Large deformity correction in medial open-wedge high tibial osteotomy may cause degeneration of patellofemoral cartilage: A retrospective study

To evaluate retrospectively any association between the degree of deformity correction by medial open-wedge high tibial osteotomy (HTO) and patellofemoral joint degeneration. We hypothesized that development of patellofemoral joint degeneration depended on the degree of intraoperative deformity correction.Fifty-seven patients who underwent medial open-wedge HTO for treatment of osteoarthritis in one knee were included in this study. Knees were classified into degeneration (D) and non-degeneration (ND) groups according to worsening of the patellar and/or femoral trochlear cartilage at the time of hardware removal (D group, 27 knees) and no degeneration or improvement (ND group, 30 knees). We compared pre- to post-surgery change in hip-knee-ankle angle (HKA) and medial-proximal-tibial angle (MPTA), open-wedge HTO correction angle, and arthroscopic findings between groups.Mean age, height, weight, and body mass index were 54.1 ± 9.9 years, 160.4 ± 8.7 cm, 66.4 ± 12.1 kg, and 25.7 ± 3.3 kg/m, respectively. Change in both HKA and MPTA differed significantly between groups. The MPTA cut-off values to predict patellofemoral degeneration were determined to be 10°, associated with an AUC of 0.75 (95% confidence interval [CI] 0.62-0.87).This study evaluated retrospectively the effect of the correction angle during medial open-wedge HTO on patellofemoral joint degeneration. If deformity correction exceeds an MPTA of 10° during open-wedge HTO, degeneration of patellofemoral joint needs to be considered.Level of evidence: Level IV.

Engineered nanoparticle exposure and cardiovascular effects: the role of a neuronal-regulated pathway

Human and animal studies have confirmed that inhalation of particles from ambient air or occupational settings not only causes pathophysiological changes in the respiratory system, but causes cardiovascular effects as well. At an equal mass lung burden, nanoparticles are more potent in causing systemic microvascular dysfunction than fine particles of similar composition. Thus, accumulated evidence from animal studies has led to heightened concerns about the potential short- and long-term deleterious effects of inhalation of engineered nanoparticles on the cardiovascular system. This review highlights the new observations from animal studies, which document the adverse effects of pulmonary exposure to engineered nanoparticles on the cardiovascular system and elucidate the potential mechanisms involved in regulation of cardiovascular function, in particular, how the neuronal system plays a role and reacts to pulmonary nanoparticle exposure based on both in vivo and in vitro studies. In addition, this review also discusses the possible influence of altered autonomic nervous activity on preexisting cardiovascular conditions. Whether engineered nanoparticle exposure serves as a risk factor in the development of cardiovascular diseases warrants further investigation.

Outcome of Low-Invasive Local Split-Thickness Lengthening for Iliotibial Band Friction Syndrome

Conventional surgical methods for iliotibial band friction syndrome (ITBFS) may affect the iliotibial band (ITB), delaying return to sports activities or impeding performance. We have developed a minimally invasive method. This study retrospectively analyzed the outcomes of this procedure in individuals with ITBFS. This study included 34 knees of 31 individuals. Surgery involved lengthening the central part of the ITB by splitting it into a superficial and a deep layer, maintaining the anterior and posterior fibers immediately above the lateral epicondyle. Outcomes included time to resume sports activity, personal best times to run a 5000-m race before and after surgery, and 2-month post-surgery muscle strengths. The mean postoperative time to return to competition was 5.8 weeks. Personal best times of 5000-m race improved in 13 of 17 runners. Two months post-surgery, the mean extensor muscle strengths on the healthy and affected sides did not significantly differ nor did the flexor muscle strengths. In ITBFS, the ITB itself is normal. Lengthening the limited region of the ITB immediately above the lateral femoral epicondyle removes the cause of ITBFS, with a reduction in inflammation. This technique resulted in early return to competition without degrading performance.

Incidental extra-cardiac findings on 13N-ammonia myocardial perfusion PET/CT

BACKGROUND

The objective of this study was to describe the prevalence of incidental extra-cardiac findings (IECFs) on myocardial perfusion PET/CTs and the prevalence of potentially clinically relevant and clinically irrelevant IECFs, as well as detection rate of previously unknown malignancies.

METHODS AND RESULTS

From September 2013 until February 2016, a total of 1397 consecutive patients referred for the evaluation of possible ischemia by 13NH3 PET/CT were prospectively included in a database. IECFs were categorized into three groups: potentially clinically relevant IECFs, IECFs that could potentially cause chest pain, and clinically irrelevant IECFs. Additionally, the prevalence of previously unknown malignancies was determined. In 717 (51%) of these patients, 775 IECFs were reported and 115 IECFs were categorized as potentially clinically relevant in 109 (8%) patients. A total of 145 IECFs that could potentially cause chest pain were detected in 139 (10%) patients and 515 clinically irrelevant IECFs were detected in 469 (34%) of the patients. An unknown primary malignancy was histologically proven in 19 patients (1.4%).

CONCLUSIONS

IECFs are detected on myocardial perfusion PET/CT in approximately half of the patients. In the present study, IECFs were potentially clinically relevant in 8% of the patients and in 1.4% an unknown malignancy was found, most of which were lung cancers.

Fixed-flexion view X-ray of the knee superior in detection and follow-up of knee osteoarthritis

A fixed flexion view (FFV) is useful for evaluating joint space when assessing the severity of osteoarthritis (OA) of the knee. We analyzed changes in joint space revealed by standing extended view (SEV) and FFV over a mean 4 years, to compare both views on their capacity to measure joint space width accurately at particular time points during follow-up.SEV and FFV images were acquired in patients with knee OA. The 81 patients (157 knees) followed up for ≥24 months were selected as study subjects. Medial joint space widths (MJSW), Kellgren-Lawrence (KL) grades, and reductions in MJSW on SEV (ΔSEV) and FFV (ΔFFV) were compared in knees evaluated by SEV and FFV.At both time-points, mean MJSW was significantly lower by FFV than by SEV. Mean MJSW was significantly lower at follow-up than at first examination by both SEV and FFV. At both time-points, the KL grade was higher by FFV than by SEV group. The ΔFFV was significantly greater than the ΔSEV. ΔSEV did not differ significantly among KL grades, but ΔFFV was significantly greater in patients with KL grade II than in patients with other KL grades.FFV is not only useful for evaluating joint space in knees with OA, but also for accurately evaluating the progression of OA. The risk of rapid progression of knee OA may be higher in patients with KL grade II, as determined by FFV. FFV may be superior to SEV in determining appropriate treatment strategies for knee OA.

Radiographic Measurement of Joint Space Width Using the Fixed Flexion View in 1,102 Knees of Japanese Patients with Osteoarthritis in Comparison with the Standing Extended View

Purpose

The fixed flexion view (FFV) of the knee is considered useful for evaluating the joint space when assessing the severity of osteoarthritis (OA) of the knee. To clarify the usefulness of FFV for evaluation of the joint space and severity of knee OA, this study evaluated changes in the joint space on the FFV and standing extended view (SEV) in patients with knee OA.

Materials and Methods

The SEV and FFV images were acquired in 567 patients (1,102 knees) who visited the hospital with a chief complaint of knee joint pain. Medial joint space width (MJSW) and Kellgren-Lawrence (K-L) classification assessed using the SEV and FFV images were compared.

Results

Mean MJSW was significantly smaller when assessed on the FFV than on the SEV (3.02±1.55 mm vs. 4.31±1.30 mm; p<0.001). The K-L grade was the same or higher on the FFV than on the SEV.

Conclusions

The FFV is more useful than the SEV for evaluating the joint space in OA knees. Treatment strategies in patients with knee OA should be determined based on routinely acquired FFV images.

Medial and Lateral Discoid Menisci of Both Knees

Discoid menisci on both the medial and lateral sides are rare, and there are very few reports on cases involving both sides. We report a case of a 52-year-old female with medial and lateral discoid menisci in both knees. Arthroscopy revealed the lateral menisci of both knees were complete discoid menisci, and partial meniscectomy was performed. The medial menisci were incomplete discoid menisci, but there were no findings of abnormal mobility or injury; therefore, the medial menisci were observed without treatment. At six months postoperatively, her pain and range of motion restrictions disappeared.

Comparative Effects of Periarticular Multimodal Drug Injection and Single-Shot Femoral Nerve Block on Pain Following Total Knee Arthroplasty and Factors Influencing Their Effectiveness

Purpose

This study compared the analgesic effects of local infiltration analgesia (LIA) and femoral nerve block (FNB) after total knee arthroplasty (TKA) and assessed factors associated with analgesia obtained by these two methods.

Materials and Methods

Study subjects included 66 patients (72 knees) who underwent TKA for osteoarthritis of the knee. Pain visual analogue scale (VAS), the amount of analgesics used, number of days to achieve 90° of flexion of the knee joint, date of initiating parallel-bar walking, range of motion of the knee joint at discharge, and adverse events were investigated.

Results

The VAS scores did not differ significantly between two groups, whereas the amount of analgesics used was significantly lower in the LIA group. Preoperative flexion contracture was significantly more severe in the LIA group with high VAS compared with low VAS. No serious adverse event occurred in the LIA or FNB group.

Conclusions

The lower analgesic usage in the LIA group than the FNB group indicates that the analgesic effect of LIA was greater than that of singleshot FNB after TKA. There were no serious complications in either group. The postoperative analgesic effect of LIA was smaller in patients with severe than less severe preoperative flexion contracture.

Fast Heating of Imploded Core with Counterbeam Configuration

A tailored-pulse-imploded core with a diameter of 70  μm is flashed by counterirradiating 110 fs, 7 TW laser pulses. Photon emission (>40  eV) from the core exceeds the emission from the imploded core by 6 times, even though the heating pulse energies are only one seventh of the implosion energy. The coupling efficiency from the heating laser to the core using counterirradiation is 14% from the enhancement of photon emission. Neutrons are also produced by counterpropagating fast deuterons accelerated by the photon pressure of the heating pulses. A collisional two-dimensional particle-in-cell simulation reveals that the collisionless two counterpropagating fast-electron currents induce mega-Gauss magnetic filaments in the center of the core due to the Weibel instability. The counterpropagating fast-electron currents are absolutely unstable and independent of the core density and resistivity. Fast electrons with energy below a few MeV are trapped by these filaments in the core region, inducing an additional coupling. This might lead to the observed bright photon emissions.

The influence of inhaled multi-walled carbon nanotubes on the autonomic nervous system

Background

Heart rate and cardiovascular function are regulated by the autonomic nervous system. Heart rate variability (HRV) as a marker reflects the activity of autonomic nervous system. The prognostic significance of HRV in cardiovascular disease has been reported in clinical and epidemiological studies. The present study focused on the influence of inhaled multi-walled carbon nanotubes (MWCNTs) on autonomic nervous system by HRV analysis.

Methods

Male Sprague–Dawley rats were pre-implanted with a telemetry device and kept in the individual cages for recovery. At week four after device implantation, rats were exposed to MWCNTs for 5 h at a concentration of 5 mg/m³. The real-time EKGs were recorded by a telemetry system at pre-exposure, during exposure, 1 day and 7 days post-exposure. HRV was measured by root mean square of successive differences (RMSSD); the standard deviation of inter-beat (RR) interval (SDNN); the percentage of successive RR interval differences greater than 5 ms (pNN5) and 10 ms (pNN10); low frequency (LF) and high frequency (HF).

Results

Exposure to MWCNTs increased the percentage of differences between adjacent R-R intervals over 10 ms (pNN10) (p < 0.01), RMSSD (p < 0.01), LF (p < 0.05) and HF (p < 0.01).

Conclusions

Inhalation of MWCNTs significantly alters the balance between sympathetic and parasympathetic nervous system. Whether such transient alterations in autonomic nervous performance would alter cardiovascular function and raise the risk of cardiovascular events in people with pre-existing cardiovascular conditions warrants further study.

Two patients treated with simeprevir plus pegylated-interferon and ribavirin triple therapy for recurrent hepatitis C after living donor liver transplantation: case report

We previously reported our data on telaprevir (TVR) used in combination with pegylated-interferon and ribavirin (PEG-IFN/RBV) for the treatment of recurrent hepatitis C virus (HCV) genotype 1 infection after liver transplantation (LT). TVR substantially increases the blood levels of immunosuppressive agents such as cyclosporine and tacrolimus for drug-drug interactions. On the other hand, the effect of simeprevir (SMV) on the blood levels of these immunosuppressive agents is unclear. We report 2 patients who achieved viral responses with little effect on the blood levels of cyclosporine and tacrolimus using SMV plus PEG-IFN/RBV treatment. The first was a 71-year-old woman with HCV-related liver cirrhosis and hepatocellular carcinoma who failed to respond to PEG-IFN/RBV after living donor LT. She was treated with 40 mg/d of cyclosporine, and received SMV plus PEG-IFN/RBV treatment. The second was a 65-year-old man with HCV-related liver cirrhosis who failed to respond to PEG-IFN/RBV after living donor LT. He was treated with 3 mg/d of tacrolimus, and received SMV plus PEG-IFN/RBV treatment. Serum HCV RNA became undetectable using TaqMan polymerase chain reaction (PCR) test after 4 weeks of treatment in both patients, and no remarkable fluctuation in blood concentration was observed either in cyclosporine or tacrolimus during the 12 weeks of SMV treatment. Completion of 12-week SMV triple therapy was followed by PEG-IFNα2b plus RBV, and both patients achieved sustained virological response 12 weeks after the end of treatment. SMV plus PEG-IFNRBV treatment showed a remarkable viral response with little effect on blood levels of immunosuppressive agents for recurrent HCV genotype 1 infection after LT.

Response to belimumab among patients with systemic lupus erythematosus in clinical practice settings: 24-month results from the OBSErve study in the USA

Objective

To examine disease activity and clinical outcomes, and describe overall patterns of systemic lupus erythematosus (SLE) care in patients who received belimumab in a real-world clinical setting.

Methods

This observational cohort study was conducted in US clinical practices. Rheumatologists (n=92) identified adults with SLE who had received ≥8 infusions of belimumab plus standard of care (SoC). Physicians assessed disease outcomes at 6-month intervals using patient medical charts, for up to 24 months. The primary outcome was physician-assessed change in SLE disease. Other outcomes included change in steroid use, laboratory tests and healthcare resource utilisation (HCRU).

Results

Of 501 patients (intent-to-treat population (ITT)), 446 were female, mean age was 43.3 years and 98% had moderate/severe disease activity at baseline (first dose of belimumab). Data for 277 patients who completed 24 months of belimumab treatment were available. Among the ITT, a ≥50% improvement in overall clinical response between baseline and month 6 was reported for 48.7% of patients; continued improvement was seen at all subsequent 6-month intervals relative to the previous timepoint. The percentage of patients with moderate/severe disease also decreased at each timepoint. At baseline, 77.0% of patients received steroids at a mean (SD) prednisone equivalent dose of 19.9 (14.39) mg/day, which decreased to 8.4 (7.35) mg/day at month 6 and 6.1 (9.31) mg/day at month 24. Abnormal laboratory values typically associated with SLE also demonstrated improvements at month 6, which continued through 24 months. HCRU decreased over the duration of the study.

Conclusions

Patients with SLE who received belimumab plus SoC for up to 24 months demonstrated improvements in disease severity and laboratory values and a reduction in steroid use and HCRU as early as month 6. Improvements continued through 24 months, providing evidence of reduced disease activity among patients taking belimumab in real-world clinical practice.