Evaluating Scapular Notching after Reverse Total Shoulder Arthroplasty

Young-Kyu Kim,Jun-Sung Won,Chang-Kyu Park,Jong-Geun Kim 대한견주관절의학회 2015 대한견주관절학회지 Vol.18 No.4

Background: Scapular notching can happen at diverse location depending on implant design or operative technique, therefore, it is easily misdiagnosed. Thus, this study purposed to suggest a method helpful to assess scapular notching. Methods: The subjects were 73 cases of reverse shoulder arthroplasty (RSA) for cuff tear arthropathy during the period from May 2009 to April 2014 and followed-up for over a year. There was medialized RSA in 22 cases, bone increased offset RSA (BIO-RSA) in 36 cases, and metal increased offset RSA (metal-RSA) in 15 cases. Scapular notching was not determined by bone defect at the inferior of glenosphere as Sirveaux’s classification, but scapular notching at the site where the rotational route of the polyethylene of humeral implant met the scapular neck were examined. The results were compared with conventional method. Results: By conventional method, scapular notching was observed in 10 cases (45.5%) in medialized RSA, 12 cases (33.3%) in BIO-RSA, and none in metal-RSA. By new method, it was observed in 9 cases (40.9%) in medialized RSA, 10 cases (27.8%) in BIO-RSA, and none of metal-RSA. The site of scapular notching was apart from glenoshpere in 18 cases, and at inferior of glenosphere in 1 case. Absorption of bone graft was observed in 4 (11.1%) out of 36 cases of BIO-RSA. Conclusions: It is hard to distinguish scapular notching from absorption of bone graft in BIO-RSA, and bone absorption at the lateral lower end of glenoid in medialized RSA. Thus, it is considered useful to assess scapular notching at the site where the rotational route of the polyethylene insert meets scapular neck.

Risk of Anterior Femoral Notching in Navigated Total Knee Arthroplasty

이주홍,왕성일 대한정형외과학회 2015 Clinics in Orthopedic Surgery Vol.7 No.2

We retrospectively investigated the prevalence of femoral anterior notching and risk factors after total knee arthroplasty (TKA) using an image-free navigation system. Methods: We retrospectively reviewed 148 consecutive TKAs in 130 patients beginning in July 2005. Seventy knees (62 patients) underwent conventional TKA, and 78 knees (68 patients) received navigated TKA. We investigated the prevalence of femoral anterior notching and measured notching depth by conventional and navigated TKA. Additionally, the navigated TKA group was categorized into two subgroups according to whether anterior femoral notching had occurred. The degree of preoperative varus deformity, femoral bowing, and mediolateral suitability of the size of the femoral component were determined by reviewing preoperative and postoperative radiographs. The resection angle on the sagittal plane and the angle of external rotation that was set by the navigation system were checked when resecting the distal femur. Clinical outcomes were compared using range of motion (ROM) and the Hospital for Special Surgery (HSS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAX) scores between the two groups. Results: The prevalence of anterior femoral notching by conventional TKA was 5.7%, and that for navigated TKA was 16.7% (p = 0.037). Mean notching depth by conventional TKA was 2.92 ± 1.18 mm (range, 1.8 to 4.5 mm) and 3.32 ± 1.54 mm (range, 1.55 to 6.93 mm) by navigated TKA. Preoperative anterior femoral bowing was observed in 61.5% (p = 0.047) and both anterior and lateral femoral bowing in five cases in notching group during navigated TKA (p = 0.021). Oversized femoral components were inserted in 53.8% of cases (p = 0.035). No differences in clinical outcomes for ROM or the HSS and WOMAX scores were observed between the groups. A periprosthetic fracture, which was considered a notching-related side effect, occurred in one case each in the conventional and navigated TKA groups. Conclusions: Surgeons should be aware of the risks associated with anterior femoral notching when using a navigation system for TKA. A modification of the femoral cut should be considered when remarkable femoral bowing is observed.

Mid-term outcomes of bony increased offset-reverse total shoulder arthroplasty in the Asian population

Kirtan Tankshali,Dong-Whan Suh,Jong-Hun Ji,Chang-Yeon Kim 대한견주관절의학회 2021 대한견주관절의학회지 Vol.24 No.3

Background: To evaluate clinical and radiological outcomes of bony increased offset-reverse total shoulder arthroplasty (BIO-RSA) in the Asian population at mid-term follow-up. Methods: From June 2012 to August 2017 at a single center, 43 patients underwent BIO-RSA, and 38 patients with minimum 2 years follow-up were enrolled. We evaluated the clinical and radiological outcomes, and complications at the last follow-up. In addition, we divided these patients into notching and no-notching groups and compared the demographics, preoperative, and postoperative characteristics of patients. Results: Visual analogue scale, American Shoulder and Elbow Surgeons, University of California-Los Angeles Shoulder Scale, and Simple Shoulder Test scores improved significantly from preoperative (5.00, 3.93, 1.72, 3.94) to postoperative (1.72, 78.91, 28.34, 7.66) (p<0.05) outcomes. All range of motion except internal rotation improved significantly at the final follow-up (p<0.05), and the bone graft was well-incorporated with the native glenoid in all patients (100%). However, scapular notching was observed in 20 of 38 patients (53%). In the comparison between notching and no-notching groups (18 vs. 20 patients), there were no significant differences in demographics, radiological parameters, and clinical outcomes except acromion-greater tuberosity (AT) distance (p=0.003). Intraoperative complications included three metaphyseal fractures and one inferior screw malposition. Postoperative complications included ectopic ossification, scapular neck stress fracture, humeral stem relaxation, and late infection in one case each. Conclusions: BIO-RSA showed improved clinical outcomes at mid-term follow-up in Asian population. However, we observed higher scapular notching compared to the previous studies. In addition, adequate glenoid lateralization with appropriate humeral lengthening (AT distance) might reduce scapular notching.

Long-term Reverse Total Shoulder Arthroplasty Outcomes: The Effect of the Inferior Shifting of Glenoid Component Fixation

Philippe Collotte,Michael Bercik,Thais Dutra Vieira,Gilles Walch 대한정형외과학회 2021 Clinics in Orthopedic Surgery Vol.13 No.4

Background: The 155° Grammont reverse shoulder replacement has a long track record of success, but also a high radiographic notching rate. The increased distance between the scapular pillar and the humeral component theoretically decreases postoperative notching. The glenoid component can be shifted inferiorly relative to the glenoid; however, there also is some concern that shifting the glenoid component too far inferiorly (inferior glenoid component overhang > 3.5 mm) may compromise long-term stability of the glenoid component. This study was conducted to determine if clinical outcomes, scapular notching, and complications vary with more inferior placement of the glenoid component. Methods: A retrospective analysis of prospectively collected data was performed in order to compare radiographic outcomes (notching rate and signs of glenoid loosening or component disassembly) and clinical outcomes (range of motion, Constant score, subjective shoulder value, and complication rate) of all patients who underwent reverse shoulder replacement with the glenosphere positioned either flush with the inferior rim of the glenoid (flush group) or with at least 3.5 mm of inferior overhang (overhang group) at a minimum follow-up of 60 months. Ninety-seven patients ultimately met the inclusion criteria, with 41 patients with flush glenoid component and 56 patients with at least 3.5 mm of inferior overhang. Results: Average follow-up was 97.8 months. The overhang group had a lower rate of radiographic notching (37% vs. 82.5%, p < 0.05), better clinical outcomes (improvement in Constant score: +40 vs. +32, p = 0.036), and higher subjective shoulder value (79 vs. 69, p = 0.026) than the flush group. No difference in complications between groups was found. Conclusions: In this study, at least 3.5 mm of inferior glenosphere overhang relative to the inferior rim of the glenoid was associated with the lower notching rate without negative effect on the clinical outcomes in 155° Grammont-style reverse shoulder replacement. Therefore, no increase in complications should be expected when using this surgical technique.

SiOG 공정을 이용한 고 신뢰성 MEMS 자이로스코프

이문철,강석진,정규동,좌성훈,조용철,Lee Moon Chul,Kang Seok Jin,Jung Kyu Dong,Choa Sung-Hoon,Cho Yang Chul 한국마이크로전자및패키징학회 2005 마이크로전자 및 패키징학회지 Vol.12 No.3

MEMS에서 제조 공정 오차 및 외부 응력은 진동형 자이로스코프와 같은 MEMS 소자의 제조 수율에 많은 영향을 미친다. 특히 비연성 진동형 자이로스코프의 경우 감지모드와 구동모드의 주파수 차의 특성은 수율에 직접적인 영향을 미친다. SOI (Silicon-On-Insulator) 공정 및 양극접합 공정으로 패키징된 자이로스코프의 경우, 노칭현상으로 인하여 구조물이 불균일하게 가공되며, 동시에 열팽창계수 차로 인하여 접합된 기판에 큰 휨이 발생한다. 그 결과주파수 차의 분포가 커지고, 동시에 수율은 저하되었다. 이를 개선하기 위하여 SiOG (Silicon On Glass) 기술을 적용하였다. SiOG 공정에서는 접합 후에 기판의 휨을 최소화 하기 위하여 1장의 실리콘 기관과 2장의 유리 기판을 사용하였으며, 노칭을 방지하기 위하여 금속 박막을 사용하였다. 그 결과 노칭 현상이 방지되었으며, 기판의 휨도 감소하였다. 또한 주파수 차의 분포도 매우 균일하게 되었으며, 주파수 차의 편차 또한 개선이 되었다. 그 결과 높은 수율 및 보다 강건한 MEMS 자이로스코프를 개발할 수 있었다. MEMS devices such as a vibratory gyroscope often suffer from a lower yield rate due to fabrication errors and the external stress. In the decoupled vibratory gyroscope, the main factor that determines the yield rate is the frequency difference between the sensing and driving modes. The gyroscope, fabricated with SOI (Silicon-On-Insulator) wafer and packaged using the anodic bonding, has a large wafer bowing caused by thermal expansion mismatch as well as non-uniform surfaces of the structures caused by the notching effect. These effects result in large distribution in the frequency difference, and thereby a lower yield rate. To improve the yield rate we propose a packaged SiOG (Silicon On Glass) technology. It uses a silicon wafer and two glass wafers to minimize the wafer bowing and a metallic membrane to avoid the notching. In the packaged SiOG gyroscope, the notching effect is eliminated and the warpage of the wafer is greatly reduced. Consequently the frequency difference is more uniformly distributed and its variation is greatly improved. Therefore we can achieve a more robust vibratory MEMS gyroscope with a higher yield rate.

Notching is less, if femoral component sagittal positioning is planned perpendicular to distal femur anterior cortex axis, in navigated TKA

( Raj Kanna ) 대한슬관절학회 2021 대한슬관절학회지 Vol.33 No.-

Purpose: In navigated TKA, the risk of notching is high if femoral component sagittal positioning is planned perpendicular to the sagittal mechanical axis of femur (SMX). We intended to determine if, by opting to place the femoral component perpendicular to distal femur anterior cortex axis (DCX), notching can be reduced in navigated TKA. Methods: We studied 171 patients who underwent simultaneous bilateral computer-assisted TKA. Femoral component sagittal positioning was planned perpendicular to SMX in one knee (Femur Anterior Bowing Registration Disabled, i.e. FBRD group) and perpendicular to DCX in the opposite knee (Femur Anterior Bowing Registration Enabled, i.e. FBRE group). Incidence and depth of notching were recorded in both groups. For FBRE knees, distal anterior cortex angle (DCA), which is the angle between SMX and DCX, was calculated by the computer. Results: Incidence and mean depth of notching was less (p = 0.0007 and 0.009) in FBRE versus FBRD group, i.e. 7% versus 19.9% and 0.98 mm versus 1.53 mm, respectively. Notching was very high (61.8%) in FBRD limbs when the anterior bowing was severe (DCA > 3°) in the contralateral (FBRE) limbs. Conclusion: Notching was less when femoral component sagittal positioning was planned perpendicular to DCX, in navigated TKA. Level of evidence: Therapeutic level II.

비성형술 후 발생한 연한삼각의 톱니모양변형에 대한 V-Y 전진피판술을 이용한 교정

이경진,이수향,신동혁,김순흠,엄기일,최현곤 대한미용성형외과학회 2008 Archives of Aesthetic Plastic Surgery Vol.14 No.1

Soft triangle of nose is composed of only two skin layer between dome of alar cartilage and nostril. If soft triangle is damaged in rhinoplasty, the notching deformity can be caused by scar contracture. For correction of notching deformity, some methods such as composite graft or filler injection have been introduced, however these methods have some disadvantages like need for donor site or unpredictable long term results. We could correct notching deformity of soft triangle with V-Y advancement flap on the vestibular skin with great ease. Our method was undergone for 3 patients with notching deformity among 120 patients who had rhinoplasty during from March 2004 to February 2007 in our clinic. The elapse of time to definitive deformity was mean 2 months and the corrective procedure was performed 4 months later after formation of definitive deformity. Under the local anesthesia, the triangular flap proximally based was designed on the vestibular skin and this flap was sutured in V-Y fashion. There was no complication and no recurrence. This method is thought to be very useful because of some advantages: easy controlling advancement of flap according to the severity of deformity, no need for donor site, predictable outcome, and economic.

Development of an Efficient Notching Toolkit for Response Limiting Method

Jo Mun Shin 항공우주시스템공학회 2021 항공우주시스템공학회지 Vol.15 No.4

At launch, satellites are exposed to various types of structural loads, such as quasi-static loads, sinusoidal vibrations, acoustic/random vibrations, and shocks. The launch environment test is aimed at verifying the structural stability of the test object against the launch environment. Various types of launch environments are simulated by simple vibration, acoustic, and shock tests considering possible test conditions in ground. However, the difference between the launch environment and the test environment is one of the causes of excessive testing. To prevent overtesting, a notching technique that adjusts the frequency range and the input load considering the design load is applied. For notching, specific procedures are established considering the satellite development concept, selected launch vehicle, higher system requirements, and test target level. In this study, the notching method, established procedure, and development of a notching toolkit for efficient testing are described.

Prediction of punch life in notching process for automatic transmission retainer considering fatigue and wear

이인규,정명식,이상곤,이성윤,김다혜,이재욱,조영재,최창영,김병민 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.12

In notching process, predicting punch replacement period is very important. The retainer made of thick steel plate is one of the importantcomponents of the automatic transmission. The transmission retainer is produced through a shearing process, such as a piercing ornotching process. In this process, very high stress occurs in the punch because of high strength and thickness of steel plate. Therefore,punch life is very short. In this study, the fatigue and wear life of the punch in notching process is predicted using numerical analysis. Anexperiment was conducted to verify the effectiveness of the result of numerical analysis for predicting the punch life. From the experimentthe fatigue failure of the punch and the wear depth in notching process are measured. From the results the wear and fatigue lifepredicted through numerical analysis agree well with the experimental results.

Notching characteristics of un-doped amorphous silicon in high density plasma etching

Cheon-Kwang Ko,Won Gyu Lee 한국공업화학회 2009 Journal of Industrial and Engineering Chemistry Vol.15 No.2

Notching in un-doped amorphous silicon gate etching, a profile distortion phenomenon, has been studied and analyzed with low pressure, high density plasmas using HBr/Cl2/O2 chemistries. In contrast with the notching phenomenon observed in doped polysilicon etching, a notch was evolved at the outer sidewall foot of the edge line, where the outer sidewall of the edge line was exposed to a microscopic open area. A considerable recess was observed at the upper corner of a trench etched silicon substrate in photoresist-masked gate etching, while an oxynitride-masked gate structure showed little silicon recess at the same region. The subsequent accumulation of ions caused by deflected ions on the oxide surface adjacent to the outermost gate line leads to the formation of a local electric field near the outermost gate line, intensifying the ion trajectory distortion toward the sidewall foot of the outermost gate line. 2009 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.