Background:
Time-dependent postoperative changes in knee joint line obliquity (KJLO) and subsequent adaptational changes in the hip and ankle joints have not been fully proven after medial open wedge ...high tibial osteotomy (MOWHTO).
Purpose:
To investigate the serial postoperative changes in KJLO and subsequent adaptational changes in the hip and ankle joints over time after MOWHTO.
Study design:
Case series, Level of evidence, 4.
Methods:
A total of 92 patients who underwent MOWHTO between April 2015 and December 2020 were evaluated. Radiographic parameters, including KJLO, ankle joint line obliquity (ALO), hip abduction angle (HAA), joint line convergence angle, weightbearing line ratio, and hip-knee-ankle angle, were analyzed in time sequence (preoperatively and 3, 6, 12, and 24 months postoperatively). Repeated-measures analysis of variance and post hoc analysis were used to demonstrate alterations and the statistical significance of KJLO and other related radiographic parameters over time.
Results:
The mean KJLO values were –1.9°, –2.1°, –2.7°, and –3.2° at 3, 6, 12, and 24 months postoperatively, respectively, indicating that there was consistent increase in valgus tilting of KJLO from 6 to 24 months (P < .001 for both 6-12 months and 12-24 months). ALO and HAA showed significant changes from 6 to 12 months (ALO, P < .001; HAA, P = .002), but not between 12 and 24 months (ALO: –3.0°, –2.7°, –1.9°, and −1.6°; HAA: –0.8°, –0.9°, –1.5°, and −1.8° at 3, 6, 12, and 24 months, respectively). The mean joint line convergence angle, weightbearing line ratio, and hip-knee-ankle angle did not change significantly from 3 months to 24 months postoperatively.
Conclusion:
There was a consistent increase in valgus tilting of the postoperative KJLO from 6 to 24 months after MOWHTO. The adaptive ALO and HAA significantly changed between 6 and 12 months and were maintained until 24 months after MOWHTO. It is necessary to consider the adaptive change when hip or ankle surgery is planned within this period.
This study investigated the rate of cartilage regeneration after an open-wedge high tibial osteotomy (HTO) without cartilage regeneration by second-look arthroscopy. This study included patients who ...underwent an open-wedge HTO between July 2014 and March 2019. A total of 65 patients were enrolled. Pre- and postoperative (second-look arthroscopy) hip-knee-ankle (HKA) angle and tibial slope were measured. All patients underwent arthroscopic examination prior to osteotomy. Medial femoral condyle (MFC) and medial tibial plateau (MTP) articular cartilage were evaluated according to the International Cartilage Repair Society (ICRS) grading system. After 26.5 months, second-look arthroscopy was performed with plate removal to identify the cartilage status of the MFC and MTP. The preoperative HKA angle (6.4° ± 2.7°) was well corrected postoperatively (-2.7° ± 2.7°,
< 0.001). In terms of MFC on second-look arthroscopy, 29 patients (44.6%) showed an improved ICRS grade, 31 patients (47.7%) were maintained, and 5 patients (7.7%) showed a worse ICRS grade since the prior operation. In the MTP group, 19 patients (29.2%) improved, 44 patients (67.7%) were maintained, and 2 patients (3.1%) worsened. Approximately 44.6% and 29.2% of patients showed improved cartilage statuses on the MFC and MTP after open-wedge HTO without any cartilage regeneration procedures. Cartilage regenerations in both the MFC and MTP did not influence clinical outcomes.
Background: Few studies have evaluated the impact of obesity on operation time in patients with ACL reconstruction. The purpose of this study was to understand the effect of obesity on operation time ...in patients with arthroscopic anterior cruciate ligament (ACL) reconstruction. Methods: A total of 103 patients were included. The mean pure operation time was 45.9 ± 13.4 min. Considering that 15 min incremental increases in operation time are an independent risk factor for complications, all patients were classified into two groups according to operation time: more or less than 61 min. Demographic data were compared between both groups. Pure operation time was defined as operative time without suture time (pure operation time = suture start time − operation start time). Correlation analysis between demographic data and pure operation time was performed, and multiple linear regression analysis was used to identify the predictors of pure operation time. Results: The pure operation time ≥61 min group (n = 34) had a 14.7 kg higher weight and 4.5 kg/m2 higher body mass index (BMI) than those with pure operation time < 61 min (n = 69). Weight (r = 0.635, p < 0.001) and BMI (r = 0.584, p < 0.001) were positively correlated with operation time. Multiple linear regression analysis showed that weight (β = 0.635, p < 0.001) was the only predictor of operation time. A weight of 74.25 kg was a cut-off value for a pure operation time of >61 min. Conclusions: The weight and BMI of the group with pure operation time of ≥61 min were 14.7 kg and 4.5 kg/m2 higher, respectively. The weight of patients with ACL tears was a factor affecting delay in the operation time. Patients weighing over 74.25 kg were more likely to delay ACL reconstruction.
Purpose
This study aimed to compare long‐term clinical and radiographic outcomes and survival rates between navigation‐assisted (NAV) total knee arthroplasty (TKA) and conventional (CON) TKA using a ...mobile‐bearing insert.
Methods
From May 2008 to December 2009, 45 and 63 mobile‐bearing TKA patients were enroled in the CON‐ and NAV‐TKA groups with 146.8 months follow‐up, respectively. Clinical outcomes (Western Ontario and McMaster University Osteoarthritis Index and Knee Society Scores), radiographic outcomes (hip‐knee‐ankle HKA, lateral distal femoral, medial proximal tibial, γ, and δ angles), and survivorship were compared between both groups.
Results
The number of HKA angle outliers (more than 3 degrees or less than −3 degree) was significantly lower in the NAV‐TKA group (24.4% vs. 9.5%, p = 0.036) than in the CON‐TKA group. However, long‐term clinical outcomes were similar between both groups. The cumulative survival rate (best‐case scenario) was 98.3% in the CON‐TKA group and 97.5% in the NAV‐TKA group, with no significant difference between the groups (p = 0.883).
Conclusion
Long‐term clinical outcomes and survival rates were similar between the two groups despite fewer outliers of postoperative lower‐limb alignment in the NAV‐TKA group. Excellent survival rates were observed in both groups using mobile‐bearing inserts.
Level of Evidence
Level IV, case series.
A CMOS (Complementary metal-oxide-semiconductor) Hall sensor with low power consumption and simple structure is introduced. The tiny magnetic signal from Hall device could be detected by a ...high-resolution delta-sigma ADC in presence of offset and flickering noise. Also, the offset as well as the flickering noise are effectively suppressed by the current spinning technique combined with double sampling switches of the ADC. The double sampling scheme of the ADC reduces the operating frequency and helps to reduce the power consumption. The prototype Hall sensor is fabricated in a 0.18-µm CMOS process, and the measurement shows detection range of ±150 mT and sensitivity of 110 µV/mT. The size of active area is 0.7 mm2, and the total power consumption is 4.9 mW. The proposed system is advantageous not only for low power consumption, but also for small sensor size due to its simplicity.
For patients who suffer from sensorineural hearing loss by damaged or loss of hair cells in the cochlea, biomimetic artificial cochleas to remedy the disadvantages of existing implant systems have ...been intensively studied. Here, a new concept of an inorganic‐based piezoelectric acoustic nanosensor (iPANS) for the purpose of a biomimetic artificial hair cell to mimic the functions of the original human hair cells is introduced. A trapezoidal silicone‐based membrane (SM) mimics the function of the natural basilar membrane for frequency selectivity, and a flexible iPANS is fabricated on the SM utilizing a laser lift‐off technology to overcome the brittle characteristics of inorganic piezoelectric materials. The vibration amplitude vs piezoelectric sensing signals are theoretically examined based on the experimental conditions by finite element analysis. The SM is successful at separating the audible frequency range of incoming sound, vibrating distinctively according to varying locations of different sound frequencies, thus allowing iPANS to convert tiny vibration displacement of ≈15 nm into an electrical sensing output of ≈55 μV, which is close to the simulation results presented. This conceptual iPANS of flexible inorganic piezoelectric materials sheds light on the new fields of nature‐inspired biomimetic systems using inherently high piezoelectric charge constants.
The new concept of a biomimetic artificial hair cell using a flexible inorganic piezoelectric acoustic nanosensor (iPANS) is presented. A highly sensitive flexible piezoelectric sensor that responds to sound‐driven vibrations of a thin silicone membrane is fabricated using a laser lift‐off process. The iPANS shows remarkable capability to sense tiny vibrations caused by an external sound wave.
Modern molecular docking comprises the prediction of pose and affinity. Prediction of docking poses is required for affinity prediction when three-dimensional coordinates of the ligand have not been ...provided. However, a large number of feature engineering is required for existing methods. In addition, there is a need for a robust model for the sequential combination of pose and affinity prediction due to the probabilistic deviation of the ligand position issue. We propose a pipeline using a bipartite graph neural network and transfer learning trained on a re-docking dataset. We evaluated our model on the released data from drug design data resource grand challenge 4 (D3R GC4). The two target protein data provided by the challenge have different patterns. The model outperformed the best participant by 9% on the BACE target protein from stage 2. Further, our model showed competitive performance on the CatS target protein.
A pipelined noise-shaping successive approximation register (NS-SAR) ADC with 1-2 multistage noise-shaping (MASH) structure is presented. Two-stage pipelined structure consisting of 5 bit NS-SAR and ...4 bit NS-SAR quantizers enables 3rd-order noise-shaping. A single operational transconductance amplifier (OTA) is shared by an integrator for noise-shaping and a residue amplifier for pipelining to maximize the power efficiency. The measured dynamic range (DR) is 84.6 dB when the sampling rate is 83.3 MS/s, bandwidth is 4 MHz, and power consumption is 3.5 mW showing Schreier figure-of-merit (FoM S,DR ) of 175.2 dB. The proposed ADC structure greatly relaxes design requirement of each SAR quantizer and can achieve high resolution and wide bandwidth with good power efficiency.
The videofluoroscopic dysphagia scale (VDS) was developed as an objective predictor of the prognosis of dysphagia after stroke. We evaluated the clinical validity of the VDS for various diseases. We ...reviewed the medical records of 1,995 dysphagic patients (1,222 men and 773 women) who underwent videofluoroscopic studies in Seoul National University Hospital from April 2002 through December 2009. Their American Speech–Language–Hearing Association’s National Outcome Measurement System (ASHA NOMS) swallowing scale, clinical dysphagia scale (CDS), and VDS scores were evaluated on the basis of the clinical and/or videofluoroscopic findings by the consensus of two physiatrists. The correlations between the VDS and the other scales were calculated. The VDS displayed significant correlations with the ASHA NOMS swallowing scale and the CDS in every disease group (
p
< 0.001 in all groups, including central and peripheral nervous system disorders), and these correlations were more apparent for spinal cord injury, peripheral nerve system disorders, and neurodegenerative diseases (correlation coefficients between the VDS and the ASHA NOMS swallowing scale: −0.603, −0.602, and −0.567, respectively). This study demonstrated that the VDS is applicable to dysphagic patients with numerous etiologies that cause dysphagia.
Appropriate customized auditory rehabilitation for hearing impaired subjects requires prediction of residual hearing and progression of hearing loss. Mutations in
TMPRSS3
encoding a transmembrane ...serine protease were reported to be associated with two different autosomal recessive nonsyndromic hearing loss (arNSHL) phenotypes, DFNB8 and DFNB10, in terms of residual hearing that may mandate different rehabilitation. We aimed to reveal the genetic contribution of
TMPRSS3
mutations among Korean populations and to correlate the clinical phenotype with
TMPRSS3
genotypes. Fifty families that segregated arNSHL and have visited our clinic recently for 2 years were recruited for
TMPRSS3 screening
. Novel
TMPRSS3
variants detected in our cohort were modeled using a predicted three-dimensional (3D) structure of the serine protease domain. The prevalence reached up to 11.2 % (3/27) among subjects with either prelingual hearing loss but retaining some degree of language development or with postlingual ski-slope hearing loss. We also found that a p.A306T allele is a founder allele in this population. Based upon the 3D modeling, we were able to correlate significant retention of residual low-frequency hearing and slower progression of its loss to this novel variant p.T248M that was predicted to have milder pathogenicity. A yeast-based protease assay confirmed a mild pathogenic potential of the p.T248M variant and a tight correlation between the protease activity and the residual hearing. Preservation of this low-frequency hearing should be of utmost importance when considering auditory rehabilitation. Our results significantly narrow down the candidate population for
TMPRSS3
sequencing for more efficient genetic diagnosis. More importantly, genotype–phenotype correlation of this gene observed in our cohort suggests that
TMPRSS3
can be an appropriate candidate for personalized and customized auditory rehabilitation.
Key message
The prevalence of
TMPRSS3
mutations among Korean postlingual hearing loss is 8.3 %.
The p.A306T variant of
TMPRSS3
is the common founder allele in Koreans.
A novel variant, p.T248M of
TMPRSS3
, was predicted to have milder pathogenicity.
There was a genotype–phenotype correlation of this gene in Koreans.
Our data support implication of this gene for personalized rehabilitation.
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