Postoperative assessment of the individualized humeral component retroversion in reverse total shoulder arthroplasty-a novel method applying CT scans without an elbow.

BACKGROUND: Humeral component retroversion (HcRV) can be customized to match native humeral retroversion (RV) during reverse total shoulder arthroplasty (RTSA). However, assessing postoperative individualized HcRV using computed tomography (CT) scans without an elbow can be challenging. Therefore, we developed a new method to obtain the HcRV and evaluated its reliability. METHODS: A total of 106 patients underwent RTSA using a single implant, in which the humeral component was implanted based on the preoperative humeral RV (Pre_HRV) using a bilateral CT scan of the elbow. Intraoperatively, a retroversion guide with version hole at 10° intervals was used; Pre_HRV was converted to 5° increments and applied for humeral component implantation. The axis of intertubercular sulcus (ITS) was defined as the line perpendicular to the intertubercular line, and the angle between the axis of ITS and the trans-epicondylar axis was defined as the bicipital groove rotation (BGR). ITS orientation was defined as the angle between the axis of ITS and the central axis of the humeral head. Since the BGR does not change, the postoperative implanted HcRV (Post_HcRV)f is calculated as the BGR minus the value of the postoperative ITS orientation. An agreement analysis was performed between Post_HcRV and both the intraoperatively applied humeral RV (I_HRV) and Pre_HRV, as well as between the pre- and postoperative ITS orientations. The humeral component's insertional errors were also evaluated. RESULTS: All radiologic measurements exhibited excellent inter- and intra-observer reliabilities. The reliabilities between Post_HcRV and both I_HRV and Pre_HRV, as well as between pre- and postoperative ITS orientations, showed excellent agreement (intraclass correlation coefficients: 0.953, 0.952, and 0.873, respectively). The humeral component was inserted within 5° in 86.8% of the planned humeral RV cases. CONCLUSIONS: The HcRV measured using the BGR and ITS orientations achieved good accuracy for restoring the planned humeral RV using a retroversion guide with the forearm axis. Therefore, this new radiological measurement method can aid orthopedic surgeons in confirming Post_HcRV on CT scans without an elbow.

Integration of Large-Area Halide Perovskite Single Crystals and Substrates via Chemical Welding Using an Ionic Liquid for Applications in X-ray Detection.

The large carrier lifetime mobility product and strong stopping power for high-energy X-rays make halide perovskites an attractive candidate for next-generation X-ray detectors. In particular, high-energy X-rays in the range of several tens of keV require halide perovskite absorber layers with thicknesses exceeding a few millimeters. To avoid carrier scattering caused by grain boundaries at such thicknesses, the utilization of single crystals is desirable. Large-area single crystals are predominantly grown in a freestanding form, and integration onto a substrate is necessary for the fabrication of commercial devices. However, an effective method for integrating large single crystals onto a substrate has not yet been developed. In this study, a large-area (20 cm2) MAPbBr3 single crystal is bonded to an indium tin oxide (ITO) substrate using an ionic liquid, showing strong adhesion strength of 164 kPa. X-ray detectors based on ITO/MAPbBr3 single crystal bonded by methylammonium acetate achieved excellent sensitivity of 91,200 µC Gyair-1 cm-2, the highest among substrate-integrated halide perovskite single crystal X-ray detectors.

Subacromial notching after reverse total shoulder arthroplasty.

BACKGROUND: Scapular notching is a well-known postoperative complication of reverse total shoulder arthroplasty (RTSA). However, subacromial notching (SaN), a subacromial erosion caused by repeated abduction impingement after RTSA, has not been previously reported in a clinical setting. Therefore, this study aimed to assess the risk factors and functional outcomes of SaN after RTSA. METHODS: We retrospectively reviewed the medical records of 125 patients who underwent RTSA with the same design between March 2014 and May 2017 and had at least 2 years of follow-up. SaN was defined as subacromial erosion observed at the final follow-up but not on the X-ray 3 months after surgery. Radiologic parameters representing the patient's native anatomy and degrees of lateralization and/or distalization during surgery were evaluated using preoperative and 3 months postoperative X-rays. The visual analogue scale of pain, active range of motion, and American Shoulder and Elbow Surgeons score were assessed preoperatively and at the final follow-up to evaluate the functional outcomes of SaN. RESULTS: SaN occurred in 12.8% (16/125) of enrolled patients during the study period. Preoperative center of rotation-acromion distance (P = .009) and postoperative humerus lateralization offset, which evaluated the degree of lateralization after RTSA (P = .003), were risk factors for SaN. The preoperative center of rotation-acromion distance and postoperative humerus lateralization cutoff values were 14.0 mm and 19.0 mm, respectively. The visual analogue scale of pain (P = .01) and American Shoulder and Elbow Surgeons score (P = .04) at the final follow-up were significantly worse in patients with SaN. CONCLUSIONS: SaN might adversely affect postoperative clinical outcomes. As SaN correlated with patients' anatomical characteristics and degree of lateralization during RTSA, the implant's degree of lateralization should be adjusted according to the patient's own anatomical characteristics.

Accuracy of electronic apex locators using heat-treated Ni-Ti file.

This study investigated the accuracy of two electronic apex locators (DentaPort and Bingo) using heat-treated nickel-titanium files. The true root canal length of 30 single-rooted teeth was determined using K files. Next, the electronically measured length was determined using two nickel-titanium files (ProGlider and HyFlex EDM Glide Path File) with two electronic apex locators at the 'APEX' marks. The accuracy of the electronic apex locator was evaluated by comparing the true root canal length and electronically measured length for each measurement. There was no significant difference between the measurements with two nickel-titanium files, and all differences between true root canal length and electronically measured length were within ±0.5 mm regardless of the type of nickel-titanium files or electronic apex locators. Based on the results, the heat treatment of the nickel-titanium files showed no adverse effects on the working length determination using electronic apex locators.

Revision Rotator Cuff Repair Versus Primary Repair for Large to Massive Tears Involving the Posterosuperior Cuff: Comparison of Clinical and Radiological Outcomes.

BACKGROUND: The retear rate after revision rotator cuff repair (rRCR) ranges from 50% to 90%. Patients who undergo primary RCR (pRCR) for large to massive rotator cuff tear (mRCT) also have unpredictable outcomes. PURPOSE: To compare the clinical outcomes after rRCR for a posterosuperior rotator cuff tear of any size with those after pRCR for mRCT and to identify the risk factors for poor outcomes and retear after rRCR. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Among patients with posterosuperior cuff tear treated between 2010 and 2017, the clinical outcomes of 46 patients who underwent rRCR were compared with 106 patients who underwent pRCR for mRCT. Between-group differences in patient-reported outcomes (visual analog scale [VAS] for pain, VAS for satisfaction and American Shoulder and Elbow Surgeons [ASES] and Constant scores) at final follow-up were evaluated and compared with previously published minimal clinically important difference (MCID) values. Radiological outcomes were evaluated using magnetic resonance imaging or ultrasonography at a minimum 1-year follow-up. Multivariate linear regression analysis was performed to identify the risk factors for poor ASES score, and multivariate logistic regression analysis was used to assess the risk factors for retear after rRCR. RESULTS: The mean follow-up was 26.4 months (range, 24-81 months). Although final VAS for pain, VAS for satisfaction, and ASES scores in the rRCR group were significantly worse than those in the pRCR group, the Constant score was similar between the groups. These differences in outcomes did not exceed the MCID threshold. The retear rate in the rRCR group was 50% compared with 39% for the pRCR group (P = .194). In the rRCR group, risk factors for worse ASES score were retear (P = .043; r = -11.3), lower body mass index (P = .032; r = 1.9), and lower preoperative VAS for pain (P = .038; r = 2.3), and risk factors for retear were preoperative high-grade fatty degeneration (Goutallier grades 3 and 4) of the supraspinatus muscle (P = .026; odds ratio, 5.2) and serum hyperlipidemia (P = .035; odds ratio, 11.8). CONCLUSION: Both study groups had similar clinical and radiological outcomes. Patients with symptomatic failed rotator cuff repairs having high-grade fatty degeneration of the supraspinatus muscle and/or serum hyperlipidemia had a greater likelihood of retear after rRCR.

Correction to: Relation of Superficial and Deep Layers of Delaminated Rotator Cuff Tear to Supraspinatus and Infraspinatus Insertions.

[This corrects the article DOI: 10.1007/s43465-019-00020-6.].

Significance of the acromiohumeral distance on stress radiography for predicting healing and function after arthroscopic repair of massive rotator cuff tears.

BACKGROUND: A decreased acromiohumeral distance (AHD) is commonly detected in patients with massive rotator cuff tears (mRCTs). Most studies evaluating fixed humeral elevation have used preoperative or postoperative standardized radiography and not stress radiography. This study aimed to evaluate the predictive role of the preoperative AHD measured using stress radiography (AHD_stress) in rotator cuff healing and function after arthroscopic repair of mRCTs. METHODS: The data of 113 patients who underwent arthroscopic repair of mRCTs were analyzed. Postoperative cuff integrity was evaluated using magnetic resonance imaging at 1 year, and shoulder function was evaluated at a mean of 34.9 ± 17.8 months (range, 24-92 months) postoperatively. Forty-seven patients showed healing failure. Propensity score matching (1-1) was performed between the healed group and healing failure group. Thirty-eight patients in each group were matched in the final analysis. The AHD and AHD_stress were defined as the shortest distances from the inferior acromion to the superior humerus on standard anteroposterior radiography and stress radiography (5.4-kg weight applied inferiorly in a neutral position), respectively. The AHD difference (AHD_diff) was defined as the difference between the AHD and AHD_stress values. Receiver operating characteristic curve analysis was performed to determine cutoff values for significant variables. RESULTS: No difference in the mean preoperative AHD was found between the healed group (7.5 ± 2.0 mm) and healing failure group (6.9 ± 2.2 mm, P = .234). The AHD_diff value was significantly higher in the healed group (4.4 ± 2.1 mm) than in the healing failure group (3.0 ± 2.0 mm, P = .002; cutoff, 3.2 mm). Patients with an AHD_diff value ≥ 3.2 mm showed a lower healing failure rate (28.9% vs. 71.1%, P < .001) and higher functional scores than patients with an AHD_diff value < 3.2 mm. The AHD_diff value was higher in patients with an American Shoulder and Elbow Surgeons (ASES) score ≥ 80 (4.9 ± 1.9 mm) than in those with an ASES score < 80 (3.1 ± 2.1 mm, P = .024). Among patients with healing failure, only the postoperative AHD showed a significant difference between those with an ASES score ≥ 80 (7.0 ± 2.5 mm) and those with an ASES score < 80 (4.8 ± 2.1 mm, P = .009; cutoff, 4.8 mm). CONCLUSION: A reducible AHD, which increased by ≥ 3.2 mm under stress radiography, can be a favorable predictor of rotator cuff healing and function after arthroscopic repair of mRCTs. Our findings suggest that this new and simple radiologic parameter should be considered preoperatively and would be helpful to determine appropriate treatment strategies.

Population analysis of the Korean native duck using whole-genome sequencing data.

BACKGROUND: Advances in next-generation sequencing technologies have provided an opportunity to perform population-level comparative genomic analysis to discover unique genomic characteristics of domesticated animals. Duck is one of the most popular domesticated waterfowls, which is economically important as a source of meat, eggs, and feathers. The objective of this study is to perform population and functional analyses of Korean native duck, which has a distinct meat flavor and texture phenotype, using whole-genome sequencing data. To study the distinct genomic features of Korean native duck, we conducted population-level genomic analysis of 20 Korean native ducks together with 15 other duck breeds. RESULTS: A total of 15.56 million single nucleotide polymorphisms were detected in Korean native duck. Based on the unique existence of non-synonymous single nucleotide polymorphisms in Korean native duck, a total of 103 genes related to the unique genomic characteristics of Korean native duck were identified in comparison with 15 other duck breeds, and their functions were investigated. The nucleotide diversity and population structures among the used duck breeds were then compared, and their phylogenetic relationship was analyzed. Finally, highly differentiated genomic regions among Korean native duck and other duck breeds were identified, and functions of genes in those regions were examined. CONCLUSIONS: This is the first study to compare the population of Korean native duck with those of other duck breeds by using whole-genome sequencing data. Our findings can be used to expand our knowledge of genomic characteristics of Korean native duck, and broaden our understanding of duck breeds.

Relation of Superficial and Deep Layers of Delaminated Rotator Cuff Tear to Supraspinatus and Infraspinatus Insertions.

BACKGROUND: It remains unclear whether the deep layer of the rotator cuff is an articular layer of the supraspinatus (SS) or infraspinatus (IS), rotator cable, or superior capsule. Therefore, this study aimed to analyse the relationship between occupation ratios and delamination patterns of rotator cuff tears (RCTs). We hypothesised that the deep layers are related to the occupation ratios of the deep SS and IS sections. MATERIALS AND METHODS: A total of 265 patients with RCTs were retrospectively enrolled between 2013 and 2017 and divided into four groups: A, non-delaminated tear; B, delaminated tear with the deep layer equally retracted to the superficial layer; C, delaminated tear with the deep layer more retracted; D, delaminated tear with the superficial layer more retracted. Muscle volume was evaluated by measurement of each occupation ratio of the SS and IS, and the IS muscle was additionally divided into two areas, deep and superficial. RESULTS: The SS occupation ratio was significantly lower in group C than in the other groups (p = 0.009). Conversely, comparison of the IS occupation ratios revealed no significant intergroup differences. The occupation ratio of the superficial IS was significantly lower in group D than in the other groups (p = 0.003). In group C, the occupation ratios of the deep IS section were significantly decreased according to RCT size (p = 0.034). CONCLUSION: Our findings demonstrate that the superficial layers are related to the IS superficial section and the deep layers to the SS and IS deep sections. LEVEL OF STUDY: IV.

Association of the thyroid hormone responsive spot 14 alpha gene with growth-related traits in Korean native chicken.

OBJECTIVE: Thyroid hormone responsive spot 14 alpha (THRSP) has been used to investigate the regulation of de novo lipogenesis because the variation of THRSP mRNA content in the tissue affects directly the ability of that tissue to synthetize lipids. Also, this gene responds to thyroid hormone stimulation and high level of carbohydrate feeding or insulin-injection. This study was carried out to investigate variations within THRSP and their effects on body and carcass weights in Korean native chicken (KNC). METHODS: A total of 585 chickens which represent the five lines of KNC (Black, Gray-Brown, Red-Brown, White, and Yellow-Brown) were reared and body weight data were recorded every two weeks from hatch until 20 weeks of age. Polymerase chain reaction- restriction fragment length polymorphism, DNA chips for Agilent 2100 Bioanalyzer, and Fluidigm Genotyping Technology, were applied to genotype selected markers. A linear mixed-effect model was used to access association between these single nucleotide polymorphism (SNP) markers and growth-related traits. RESULTS: A total of 30 polymorphisms were investigated in THRSP. Of these, nine SNPs for loci were selected to perform association analyses. Significant associations were detected between g.-49G>T SNP with body weight at 20 weeks of age (BW20), g.451T>C SNP with growth at 10 to 12 weeks of age (GR10-12), and g.1432A>C SNP with growth at 14 to 16 weeks trait (GR14-16) and body weight at 18 weeks of age (BW18). Moreover, diplotype of the THRSP gene significantly affected body weight at 12 weeks of age (BW12) and GR10-12 traits. Diplotype of ht1/ht2 was favorable for BW12 and GR10-12 traits. CONCLUSION: These results suggest that THRSP can be regarded as a candidate gene for growth traits in KNC.

Comparison of a novel hybrid hook locking plate fixation method with the conventional AO hook plate fixation method for Neer type V distal clavicle fractures.

BACKGROUND: The conventional AO hook locking compression plate (LCP) (Synthes, Solothurn, Switzerland) has only three holes for lateral fragments; therefore it is not suitable for use during the fixation of small-comminuted fragments in some cases. Recently, a novel hybrid hook LCP (TDM, Seoul, Korea) was developed to overcome this limitation. Here, we evaluated the clinical and radiologic outcomes of a novel hybrid hook LCP for Neer type V distal clavicle fractures compared to the outcomes of a conventional AO hook plate. METHODS: Seventy-eight consecutive patients who underwent hook LCP fixation for Neer type V distal clavicle fractures were included. The subjects were divided into 2 groups: the conventional AO hook LCP group and the novel hybrid hook LCP group. For clinical assessments, the American Shoulder and Elbow Surgeons (ASES) score, Korean shoulder score (KSS), and Constant score were recorded. The percentage modified coracoclavicular distance (MCCD %) was used for the evaluation of fracture reduction. Typical reported complications, such as secondary dislocation, implant failure or loosening, peri-implant fracture, acromion osteolysis, postoperative acromioclavicular joint arthrosis, non-union, or delayed union, were also analyzed. RESULTS: There were no differences in the clinical outcomes (ASES, KSS, and Constant scores) between the two groups. Bone union was achieved in a significantly shorter period in the hybrid hook LCP group (13.6±2.0weeks) than in the AO hook LCP group (17.5±4.8weeks, p<0.001). Consequently, the time to implant removal was also significantly shorter in the hybrid hook LCP group (4.0±0.5months) than in the AO hook LCP group (5.4±1.1months, p<0.001). The MCCD% showed no significant differences between the treatment groups. There was no statistically significant difference in the complication rate between the two groups; however, the hybrid hook LCP fixation resulted in a lower prevalence of hook-related complications. CONCLUSION: The hybrid hook LCP fixation showed satisfactory clinical and radiologic outcomes in comparison with the AO hook LCP fixation. The hybrid hook LCP is useful for multiple screw fixation of inferior comminuted fragments in Neer type V distal clavicle fractures. The bone union was significantly shorter; thus, the time to implant removal was also significantly shorter. LEVEL OF EVIDENCE: Level III, Retrospective study.

Comparative analysis of three different protocols for cholinergic neuron differentiation in vitro using mesenchymal stem cells from human dental pulp.

A decrease in the activity of choline acetyltransferase, the enzyme responsible for acetylcholine synthesis in the cholinergic neurons cause neurological disorders involving a decline in cognitive abilities, such as Alzheimer's disease. Mesenchymal stem cells (MSCs) can be used as an efficient therapeutic agents due to their neuronal differentiation potential. Different source derived MSCs may have different differentiation potential under different inductions. Various in vitro protocols have been developed to differentiate MSCs into specific neurons but the comparative effect of different protocols utilizing same source derived MSCs, is not known. To address this issue, dental pulp derived MSCs (DPSCs) were differentiated into cholinergic neurons using three different protocols. In protocol I, DPSCs were pre-induced with serum-free ADMEM containing 1 mM of ß-mercaptoethanol for 24 h and then incubated with 100 ng/ml nerve growth factor (NGF) for 6 days. Under protocol II, DPSCs were cultured in serum-free ADMEM containing 15 µg/ml of D609 (tricyclodecan-9-yl-xanthogenate) for 4 days. Under protocol III, the DPSCs were cultured in serum-free ADMEM containing 10 ng/ml of basic fibroblast growth factor (bFGF), 50 µM of forskolin, 250 ng/ml of sonic hedgehog (SHH), and 0.5 µM of retinoic acid (RA) for 7 days. The DPSCs were successfully trans-differentiated under all the protocols, exhibited neuron-like morphologies with upregulated cholinergic neuron-specific markers such as ChAT, HB9, ISL1, BETA-3, and MAP2 both at mRNA and protein levels in comparison to untreated cells. However, protocol III-induced cells showed the highest expression of the cholinergic markers and secreted the highest level of acetylcholine.

Critical shoulder angle and greater tuberosity angle according to the partial thickness rotator cuff tear patterns.

BACKGROUND: Current studies suggest that radiographic markers such as the critical shoulder angle (CSA) and the greater tuberosity angle (GTA) are associated with rotator cuff tears (RCTs). However, because the analysis of CSAs and GTAs according to the partial thickness rotator cuff tear patterns is limited, the purpose of the present study was to evaluate the relationship of CSAs and GTAs with partial thickness rotator cuff tear (PTRCT) patterns. METHOD: This retrospective study included 1,069 patients from 2013 to 2017. The subjects were divided into 4 groups: Group A, control group; Group B, articular-sided PTRCTs; Group C, bursal-sided PTRCTs; and Group D, full thickness rotator cuff tears (FTRCTs). RCTs were diagnosed with magnetic resonance imaging and the CSA and GTA were measured on simple radiographs. Multivariable analyses were used to clarify the potential risks for these pathologies. RESULTS: The mean CSAs of articular-sided PTRCTs (34.2°±4.7°) and FTRCTs (34.7°±4.4°) were significantly larger than those of the control group (32.3°±4.3°) and the bursal-sided PTRCTs (31.5°±4.6°), (P<0.001). Multivariable analysis also showed that larger CSAs had a significantly increased risk of both articular-sided PTRCTs and FTRCTs, with odds ratios of 1.12 and 1.17 per degree, respectively. The mean GTAs of bursal-sided PTRCTs (73.2°±4.8°) and FTRCTs (72.3°±5.4°) were significantly larger than that of the control group (70.5°±5.1°) (P<0.001), although the mean GTA of articular-sided PTRCTs (71.5°±6.9°) did not show a significant difference when compared with the other groups. Multivariable analysis also showed that larger GTAs had a significantly increased risk of both bursal-sided PTRCTs and FTRCTs, with odds ratios of 1.13 and 1.07 per degree, respectively. CONCLUSION: A large critical shoulder angle was associated more with articular-sided PTRCTs than bursal-sided PTRCTs. A large greater tuberosity angle was associated more with bursal-sided PTRCTs than with articular-sided PTRCTs. Both critical shoulder angle and greater tuberosity angle were positively associated with the occurrence of full thickness rotator cuff tears. LEVEL OF EVIDENCE: IV, Retrospective study.

Clinical outcomes of dual 3.5-mm locking compression plate fixation for humeral shaft fractures: Comparison with single 4.5-mm locking compression plate fixation.

BACKGROUND: Recently, several in vitro biomechanical studies that used dual small locking plate fixation for humeral shaft fractures have investigated. However, in vivo studies about dual plate fixation for humeral shaft fractures are limited. The purpose of our study was to report the outcomes of dual small plating for humeral shaft fractures in comparison with those of single large fragment plating. METHODS: Sixty consecutive patients who underwent an open reduction internal fixation for humeral shaft fractures at our institution from September 2014 to December 2017 were included. Single 4.5-mm locking compression plate (LCP) fixation was used in the first 40 cases, and dual 3.5-mm LCP fixation was used in the final 20 consecutive cases. Data were collected to define patient characteristics, injury mechanism, clinical outcomes, time to surgery, operative time, estimated blood loss, and complications. Using simple radiography during the follow-up period (6, 12, 24, and 52 weeks after surgery), the shoulder and elbow joint ranges of motion (ROM) were also evaluated. RESULTS: Demographic data, time to surgery, surgical time, and estimated blood loss had no significant differences between the two groups. No significant differences were observed in nonunion rate and union rate 3 months after surgery. However, two patients (5%) in the single 4.5-mm LCP fixation group showed metal failure and breakage. No significant differences were found in postoperative shoulder and elbow ROM. Three patients (7.5%) in the single plating group and one patient (5%) in the dual plating group developed radial nerve palsy after surgery. No vascular injury and deep infection were observed in either group. CONCLUSION: For diaphyseal humeral fractures, dual 3.5-mm LCP fixation to the humerus is a possible treatment choice. This method showed satisfactory union rate, ROM, and complication rate, without increasing surgical time, in comparison with the conventional single 4.5-mm LCP fixation. Level of evidence: III.

Greater tuberosity angle and critical shoulder angle according to the delamination patterns of rotator cuff tear.

The purpose was to evaluate the relationship between GTA, CSA, and the delamination patterns of RCTs. This study included 315 patients with RCTs from 2014 to 2018, retrospectively. The subjects were divided into 5 groups: Group A, control group; Group B, non-delaminated tear; Group C, delaminated tear with equally retraction of articular and bursal layer; Group D, articular layer more retracted delaminated tear, and Group E, bursal layer more retracted delaminated tear. In conclusion, large GTA and CSA were associated with rotator cuff tears. However, there was no difference of GTA and CSA according to the delamination patterns.

The supraspinatus occupation ratios of both the ≥ 50% articular- and bursal-side partial-thickness rotator cuff tears were low and the infraspinatus occupation ratio of the ≥ 50% bursal-side partial-thickness rotator cuff tears was low.

PURPOSE: The purpose of this study was to analyze the relationship between the occupation ratio and partial-thickness rotator cuff tears. METHODS: The study included and retrospectively investigated 683 patients with partial-thickness rotator cuff tears between 2013 and 2017. Fifty patients with impingement syndrome were also enrolled as the control group for normal-population comparison. The participants were divided into five groups: Group A, control group; Group B, < 50% articular-side tears; Group C, ≥ 50% articular-side tears; Group D, < 50% bursal-side tears; and Group E, ≥ 50% bursal-side tears. Muscle volume was evaluated by measurement of each occupation ratio of the supraspinatus and infraspinatus tendons on the most lateral view of the T1-weighted oblique-sagittal images in which the scapular spine remained in contact with the scapular body. RESULTS: Fifty patients were enrolled in Group A. A total of 683 patients with Partial thickness rotator cuff tear were divided and classified into the following groups: 272 into Group B, 153 into Group C, 161 into Group D, and 97 into Group E. The supraspinatus occupation ratios of all partial-thickness rotator cuff tear groups were significantly lower than those of the control group. Furthermore, the supraspinatus occupation ratios of Groups C and E (≥ 50% partial-thickness rotator cuff tears) were significantly lower than those of Groups B and D (< 50% partial-thickness rotator cuff tears). However, the infraspinatus occupation ratio of only Group E was significantly lower than that of the other groups. CONCLUSION: The supraspinatus occupation ratios of both the ≥ 50% articular- and bursal-side partial-thickness rotator cuff tears were lower than those of the other partial-thickness rotator cuff tears. Conversely, the infraspinatus occupation ratio of only the ≥ 50% bursal-side partial-thickness rotator cuff tears was low. LEVEL OF EVIDENCE: IV.

Identification of duck liver-expressed antimicrobial peptide 2 and characterization of its bactericidal activity.

OBJECTIVE: This study was conducted to identify duck liver-expressed antimicrobial peptide 2 (LEAP-2) and demonstrate its antimicrobial activity against various pathogens. METHODS: Tissue samples were collected from 6 to 8-week-old Pekin ducks (Anas platyrhynchos domesticus), total RNA was extracted, and cDNA was synthesized. To confirm the duck LEAP-2 transcript expression levels, quantitative real-time polymerase chain reaction was conducted. Two kinds of peptides (a linear peptide and a disulfide-type peptide) were synthesized to compare the antimicrobial activity. Then, antimicrobial activity assay and fluorescence microscopic analysis were conducted to demonstrate duck LEAP-2 bactericidal activity. RESULTS: The duck LEAP-2 peptide sequence showed high identity with those of other avian species (>85%), as well as more than 55% of identity with mammalian sequences. LEAP-2 mRNA was highly expressed in the liver with duodenum next, and then followed by lung, spleen, bursa and jejunum and was the lowest in the muscle. Both of LEAP-2 peptides efficiently killed bacteria, although the disulfide-type LEAP-2 showed more powerful bactericidal activity. Also, gram-positive bacteria was more susceptible to duck LEAP-2 than gram-negative bacteria. Using microscopy, we confirmed that LEAP-2 peptides could kill bacteria by disrupting the bacterial cell envelope. CONCLUSION: Duck LEAP-2 showed its antimicrobial activity against both gram-positive and gram-negative bacteria. Disulfide bonds were important for the powerful killing effect by disrupting the bacterial cell envelope. Therefore, duck LEAP-2 can be used for effective antibiotics alternatives.

Arthroscopic Acromioclavicular Fixation With Suture Tape Augmentation After Coracoclavicular Fixation With Dog Bone Button: Surgical Technique.

An arthroscopic technique for the surgical treatment of acute acromioclavicular (AC) joint injuries is presented in this study. This procedure aims to achieve both vertical and horizontal stability through the healing of both coracoclavicular (CC) and AC ligaments. As a routine maneuver, arthroscopic CC stabilization was applied using the dog bone button to obtain only vertical stability. Additional arthroscopic AC joint fixation with suture tape augmentation is simple and easy and provides a safe technique to achieve horizontal stability of the joint and to increase the vertical stability to minimize the complications of standard CC reconstruction techniques.

Microfracture in Linear, Isolated, Narrow, Engaging Hill-Sachs Lesion.

Treatment of Hill-Sachs lesions is still controversial despite the frequent incidence in patients with recurrent shoulder dislocation. We report the use of arthroscopic microfracture for the treatment of recurrent shoulder dislocation with a linear, isolated, narrow, engaging Hill-Sachs lesion. Arthroscopic microfracture can be an alternative treatment option to obtain healing of defects and avoid external rotation limitation in young, active patients with recurrent dislocation with linear, isolated, narrow, engaging lesions.

Effect of Surgical-Site, Multimodal Drug Injection on Pain and Stress Biomarkers in Patients Undergoing Plate Fixation for Clavicular Fractures.

BACKGROUND: Surgical-site, multimodal drug injection has recently evolved to be a safe and useful method for multimodal pain management even in patients with musculoskeletal trauma. METHODS: Fifty consecutive patients who underwent plating for mid-shaft and distal clavicular fractures were included in the study. To evaluate whether surgical-site injections (SIs) have pain management benefits, the patients were divided into two groups (SI and no-SI groups). The injection was administered between the deep and superficial tissues prior to wound closure. The mixture of anesthetics consisted of epinephrine hydrochloride (HCL), morphine sulfate, ropivacaine HCL, and normal saline. The visual analogue scale (VAS) pain scores were measured at 6-hour intervals until postoperative hour (POH) 72; stress biomarkers (dehydroepiandrosterone sulfate [DHEA-S], insulin, and fibrinogen) were measured preoperatively and at POH 24, 48, and 72. In patients who wanted further pain control or had a VAS pain score of 7 points until POH 72, 75 mg of intravenous tramadol was administered, and the intravenous tramadol requirements were also recorded. Other medications were not used for pain management. RESULTS: The SI group showed significantly lower VAS pain scores until POH 24, except for POH 18. Tramadol requirement was significantly lower in the SI group until POH 24, except for POH 12 and 18. The mean DHEA-S level significantly decreased in the no-SI group (74.2 ± 47.0 µg/dL) at POH 72 compared to that in the SI group (110.1 ± 87.1 µg/dL; p = 0.046). There was no significant difference in the insulin and fibrinogen levels between the groups. The correlation values between all the biomarkers and VAS pain scores were not significantly different between the two groups (p > 0.05). CONCLUSIONS: After internal fixation of the clavicular fracture, the surgical-site, multimodal drug injection effectively relieved pain on the day of the surgery without any complications. Therefore, we believe that SI is a safe and effective method for pain management after internal fixation of a clavicular fracture.