Analysis of changes in tibial torsion angle on open-wedge high tibial osteotomy depending on the osteotomy level

( In-soo Song ),( Junhan Kwon ) 대한슬관절학회 2022 대한슬관절학회지 Vol.34 No.-

Purpose: This study evaluated the tibial torsional angle changes of 72 knees before and after open-wedge high tibial osteotomy (OWHTO) and compared the results according to the osteotomy level. Materials and methods: Seventy patients (72 knees) with Kellgren-Lawrence grade 3 underwent OWHTO. Demographic data, operation procedures, and measurement of mechanical tibiofemoral angle (mTFA), anatomical tibiofemoral angle (aTFA), tibial torsional angle (TTA), and pre- and postoperative Lysholm and International Knee Documentation Committee (IKDC) scores were obtained. The authors analyzed TTA changes between 30 knees with high-level osteotomy (group A) and 42 knees with low-level osteotomy (group B). Results: The changes of TTAs in the subjects of 72 knees went from 29.26 ± 5.6° preoperative mean to 25.36 ± 6.4° postoperative mean (p = 0.032). The postoperative TTAs of group A (mean 27.4 ± 4.8°) and B (mean 25.7 ± 4.9°) were statistically significant (p < 0.01). Preoperative Lysholm and IKDC scores of 72 knees had means of 49.1 ± 3.5 and 49.0 ± 15.2, respectively, and postoperative means of 85.7 ± 8.56 and 78.0 ± 17.6, respectively, which were statistically significant (p < 0.01). Conclusions: Changes of TTA with internal rotation of distal tibia were observed following OWHTO. High-level osteotomy on the proximal tibia’s lateral cortex had less internal rotation of the distal tibia than low-level osteotomy.

Stress analysis of the tibial plateau according to the difference of blade path entry in opening wedge high tibial osteotomy

이준우,Yuan-Zhu Xin,지종훈,Karnav Panchal,권오수,양석조 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.3

High tibial osteotomy (HTO) has been used to successfully treat patients with genu varus deformities that can improve mechanicalfunction and condition in the knee joint. Clinical studies have reported that bow legs often occur with a concentrated load on the varus ofthe tibia. This study aimed to analyze and verify the clinical test data result by utilizing the three-dimensional (3D) static finite elementmethod (FEM). The 3D model of lower extremities, which include the femur, tibia, meniscus, and knee articular cartilage, was createdusing the images from a computer tomography scan and magnetic resonance imaging. In this report, we compared changes in stress distributionand force reaction on the tibial plateau because of critical problems caused by unexpected changes in the tibial posterior-slopeangle because of HTO. The results showed that the 5° wedge-angle virtual opening wedge HTO without and with the posterior-slopeangle shows has a load concentration of approximately 60% and 45% in the medial region, respectively.

유한요소법 기반 개방형 고위경골 절골술 시 골절 유형에 따른 경골의 생체역학적 거동 분석

심온,이승준,이치승 대한기계학회 2023 大韓機械學會論文集B Vol.47 No.12

개방형 고위경골 절골술은 환자의 내반 변형이 동반된 슬관절의 내측 구획 관절염의 치료로 널리 사용되고 있다. 관절염으로 고통받는 환자의 인공 관절 치환술을 지연시킬 수 있고 내측 구획의 섬유 연골 재생에 좋은 치료법이다. 그러나 해당 수술법을 행할 시에 형성하는 경첩 부분에서 골절이 발생하여 골이식이 필요해질 수 있는데 이에 관한 연구는 미미하다. 그렇기에 본 연구에서는 내측 개방형 고위경골 절골술을 행할 때 발생할 수 있는 경첩 골절의 형상에 따라 경골에 작용하는 응력 변화를 분석하였다. 결과적으로 모든 골절 모델에서 피질골과 해면골에 작용하는 von Mises 등가 응력의 최댓값과 평균값이 증가하는 것을 확인하였다. 또한, 절골선 상방으로 골절된 모델보다 하방으로 골절된 모델에서 해면골에 작용하는 응력이 높게 측정된 것을 확인하였다. Opening wedge high tibial osteotomy is widely used to treat medial compartment arthritis of the knee joint with varus deformity in patients. It can delay artificial joint replacement in patients suffering from arthritis and is a good treatment for fibrocartilage regeneration of the medial compartment. However, fractures may occur in the hinge part formed when performing the osteotomy, and bone grafting may be required; however, research on this is insignificant. Therefore, in this study, the change in the stress acting on the tibia was analyzed according to the shape of the fracture that might occur during opening wedge high tibial osteotomy. Consequently, the maximum and average values of the von Mises equivalent stress acting on cortical and cancellous bones were confirmed to increase in all fracture models. In addition, the stress acting on the cancellous bones was measured higher in the model with a fracture below the inclination angle than in the model with a fracture above the inclination angle.

Biomechanical Study of the Fixation Plates For Opening Wedge High Tibial Osteotomy

( Kug Jin Kim ),( Eun Kyoo Song ),( Jong Keun Seon ),( Jong Hwan Seol ) 대한슬관절학회 2015 대한슬관절학회지 Vol.27 No.3

Purpose: The purpose of this study was to compare the mechanical stability of three types of plate systems for opening wedge high tibial osteotomy. Materials and Methods: Forty-eight fresh frozen porcine tibia specimens were assigned to three different fixation device groups: Aescular group (16 specimens) was fixed with Aescular plates; Puddu group (16 specimens) with a Puddu plate, and TomoFix group (16 specimens) with a TomoFix plate. We compared axial displacements under compression loads from 200 to 2,000 N and maximal loads at failure among 8 specimens per group. We also compared displacements under cyclic load after 100 cycles at a compressive load of 2,000 N among 8 specimens per group. Results: In all three groups, displacement under compression load increased with the increase in the axial compressive load; however, no significant intergroup differences were observed in the mean values under tested loading conditions. The mean maximal loads at failure were not significantly different (6,055, 6,798, and 6,973 N in the Aescular, Puddu, and TomoFix groups, respectively; p=0.41). While the TomoFix group showed less extension and strain during the cyclic load test, the mean values showed no significant differences among groups. Conclusions: All three plate systems were found to provide fixation stability suitable for bearing axial compression and cyclic loads while walking.

Preoperative flexion contracture is a predisposing factor for cartilage degeneration at the patellofemoral joint after open wedge high tibial osteotomy

Otsuki Shuhei,Ikeda Kuniaki,Wakama Hitoshi,Okuno Nobuhiro,Okamoto Yoshinori,Okayoshi Tomohiro,Miyamoto Yuki,Neo Masashi 대한슬관절학회 2020 대한슬관절학회지 Vol.32 No.-

The purpose of the study was to determine the effect of cartilage degeneration at the patellofemoral joint on clinical outcomes after open wedge high tibial osteotomy and to investigate the predisposing factors for progressive patellofemoral cartilage degeneration.Seventy-two knees were evaluated on second-look arthroscopy in patients who opted for plate and screw removal at an average of 20.1 months after osteotomy. Cartilage degeneration at the patellofemoral joint was evaluated using the International Cartilage Repair Society grading system, with cases divided into progression and nonprogression groups. Radiographic parameters of the patellofemoral anatomy, knee range of motion, and clinical outcomes were evaluated from the preoperative baseline to the final follow up, on average 50 months after osteotomy. A contracture > 5° was considered a flexion contracture. Cartilage degeneration progressed in 31 knees, and preoperative knee flexion contracture was significantly associated with progressive degeneration ( P < 0.01). The Lysholm and Kujala scores were significantly lower in the progression group (87.9 and 85.3, respectively) than in the nonprogression group (91.6 and 93.6, respectively) ( P < 0.05). The odds ratio of the flexion contracture resulting in progression of patellofemoral cartilage degeneration was 4.63 (95% confidence interval, 1.77–12.1). No association was detected between progressive degeneration and age, sex, body mass index, Kellgren-Lawrence grade, or radiographic parameters. Flexion contracture may be associated with progression of cartilage degeneration at the patellofemoral joint and may negatively affect the clinical outcomes after open wedge, high tibial osteotomy.

How to achieve an optimal alignment in medial opening wedge high tibial osteotomy?

( Byoung Youl Kang ),( Do Kyung Lee ),( Hyeon Soo Kim ),( Joon Ho Wang ) 대한슬관절학회 2022 대한슬관절학회지 Vol.34 No.-

Medial opening wedge high tibial osteotomy (MOWHTO) is a widely used surgical treatment option for medial compartmental osteoarthritis with varus deformity. It is important that proper lower limb alignment is achieved. However, there has been no consensus about an optimal alignment in MOWHTO. Most studies suggest that achieving valgus alignment is necessary, and recent studies support slight valgus mechanical alignment of less than 3° of mechanical femorotibial angle. Overcorrection and undercorrection is not recommended for achieving good surgical outcomes. To prevent undercorrection and overcorrection in MOWHTO, the method of placing the weight-bearing line in the target range must be precise. There are several ways to place a weight-bearing line within the target range. While the most important factor for a successful MOWHTO is achieving an ideal mechanical axis correction, there are a few other factors to consider, including joint line obliquity, posterior tibial slope, ligament balancing, and patellar height. Several factors exist that lead to undercorrection and overcorrection. Preoperative amount of varus deformity, lateral hinge fracture, and fixation failure can result in undercorrection, while medial soft tissue laxity and the amount of correction angle and target point beyond hypomochlion can result in overcorrection. This study aimed to review the literature on optimal alignment in MOWHTO and report on the factors to be considered to prevent correction errors and how to achieve an optimal alignment.

Biomechanical Analysis of a Novel Wedge Locking Plate in a Porcine Tibial Model

Jeong-Ku Ha,Chul Hyun Yeom,Ho Su Jang,Han-Eui Song,이성재,Kang Hee Kim,정규성,Mahendar Gururaj Bhat,김진구 대한정형외과학회 2016 Clinics in Orthopedic Surgery Vol.8 No.4

Background: The purpose of this study was to analyze biomechanical properties of a novel wedge locking plate in medial open wedge high tibial osteotomy (OWHTO) in a porcine tibial model. Methods: A uniform 8-mm OWHTO was performed in 12 porcine tibiae. Six of them were subsequently fixed with the plate without a wedge, whereas the other 6 were additionally reinforced with a metal wedge of 8 mm. Biomechanical properties (stiffness, displacement of the osteotomy gap, and failure load) were evaluated under axial load. The different modes of failure were also investigated. Results: The plate showed an axial stiffness of 2,457 ± 450 N/mm with a wedge and 1,969 ± 874 N/mm without a wedge. The maximum failure load was 5,380 ± 952 N with a wedge and 4,354 ± 607 N without a wedge. The plate with a wedge had a significantly greater failure load and significantly less displacement of medial gap at failure than that without a wedge (p = 0.041 and p = 0.002, respectively). The axial stiffness was not different between the two types of fixation. Most failures were caused by lateral cortex breakage and there was no implant failure. Conclusions: The novel wedge locking plate showed excellent biomechanical properties and an additional wedge provided significant improvement. This plate can be a good fixation method for OWHTO.

Analysis of radiographic factors affecting the significant differences in knee alignment between hip-to-talus and hip-to-calcaneus radiographs after opening-wedge high tibial osteotomy

( Hyung Jun Park ),( Joon Hyeok Boo ),( Dong Hun Suh ),( Jae Gyoon Kim ) 대한슬관절학회 2023 대한슬관절학회지 Vol.35 No.-

Background Optimal alignment after opening-wedge high tibial osteotomy (OWHTO) is crucial for obtaining good clinical results. A hip-to-calcaneus radiograph (HCR) appears to reflect the true mechanical axis. However, no study has been reported using the HCR in patients who underwent OWHTO. We aimed to analyze the radiographic factors affecting the significant difference in the weight-bearing line (WBL) ratio between two radiographs after openingwedge high tibial osteotomy (OWHTO). Methods This retrospective study included 51 patients who underwent both hip-to-talus radiographs (HTR) and HCR after OWHTO. The patients were divided into two groups; a consistent group (WBL ratio difference between postoperative HTR and HCR < 5%; N = 35) and an inconsistent group ( > 5%; N = 16). Radiographic variables for lower extremity alignment, knee and ankle joints, and clinical scores were evaluated. The receiver operating characteristic curve was used to determine the threshold of radiographic variables that induced inconsistencies between the two radiographs. Results The mean postoperative WBL ratio in the HCR of the inconsistent group was significantly higher than that of the consistent group (57.7 ± 13.2% and 49.1 ± 11.6%, respectively) (P = 0.02). The preoperative and postoperative ankle joint line obliquity (AJLO) and preoperative lateral distal tibia ground surface angle (LDTGA) were significantly different between the two groups (P < 0.05). The preoperative AJLO (odds ratio 0.784, confidence interval 0.655-0.939, P = 0.008) significantly affected WBL ratio inconsistency. The cutoff value of the preoperative AJLO was 3.16°. However, clinical scores did not differ significantly between the two groups. Conclusion The pre-and postoperative AJLO and the preoperative LDTGA were significantly different between the two groups. Among these variables, only preoperative AJLO negatively affected the inconsistency in WBL ratios between the two radiographs (HTT and HTC). Therefore, it should be considered to prevent postoperative overcorrection of the true mechanical axis after OWHTO, even though we corrected it properly.

Navigation assisted High Tibial Open Wedge Osteotomy

Ji-Hoon Bae,Joon-Ho Wang,Dae-Hee Lee,Cheol-Woong Kim 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

The purpose of this study was to investigate factors affecting the change of tibial posterior slope and introduce a mathematical model which calculate, through 3-dimensional analysis of the proximal tibia, how the angle of the opening wedge along the anteromedial tibial cortex influences the tibial posterior slope and valgus correction when performing a medial open wedge osteotomy. This mathematical model with navigation system can be guidelines which provide surgeons on preoperative and intraoperative measurements to maintain or correct the tibial slope and to obtain the desired valgus correction of the lower limb during an opening wedge osteotomy.

슬관절 골관절염에서 개방형 경골 근위부 절골술과 관절경적 수술 후 결과

전철홍(Churl Hong Chun),김정우(Joung Woo Kim),박진영(Jin Young Park),김채근(Chae Gun Kim) 대한정형외과학회 2006 대한정형외과학회지 Vol.41 No.4

목적: 슬관절 내측 대퇴 경골 구획 퇴행성 관절염 환자에서 개방형 경골 근위부 절골술 및 관절경 치료 후 2년 이상 추시한 환자에서 후향적으로 임상결과 및 방사선학적 분석을 하였다. 대상 및 방법: 1999년 1월부터 2002년 5월까지 개방형 경골 근위부 절골술 및 관절경술을 시행받은 29명 30예를 대상으로 하였다. 평균 추시 기간은 3년 9개월(2년 1개월-5년 4개월)이었고, 평균연령은 44.7 (20-56)세였다. 개방성 절골 간격이 1 ㎝ 이상 4예에서는 Puddu 금속판 고정과 tricortical 자가골 이식술을 시행하였고, 1㎝ 이하 26예에서는 Puddu 금속판을 이용한 고정술만 시행하였다. 임상적 평가는 HSS 슬관절 점수를 사용하였으며, 방사선적 분석은 체중 부하 시 촬영한 전후면 방사선 사진에서 대퇴 경골각 및 후 경골각을 측정하였다. 결과: HSS 슬관절 점수상 수술 전 평균 64.7 (52.0-69.5)점에서 최종추시 시 82.4 (78-90)점이었다. 방사선 소견상 모든 예에서 골유합은 이루어졌으며, 수술 전 체중부하 전후면 방사선 사진상 평균 6.3 (3.5-8.0)도 내반각에서 수술 직후 평균 8.2 (5-10)도 외반각으로, 최종 추시상 외반각은 평균 7.3 (4.5-9.0)도로 교정되었다. 후경골각의 변화는 수술 전 평균 6.6 (5.0-7.3)도에서 추시상 평균 7.0 (5.0-8.5)도로 유의한 차이는 없었다(p=0.075). 방사선 소견 및 2차 관절경 소견상 더 이상의 진행변화 소견은 없었다. 결론: 개방형 경골 근위부 절골술과 함께 관절경을 이용한 슬관절내 병변을 치료하여, 향상된 슬관절 기능을 얻을 수 있었다. Purpose : To evaluate the clinical and radiographic outcomes of high tibial open wedge osteotomy combined with arthroscopic surgery in patients with medial unicompartmental osteoarthritis. Materials and Methods : Between January 1999 and May 2002, 29 patients with 30 cases were treated with high tibial open wedge osteotomy combined with arthroscopic surgery for the treatment of osteoarthritis. The mean age of the study group was 44.7 years old (range, 20 to 56 years old). 4 cases with more than 1 cm openings were treated by autologous bone grafts, and another 26 cases were treated by Puddu plates alone after osteotomy. The clinical assessment was performed using the Hospital for Special Surgery (HSS) knee rating system. The radiologic analysis was performed by measurement of the femorotibial angle and posterior inclination of the tibial articular surface. Results : The mean knee rating score by the HSS knee rating system improved from 64.7 points (range, 52.0 to 69.5 points) to 82.4 points (range, 78 to 90) at the last follow-up. Radiologic bone union was accomplished in all cases. Preoperative varus angles of 6.3° (range, 3.5 to 8.0 degrees) and posterior inclinations of 6.6° (range, 5.0 to 7.3 degrees) improved, on average, to postoperative valgus angles of 8.2° (range, 5 to 10 degrees) and posterior inclinations of 7° (range, 5.0 to 8.5 degrees). At the last follow-up valgus angles had improved, on average, to 7.3° (range, 4.5 to 9.0 degrees). Conclusion : High tibial open wedge osteotomy combined with arthroscopic surgery significantly improved knee joint function.