Effect of Total Hip Arthroplasty on Ipsilateral Lower Limb Alignment and Knee Joint Space Width: Minimum 5-Year Follow-up

Choi Yun Seong,Park Jung-Wee,Kim Tae Woo,Kang Kee Soo,Lee Young-Kyun,Koo Kyung-Hoi,Chang Chong Bum 대한의학회 2023 Journal of Korean medical science Vol.38 No.20

Background: This study aimed to 1) assess the effect of total hip arthroplasty (THA) on coronal limb alignment, namely, the hip–knee–ankle angle (HKA), 2) identify factors that determine changes in the HKA, and 3) determine whether alignment changes influence the knee joint space width. Methods: We retrospectively evaluated 266 limbs of patients who underwent THA. Three types of prostheses with neck shaft angles (NSAs) of 132°, 135°, and 138° were used. Several radiographic parameters were measured in the preoperative and final radiographs (at least 5 years after THA). A paired t-test was used to confirm the effect of THA on HKA change. Multiple regression analysis was performed to identify radiographic parameters related to HKA changes following THA and changes in knee joint space width. Subgroup analyses were performed to reveal the effect of NSA change on the HKA change, and the proportion of total knee arthroplasty usage and changes in radiographic parameters between maintained joint space and narrowed joint space groups were compared. Results: The preoperative mean HKA was 1.4° varus and increased to 2.7° varus after THA. This change was related to changes in the NSA, lateral distal femoral angle, and femoral bowing angle. In particular, in the group with a decrease in NSA of > 5°, the preoperative mean HKA was largely changed from 1.4° varus to 4.6° varus after THA. The prostheses with NSA of 132° and 135° also led to greater varus HKA changes than those with an NSA of 138°. Narrowing of the medial knee joint space was related to changes in the varus direction of the HKA, decrease in NSA, increase in femoral offset. Conclusion: A large reduction in NSA can lead to considerable varus limb alignment after THA, which can have adverse effects on the medial compartment of the ipsilateral knee.

Differences in Resumption of Orthopedic Surgery According to Characteristics of Surgery during COVID-19 Pandemic: National Registry Data

Hyung Jun Park,Moon Jong Chang,Tae Woo Kim,Chong Bum Chang,Seung-Baik Kang 대한정형외과학회 2023 Clinics in Orthopedic Surgery Vol.15 No.2

Background: Healthcare services have been restricted after the coronavirus disease 2019 (COVID-19) outbreak. With the pandemic still ongoing, the patterns of orthopedic surgery might have changed. The purpose of this study was to determine whether the reduced volumes of orthopedic surgery were recovered over time. Among the trauma and elective surgery, which accounted for most orthopedic surgical procedures, we also sought to elucidate whether the changes in the volumes of orthopedic surgery differed according to the type of surgery. Methods: The volumes of orthopedic surgery were analyzed using the Health Insurance Review and Assessment Service of Korea databases. The surgical procedure codes were categorized depending on the characteristics of the procedures. The actual volumes of surgery were compared with the expected volumes to elucidate the effect of COVID-19 on surgical volumes. The expected volumes of surgery were estimated using Poisson regression models. Results: The reducing effect of COVID-19 on the volumes of orthopedic surgery weakened as COVID-19 continued. Although the total volumes of orthopedic surgery decreased by 8.5%–10.1% in the first wave, those recovered to a 2.2%–2.8% decrease from the expected volumes during the second and third waves. Among the trauma and elective surgery, open reduction and internal fixation and cruciate ligament reconstruction decreased as COVID-19 continued, while total knee arthroplasty recovered. However, the volumes of hemiarthroplasty of the hip did not decrease through the year. Conclusions: The number of orthopedic surgeries, which had decreased due to COVID-19, tended to recover over time, although the pandemic was still ongoing. However, the degree of resumption differed according to the characteristics of surgery. The findings of our study will be helpful to estimate the burden of orthopedic surgery in the era of persistent COVID-19.

다양한 골 이식재의 임상 효과에 대한 고찰

이승범,연제영,채경준,정의원,김창성,이용근,조규성,채중규,김종관,최성호,Lee, Seung-Bum,Yon, Je-Young,Chae, Gyung-Joon,Jung, Ui-Won,Kim, Chang-Sung,Lee, Yong-Geun,Cho, Kyoo-Sung,Chai, Jung-Kiu,Kim, Chong-Kwan,Choi, Seong-Ho 대한치주과학회 2007 Journal of Periodontal & Implant Science Vol.37 No.4

Purpose: Various bone graft materials are being used for periodontal tissue regeneration. Th materials are being developed continuously for ideal clinical effects. Therefore, it is necessary to identify the clinical characteristics of each bone graft material through comparing the various bone graft materials statistically and in doing so, proposing a more efficient bone graft material. In this study, the following results were attained through comparing the clinical effects among the bone graft materials, using the statistical method based on the clinical studies published at the department of periodontology of Yonsei hospital. Materials and Method: 6 selected studies of department of Periodontology at Yonsei University Hospital were based on clinical study of bone grafting in intrabony defects. It was compared the clinical parameters among the 6 clinical studies, using the statistical META analysis. Result: When comparing the probing depth reduction, there was a relatively great amount of decease when using the xenograft, Anorganic Bovine Derived Hydroxapatite Bone Matrix/Cell Binding Peptide(ABM/P-15: PepGen $P-15^{(R)}$) and the autogenous bone and absorbable membrane, d, 1-alctide/glycolide copolymer(GC: $Biomesh^{(R)}$). The allogfrafts showed a relatively low decrease in the probing depth and clinical attachment change. It also showed a slight decrease in the bone probing depth. The allografts showed various results according to different bone graft materials. When comparing the ABM/P-15 and bovine bone $powder(BBP^{(R)})$, ABM/P-15 showed a relatively high clinical attachment level and the bovine bone powder showed a relatively high clinical attachment level. The probing depth change and gingival recession change showed a lower value than the mean value between the two bone graft materials. The synthetic bone showed a relatively high decrease in clinical attachment level and periodontal probing depth change. There was a relatively larger amount of gingival recession when using Bioactive Glass(BG) but a relatively low bone regeneration effect was seen. Conclusion: Good restorative results of the periodontal tissue can be attained by applying the various bone graft materials being used today after identifying the accurate clinical effects.

TiN 超硬薄膜의 被覆에 關한 硏究

金鳳杰,金昌煜,金宗範 慶熙大學校 材料科學技術硏究所 1989 材料科學技術硏究論集 Vol.2 No.-

The TiN film was coated by normal pressure chemical vapor deposition method on the Al_(2)O_(3) plate using TiCl_(4). N_(2) and H_(2) obtained from NH_(3) gas. The effect of the deposition time, temperature, N_(2)/H_(2) ratio, TiCl_(4) (g) flew rate and total flow rate of reactant gas on deposition were investigated. The results were as follows. 1. The thickness of TiN thin film was increased linealy with increase of deposition time and TiCl_(4)(g) flow rate. 2. The microhardness of TiN thin film was high (1,950 ㎏_(f)/㎟) when the crystal plane was oriented preferably along (220) plane, and such orientation was prevalent in N_(2)/H_(2) ratio 0.352 and TiCl_(4)(g) flow rate more than 28㎖/min respectively. 3. The rate determining step of the deposition rate was mass transport of reactant gas and apparent activation energy was 9.3㎉/㏖.

封着유리의 製造에 關한 硏究

金鳳杰,金宗範,權昶吾,朴慶煥 慶熙大學校 1988 論文集 Vol.17 No.-

The purpose of these studies are to prepare low melting devitrifiable solder glass for high termal expansion seal and to find out solder glass which is the optimum condition in terms of thermal properties among others. Then five kinds of frits were prepared by quenching after melting of solder glass in the Pt-crucible at 1,100℃, which contained 2wt% of ZrO₂ as a neucleation agent with being control led by the concentration of mother glass of PbO-ZnO-B₂O₃-SiO₂ system. For probing the characteristics of the solder glass, DTA, X-ray powder diffraction, thermal, expansion, sealability, fluidity and activation energy were examined. The results are as follows: 1. It was possible in sealing of low temperature that the sealability & crystallization temperature was lowered and the fludity was good owing to an increase in PbO wt% but it was inadquate in sealing of color TV tube for 80.5wt% PbO and over because thermal expansion was increased. 2. The optimum holding time was 60 minutes. 3. In the sample contained 80.5wt% PbO, the thermal expansion coefficient was 101.8×10^-7/℃, the crystallization temperature was 443℃, flow button diameter was 27.7㎜, the sealability was 25.15㎏f/㎠, It is better than the existing solder glass. 4. The crystals proved in process of melting and crystallization were Pb_8Zn(Si₂O_7)₃, PbZrO, Zn₂SiO₁ etc. 5. The activation energy needed for crystallization was 87.13kJ/mol.

3차원 전산화단층촬영 영상을 이용한 안면 연조직 두께 계측의 임상적 유용성

정호걸,김기덕,한승호,허경석,이제범,박혁,최성호,김종관,박창서 대한구강악안면방사선학회 2006 Imaging Science in Dentistry Vol.36 No.2

Purpose : To evaluate clinical usefulness of facial soft tissue thickness measurement using 3D computed tomographic images. Materials and Methods : One cadaver that had sound facial soft tissues was chosen for the study. The cadaver was scanned with a Helical CT under following scanning protocols about slice thickness and table speed; 3 mm and 3 mm/sec, 5 mm and 5 mm/sec, 7 mm and 7 mm/sec. The acquired data were reconstructed 1.5, 2.5, 3.5 mm reconstruction interval respectively and the images were transferred to a personal computer. Using a program developed to measure facial soft tissue thickness in 3D image, the facial soft tissue thickness was measured. After the ten-time repeation of the measurement for ten times, repeated measure analysis of variance (ANOVA) was adopted to compare and analyze the measurements using the three scanning protocols. Comparison according to the areas was analyzed by Mann-Whitney test. Results : There were no statistically significant intraobserver differences in the measurements of the facial soft tissue thickness using the three scanning protocols (p>0.05). There were no statistically significant differences between measurements in the 3 mm slice thickness and those in the 5 mm, 7 mm slice thickness (p>0.05). There were statistical differences in the 14 of the total 30 measured points in the 5 mm slice thickness and 22 in the 7mm slice thickness. Conclusion : The facial soft tissue thickness measurement using 3D images of 7 mm slice thickness is acceptable clinically, but those of 5 mm slice thickness is recommended for the more accurate measurement.

Transfer of metallic debris from the metal surface of an acetabular cup to artificial femoral heads by scraping: Comparison between alumina and cobalt–chrome heads

Chang, Chong Bum,Yoo, Jeong Joon,Song, Won Seok,Kim, Deug Joong,Koo, Kyung-Hoi,Kim, Hee Joong Wiley Subscription Services, Inc., A Wiley Company 2008 Journal of biomedical materials research. Part B, Vol.b85 No.1

<P>We aimed to investigate the transfer of metal to both ceramic (alumina) and metal (cobalt–chrome) heads that were scraped by a titanium alloy surface under different load conditions. The ceramic and metal heads for total hip arthroplasties were scraped by an acetabular metal shell under various loads using a creep tester. Microstructural changes in the scraped area were visualized with a scanning electron microscope, and chemical element changes were assessed using an energy dispersive X-ray spectrometry. Changes in the roughness of the scraped surface were evaluated by a three-dimensional surface profiling system. Metal transfer to the ceramic and metal heads began to be detectable at a 10 kg load, which could be exerted by one-handed force. The surface roughness values significantly increased with increasing test loads in both heads. When the contact force increased, scratching of the head surface occurred in addition to the transfer of metal. The results documented that metallic debris was transferred from the titanium alloy acetabular shell to both ceramic and metal heads by minor scraping. This study suggests that the greatest possible effort should be made to protect femoral heads, regardless of material, from contact with metallic surfaces during total hip arthroplasty. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008</P>

Relationship Between Coronal Alignment and Rotational Profile of Lower Extremity in Patients With Knee Osteoarthritis

Chang, Moon Jong,Jeong, Hyeon Jang,Kang, Seung-Baik,Chang, Chong Bum,Yoon, Chan,Shin, Joung Youp Elsevier 2018 The Journal of arthroplasty Vol.33 No.12

<P><B>Abstract</B></P> <P><B>Background</B></P> <P>We aimed at determining whether the coronal alignment of lower extremity was related to rotational geometry of distal femur, femoral anteversion, and tibial torsion in patients with knee osteoarthritis.</P> <P><B>Methods</B></P> <P>A total of 422 lower extremities were divided into 3 groups according to the coronal alignment: valgus (n = 31), neutral (n = 78), and varus group (n = 313). Condylar twisting angle was measured to determine rotational geometry of distal femur as the angle between the clinical transepicondylar axis and the posterior condylar line. Femoral anteversion was assessed using the angle between a line intersecting the femoral neck and the posterior condylar line (pFeAV) and the angle between the same line and transepicondylar axis that is not affected by posterior condylar variations (tFeAV). Tibial torsion was evaluated by measuring the angle between the posterior condyles of the proximal tibia and the transmalleolar axis.</P> <P><B>Results</B></P> <P>As the coronal alignment changed from varus to valgus, the condylar twisting angle increased (r = 0.253, <I>P</I> < .001; 6.6° in varus, 7.4° in neutral, and 10.2° in valgus group). Although the pFeAV also increased (r = 0.145, <I>P</I> = .003), the tFeAV did not change significantly (<I>P</I> = .218). Mean tFeAV was 4.3° in varus, 4.7° in neutral, and 6.5° in valgus group. In contrast, as the coronal alignment changed from varus to valgus, the external tibial torsion increased (r = 0.374, <I>P</I> < .001; 22.6° in varus, 26.3° in neutral, and 32.6° in valgus group).</P> <P><B>Conclusion</B></P> <P>The change patterns of the rotational profiles of the lower extremity according to the coronal alignment should be considered in order to obtain satisfactory rotational alignment after TKA.</P>

인공 슬관절 전치환술 시 적절한 대퇴 치환물의 회전 정렬을 위한 원위 대퇴골과 경골의 해부학적 고찰

장종범 ( Chong Bum Chang ),성상철 ( Sang Cheol Seong ),이상훈 ( Sahng Hoon Lee ),이명철 ( Myung Chul Lee ) 대한슬관절학회 2010 대한슬관절학회지 Vol.22 No.1

Purpose: This study aimed 1) to identify the rotational axis of the femur that provides a balanced 90˚ flexion space in TKA, 2) to assess the changes in the flexion space in deep flexion, and 3) to assess the changes in rotational alignment, with using the posterior condylar axis (PCA) as a guide, and as the changes are related to asymmetric cartilage erosion of the posterior condyle. Materials and Methods: The axial MR images of the distal femur in knee extension and the coronal images of the distal femur and the entire tibia at 90 and 130˚ were examined in 40 healthy adults. Results: The clinical transepicondylar axis (TEA) provides a balanced 90˚ flexion space on average. The balanced flexion space in 90˚ became an asymmetrical space with relative narrowing of the medial side in 130˚. Every 1 mm of asymmetrical cartilage erosion between the posterior condyles changed the femoral rotation by approximately 1˚ when using the PCA as a guide. Conclusion: This study suggests that the clinical TEA is the rotational reference that provides a balanced flexion space. When using the PCA as a rotational reference, a surgeon should consider the potential change in the rotational angle that is caused by asymmetrical cartilage erosion.

Concomitant Ankle Osteoarthritis Is Related to Increased Ankle Pain and a Worse Clinical Outcome Following Total Knee Arthroplasty :

Chang, Chong Bum,Jeong, Jin Hwa,Chang, Moon Jong,Yoon, Chan,Song, Min Kyu,Kang, Seung-Baik Journal of Bone and Joint Surgery 2018 Journal of bone and joint surgery Vol.100 No.9

<P>Conclusions: A considerable proportion of patients who underwent TKA had concomitant ankle OA with reduced flexibility of the hindfoot. These patients experienced increased ankle pain following TKA and a worse clinical outcome.</P>