Influence of the contralateral hip state after total hip arthroplasty on patient-reported outcomes measured with the Forgotten Joint Score-12

PURPOSE

The purpose of this study was to examine the influence of the contralateral hip state on postoperative assessment using the Forgotten Joint Score-12 (FJS-12) in comparison with the McMaster Universities Osteoarthritis Index (WOMAC) and the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ).

METHODS

One hundred and thirty-four hips underwent total hip arthroplasty (THA) between 2014 and 2015. Of these, the subjects were 106 hips with degenerative hip arthrosis as a primary disease for whom initial THA was performed on the affected side. The WOMAC and JHEQ were investigated before surgery and 1 month, 6 months, and 1 year after surgery. The FJS-12 was examined 1 month, 6 months, and 1 year after surgery.

RESULTS

We divided the subjects into three groups based on the state of the contralateral hip, which was not surgically treated in this study: healthy (n = 43), THA (n = 31), and OA (n = 31) groups. One year after surgery, the mean FJS-12 scores in the healthy, THA, and OA groups were 69.1, 52.8, and 68.0 points, respectively. In the THA group, the score was significantly lower than in the healthy and OA group. There were no significant differences in WOMAC and JHEQ scores among the three groups.

CONCLUSIONS

The FJS-12 score in the presence of an arthroplasty on the contralateral side was more markedly influenced by the contralateral hip state compared with that in the presence of contralateral painful OA. This result suggests that it is necessary to understand the characteristics of PROs and utilize them for post-THA assessment.

Malreduction of syndesmosis injury associated with malleolar ankle fracture can be avoided using Weber's three indexes in the mortise view

PURPOSE

Malalignment of syndesmosis is generally associated with a poor outcome, yet occurs at a high rate in malleolar ankle fractures. In this study, we examine whether malreduction of syndesmosis injury associated with malleolar ankle fracture can be avoided using Weber's three indexes in the mortise view.

MATERIALS AND METHODS

Of 156 patients with malleolar ankle fracture who underwent surgery from December 2012 to March 2016 at two medical facilities, 24 patients who received syndesmotic screw fixation were included in the study. Fractures were Danis-Weber types B and C in 8 (8/134, 6.0%) and 16 (16/22, 72.7%) patients, respectively. Using axial computed tomography (CT), we calculated the difference between injured and non-injured sides for each of three parameters: tibiofibular clear space (TFCS), anterior tibiofibular interval (ATF), and fibular rotation (θ^fib). Malreduction was diagnosed if one or more of the three parameters had an abnormal value. Weber's three indexes in the mortise view on the injured side were used to determine whether reduction of syndesmosis was performed successfully. Consistency between the evaluation of reduction of syndesmosis in axial CT images and reevaluation of mortise views was examined by calculation of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

The rate of malreduction of syndesmosis in axial CT images was 29.2% (7/24). Re-evaluation in the mortise view confirmed malreduction of syndesmosis in six of the seven subjects, all of whom also had malreduction based on axial CT images. The one subject in whom malreduction could not be detected in a mortise view showed an abnormal value only for ATF. Use of the mortise view for perioperative diagnosis had a sensitivity of 0.857, specificity of 1.000, PPV of 1.000, and NPV of 0.944.

CONCLUSION

The results of our study show that malreduction of syndesmosis can be avoided by careful interpretation of intraoperative perspective mortise views based on Weber's three indexes. To increase the diagnostic accuracy further, it is important to detect anteroposterior deviation of the fibula in intraoperative lateral views.

Kerboull-type plate in a direct anterior approach for severe bone defects at primary total hip arthroplasty: technical note

Introduction: For cases with extensive acetabular bone defects, we perform surgery combining the Kerboull-type (KT) plate and bone graft through direct anterior approach (DAA) in primary total hip arthroplasty (THA) requiring acetabular reconstruction as minimally invasive surgery. This paper provides the details of the surgical procedure.

Methods: The basic structure of the Kerboull-type plate is a cruciform plate. Since the hook of the Kerboull-type plate has to be applied to the tear drop, a space for it was exposed. The tear drop is located in the anterior lower region in surgery through DAA in supine position. It was also confirmed by fluoroscopy as needed. The bone grafting was performed using an auto- or allogeneic femoral head for bone defects in the weight-bearing region of the hip joint.

Results: Of 563 patients who underwent primary THA between 2012 and 2014, THA using the KT plate through DAA was performed in 21 patients (3.7%). The mean duration of postoperative follow-up was 31.8 months. The mean operative time was 188.4 min, and the mean blood loss was 770 g. The patients became able to walk independently after 2.4 days on average (1–4 days). On clinical evaluation, the modified Harris Hip Score was 45.6 ± 12.4 before surgery, and it was significantly improved to 85.3 ± 8.97 on the final follow-up.

Discussion: DAA is a true intermuscular approach capable of conserving soft tissue. Since it is applied in a supine position, fluoroscopy can be readily used, and it was very useful to accurately place the plate.

Total hip arthroplasty via the direct anterior approach with Kerboull-type acetabular reinforcement device for an elderly female with factor XI deficiency

We present a case of successful and uncomplicated total hip arthroplasty with an acetabular reinforcement device in an elderly patient with hip osteoarthritis already diagnosed with factor XI deficiency, which is a very rare bleeding disorder and at high risk of post-operative haemorrhage, and it poses a substantial challenge to surgeons as a consequence of the specific risks of infection and fixation failure. Moreover, bone fragility in elderly patient increases potential risk of adverse event. Fresh frozen plasma was used to supplement factor XI activity. Importantly, transfusion-transmitted disease such as having factor XI inhibitor was promptly surveyed prior to the supplement since the patient had previous history of the administration of fresh frozen plasma. Under prompt and effective peri-operative haemostasis, rigid implant fixation and rigorous attention to the prevention of infection seem to achieve the best possible outcomes for elderly patients with a bleeding disorder undergoing total hip arthroplasty.

Spontaneous healing of lateral femoral cutaneous nerve injury and improved quality of life after total hip arthroplasty via a direct anterior approach

PURPOSE

How the symptomatology of lateral femoral cutaneous nerve (LFCN) injury changes after total hip arthroplasty (THA) via direct anterior approach (DAA) is not known. Our hypothesis was that the symptoms of LFCN injury after THA via DAA in longer follow-up periods would resolve spontaneously, leading to an improved quality of life (QOL). The aims of this study were to investigate how the symptom LFCN injury changed after DAA-THA, and how those changes affected QOL.

METHODS

We investigated the incidence of LFCN injury after DAA-THA using self-reported questionnaires at two time points (initial survey: August 2014, present survey: August 2015). QOL was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index, the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire, and the Forgotten Joint Score-12 (FJS-12). Types (dysesthesia or hypesthesia) and changes of the symptom were surveyed.

RESULTS

About 122 hips at average12.8 months postoperatively (initial survey), and of those, 89 hips at average 26.2 months postoperatively (present survey) were analyzed. The incidence of LFCN injury decreased significantly, from 31.9% to 11.2% ( p < 0.001). Spontaneous improvement of symptoms was seen in 96%. The difference of FJS-12 between patients with and without LFCN injury at the initial survey disappeared at the present survey. The dysesthesia group showed significant correlations between rate of improvement in LFCN injury and increase of QOL.

CONCLUSION

Most symptoms of LFCN injury resolved spontaneously with longer follow-up periods. In particular, improvement of dysesthesia as a symptom of LFCN injury was associated with better QOL.

Posterior versus direct anterior approach in total hip arthroplasty: difference in patient-reported outcomes measured with the Forgotten Joint Score-12

INTRODUCTION

When the postoperative outcome of primary total hip arthroplasty (THA) was compared with the direct anterior approach (DAA) and the posterior approach (PA), there was no significant difference of the clinical outcome at 6 months to 1 year after surgery in many studies. This study was performed to compare the medium-term outcome of THA via the DAA or PA and clarify which approach achieves better quality of life (QOL).

METHODS

We investigated 61 hips receiving primary THA (30 via DAA and 31 via PA), using hip function scores such as the Harris Hip Score (HHS) and patient-reported outcomes such as the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ), and the Forgotten Joint Score-12 (FJS).

RESULTS

The mean duration of postoperative follow-up was 36.8 months in the DAA group and 40.5 months in the PA group. There was no difference in preoperative or postoperative HHS between the two groups. Although there was no difference of postoperative WOMAC and JHEQ, the postoperative FJS-12 score was significantly higher in the DAA group than in the PA group (75.2 ± 15.9 versus 60.1 ± 24.4, p = 0.01).

CONCLUSION

When forgetting the artificial joint in daily life is the target, better QOL can be achieved by performing THA via the DAA.

Early glottic squamous cell carcinoma: Predictive value of MR imaging for the rate of 5-year local control with radiation therapy

Purpose: To evaluate MR findings in early (T1 and T2 stages) glottic carcinomas and the predictive value of MR imaging for the rate of 5-year local control with radiation therapy.

Material and Methods: Eighty-three patients with early glottic carcinomas were prospectively examined with MR at 1.5 T. MR investigation included unenhanced T1-weighted, T2-weighted, dynamic and contrast-enhanced T1-weighted images. Three patients with presumed advanced diseases on MR were initially treated with total laryngectomy and were excluded from the study. The remaining 80 patients were treated with radiation therapy with curative intent. Tumor detectability, size and relationship to the thyroid cartilage were determined on MR images. The MR findings were then correlated with the rate of local control.

Results: Forty-eight of 80 lesions (60%) were detected on MR imaging. All detected lesions but 1 demonstrated increased signal on T2-weighted images. The lesions were best delineated on dynamic images (statistically significant). The 5-year local control rate with radiation therapy was 72%. Univariate analysis revealed clinical T stage, MR detectability, tumor size and relationship to the thyroid cartilage as significant predictors. Multivariate analysis revealed that the relationship to the thyroid cartilage was an independent factor.

Conclusion: MR provides prognostic information about the results of definitive radiation therapy. To evaluate the tumor extension in lesions detected on precontrast MR images, contrast-enhanced dynamic images should be obtained.

New classification focusing on the relationship between the attachment of the iliofemoral ligament and the course of the fracture line for intertrochanteric fractures

PURPOSE

There are various types of intertrochanteric fractures that are unstable pertrochanteric fractures of the hip. The aim of this study was to develop a systematic and comprehensive classification of intertrochanteric fractures.

MATERIALS AND METHODS

This study enrolled 74 patients with intertrochanteric fractures treated by us between 2012 and 2015. The fractures were classified using 3D-CT images taken immediately after the fractures occurred based on the course of the lateral fracture line (LFL) that extends through the lateral femoral cortex distal to the vastus ridge of the greater trochanter in the intertrochanteric area. Furthermore, the presence or absence of additional typical fractures was also studied. Then, 4 orthopedic specialists examined the 3D-CT images of 20 patients randomly selected from the 74 patients to evaluate both the inter-rater and intra-rater agreement levels.

RESULTS

Intertrochanteric fractures were classified into three types according to the LFL patterns. Type I (41.9%), the Lateral Wall Pattern, has a LFL that extends towards the lateral fiber bundle attachment area of the iliofemoral ligament. Type II (24.3%), the Transverse Pattern, has a LFL that extends towards the medial bundle attachment area. Type III (33.8%), the Reverse Oblique Pattern, has a LFL that extends between the lateral and medial fiber bundle area of the iliofemoral ligament. Each type showed characteristic displacement and was associated with various combinations of typical fractures (fracture across the intertrochanteric line, posteromedial fragment, including the lesser trochanter, posterolateral fragment posterior to the femoral greater trochanter, and banana-shaped big fragment, including both the greater trochanter and the lesser trochanter). The mean κ values for the interobserver and intraobserver agreement levels were 0.77 (0.70-0.85) and 0.76 (0.70-0.85), respectively, which were considered substantial agreement levels.

CONCLUSION

We believe our new classification is a useful communication tool for medical professionals in the diagnosis of fractures.

Does the Canal Fill Ratio and Femoral Morphology of Asian Females Influence Early Radiographic Outcomes of Total Hip Arthroplasty With an Uncemented Proximally Coated, Tapered-Wedge Stem?

BACKGROUND

Noncement femoral fixation in total hip arthroplasty (THA) has been gaining popularity. However, owing to the numerous varieties of uncemented stems and differing types of femoral stem morphology, it is unclear whether the clinical outcomes of all uncemented stems are equal. The aim of this study was to investigate the relationships between canal fill ratio and femoral morphology and early radiologic outcomes in Japanese patients who underwent THA with an uncemented proximally hydroxyapatite-coated, tapered-wedge stem.

METHODS

We retrospectively reviewed 103 patients who had undergone THA using a single proximally coated tapered-wedge stem. The relationships between canal fill ratio and femoral morphology and early radiologic outcomes after THA with those stem were investigated.

RESULTS

Eighty-one hips were analyzed after inclusion and exclusion criteria were applied. Failed osteointegration proximally was observed in 4 hips (4.9%). Canal flare index was significantly greater in hips with failed osteointegration than in those with successful osteointegration (P = .009). Distal hypertrophy was observed in 14 hips (17.3%). Proximal-distal matching ratio was significantly lower in hips with distal hypertrophy than in those without (P = .01). Canal fill ratio at 2 cm above the lesser trochanter was smaller in hips with failed osteointegration and distal hypertrophy than in those without (P = .02).

CONCLUSION

Suboptimal radiologic changes were seen with greater distal fill with smaller proximal fill and with a narrow femoral canal. It is important to select the stem that can achieve the original concept of intended primary and secondary fixation areas.

High-Convexity Tightness Predicts the Shunt Response in Idiopathic Normal Pressure Hydrocephalus

BACKGROUND AND PURPOSE

Although neuroimaging plays an important role in the diagnosis of idiopathic normal pressure hydrocephalus, its predictive value for response to shunt surgery has not been established. The purpose of the current study was to identify neuroimaging markers that predict the shunt response of idiopathic normal pressure hydrocephalus.

MATERIALS AND METHODS

Sixty patients with idiopathic normal pressure hydrocephalus underwent presurgical brain MR imaging and clinical evaluation before and 1 year after shunt surgery. The assessed MR imaging features included the Evans index, high-convexity tightness, Sylvian fissure dilation, callosal angle, focal enlargement of the cortical sulci, bumps in the lateral ventricular roof, and deep white matter and periventricular hyperintensities. The idiopathic normal pressure hydrocephalus grading scale total score was used as a primary clinical outcome measure. We used measures for individual symptoms (ie, the idiopathic normal pressure hydrocephalus grading scale subdomain scores, such as gait, cognitive, and urinary scores), the Timed Up and Go test, and the Mini-Mental State Examination as secondary clinical outcome measures. The relationships between presurgical neuroimaging features and postoperative clinical changes were investigated by using simple linear regression analysis. To identify the set of presurgical MR imaging features that best predict surgical outcomes, we performed multiple linear regression analysis by using a bidirectional stepwise method.

RESULTS

Simple linear regression analyses demonstrated that presurgical high-convexity tightness, callosal angle, and Sylvian fissure dilation were significantly associated with the 1-year changes in the clinical symptoms. A multiple linear regression analysis demonstrated that presurgical high-convexity tightness alone predicted the improvement of the clinical symptoms 1 year after surgery.

CONCLUSIONS

High-convexity tightness is a neuroimaging feature predictive of shunt response in idiopathic normal pressure hydrocephalus.

Greater trochanter chip fractures in the direct anterior approach for total hip arthroplasty

BACKGROUND

The direct anterior approach (DAA) for the treatment of total hip arthroplasty (THA) has gained popularity in recent years. Chip fractures of the greater trochanter are frequently seen, but the risk factors for such fractures are unknown. The study aimed to identify the risk factors for chip fractures in patients undergoing primary THA by the DAA during the surgeons' learning curve.

MATERIALS AND METHODS

From November 2011 to April 2015, the first experiences of three surgeons who performed 120 THAs by the DAA (120 hips; 40 cases per beginner surgeon) were included. The incidence of chip fracture of the greater trochanter, the size of the greater trochanter as measured by computed tomography, and the patients' characteristics were retrospectively investigated.

RESULTS

After exclusion of 11 hips, the remaining 109 hips were investigated. Chip fracture of the greater trochanter was identified in 32 hips (29.4 %). Univariate analysis with and without fractures showed that the width and depth of the greater trochanter were statistically significant risk factors (p = 0.02 and p < 0.001, respectively). Multivariate analysis using a logistic regression model demonstrated that the depth of the greater trochanter was an independent risk factor for chip fracture of the greater trochanter (OR 1.725; 95 % CI 1.367-2.177; p < 0.001).

CONCLUSION

The size of the greater trochanter was identified as a risk factor for chip fracture of the greater trochanter. Novice surgeons should pay attention to the size of the greater trochanter when performing THA by the DAA.

Benefit and risk in short term after total hip arthroplasty by direct anterior approach combined with dual mobility cup

PURPOSE

No previous reports have described the benefits and risks associated with the dual mobility cup (DMC) in primary THA via direct anterior approach (DAA). The aim of this study was to compare the safety and rate of early postoperative complication of the DAA with the DMC for THA with those of the DAA with a single standard cup, and to investigate the influence of the learning curve of the use of DMC on intra- and perioperative outcomes.

METHODS

We retrospectively investigated 60 hips treated in the single-DAA group and 60 hips treated in the dual-DAA group. A primary/secondary outcome variable was the presence of any intra- or perioperative complication within the first 6 months/the operative time and hip function at 6 months postoperatively. We also analyzed influence of the learning curve of the use of DMC on intra- and perioperative outcomes.

RESULTS

No intraoperative complications were observed in either group. One anterior dislocation and one periprosthetic hip fracture were occurred in the single-DAA group. The surgical times in the single-DAA and dual-DAA groups were 112.0 ± 20.9 and 121.0 ± 26.9 min (p < 0.001). There was no significant difference in the 6-month postoperative hip function scores between the two groups. There was no influence of the learning curve of the use of DMC on intra- and perioperative outcomes.

CONCLUSION

We have demonstrated the short-term safety and lack of inferiority of using the DMC in the DAA compared with the standard single mobility cup.

Acute Calcific Tendinitis of the Rectus Femoris: A Case Series

Introduction:

Periarticular calcific tendinitis is a common cause of Orthopedic outpatient referral. Calcific tendinitis of the rectus femoris, however, is very rare and not well known. Due to its rarity, correct diagnosis and prompt treatment are not fully understood.

Case Report:

Two females (38 and 40 years old) of acute calcific tendinitis of the rectus femoris with the good clinical course without any operative treatment were presented. The pain was managed with oral non-steroidal antiinflammatory drugs and/or local steroid injection. Interval radiographic assessment showed complete resorption of the calcification.

Conclusion:

Establishing the correct diagnosis and initiating prompt treatment are shown to be important in achieving resolution of symptoms and in avoiding unnecessary investigations.

Catalytic discrimination between formyl groups in regio- and stereoselective intramolecular cross-aldol reactions

Catalytic discrimination between inequivalent formyl groups was achieved using an aniline-type acid-base catalyst for the regio-, diastereo-, and enantioselective intramolecular cross-aldol reactions of enolizable dials. Although l-proline gave a mixture of the regio- and stereoisomeric products in the presence of an N-containing 1,6-dial, the aniline-type catalyst afforded anti-3,4-disubstituted pyrrolidine in high regio-, and stereoselectivity beyond the background reaction, which led to the regioisomeric 2,3-disubstituted products. The mild reactivity of the aniline-type amine facilitated catalytic discrimination between the inequivalent formyl groups. Kinetic isotope effect studies and reductive amination experiments suggested that the regioselectivity was controlled under the enamine-forming steps.

Significance of histologic pattern of carcinoma and sarcoma components on survival outcomes of uterine carcinosarcoma

BACKGROUND

To examine the effect of the histology of carcinoma and sarcoma components on survival outcome of uterine carcinosarcoma.

PATIENTS AND METHODS

A multicenter retrospective study was conducted to examine uterine carcinosarcoma cases that underwent primary surgical staging. Archived slides were examined and histologic patterns were grouped based on carcinoma (low-grade versus high-grade) and sarcoma (homologous versus heterologous) components, correlating to clinico-pathological demographics and outcomes.

RESULTS

Among 1192 cases identified, 906 cases were evaluated for histologic patterns (carcinoma/sarcoma) with high-grade/homologous (40.8%) being the most common type followed by high-grade/heterologous (30.9%), low-grade/homologous (18.0%), and low-grade/heterologous (10.3%). On multivariate analysis, high-grade/heterologous (5-year rate, 34.0%, P = 0.024) and high-grade/homologous (45.8%, P = 0.017) but not low-grade/heterologous (50.6%, P = 0.089) were independently associated with decreased progression-free survival (PFS) compared with low-grade/homologous (60.3%). In addition, older age, residual disease at surgery, large tumor, sarcoma dominance, deep myometrial invasion, lymphovascular space invasion, and advanced-stage disease were independently associated with decreased PFS (all, P < 0.01). Both postoperative chemotherapy (5-year rates, 48.6% versus 39.0%, P < 0.001) and radiotherapy (50.1% versus 44.1%, P = 0.007) were significantly associated with improved PFS in univariate analysis. However, on multivariate analysis, only postoperative chemotherapy remained an independent predictor for improved PFS [hazard ratio (HR) 0.34, 95% confidence interval (CI) 0.27-0.43, P < 0.001]. On univariate analysis, significant treatment benefits for PFS were seen with ifosfamide for low-grade carcinoma (82.0% versus 49.8%, P = 0.001), platinum for high-grade carcinoma (46.9% versus 32.4%, P = 0.034) and homologous sarcoma (53.1% versus 38.2%, P = 0.017), and anthracycline for heterologous sarcoma (66.2% versus 39.3%, P = 0.005). Conversely, platinum, taxane, and anthracycline for low-grade carcinoma, and anthracycline for homologous sarcoma had no effect on PFS compared with non-chemotherapy group (all, P > 0.05). On multivariate analysis, ifosfamide for low-grade/homologous (HR 0.21, 95% CI 0.07-0.63, P = 0.005), platinum for high-grade/homologous (HR 0.36, 95% CI 0.22-0.60, P < 0.001), and anthracycline for high-grade/heterologous (HR 0.30, 95% CI 0.14-0.62, P = 0.001) remained independent predictors for improved PFS. Analyses of 1096 metastatic sites showed that carcinoma components tended to spread lymphatically, while sarcoma components tended to spread loco-regionally (P < 0.001).

CONCLUSION

Characterization of histologic pattern provides valuable information in the management of uterine carcinosarcoma.

Safety in early experience with a direct anterior approach using fluoroscopic guidance with manual leg control for primary total hip arthroplasty: a consecutive one hundred and twenty case series

BACKGROUND AND PURPOSE

An encouraging result with direct anterior approach (DAA) is attractive for both patients and surgeons. However, the risks associated with beginning to use DAA require further analysis of the learning curve and better countermeasures to ensure safety. We ask whether the complication rate in the DAA by the inexperienced surgeon could be decreased with specific countermeasures. Our hypothesis was that the complication rate would be low even in early phase of the learning curve using the DAA with these particular countermeasures.

PATIENTS AND METHODS

We investigated a consecutive series of 120 primary THA using the DAA with four specific countermeasures; 1) defined exclusion criteria for DAA; 2) no positioning table; 3) use of fluoroscopy as much as required; and 4) having an experienced assistant for DAA (one who has performed the procedure in more than 100 cases). The operative time, the time of fluoroscopic use during the operation, intra and post-operative complications, re-operation for any reason, and cup and stem alignment were investigated.

RESULTS

Although the operation times were similar, the duration of fluoroscopy decreased with surgeons' experience. There were no intra-operative complications and no re-operations for any reason. One anterior dislocation was observed in one patient. The mean cup inclination and anteversion angle was 39.7° ± 7.6° and 30.3° ± 7.6°; 43.3 % of stems were positioned in flexion, 55.8 % in the neutral position on the lateral view.

CONCLUSION

We demonstrated a lower complication rate during our early experience with the DAA using four countermeasures. Using these countermeasures for the first 40 cases may be useful for surgeons who are considering DAA.

Candidate Resonant Tetraneutron State Populated by the ^{4}He(^{8}He,^{8}Be) Reaction

A candidate resonant tetraneutron state is found in the missing-mass spectrum obtained in the double-charge-exchange reaction ^{4}He(^{8}He,^{8}Be) at 186  MeV/u. The energy of the state is 0.83±0.65(stat)±1.25(syst)  MeV above the threshold of four-neutron decay with a significance level of 4.9σ. Utilizing the large positive Q value of the (^{8}He,^{8}Be) reaction, an almost recoilless condition of the four-neutron system was achieved so as to obtain a weakly interacting four-neutron system efficiently.

Importance of the spinopelvic factors on the pelvic inclination from standing to sitting before total hip arthroplasty

PURPOSE

Dislocation after total hip arthroplasty (THA) is a major postoperative complication. Even if the cup is in the safe zone, dislocation caused by implant impingement may occur during postural changes. The aim of the present study was to investigate the spinopelvic factors that influence pelvic inclination changes from standing to sitting in patients with hip diseases who were candidates for THA.

METHODS

74 patients who underwent primary THA were included according to our criteria. The analysis of the sagittal balance of the spinopelvic complex was performed on standing and sitting lateral radiographs. Pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis angle (LLA), thoracic kyphosis angle (TK), and sagittal vertical axis (SVA) were measured. The differences between the standing and sitting positions regarding the spinal and pelvic parameters were analyzed. Correlations between the variables of the spinopelvic parameters were examined using Spearman's rank correlation coefficient.

RESULTS

The changes in SVA, TK, LLA, SS, PT, and PI from the standing to sitting positions, respectively, were -3.9 ± 48.2 mm, -0.1° ± 6.4°, 21.4° ± 17.7°, 22.2° ± 12.2°, -22.3° ± 13.2°, and 0.4° ± 6.9°. The lumbar lordosis was reduced and pelvic rotation was extended from the standing to the sitting position. The correlation coefficient between the change in the SS and that in the LLA was 0.72 (p < 0.0001). The correlation coefficient between the change in PT and that in the LLA was -0.68 (p < 0.0001).

CONCLUSIONS

The change in pelvic inclination from standing to sitting is strongly related to the mobility of the lumbar spine in patients with hip diseases.

Lateral femoral cutaneous nerve injury with the direct anterior approach for total hip arthroplasty

PURPOSE

Although injury of the lateral femoral cutaneous nerve (LFCN) is a known complication after total hip arthroplasty (THA) via the direct anterior approach (DAA), the impact of this complication on postoperative quality of life (QOL) is unclear. This study aims to investigate the incidence of LFCN injury after DAA for THA, and to determine the impact of LFCN injury on QOL and hip function.

METHODS

We prospectively investigated 122 hips operated upon using the DAA regarding the incidence of LFCN injury using self-reported questionnaires, hip functional scores such as the Harris Hip Score (HHS) and the Japanese Orthopaedic Association (JOA) score, and patient-reported outcomes such as the Western Ontario and McMaster Universities Osteoarthritis Index, the Japanese Orthopaedic Association Hip disease Evaluation Questionnaire (JHEQ), and the Forgotten Joint Score-12 (FJS).

RESULTS

LFCN injury was seen in 39 hips (31.9 %). In affected hips, the leading symptom was hypo-aesthesia (46.2 %), followed by tingling or jolt-like sensation (28.2 %). There was no difference in the HHS and JOA score between those with LFCN injury and those without. There was a significant difference in the FJS-12 between the two groups (50.9 ± 25.3 for hips with LFCN injury vs 64.3 ± 25.7 without, p = 0.01). There was a non-significant tendency for patients with LFCN injury to have a lower JHEQ than those without (63.6 ± 19.6 for hips with LFCN injury vs 70.8 ± 22.9 without, p = 0.13).

CONCLUSIONS

The incidence of LFCN injury decreased QOL but not hip function after DAA for THA.

Validation study of the Forgotten Joint Score-12 as a universal patient-reported outcome measure

PURPOSE

The Forgotten Joint Score-12 (FJS-12) is for patients to forget their artificial joint and is reportedly a useful patient-reported outcome tool for artificial joints. The purpose of this study was to determine whether the FJS-12 is as useful as the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) or the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) in Japan.

METHODS

All patients who visited our hospital's hip joint specialists following unilateral THA from August 2013 to July 2014 were evaluated. Medical staff members other than physicians administered three questionnaires. Items evaluated were (1) the reliability of the FJS-12 and (2) correlations between the FJS-12 and the total and subscale scores of the WOMAC or JHEQ.

RESULTS

Of 130 patients, 22 were excluded. Cronbach's α coefficient was 0.97 for the FJS-12. The FJS-12 showed a significantly lower score than the WOMAC or JHEQ (p < 0.01). The FJS-12 was moderately correlated with the total WOMAC score (r = 0.522) and its subscale scores for "stiffness" (r = 0.401) and "function" (r = 0.539) and was weakly correlated with the score for "pain" (r = 0.289). The FJS-12 was favorably correlated with the total JHEQ score (r = 0.686) and its subscale scores (r = 0.530-0.643).

CONCLUSION

The FJS-12 was correlated with and showed reliability similar to that of the JHEQ and WOMAC. The FJS-12, which is not affected by culture or lifestyle, may be useful in Japan.

Inadequate management for secondary fracture prevention in patients with distal radius fracture by trauma surgeons

We evaluated the secondary fracture prevention in 1445 patients with distal radius fracture by trauma surgeons. The rate of patients with distal radius fracture who underwent bone mineral density (BMD) examination was low, suggesting that appropriate treatment for osteoporosis by trauma surgeons is not performed at present.

INTRODUCTION

To clarify the status of osteoporosis interventions after distal radial fractures by trauma surgeons who play the main role in treatment for these fractures, we performed a survey involving multiple institutions in Japan.

METHODS

We asked 155 board members of the Japanese Society for Fracture Repair for their cooperation and performed a survey in 48 institutions with which members who gave cooperation were affiliated. The subjects consisted of consecutive patients with distal radial fractures occurring between January and December 2012. The presence or absence of a diagnosis of osteoporosis and bone mineral density examination after fracture was investigated.

RESULTS

A total of 1445 patients with distal radial fractures were evaluated in this study. BMD examination for diagnosis and treatment for osteoporosis after fracture was performed respectively in 126 (8.7 %) and 193 (13.4 %) of 1445 patients. Treatment for osteoporosis was performed in 93 (73.8 %) of 126 patients who underwent BMD examination after fracture and 100 (8.2 %) of 1219 who did not undergo BMD examination. Of the 126 patients who underwent BMD examination after fracture, 89 showed a BMD <80 % of the young adult mean as a criterion for the initiation of drug treatment for osteoporosis in Japan and 77 (86.5 %) of the 89 patients were treated with drugs.

CONCLUSIONS

The rate of patients with distal radial fractures who underwent BMD examination was low, suggesting that appropriate treatment for osteoporosis by trauma surgeons is not performed at present.

The incidence of and risk factors for developing atypical femoral fractures in Japan

The long-term treatment with anti-resorptive drugs for osteoporotic patients is suggested to be associated with an increase in atypical femoral fractures (AFFs). However, their incidence, patient characteristics, and risk factors have not been fully elucidated especially in Asian countries. This retrospective observational cohort study found fourteen AFFs in ten patients (four bilateral fractures) among 2,238 hip and femoral shaft fractures treated in our associated hospitals between 2005 and 2010; this incidence (0.63%) was similar to Caucasians. Of the ten patients with AFFs, nine (90%) and six (60%) were using bisphosphonates (BPs) and glucocorticoids (GCs), respectively, compared to 14.3 and 8.6% for patients with typical femoral fractures who were using these agents. As comorbid conditions, five patients had collagen disease (CD) and two had diabetes. A fracture location-, age- and gender-matched (1:3) case-control study revealed that administration of BPs, GCs, and suffering from collagen disease (CD) were significant risk factors for developing AFFs [odds ratios 36.0 (95% confidence intervals 3.8-342.2), 13.0 (2.3-74.1) and 9.0 (1.6-50.3), respectively]. Interestingly, all of the patients with atypical subtrochanteric femoral fractures, defined as those within 5 cm of the lesser trochanter, were taking GCs due to CD, and the age of these patients (average of 54.8 years) was significantly younger than those with atypical diaphyseal femoral fractures (average of 77.2 years, p < 0.05). In conclusion, the incidence of AFFs in the Japanese population was similar to that of Caucasians, and taking BPs and GCs and suffering from CD were risk factors for developing AFFs.

IFN-γ from lymphocytes induces PD-L1 expression and promotes progression of ovarian cancer

BACKGROUND

PD-L1 (programmed cell death 1 ligand 1) on tumour cells suppresses host immunity through binding to its receptor PD-1 on lymphocytes, and promotes peritoneal dissemination in mouse models of ovarian cancer. However, how PD-L1 expression is regulated in ovarian cancer microenvironment remains unclear.

METHODS

The number of CD8-positive lymphocytes and PD-L1 expression in tumour cells was assessed in ovarian cancer clinical samples. PD-L1 expression and tumour progression in mouse models under conditions of altering IFN-γ signals was assessed.

RESULTS

The number of CD8-positive cells in cancer stroma was very high in peritoneally disseminated tumours, and was strongly correlated to PD-L1 expression on the tumour cells (P<0.001). In mouse models, depleting IFNGR1 (interferon-γ receptor 1) resulted in lower level of PD-L1 expression in tumour cells, increased the number of tumour-infiltrating CD8-positive lymphocytes, inhibition of peritoneal disseminated tumour growth and longer survival (P=0.02). The injection of IFN-γ into subcutaneous tumours induced PD-L1 expression and promoted tumour growth, and PD-L1 depletion completely abrogated tumour growth caused by IFN-γ injection (P=0.01).

CONCLUSIONS

Interferon-γ secreted by CD8-positive lymphocytes upregulates PD-L1 on ovarian cancer cells and promotes tumour growth. The lymphocyte infiltration and the IFN-γ status may be the key to effective anti-PD-1 or anti-PD-L1 therapy in ovarian cancer.

Higher reliability and validity of Baba classification with computerised tomography imaging and implant information for periprosthetic femoral fractures

PURPOSE

Baba classification for periprosthetic femoral fracture focuses on the positional relationship between the implant design and fracture site. The objective of this study was to investigate whether the addition of CT images and implant information to plain radiograms increases the reliability of Baba classification to a level higher than that of Vancouver classification.

METHODS

Twenty patients were randomly selected from 61 patients with periprosthetic femoral fracture between 2009 and 2014. After Vancouver and Baba classifications were fully explained to six orthopedic surgeons (three experts and three non-experts), plain radiograms, CT imaging and implant information at the time of injury were presented, and the inter- and intra-observer reliability based on the Vancouver and Baba classifications and accuracy rates of stem stability were investigated.

RESULTS

When interobserver reliability was made based on only radiograms, the mean κ value of Baba classification-based judgments made by the experts was 0.76, and those of Vancouver classification-based judgments made by the experts was 0.41. When interobserver reliability was made based on the radiograms and CT images and implant information, the mean κ value of Baba classification-based judgments made by the experts was 0.94, and those of Vancouver classification-based judgments were 0.48. Intra-observer reliability of Baba classification was 0.81 in the experts. Validity analysis showed 95.0% agreement within all subgroups.

CONCLUSIONS

Reliability and validity of Baba classification was improved when additional information was given. We believe that this new classification is useful to establish a therapeutic strategy for femoral fractures around the stem.

Pulmonary Aluminosis Diagnosed with In-air Microparticle Induced X-ray Emission Analysis of Particles

We herein present a case of pulmonary aluminosis diagnosed with in-air microparticle induced X-ray emission (in-air micro-PIXE) analysis. The diagnosis of pulmonary aluminosis was supported by the occupational exposure to aluminum, ground glass opacity and ill-defined centrilobular nodular opacities seen in high resolution CT, and respiratory bronchioles accompanied by pigmented dust by histological examination by in-air micro-PIXE analysis of the lung tissues. The possibility of developing this rare condition should not be underestimated in workers at high-risk jobs. This is an important report showing the usefulness of an in-air micro-PIXE analysis for the early diagnosis of aluminosis.

The fracture sites of atypical femoral fractures are associated with the weight-bearing lower limb alignment

Atypical femoral fractures (AFFs) are stress-related fractures that are speculated to associate with long-term treatment with bisphosphonates for osteoporosis. A history of AFF is a high risk factor for the development of a subsequent AFF in the same location of the contralateral femur, suggesting that a patient's individual anatomical factor(s) are related to the fracture site of AFFs. In this study, we investigated the radiographs of fourteen AFFs (four bilateral fractures among ten patients) treated at six hospitals associated with our university between 2005 and 2010. The fracture site and standing femorotibial angle (FTA), which reflects the mechanical axis of the lower limb, were measured on weight-bearing lower limb radiographs. The fracture site and FTA of patients with typical femoral fractures (TFF) were compared to those of patients with AFFs. The correlations were examined using Spearman's rank correlation coefficients. The fracture locations in the femora were almost the same in the patients with bilateral AFFs. There was a positive correlation between the fracture site and the standing FTA in the patients with AFFs (r=0.82, 95% confidence interval; 0.49 to 0.94), indicating that the larger the standing FTA (varus alignment), the more distal the site of the fracture in the femur. The FTA of the patients with atypical diaphyseal femoral fracture were significantly larger compared to that of those with not only atypical subtrochanteric fractures but also TFFs. In conclusion, the fracture sites of AFFs are associated with the standing lower limb alignment, while those of TFFs are not.

Multi-drug-resistant Staphylococcus aureus and future chemotherapy

Staphylococcus (S.) aureus silently stays as our natural flora, and yet sometimes threatens our life as a tenacious pathogen. In addition to its ability to outwit our immune system, its multi-drug resistance phenotype makes it one of the most intractable pathogenic bacteria in the history of antibiotic chemotherapy. It conquered practically all the antibiotics that have been developed since 1940s. In 1961, the first MRSA was found among S. aureus clinical isolates. Then MRSA prevailed throughout the world as a multi-resistant hospital pathogen. In 1997, MRSA strain Mu50 with reduced susceptibility to vancomycin was isolated. Vancomycin-intermediate S. aureus (VISA), so named according to the CLSI criteria, was the product of adaptive mutation of S. aureus against vancomycin that had long been the last resort to MRSA infection. Here, we describe the genetic basis for the remarkable ability of S. aureus to acquire multi-antibiotic resistance, and propose a novel paradigm for future chemotherapy against the multi-resistant pathogens.

New classification focusing on implant designs useful for setting therapeutic strategy for periprosthetic femoral fractures

PURPOSE

In periprosthetic femoral fractures, our hypothesis was that when the bone and implant are stable, the fracture does not occur at the biologic or cement fixation regions but occurs at the no fixation region. The aim of this study was to investigate the validity of our new classification for periprosthetic femoral fractures and compare reliability of radiographic evaluation for implant stability between our classification and the Vancouver classification.

PATIENTS AND METHODS

Sixty-six patients with periprosthetic femoral fracture were operatively treated by us between 2005 and 2013. We investigated the sensitivity and specificity of our new classification with actual implant stability. Twenty patients were randomly selected from 66 patients. After fully explaining the Vancouver and our new classification to four orthopaedic surgeons, plain radiographs acquired in two directions at the time of injury were presented, and the interobserver reliability based on the two classifications and accuracy rates of stem stability were investigated.

RESULTS

The specificity of the new classification was 89%, and sensitivity was 94%. The positive and negative predictive values were 84% and 96%, respectively. Interobserver agreement was separately assessed among all possible pairs of orthopaedic surgeons. The κ values for the Vancouver and the new classification were 0.36 (0.19-0.49) and 0.76 (0.66-1.0), respectively.

CONCLUSIONS

Our classification is based on a completely new concept and was prepared to overcome periprosthetic femoral fracture failures by objective evaluation. We believe this new classification is useful to establish a therapeutic strategy for femoral fractures around the stem.

Dynamic wavelength conversion in copropagating slow-light pulses

Dynamic wavelength conversion (DWC) is obtained by controlling copropagating slow-light signal and control pulse trajectories. Our method is based on the understanding that conventional resonator-based DWC can be generalized, and is linked to cross-phase modulation. Dispersion-engineered Si photonic crystal waveguides produce such slow-light pulses. Free carriers generated by two-photon absorption of the control pulse dynamically shift the signal wavelength. Matching the group velocities of the two pulses enhances the shift, elongating the interaction length. We demonstrate an extremely large wavelength shift in DWC (4.9 nm blueshift) for the signal wavelength. Although DWC is similar to the Doppler effect, we highlight their essential differences.

Application of supernodal sparse factorization and inversion to the estimation of (co)variance components by residual maximum likelihood

We demonstrated that supernodal techniques were more efficient than traditional methods for factorization and inversion of a coefficient matrix of mixed model equations (MME), which are often required in residual maximum likelihood (REML). Supernodal left-looking and inverse multifrontal algorithms were employed for sparse factorization and inversion, respectively. The approximate minimum degree or multilevel nested dissection was used for ordering. A new computer package, Yet Another MME Solver (YAMS), was developed and compared with FSPAK with respect to computing time and size of temporary memory for 13 test matrices. The matrices were produced by fitting animal models to dairy data and by using simulations from sire, sire-maternal grand sire, maternal and dominance models for phenotypic data and animal model for genomic data. The order of matrices ranged from 32,840 to 1,048,872. The YAMS software factorized and inverted the matrices up to 13 and 10 times faster than FSPAK, respectively, when an appropriate ordering strategy was applied. The YAMS package required at most 282 MB and 512 MB of temporary memory for factorization and inversion, respectively. Processing time per iteration in average information REML was reduced, using YAMS. The YAMS package is freely available on request by contacting the corresponding author.

Bipolar hemiarthroplasty for femoral neck fracture using the direct anterior approach

AIM: To evaluate whether walking ability recovers early after bipolar hemiarthroplasty (BHA) using a direct anterior approach.

METHODS: Between 2008 and 2010, 81 patients with femoral neck fracture underwent BHA using the direct anterior approach (DAA) or the posterior approach (PA). The mean observation period was 36 mo. The age, sex, body mass index (BMI), time from admission to surgery, length of hospitalization, outcome after discharge, walking ability, duration of surgery, blood loss and complications were compared.

RESULTS: There was no significant difference in the age, sex, BMI, time from admission to surgery, length of hospitalization, outcome after discharge, duration of surgery and blood loss between the two groups. Two weeks after the operation, assistance was not necessary for walking in the hospital in 65.0% of the patients in the DAA group and in 33.3% in the PA group (P < 0.05). As for complications, fracture of the femoral greater trochanter developed in 1 patient in the DAA group and calcar crack and dislocation in 1 patient each in the PA group.

CONCLUSION: DAA is an approach more useful for BHA for femoral neck fracture in elderly patients than total hip arthroplasty in terms of the early acquisition of walking ability.

Ultrafast slow-light tuning beyond the carrier lifetime using photonic crystal waveguides

We demonstrate ultrafast delay tuning of a slow-light pulse with a response time <10 ps. This is achieved using two types of slow light: dispersion-compensated slow light for the signal pulse, and low-dispersion slow light to enhance nonlinear effects of the control pulse. These two types of slow light are generated simultaneously in Si lattice-shifted photonic crystal waveguides, arising from flat and straight photonic bands, respectively. The control pulse blueshifts the signal pulse spectrum, through dynamic tuning caused by the plasma effect of two-photon-absorption-induced carriers. This changes the delay by up to 10 ps only when the two pulses overlap within the waveguide and enables ultrafast tuning that is not limited by the carrier lifetime. Using this, we succeeded in tuning the delay of one target pulse within a pulse train with 12 ps intervals.