were selected. Factors that affect torsional malalignment, such as age, gender, fracture stability, injured area, operative time, time of surgery after admission, and ASA status, were investigated. Factors that affect the patients’ clinical results in malrotation, including ambulation time after surgery, postoperative complication rates, pain assessment of VAS one year postoperatively and Koval score, were also investigated. Results Of the 109 subjects, torsional malalignment was observed in 28 (25.7%) subjects with a mean torsional malalignment angle of 20.7° (range: −31.2° to 27.1°). Torsional malalignment risk factors were fracture stability (p = 0.021) and operative time (p = 0.043). In terms of the time to ambulation after surgery, the postoperative complication rates, and the VAS and Koval scores at one year postoperatively, no statistically significant difference was observed between the torsional malalignment patients and the non-deformity patients. Conclusions In this study, 25.7% of the patients who had undergone internal fixation following trochanteric fracture experienced torsional malalignment. Major factors of the torsional malalignment were an unstable fracture and the consequent delay in the operative time. But the torsional malalignment was deemed to have no effect on clinical results.

Posterior wall fractures, which are the most common type of acetabulum fracture, are frequently accompanied with an avulsion tear of the posterior labral root as well as hip dislocation due to the injury mechanism. In the treatment of these fractures with an avulsed posterior labral root attached to posterior wall fragment, the use of a suture anchor can induce indirect reduction of a posterior wall fragment as well as direct repair of a labral root tear simultaneously. We describe the simple and efficient technique using a suture anchor in posterior wall acetabular fractures and surgical outcomes of two cases treated with this technique.

A new method with a simple algorithm was developed to accurately measure Poisson’s ratio of soft materials such as polyvinyl alcohol hydrogel (PVA-H) with a custom experimental apparatus consisting of a tension device, a micro X-Y stage, an optical microscope, and a charge-coupled device camera. In the proposed method, the initial positions of the four vertices of an arbitrarily selected quadrilateral from the sample surface were first measured to generate a 2D 1st-order 4-node quadrilateral element for finite element numerical analysis. Next, minimum and maximum principal strains were calculated from differences between the initial and deformed shapes of the quadrilateral under tension. Finally, Poisson’s ratio of PVA-H was determined by the ratio of minimum principal strain to maximum principal strain. This novel method has an advantage in the accurate evaluation of Poisson’s ratio despite misalignment between specimens and experimental devices. In this study, Poisson’s ratio of PVA-H was 0.44 ± 0.025 (n=6) for 2.6–47.0% elongations with a tendency to decrease with increasing elongation. The current evaluation method of Poisson’s ratio with a simple measurement system can be employed to a real-time automated vision-tracking system which is used to accurately evaluate the material properties of various soft materials.

Purpose The treatment of infected revision total hip arthroplasty (THA) is very challenging due to retained revision prosthesis, poor bone stock and soft tissue condition derived from previous revision surgeries, and comorbidities. The purpose of this study was to investigate the effectiveness and short-term outcomes of aggressive debridement and use of antibiotic-loaded cement beads with retention of the prosthesis for acute delayed or late infection of revision THAs. Materials and methods Ten consecutive patients with symptoms or signs of less than one-week evolution and well-fixed prostheses, were treated with this procedure and a postoperative course of organism-specific antibiotics for a minimum of 6 weeks. All hips presented with acute delayed or late infection of revision THAs. Patients with a mean age of 68.1 years (range, 59-78 years) underwent an average of 1.9 previous revision THAs (1-4) before the index surgery. The minimal follow-up was 2 years with a mean of 46.2 months (range, 24-64 months). Results There were 8 cures (80.0%) and 2 failures with no mortality during the study period. The 2 failures involved the same and resistant bacteria implicated in the primary infection (methicillin-resistant Staphylococcus aureus and Prevotella oralis, respectively). The mean Harris hip score was 65.2 (range, 26-83) and the mean visual analogue scale was 2.6 (range, 1-4) at final follow-up. Conclusion With a favorable success rate and no mortality, our procedure may be considered a safe and effective alternative for the treatment of acute delayed or late infection of revision THAs with well-fixed prostheses.

Background The purpose of the study was to evaluate the implant positions and clinical results of revision total hip arthroplasty (THA) using an imageless navigation with the concept of combined anteversion. Methods A total of 40 cementless revision THAs (24 men and 16 women) using an imageless navigation with the concept of combined anteversion were retrospectively evaluated. The concept of combined anteversion was applied in cup positioning based on Widmer's equation (cup anteversion + 0.7 × stem anteversion). The mean follow-up period was 80.7 months. Postoperatively, the inclination of the cup was evaluated on standard anteroposterior view of the radiograph, and the anteversion of the cup and femoral stem was evaluated using computed tomography scan. A cup inclination of 40° ± 10° and combined anteversion of the cup and femoral stem of 37° ± 10° based on Widmer's equation were regarded as the “safe zone.” Results The average anteversion of the revised femoral stems was 15.3° ± 2.9° (range, 9.5°-21.5°), whereas that of the remained femoral stems was 17.4° ± 9.7° (range, 4.2°-29.8°). The inclination, anteversion of the cup, and combined anteversion after revision THA were 42.3° ± 3.1° (range, 32.1°-48.2°), 25.0° ± 2.9° (range, 16.9°-29.5°), and 36.1° ± 3.4° (range, 27.2°-42.9°), respectively. Therefore, the position of the implants, relative to the safe zone, showed no outliers after the revision surgery. Neither dislocation nor osteolysis was observed after the surgery. Conclusion Favorable results of this study indicate that imageless navigation helps the surgeon in placing the components of revision THA in the safe zone. This study also shows that when this safe zone is consistently obtained, then no postoperative dislocations were observed in these patients over the 6-year follow-up period.

Background The purpose of the study is to evaluate the radiologic and functional results of greater trochanteric reattachment using the third-generation cable plate system in revision total hip arthroplasty (THA). Methods A total of 47 trochanteric fixations (27 men and 18 women; mean age of 60.2 years) using the third-generation cable plate system in revision THA were retrospectively evaluated. The mean follow-up was 80.4 months (range 27-148 months). The osteotomized greater trochanter was reattached using the Cable-Ready system (Zimmer, Warsaw, IN) and the Dall-Miles cable system (Stryker, Mahwah, NJ). The clinical results with Harris hip score, visual analog scale, and radiologic outcomes were evaluated. Results The mean Harris hip score was improved from 55.7 (range 17-72) preoperatively to 90.8 (range 68-100; P = .001) postoperatively, and the mean pain score was improved from 6.6 (range 3-10) to 2.5 (range 0-6; P = .001), respectively. Nonunion was observed in 6 hips (12.7%). Migration of the osteotomized greater trochanteric fragment (>1 cm) was seen in 8 hips (17.0%). Cable breakage occurred in 13 cases (27.6%). Although 5 cable plate systems were removed, there was no need for reattachment of the greater trochanter in this study. Conclusion This study showed a relatively high incidence of radiologic failure after greater trochanteric reattachment using the cable plate system in revision THA, although reattachments were not required and clinical outcome was relatively satisfactory. Periodic and close observation for the early detection of failure is necessary.

Wear particles are the major cause of osteolysis associated with failure of implant following total joint replacement. During this pathologic process, activated macrophages mediate inflammatory responses to increase osteoclastogenesis, leading to enhanced bone resorption. In osteolysis caused by wear particles, osteoprogenitors present along with macrophages at the implant interface may play significant roles in bone regeneration and implant osteointegration. Although the direct effects of wear particles on osteoblasts have been addressed recently, the role of activated macrophages in regulation of osteogenic activity of osteoblasts has scarcely been studied. In the present study, we examined the molecular communication between macrophages and osteoprogenitor cells that may explain the effect of wear particles on impaired bone forming activity in inflammatory bone diseases. It has been demonstrated that conditioned medium of macrophages challenged with titanium particles (Ti CM) suppresses early and late differentiation markers of osteoprogenitors, including alkaline phosphatase (ALP) activity, collagen synthesis, matrix mineralization and expression of osteocalcin and Runx2. Moreover, bone forming signals such as WNT and BMP signaling pathways were inhibited by Ti CM. Interestingly, TNFα was identified as a predominant factor in Ti CM to suppress osteogenic activity as well as WNT and BMP signaling activity. Furthermore, Ti CM or TNFα induces the expression of sclerostin (SOST) which is able to inhibit WNT and BMP signaling pathways. It was determined that over-expression of SOST suppressed ALP activity, whereas the inhibition of SOST by siRNA partially restored the effect of Ti CM on ALP activity. This study highlights the role of activated macrophages in regulation of impaired osteogenic activity seen in inflammatory conditions and provides a potential mechanism for autocrine regulation of WNT and BMP signaling mediated by TNFα via induction of SOST in osteprogenitor cells.

In elderly patients, osteoporosis can complicate revision total hip arthroplasty (THA). The SLR-Plus (Smith & Nephew, Memphis, TN) revision stem has a tapered, press-fit design, which we hypothesized could enhance stability in this population. Accordingly, we retrospectively analyzed data for 48 elderly patients who underwent revision THA using the SLR-Plus stem. The patients had a mean age of 66.5 years (range, 60-81 years) at surgery. They were monitored for a mean of 5.6 years (range, 3.4-8.0 years) after surgery. The mean Harris Hip Score improved from 67.8 to 91.6. No infection, dislocation, osteolysis, or stress shielding around stem were observed after surgery. The survivorship at an average of 5.6-year follow-up was 98%. These favorable results indicate that the SLR-Plus stem is useful in revision THA in elderly patients.

Periarticular fractures that occur in a previously osteoarthritic knee, especially in an elderly patient, will be associated with other comorbidities and is a treatment challenge. Early mobilization is a key treatment principle in the geriatric population. We present a case report of an elderly diabetic patient with osteoarthritis of the knee joint who sustained a patellar fracture and was treated with single-stage primary total knee arthroplasty and fixation of the patellar fracture.

Synovial chondromatosis is an uncommon condition and involvement of the glenohumeral joint is rare comparing its involvement of knee and hip. We report a case of synovial chondromatosis with its radiography, MRI and microscopic findings and treatment by arthroscopic synovectomy & loose body removal which have been developed in right shoulder of a 46 year-old-female and presented as impingement syndrome.

Clinical and radiographic findings of metallosis in relation to the clinical outcome of revision total hip arthroplasty were analyzed for 31 hips. Causes of metallosis were dissociation of polyethylene liner in 24 hips, catastrophic wear in 6, and the screw used for stem fixation in 1. Metallosis was grade I in 12 hips, grade II in 7, and grade III in 12. Osteolysis around the acetabular cup was observed in 24 (77.4%) of 31 hips. At the time of final follow-up evaluation, none of the hips showed osteolysis, acetabular cup migration, or any change in inclination. Although metallosis could not be completely eradicated in severe cases, the clinical outcome for these hips was favorable. This study demonstrates that metallosis frequently causes osteolysis and that complete elimination of it is not a prerequisite for the success of revision total hip arthroplasty.

Titanium (Ti) particle is one of the prosthetic materials commonly used in implantation and has frequently been implicated in pathogenesis such as periprosthetic osteolysis. In the present study, we undertook to understand the intracellular signalling pathway stimulated by exogenous Ti at Rat-2 fibroblasts. By reporter gene analysis following transient transfections, exogenous Ti was shown to stimulate c-fos serum response element (SRE)-dependent luciferase activities in a dose-dependent manner. In addition, Ti-induced SRE activation was shown to be dramatically repressed by RacN17, a dominant negative mutant of Rac1, suggesting that Rac GTPase is essential for the signalling of Ti to c-fos SRE. Furthermore, pretreatment with MAFP, an inhibitor of cytosolic phospholipase A(2) (cPLA(2)), MK886, an inhibitor of 5-lipoxygenase (5-LO), or indomethacin, a general inhibitor of cyclooxygenase (COX), also significantly repressed Ti-induced SRE activation, suggesting mediatory roles of cPLA(2) and subsequent arachidonic acid (AA) metabolisms to leukotrienes (LTs) and prostaglandins (PGs) in the Ti signalling to c-fos SRE. Consistent with these results, intracellular levels of leukotriene B(4) (LTB(4)) and prostaglandin E(2) (PGE(2)) were Rac-dependently elevated in cells exposed to Ti particles.

Synovial fluid plays an important role in lubricating synovial joints. Its main constituents are hyaluronic acid (HA) and gamma-globulin, acting as boundary lubricants for articular cartilage. The aim of the study was to demonstrate the concentration-dependent effect of HA and gamma-globulin on the boundary-lubricating ability of human osteoarthritis (OA) cartilage. Normal, early and advance stage articular cartilage samples were obtained from human femoral heads and in presence of either HA or gamma-globulin, cartilage frictional coefficient (mu) was measured by atomic force microscopy (AFM). In advanced stage OA, the cartilage superficial layer was observed to be completely removed and the damaged cartilage surface showed a higher m value (similar to 0.409) than the normal cartilage surface (similar to 0.119) in PBS. Adsorbed HA and gamma-globulin molecules significantly improved the frictional behavior of advanced OA cartilage, while they were ineffective for normal and early OA cartilage. In advanced-stage OA, the concentration-dependent frictional response of articular cartilage was observed with gamma-globulin, but not with HA. Our result suggested that HA and gamma-globulin may play a significant role in improving frictional behavior of advanced OA cartilage. During early-stage OA, though HA and gamma-globulin had no effect on improving frictional behavior of cartilage, however, they might contribute to disease modifying effects of synovial fluid as observed in clinical settings.

We investigated the extent to which phosphatidylinositol 3-kinase (PI 3-kinase) and Rac, a member of the Rho family of small GTPases, are involved in the signaling cascade triggered by tumor necrosis factor (TNF)-alpha leading to activation of c-fos serum response element (SRE) and c-Jun amino-terminal kinase (JNK) in Rat-2 fibroblasts. Inhibition of PI 3-kinase by LY294002 or wortmannin, two specific PI 3-kinase antagonists, or co-transfection with a dominant negative mutant of PI 3-kinase dose-dependently blocked stimulation of c-fos SRE by TNF-alpha. Similarly, LY294002 significantly diminished TNF-alpha-induced activation of JNK, suggesting that nuclear signaling triggered by TNF-alpha is dependent on PI 3-kinase-mediated activation of both c-fos SRE and JNK. We also found nuclear signaling by TNF-alpha to be Rac-dependent, as demonstrated by the inhibitory effect of transient co-transfection with a dominant negative Rac mutant, RacN17. Our findings suggest that Rac is situated downstream of PI 3-kinase in the TNF-alpha signaling pathway to the nucleus, and we conclude that PI 3-kinase and Rac each plays a pivotal role in the nuclear signaling cascade triggered by TNF-alpha.

Purpose The initial mechanism causing segmental instability is unclear: It is not known whether disc degeneration is a primary cause or a secondary result of instability. This study analyzed the relationship between the disc degeneration on MRI and positive spinal instability on dynamic flexion-extension radiographs obtained from low back pain patients. Methods MRI and flexion-extension dynamic roentgenography was obtained in 83 patients with low back pain and were studied to determine the relationship between the instability and disc degeneration. Results Of the 15 cases of young low back pain patients in the 3rd decade were positive instability on dynamic flexion-extension roentgenography; disc degeneration shown on MRI in 7 patients (44%); and normal disc in 8 (56%). Of the 61 cases of young low back pain patients over 4th decade were positive instability on dynamic flexion-extension roentgenography; disc degeneration shown on MRI in 58 patients (95%); and normal disc in 3 (5%). The relation between disc degeneration and instability was statistically inconsistent in the 3rd decade (p > 0.05), but consistent over 4th decade (p < 0.05). Conclusion These results indicate that, at a young age, lumbar instability showing disc degeneration on MRI is inconsistent and no relation between the disc degeneration on MRI and spinal instability on dynamic flexion-extension roentgenography is present. This shows that in disc degeneration, if the disc degeneration does not show on the MRI of a young low back pain patient with poitive instability with dynamic flexion-extension radiography, allowance must made for the fact that this will take some time.

The purpose of this study was to investigate the factors influencing functional outcomes in elderly patients with united intertrochanteric fractures treated with hip nails and to ascertain whether decreased femoral offset due to lag screw sliding has a negative effect on functional outcomes in these patients. This retrospective study included 65 patients older than 65 years with united intertrochanteric fractures treated with hip nails. Functional outcomes were assessed using the Short Form-36 (SF-36) and a visual analog scale (VAS) 6 months postoperatively. Mean patient age was 77.8 years (range, 65–90 years); mean follow-up was 20.7 months (range, 12–38 months). More lag screw sliding occurred as bone mineral density (BMD) decreased. It was also greater in unstable fractures and acceptable reduction status. Less accurate reduction and greater lag screw sliding showed significant negative effects on most subscales of the SF-36, especially Physical Functioning and Role Physical. A significant positive correlation was observed between the extent of lag screw sliding and VAS. Lag screw sliding affected by fracture type, reduction quality, and BMD has a negative effect on functional outcomes in elderly patients with united intertrochanteric fractures. Therefore, the preservation of anatomical femoral offset as much as possible is needed to obtain better functional outcome through the minimization of lag screw sliding by more accurate reduction, which is a controllable factor, especially in osteoporotic unstable intertrochanteric fractures. [ Orthopedics. 2014; 37(12):e1101–e1107.]

In recent years, advanced driver assistance system (ADAS) and intelligent traffic system (ITS) both are popular issues. This paper presents an efficient and accurate roadside sign recognition which can be used to collect traffic sign and point of interest (POI) information by any end-users with smart phones or driving video recorders. In order to achieve high recognition performance for the proposed scheme, the local binary pattern (LBP) operator is used for feature extraction with low computing complexity scheme, and the support vector machine (SVM) is also used to learn and classify roadside signs. Besides, this paper also utilizes an image based distance measurement method to obtain the distance between roadside signs and cameras by single camera view, thus the proposed scheme can be applied to general electronic devices with single camera such as smart phones, tablets, driving video recorders. The POI and distance information can be applied in ADAS, intelligent traffic system, navigation system, and GPS correction. Experimental results show the average accuracy of recognition for each roadside sign is 98.1873%, and the average recognition speed is less than 20 milliseconds per each sign. Also, the distance measurement method is workable to correct the GPS positions of POIs or users.

This paper proposes a fragile image watermarking scheme with recover ability based on local binary pattern (LBP). The local binary pattern operator is mostly used to extract localized spatial features for texture analysis, image classification, and pattern recognition. According to spatial relations of a natural image, a local binary pattern can be utilized to represent the localized relations of a pixel with its neighborhood. Each pixel measured by the LBP operator can be obtained its own local binary pattern as representation of local spatial relations. The proposed scheme utilizes the LBP operator to generate authentication data which are embedded into each image block with 3 × 3 pixels size for tamper detection and recovery. The recovery information is obtained by calculating the mean value of each image block, and then the mean value is converted into a binary string which is embedded into eight neighboring pixels' LSBs of each image block for image recovering. From the experimental results, the proposed scheme has efficient tamper detection, better image quality and recovering ability than Zhang and Shih's LBP based watermarking scheme.

In recent years, a crucial issue is the manner in which to safely transmit the secret information and prevent the detection of information. An extended visual cryptography with authentication technology for the original image was proposed in previous studies. Fang and Lin's scheme [3] combine the principle of traditional visual cryptography with authentication characteristic, when we fix the first share image and shift the other share image for certain unit, we can obtain the extra confidential data. But in traditional visual cryptography, secret pixels are expanded to cause the size of the recovered image is larger than the original one. So this study combined the non-expanded scheme with the extra ability of hiding confidential data to prevent the detection of information.

Background While hemiarthroplasty (HA) is considered the treatment of choice for displaced femoral neck (FN) fractures in elderly patients, HA has been partly performed as an alternative treatment option for unstable intertrochanteric (IT) fractures. However, there is a paucity of data regarding the risk and availability of HA for unstable IT fractures compared to HA for displaced FN fractures in elderly patients. Therefore, we performed a case control study to determine: 1) whether HA for unstable IT fractures provides clinical results and survival comparable to HA for displaced FN fractures. Hypothesis HA for unstable IT fractures in elderly patients provides clinical results and 1-year survival comparable to HA for displaced FN fractures in the same aging group. Materials and methods We identified 80 patients aged 75 years or older, who underwent cementless bipolar HA for unstable IT fracture (AO/OTA type 31-A2.2/3 and A3.3). Their clinical results and 1-year survival were compared to the matched control group of 80 patients with displaced FN fractures (Garden type 3 and 4) treated with the same procedure. Perioperative results, postoperative complications, and 1-year survival were investigated between the two groups. Functional outcome was assessed by walking status and Harris hip score (HHS) 6 months after surgery. Results Operating time was significantly longer in the IT group than the FN group (97.3 min [50 to 255] vs. 79.3 min [40 to 175], P = 0.016). However, the two groups did not significantly differ regarding perioperative results such as total blood loss, transfusion, intraoperative fracture, length of hospital stay, and postoperative complication. No statistically significant differences in walking status and HHS were observed between the groups. No significant difference in cumulative survival was observed between the two groups (P = 0.836), with a 1-year survival rate of 80% (95% confidence interval [CI], 71.8 to 87.5) in the IT group and 82% (95% CI, 73.1 to 89.4) in the FN group. Conclusion HA for unstable IT fractures in elderly patients showed clinical results and 1-year survival comparable to HA as the treatment of choice for displaced FN fractures in the same aging group. Level of evidence Level III, case-control study.

INTRODUCTION: Contra-lateral hip fractures in elderly patients with a previous hip fracture increase the incidence of complications and socioeconomic burden. The purpose of this study was to identify the risk factors that contribute to the occurrence of contra-lateral hip fracture in elderly patients. MATERIALS AND METHODS: Among 1093 patients treated for a hip fracture, 47 patients sustained a contra-lateral hip fracture. These patients were compared with 141 patients with a unilateral hip fracture (controls). RESULTS: The incidence of contra-lateral hip fracture was 4.3% among the 1093 patients treated for a hip fracture at our institute. A contra-lateral hip fracture occurred within 2 years of initial fracture in 66%, and subsequently, the annual incidence rate decreased. A similar fracture pattern was noted in 70% of patients who sustained an intertrochanteric fracture. In terms of preoperative factors, respiratory disease (OR 2.57, P=0.032) and visual impairment (OR 2.51, P=0.012) were higher in patients with a contra-lateral hip fracture than in controls, and for postoperative factors, the proportions of patients with postoperative delirium (OR 2.91, P=0.022), late onset of rehabilitation (OR 1.05, P=0.023), and poor ambulatory status at 3 months (OR 1.34, P=0.002) were also significantly higher in patients than in controls. CONCLUSIONS: Postoperative delirium and underlying visual impairment and respiratory disease could be risk factors of contra-lateral fracture in elderly patients. Early and active rehabilitation after surgery is important to prevent the occurrence of contra-lateral hip fracture in the elderly. Language: en

Skeletal maturation estimation or bone age assessment of children is a common procedure performed in pediatrics. The bone age assessed by physicians could vary from time to time and the accuracy depends on physicians' experiences. In order to provide a stable and more accurate bone age assessment, computer-assisted bone age assessment systems are employed. Once the epiphyseal fusion has started, the degree of fusion and texture features are analyzed. This paper presents an algorithm to extract and analyze the texture features of the regions of interest of phalanges in hand radiographs at the later stage in order to provide a stable and efficient later stage bone age assessment. The presented algorithm first uses wavelet transform to obtain three detail sub-bands from each region of interest. Then singular value decomposition is employed on each sub-band to extract the maximum likelihood feature, λ. Finally, support vector machine is applied for classification. Experimental results show that this algorithm can provide efficient and accurate later stage bone age assessment.

Hypermobility of the joints is a cardinal feature of Ehlers-Danlos syndrome (EDS) and joint dislocation as a result of no or minor trauma, is a relatively frequent complication of any form, because of ligamentous laxity [1-3]. Hip dislocations are usually the result of high-energy trauma in young adults, with most being posterior [4-6]. Obturator hip dislocations are relatively rare injuries, accounting for no more than 7% of all traumatic hip dislocations [6, 7]. No obturator hip dislocation as a result of minor insult in EDS has yet been reported. We report an unusual case of obturator hip dislocation by minor insult in EDS, complicated by femoral neck fracture and intrapelvic migration of the femoral head occurring during closed reduction, and also suggest management relevant to this rare injury.

Severe patellar infera accompanied by pathologic shortening and fibrosis of the patellar tendon is relatively an uncommmon condition but can cause recalcitrant joint stiffness and limited range of motion after knee surgery or injury. This report presents a case of a 49-year-old male with severe patellar infera and limping due to joint stiffness after three-time knee surgeries. We report a successful outcome along with a finding of the well-healed allograft after the reconstruction of a patellar tendon using Achilles tendon-bone allograft.

Mechanical and tribological properties of engineering and biological materials have been investigated at micro-scale levels from Atomic Force Microscopy (AFM) [1]. Regarding the tribological properties of engineering and biological materials such as the diamond-like carbon (DLC) film [2], the TiN film [3], and the surface of middle finger [4], the significant effect of their surface roughness on the frictional coefficient has been reported. However, the contradictory result that the relationship between the surface roughness and frictional behavior of the self-assembled monolayer (SAM), the silicon ruler, and the metal evaporated (ME) tape [5] is not significant has also been reported. Therefore, the main goal of this study is to investigate the relationships between the surface roughness, the frictional coefficient, and the hardness for both the main wear and the least habitual wear regions of the cobalt-chromium metal head of the hip implant from their measurements using AFM and Hardness Testing Machine. With the additional wear measurements of the metal head, the result of this study can help to understand how the micro-scale surface structure of the metal head affects its wear.Copyright © 2009 by ASME

With an increase of revision total hip arthroplasty (THA), the choice of bearing surface becomes more important. Wear debris by conventional metal-on-polyethylene articulations may cause extensive osteolysis, especially in young patients. We analyzed the clinical and radiographic outcomes after revision THA using third-generation ceramic-on-ceramic bearing surfaces in 42 hips. The mean age of the patients was 48.8 years (32-59 years), and the mean duration of follow-up monitoring was 5.4 years (3.2-8.0 years). At final follow-up examination, the average Harris Hip Score was 91.3. Although minor complications were observed in 6 hips (14.3%), no hips required additional revision surgery. No hip showed radiolucent lines, acetabular cup migration, or osteolysis. Our data show that clinical and radiographic outcomes after revision THA using third-generation ceramic-on-ceramic bearing surfaces are favorable. Ceramic-on-ceramic bearing surfaces can be preferentially considered for revision THA, especially in young patients. Further studies with long-term follow-up data are warranted.

This paper presents a novel image steganographic method that utilizes support vector regression (SVR) to predict the embedded pixel value such that secret data is also embedded into the pixel-value difference between the predicted pixel value and the original pixel value. Due to the significant learning ability in the correlations of training samples by support vector regression, the trained SVR function is obtained by neighboring pixels of the sample pixels to predict the embedded pixel values, and then the proposed scheme uses pixel-value differences to embed the secret data. In the data extraction phase, the proposed scheme uses trained SVR function to predict the embedded pixel value, and the secret data is extracted from pixel-value differences. Experimental results show that SVR is good at learning the correlations of neighboring pixel, and the proposed scheme also has reliable security, high embedding capacity and better image quality for the stego-image.

This paper presents a digital watermarking technology for guaranteeing the database integrity. The proposed scheme based on the fragile watermarking technique, exploits trained support vector regression (SVR) predicting function to distribute the digital watermark over the particular numeric attributes to achieve embedding and detecting watermark by the same SVR predicting function. If the absolute value of the difference between predicted value and attribute value is more than the designed fixed value, like one, then the database content will be tampered with.

Wear-generated particulate debris is the main cause of initiating this destructive process. We present recent advances in understanding of how wear debris causes osteolysis in the aspect of cellular and molecular biological levels. Macrophages, the most important cellular target for wear debris, respond to particle challenge in two distinct ways of pro-inflammatory signaling and inhibition of the protective actions of anti-osteoclastogenic cytokines, finally leading to suppression of osteogenic activity as well as increased osteoclast activity. At a molecular level, such alterations of cellular activities occur through MAP kinase, transcription factors including NF-κB, Wnt/β-catenin signaling and cytokine signaling cascades in various kinds of cells.

Major thrombophilic mutations have been identified as risk factors for nontraumatic osteonecrosis of the femoral head (ONFH) in Caucasians. We asked whether the genetic background of patients with ONFH in the Korean population was similar. We analyzed factor V G1691A mutation (factor V Leiden), prothrombin G20210A mutation, and methylenetetrahydrofolate reductase C677T and A1298C polymorphisms in 71 patients (53 men, 18 women) with ONFH. We classified these patients as 51 alcohol-induced, 18 idiopathic, one steroid-induced, and one dysbaric. We recruited 200 normal control subjects (128 men, 72 women). We used multiplex PCR/restriction fragment length polymorphism for each genotyping. We observed neither factor V Leiden nor prothrombin G20210A mutation. Although methylenetetrahydrofolate reductase A1298C genotypes were not associated with osteonecrosis, methylenetetrahydrofolate reductase C677T variant genotypes increased the risk of ONFH compared with 677CC. Odds ratios of 677CT and 677CT+TT were 2.00 (95% confidence interval, 1.05–3.81) and 1.96 (95% confidence interval, 1.07–3.59), respectively, compared with 677CC. Our data suggest methylenetetrahydrofolate reductase C677T polymorphism plays a role in the pathogenesis of osteonecrosis in the Korean population. It also implies the genetic risk profile of ONFH may differ among ethnic populations.