Outcomes of a Trans-Web Approach to Fractures around the Finger Metacarpophalangeal Joint.

Background: A fracture around the finger metacarpophalangeal joint (MCPJ) can be difficult to access. We developed a trans-web approach that could lead surgeons directly to this site. An incision across the web is believed to result in a web contracture. The aim of this study is to present the outcomes of the trans-web approach. Methods: This is a retrospective study of all patients in whom a trans-web approach was used to fix fractures around the MCPJ in the period from October 2008 and September 2020. The outcomes of the trans-web approach were evaluated by appearance of the scar, presence of pain in relation to the scar, grading web creep, range of motion at the MCPJ and degree of abduction and adduction of the finger. Any complications of surgery were also recorded. Results: This study included 10 patients with 11 fractures around the MCPJ (6 avulsion fractures and 5 extra-articular fractures). The mean follow-up was 5 months. Skin contractures did not occur in any avulsion fracture case where original or extended trans-web skin incisions were used. However, they occurred in 2 extra-articular cases treated via a trans-web plus a mid-lateral approach. The mean range of motion of the MCP joint in all the patients was 80° (range, 70°-95°). There was a 10° loss of abduction in one patient and temporary sensory disturbance in another patient. Both these patients had been treated with extended incisions. Conclusions: The trans-web incision is a useful approach for the open reduction of fractures around the finger MCPJ, especially in avulsion fractures of the lateral volar base of the proximal phalanx with minimal risk of scar contracture. The risk of scar contracture is higher when the trans-web incision is combined with a mid-lateral incision for extra-articular fractures. Levels of Evidence: Level IV (Therapeutic).

Improvement of Bone Marrow Necrosis by Tyrosine Kinase Inhibitor Substitution in a Pediatric Patient With Philadelphia Chromosome-positive Acute Lymphoblastic Leukemia.

Bone marrow necrosis (BMN) describes necrosis of the myeloid tissues without cortical bone involvement. Imatinib, a tyrosine kinase inhibitor, can trigger BMN during the treatment of malignant disease. In such cases, it is necessary to reduce imatinib dose or discontinue its administration, which could influence treatment outcomes. Here, we report a 6-year-old boy with Philadelphia chromosome-positive acute lymphoblastic leukemia, who developed BMN in response to imatinib. We replaced imatinib with dasatinib, and necrotic lesions gradually disappeared and were never exacerbated. In Philadelphia chromosome-positive acute lymphoblastic leukemia with BMN, tyrosine kinase inhibitor replacement may allow continued chemotherapy without intensity reduction.

Sensitive detection of GATA1 mutations using complementary DNA-based analysis for transient abnormal myelopoiesis associated with the Down syndrome.

INTRODUCTION: GATA1 mutation plays an important role in initiating transient abnormal myelopoiesis (TAM) and in the clonal evolution towards acute megakaryoblastic leukaemia (AMKL) associated with Down syndrome (DS). This study aimed to develop and validate the clinical utility of a complementary DNA (cDNA) analysis in parallel with the conventional genomic DNA (gDNA) Sanger sequencing (Ss), as an initial screening test for GATA1 mutations. METHODS: GATA1 mutations were evaluated using both gDNA and cDNA in 14 DS patients using Ss and fragment analysis (FA), respectively. RESULTS: The detection sensitivity of conventional gDNA sequencing was limited in low blast percentage TAM (LBP-TAM); however, cDNA-based Ss readily detected all the pathognomonic GATA1 mutations. The cDNA-based FA readily detected GATA1 frameshift mutation with a reliable sensitivity ranging from 0.005% to 0.01% of clonal cells. CONCLUSIONS: GATA1 mutations are heterogeneous; therefore, we would like to propose a dual cDNA and gDNA analysis as a standard diagnostic approach, especially for LBP-TAM. cDNA-based FA promises an excellent sensitivity for detecting frameshift GATA1 mutations in the longitudinal clonal evolution towards AMKL without using a patient specific primer.

Wiener-Hammerstein model and its learning for nonlinear digital pre-distortion of optical transmitters.

We present a simple nonlinear digital pre-distortion (DPD) of optical transmitter components, which consists of concatenated blocks of a finite impulse response (FIR) filter, a memoryless nonlinear function and another FIR filter. The model is a Wiener-Hammerstein (WH) model and has essentially the same structure as neural networks or multilayer perceptrons. This awareness enables one to achieve complexity-efficient DPD owing to the model-aware structure and exploit the well-developed optimization scheme in the machine learning field. The effectiveness of the method is assessed by electrical and optical back-to-back (B2B) experiments, and the results show that the WH DPD offers a 0.52-dB gain in signal-to-noise ratio (SNR) and 6.0-dB gain in optical modulator output power at a fixed SNR over linear-only DPD.

Changes in the Rate of Postoperative Flexor Tendon Rupture in Patients with Distal Radius Fractures.

Background: Flexor tendon rupture is a major complication after volar locking plating for distal radius fracture (DRF). Few studies have investigated changes in the rate of postoperative flexor tendon rupture in patients with DRFs. The present study aimed to investigate the changes in the rate of postoperative flexor tendon rupture and to assess plate placement and reduction positions. Methods: We retrospectively reviewed patients in whom more than 24 months had passed since DRF surgery. The patients were interviewed by telephone. Forty-nine patients (50 fractures; 2007-2009) from institution A were included in group 1 and 81 patients (84 fractures; 2013-2016) from institution B were included in group 2. The DRF surgery method was similar between the two groups. The rate of flexor tendon rupture, Soong classification grade, and radiological index (i.e., volar tilt [VT], radial inclination [RI], and ulnar variance [UV]) were statistically investigated in both groups. Results: Patient epidemiology was not significantly different between the two groups. The flexor tendon rupture rates were 2% and 0% in groups 1 and 2, respectively, without a significant difference. With regard to the Soong grade, 44 fractures were grade 2 and 6 were grade 1 in group 1, whereas 18 were grade 2, 38 were grade 1, and 28 were grade 0 in group 2, with a significant difference (p < 0.05). With regard to the radiological index, the mean VT values were 5° and 11° in groups 1 and 2, respectively, with a significant difference (p < 0.05). However, RI and UV showed no significant difference. Conclusions: Plate placement and reduction positions, which are risk factors for flexor tendon ruptures after DRFs, have improved recently when compared with previous findings. With these changes, the rate of flexor tendon rupture is presumed to have decreased.

Clinical Outcomes of Ready-Made J-Shaped Nail Fixation for Unstable Metacarpal Fractures.

Background: The purpose of this study was to report the clinical outcomes of ready-made J-shaped intramedullary nail fixation for unstable metacarpal fractures. Methods: A total of 25 unstable fractures from 24 patients were evaluated in this retrospective study, comprising 20 metacarpal neck and 5 metacarpal shaft fractures. The mean follow-up was 22 weeks. Functional outcomes were assessed based on the range of motion of the metacarpophalangeal joint. Radiographic outcomes were evaluated by four projections of the postoperative plain radiographs at the final follow-up, and then were rated as excellent if projections at the fracture site showed no correction loss or angular deformity greater than 10°. Surgery time and complications during the treatments were recorded for each case. Results: All 25 fractures obtained bony union. The mean range of motion of the metacarpophalangeal joint was 78° (range, 45°-90°). Radiographic outcomes were excellent in 24 (96%) of 25 fractures. Only one fracture had correction loss. The mean surgery time was 29 minutes (range, 14-61 minutes). Two cases had extensor tendon adhesion at the insertion site, which was easily released when the implant was removed. Conclusions: This study demonstrates that intramedullary fixation with a ready-made J-shaped nail is a reliable treatment option for unstable metacarpal fractures.

Ratio of dislocation types of the proximal interphalangeal joint of the fingers: A new classification system for initial therapy.

BACKGROUND: We proposed a new system named the sagittal, coronal, axial, rotational and fracture (SCARF) classification, which can simply explain any condition of proximal interphalangeal (PIP) joint dislocations of the fingers. The purpose of this study was to verify that this classification would contribute to management of PIP joint dislocations at the initial therapy. We determined ratios of five factors in PIP dislocations with SCARF by interpreting radiographs and assessed the interobserver and intraobserver variability. METHODS: In total, 68 fingers in 67 consecutive patients were studied. The SCARF classification is composed of five factors: (1) sagittal plane displacement is rated by dorsal (D), volar (V), or neutral (N); (2) coronal plane displacement, by ulnar (U), radial (R), or neutral (N); (3) axial force, by compression (C), traction (T), or no (N); (4) rotational displacement, by supine (S), prone (P), or neutral (N); and (5) fracture concomitance, by minus (-) or plus (+). The row of the five characters explains each condition of PIP joint dislocations. Interobserver and intraobserver variability was determined after six orthopedic surgeons independently classified the same radiographs twice. RESULTS: All 68 dislocations were classified into 14 types, unless fracture concomitance was considered. The most common type was DUNN (35%). In coronal plane displacements, the two ulnar fingers showed a higher tendency to the ulnar position. Ring finger fracture concomitance was higher than in middle fingers or little fingers. In interobserver analysis, mean kappa coefficient for each factor was 0.63, 0.75, 0.68, 0.33, and 0.84, respectively. In intraobserver analysis, that was 0.73, 0.79, 0.71, 0.41, and 0.81, respectively. CONCLUSIONS: Even other than hand specialists can specify the type of every PIP dislocation by using the SCARF classification and will have better understanding of the disorder. It would contribute to management of PIP dislocations at the initial therapy. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.

Single-channel 200 Gbit/s, 10 Gsymbol/s-1024 QAM injection-locked coherent transmission over 160 km with a pilot-assisted adaptive equalizer.

We demonstrate a 10 Gsymbol/s, 1024 quadrature amplitude modulation (QAM) 160 km coherent transmission with an injection locking technique. Our newly developed, pilot-assisted adaptive equalizer has greatly improved the precision of waveform distortion compensation, and this has enabled us to increase the symbol rate to 10 Gsymbol/s in a 1024 QAM transmission. Thus, we could realize a 200 Gbit/s, 1024 QAM transmission over 160 km with a potential spectral efficiency of 12.6 bit/s/Hz.

Observation of guided acoustic-wave Brillouin scattering noise and its compensation in digital coherent optical fiber transmission.

We describe the first observation of guided acoustic-wave Brillouin scattering (GAWBS) phase noise in a digital coherent optical fiber transmission. GAWBS noise, which is a forward lightwave generated by thermally excited vibration modes in a cylindrical fiber structure, occurs coherently not only in a signal at a single carrier frequency, but also in modulated wide-band optical signals. Since the signal-to-GAWBS-noise ratio is independent of signal power, it has caused problems in various fields including quantum optics. We point out that GAWBS noise exists even in a digital coherent transmission system such as quadrature amplitude modulation (QAM) and degrades the transmission performance since the phase noise is inevitably included within the bandwidth of the transmitted data. We propose two analogue and one digital method to compensate for the GAWBS noise and demonstrate improved performance in a QAM digital coherent transmission.

Experimental and numerical comparison of probabilistically shaped 4096 QAM and a uniformly shaped 1024 QAM in all-Raman amplified 160 km transmission.

We describe an experimental and numerical comparison of a probabilistically shaped (PS) 4096 QAM signal and a uniformly shaped 1024 QAM signal. Both modulation formats have the same transmission rate and a spectral efficiency of 15.3 bit/s/Hz. In the computational simulation, we compared the generalized mutual information (GMI) of both modulation formats with bit-wise soft decision decoding and bit-wise hard decision decoding. For bit-wise hard decision decoding with an overhead of 7%, a shaping gain of 1.8 dB was attained. Then we successfully transmitted a single-channel PS-4096 QAM signal for the first time in an all-Raman amplified 160-km link, in which the transmission performance was improved compared with a uniformly shaped 1024 QAM with the same transmission rate. Transmissions with a high QAM multiplicity were achieved by using an optical phase-locked loop (OPLL) and a frequency stabilized fiber laser locked to an acetylene absorption line. Thanks to a shaping gain based on a bit-wise hard decision decoder, the 1.9-dB power margin, which agreed with the simulation result to within 0.1 dB, was increased after transmission.

Field trial of distance-adaptive optical transmission with digital in-band OSNR estimation.

We present a feasible distance-adaptive optical transmission system that selects the optimum modulation format by referencing the estimated optical signal to noise ratio (OSNR) information transmitted from an opposing transceiver via a feedback channel. A modulation format free time-domain-multiplexed pilot sequence enables OSNR estimation and feedback channel transmission. Thanks to a feedback channel transmission, this system does not need to pass through a control plane in optimizing scheme. Using this system, we demonstrated 106.6 Gb/s QPSK and 213.3 Gb/s 16 QAM distance-adaptive optical transmission in a fully automatic manner in a field-installed fiber of 70.4 to 211.2 km.

Closed mallet thumb injury: Our experience of 10 patients treated with surgery and a systematic review.

OBJECTIVE: This retrospective study reports 10 patients with closed mallet thumb injury treated with surgery and compares the clinical outcomes achieved with those of previously described patients who were treated with either conservative therapy or surgery. METHODS: We report the outcomes of a series of 10 patients who received surgical treatment at our institutions. Due to the rarity of closed mallet thumb, a systematic review was conducted, and the results of a literature search were compared with our case series to strengthen our conclusions. The previously described patients were categorized into two groups: the surgically treated group (16 patients) and the conservatively treated group (10 patients). The following patient and injury characteristics were documented: age, gender, injured side, time from injury to treatment, mechanism of injury, extension lag at first visit, postoperative range of motion (ROM) of the interphalangeal joint, immobilization period, and follow-up period. RESULTS: Statistical analyses showed no significant differences in the clinical results, except for shorter immobilization periods between our series and the previously described patients involving conservative treatment (4.9 ± 0.9 vs. 9.5 ± 2.3 weeks, respectively; P = 0.0053). CONCLUSIONS: This study suggests that surgery may result in more rapid recovery.

Quantitative assessment of rotator cuff muscle elasticity: Reliability and feasibility of shear wave elastography.

Ultrasound imaging has been used to evaluate various shoulder pathologies, whereas, quantification of the rotator cuff muscle stiffness using shear wave elastography (SWE) has not been verified. The purpose of this study was to investigate the reliability and feasibility of SWE measurements for the quantification of supraspinatus (SSP) muscle elasticity. Thirty cadaveric shoulders (18 intact and 12 with torn rotator cuff) were used. Intra- and inter-observer reliability was evaluated on an established SWE technique for measuring the SSP muscle elasticity. To assess the effect of overlying soft tissues above the SSP muscle, SWE values were measured with the transducer placed on the skin, on the subcutaneous fat after removing the skin, on the trapezius muscle after removing the subcutaneous fat, and directly on the SSP muscle. In addition, SWE measurements on 4 shoulder positions (0°, 30°, 60°, and 90° abduction) were compared in those with/without rotator cuff tears. Intra- and inter-observer reliability of SWE measurements were excellent for all regions in SSP muscle. Also, removing the overlying soft tissue showed no significant difference on SWE values measured in the SSP muscle. The SSP muscle with 0° abduction showed large SWE values, whereas, shoulders with large-massive tear showed smaller variation throughout the adduction-abduction positions. SWE is a reliable and feasible tool for quantitatively assessing the SSP muscle elasticity. This study also presented SWE measurements on the SSP muscle under various shoulder abduction positions which might help characterize patterns in accordance to the size of rotator cuff tears.

Dynamic changes in the accumulation of metabolites in brackish water clam Corbicula japonica associated with alternation of salinity.

The brackish water clam Corbicula japonica inhabits rivers and brackish waters throughout Japan where the major fishing grounds in the Ibaraki Prefecture, Japan, are located at the Hinuma Lake and Hinuma River. Water salinity in the Lake Hinuma is low and stable due to the long distance from the Pacific Ocean, whereas that in the downstream of the river varies daily due to a strong effect of tidal waters. In the present study, we dissected the gill and foot muscle of brackish water clam collected from these areas, and subjected them to metabolome analysis by capillary electrophoresis-time-of-flight mass spectrometry. More than 200 metabolites including free amino acids, peptides and organic acids were identified, and their amounts from the foot muscle tend to be higher than those from the gill. The principal component analysis revealed that the amount of each metabolite was different among sampling areas and between the gill and foot muscle, whereas no apparent differences were observed between male and female specimens. When the metabolites in the female clam at high salinity were compared with those at low salinity, concentrations of ß-alanine, choline, γ-aminobutyric acid, ornithine and glycine betaine were found to be changed in association with salinity. We also compared various metabolites in relation to metabolic pathways, suggesting that many enzymes were involved in their changes depending on salinity.

A photofuel cell comprising titanium oxide and silver(I/0) photocatalysts for use of acidic water as a fuel.

A photofuel cell comprising two photocatalysts TiO2 and Ag-TiO2 is demonstrated. The open circuit voltage, short circuit current, and maximum electric power of the PFC were 1.59 V, 74 µA, and 14 µW, respectively. The electron flow was rectified due to the Schottky barrier between TiO2 and Ag nanoparticles.

The effect of Anti-NGF receptor (p75 Neurotrophin Receptor) antibodies on nociceptive behavior and activation of spinal microglia in the rat brachial plexus avulsion model.

STUDY DESIGN: We measured the response of the behavior and spinal glial activation to anti-nerve growth factor receptor (p75 neurotrophin receptor [p75NTR]) antibodies in the rat brachial plexus avulsion (BPA) model. OBJECTIVE: The aim of this study was to investigate the effect of anti-p75NTR antibodies on nociceptive behavior and activation of spinal microglia in the rat BPA model. SUMMARY OF BACKGROUND DATA: Tanezumab (anti-nerve growth factor antibody) treatment is associated with pain reduction and improvement in function, but with several complications. METHODS: Thirty male Wistar rats were used. In the BPA group, the C8-T1 roots were avulsed from the spinal cord with forceps at the lower trunk level and 10 µL of saline was applied locally (n = 10). In the anti-p75NTR group, the C8-T1 roots were avulsed and 10 µL of anti-p75NTR antibody was applied locally (n = 10). In a sham-operated group, the lower trunk was simply exposed (n = 10). Mechanical hyperalgesia and pain-induced walking patterns were measured using von Frey filaments (Stoelting, Wood Dale, IL) and the CatWalk gait analysis (Noldus Information Technology, the Netherlands) system every third day for 3 weeks. Activation of astrocytes and microglia was immunohistochemically examined in the spinal cord using anti-glial fibrillary acidic protein (GFAP) and anti-Iba1 antibodies both 7 and 21 days after surgery. RESULTS: Animals in the BPA group displayed significant mechanical hyperalgesia that continued through day 21 compared with animals in the sham-operated group, and mechanical hyperalgesia in the anti-p75NTR group was significantly improved 6 days after the operation. Regarding pain-induced gait analysis via CatWalk, animals in the BPA group displayed a significantly greater pain-like gait pattern than the p75 group for up to 3 weeks. Levels of GFAP-immunoreactive astrocytes and Iba1-immunoreactive microglia in the anti-p75NTR group were significantly reduced compared with the BPA group. CONCLUSION: Our results suggest that p75NTR contributes to neuropathic pain associated with BPA, and that inhibition of p75NTR reduces neuropathic pain. LEVEL OF EVIDENCE: N/A.