• Korean Journal of Computational Design and Engineering
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• v.16 no.5
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• pp.315-322
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• 2011

The goal of total knee replacement (TKR) surgery is to replace patient's knee joint with artificial implants in order to restore normal knee joint functions. Since mismatched knee implants often cause a critical balancing problem and short durability, designing a well-fitted implant to a patient's knee joint is essential to improve surgical outcomes. We developed a software system that three-dimensionally (3D) simulates TKR surgery based upon 3D knee models reconstructed from computed tomography (CT) imaging. The main task of the system was to extract precise 3D anatomical parameters of a patient's knee that were directly used to determine a custom fit implant and to virtually perform TKR surgery. The virtual surgery was simulated by amputating a 3D knee model and positioning the determined implant components on the amputated knee. The test result shows that it is applicable to derive surgical parameters, determine individualized implant components, rehearse the whole surgical procedure, and train medical staff or students for actual TKR surgery. The feasibility and verification of the proposed system is described with examples.

• Knee surgery & related research
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• v.30 no.4
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• pp.319-325
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• 2018

Purpose: Body mass index (BMI) is often used to predict surgical difficulty in patients receiving total knee arthroplasty (TKA); however, BMI neglects variation in the central versus peripheral distribution of adipose tissue. We sought to examine whether anthropometric factors, rather than BMI alone, may serve as a more effective indication of surgical difficulty in TKA. Materials and Methods: We prospectively enrolled 67 patients undergoing primary TKA. Correlation coefficients were used to evaluate the associations of tourniquet time, a surrogate of surgical difficulty, with BMI, pre- and intraoperative anthropometric measurements, and radiographic knee alignment. Similarly, Knee Injury and Osteoarthritis Outcome Score (KOOS) was compared to BMI. Results: Tourniquet time was significantly associated with preoperative inferior knee circumference (p=0.025) and ankle circumference (p=0.003) as well as the intraoperative depth of incision at the quadriceps (p=0.014). BMI was not significantly associated with tourniquet time or any of the radiographic parameters or KOOS scores. Conclusions: Inferior knee circumference, ankle circumference, and depth of incision at the quadriceps (measures of peripheral obesity) are likely better predictors of surgical difficulty than BMI. Further study of alternative surgical indicators should investigate patients that may be deterred from TKA for high BMI, despite relatively low peripheral obesity.

• Journal of Trauma and Injury
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• v.29 no.4
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• pp.167-171
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• 2016

Irreducible traumatic knee dislocation is rare. The knee dislocation is classified depending on the incarcerated structures. Complete reduction is achieved by extracting the incarcerated structure. Several reports introduce the reduction of irreducible traumatic knee dislocation by open surgery or arthroscopy. This case describes irreducible posterolateral knee dislocation with interposition of the vastus medialis. Closed reduction failed in the emergency room, and complete reduction was attained by arthroscopically sectioning the muscle and fascia of the vastus medialis in the intercondylar notch.

• Journal of Korean Foot and Ankle Society
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• v.22 no.3
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• pp.100-104
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• 2018

Purpose: An axillary crutch is the most commonly used assistive device in foot and ankle patients who require nonweightbearing. On the other hand, its use frequently induces axillary or wrist pain and critical neurovascular injuries have been reported in several studies. This study compared the clinical outcomes of patients using the knee walker and axillary crutch. Materials and Methods: A retrospective analysis was performed comparing the utility of a knee walker and axillary crutch as a nonweightbearing ambulatory aid for 62 foot and ankle patients treated between November 2016 and March 2018. A comparative study of the two orthosis could be performed because all the patients temporarily used an axillary crutch before or after the use of a knee walker. A demographic study and comparative analysis based on the visual analogue scale (VAS) satisfaction score (0~100), complications, and fall down history were evaluated. Furthermore, under the assumption of having retreatment, their preference of orthosis between the knee walker and axillary crutch was investigated. Results: The mean age of the patients was 36.5 and the mean duration of ambulation with a knee walker and axillary crutch were 5.2 and 2.4 weeks. The VAS satisfaction score of the knee walker and crutch was 88.8 and 27.5, respectively (p<0.05). The most frequent complications of the knee walker and crutch were ipsilateral knee pain (6 cases) and axillary or wrist pain (56 cases), respectively. No case of falling down occurred during knee walker ambulation, but there were two cases of crutch ambulation. Fifty-eight patients (93.5%) preferred the knee walker and four patients (6.5%) preferred a crutch. Conclusion: Compared to the axillary crutch, the knee walker afforded lower complication and higher satisfaction. Most patients preferred the knee walker to a crutch. Therefore, the knee walker is an efficient and safe orthosis for foot and ankle patients who require nonweightbearing.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.11 no.1
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• pp.39-44
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• 2013

Purpose : The purpose of present study is to evaluate the joint angles of legs in the standing posture for six patients with unilateral knee osteoarthritis. Methods : The participants underwent unilateral total knee replacement. A motion analysis was used to measure the joint angles of the hip, knee, and ankle. The measurements were taken before the surgery, one week and two weeks after the surgery. Both sides of the legs were evaluated. Results : This result showed that after a certain healing period, both hip joint angles showed a significant difference while there was no significant difference in the knee and ankle joint angles. After surgery, the angle of ankle dorsiflexion was smaller on the operated side than the opposite side compared to the pre-surgery measurements. Conclusion : After surgery, the asymmetry in a standing position left unchanged due to contracture of the knee joint and tightness in the hamstring muscle. Therefore, when physiotherapists plan an initial exercise programs for TKR patients, it is essential to apply adequate exercises which consider the contracture of the leg joints.

• Knee surgery & related research
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• v.30 no.4
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• pp.311-318
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• 2018

Purpose: The purpose of this study was to evaluate changes in the coronal alignment of the knee and ankle joints after open wedge high tibial osteotomy (OWHTO) to determine factors related to the recurrence (R) of the varus deformity by serial analysis. Materials and Methods: Sixty-four OWHTOs were enrolled in this study. The weight bearing line (WBL) ratio, joint line convergence angle (JLCA), knee joint inclination, mechanical axis-tibial plateau angle, talar inclination (TI), and distal tibia articular angle (DTAA) were serially assessed. Serial correlation analysis between all parameters was performed. Patients were divided into R group and no recurrence (NR) group according to the WBL ratio (55%) at postoperative one year. Results: The preoperative WBL ratio showed significantly negative correlation with serial changes of JLCA, TI, and DTAA (p<0.05). The JLCA, TI, and DTAA as well as WBL ratio showed a significantly larger degree of varus alignment in the R group than in NR group at postoperative 6 weeks and 1 year after OWHTO (p<0.05). Conclusions: Sufficient correction of the WBL and restoration of the JLCA during OWHTO are essential to prevention of the R of varus deformity after the surgery because they are the only modifiable factors during surgery. Level of Evidence: IV, Case series.

• Journal of Korean Foot and Ankle Society
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• v.11 no.2
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• pp.135-140
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• 2007

Purpose: To evaluate the incidence and describe radiologic pattern of ankle arthritis following change of mechanical loading axis by total knee arthroplasty. Materials and Methods: We reviewed radiographs of 419 cases, 243 patients underwent total knee arthroplasy from January 2002 to October 2006 retrospectively. We described radiologic parameters around the ankle joint and measured the amount of change of knee varus or valgus angle by comparing preoperative and postoperative anteroposterior standing lower extremities AP X-rays. We divided cases into two groups, one with radiologically arthritic change of the ankle joint and the other one without any radiologic change after surgery. We compared two groups in each parameters and analyzed statistically (SPSS v13.0). Results: Three hundred eighty one cases were divided into varus group and 38 cases in valgus group. 125 cases were divided into ankle arthritic change-positive subgroup among the varus group and 251 cases were in negative subgroup. The amount of varus angle correction by total knee arthroplasty showed significant difference between two subgroups. There was no significant difference in each parameters between subgroups within 38 valgus cases. Conclusion: Ankle arthritis can be aggravated after total knee arthroplasty because of the change of mechanical loading axis onto the ankle joint. Therefore it may be needed to evaluate symptoms and function of ankle joints before performing total knee arthroplasties especially in patients with huge varus deformities of knee joints.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.93-99
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• 2005

In spite of proper maneuver of total knee replacement arthroplasty, some patients suffer from skin necrosis just above the implant. From Mar. 2000 to Jan. 2004, the authors performed reconstruction of knee skin defects after total knee replacement athroplasty. Total 6 cases of flap surgery were performed and patients ranged between 43-years-old to 82-years-old. Rectus femoris perforator based reversed adipofascial flaps were used in 2 cases, medial gastrocnemius muscular island flaps were used in 2 cases and sural artery based on adipofascial rotation flap was used in 1 case. One patient with extended necrosis underwent reconstruction with dual flaps of sural artery based adipofascial rotation flap and medial gastrocnemius muscular island flap. There were no distinctive complication needing additional procedure in all cases during the long term follow up. Reconstruction of necrosis following total knee replacement arthroplasty had several characteristics different from simple knee defect. The patients might have the history of long term steroid usages, excessive skin tension due to implants, underlying disease such as diabetes, rheumatoid disease, and etc. In addition, the early ambulation is mandatory in these patients of total knee replacement arthroplasty. With regards to these special considerations, a single stage and reliable operation must be needed. The authors introduce various reconstruction methods and algorithm that may aid easy decision making.

• Physical Therapy Rehabilitation Science
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• v.8 no.1
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• pp.22-31
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• 2019

Objective: For knee osteoarthritis (OA), there is a demand for alternative modalities in order to delay surgery and to avoid the side effects of medications. This study compared the effects of applying seaweed pack and mudpack for the treatment of knee OA. Design: Randomized controlled trial. Methods: Twenty-five patients with knee OA who satisfied the criteria were included. The patients were divided into two groups according to the treatment method: mudpack (n=12) and seaweed pack (n=13). The two groups were treated for 20 minutes, twice a day for five continuous days at the Ocean Healing Center at Wando Island, South Korea. Participants were assessed by clinical scores (Western Ontario and McMaster Universities Osteoarthritis Index, Hospital for Special Surgery Knee Score, Knee injury and Osteoarthritis Outcome Score and 36-Item Short Form Health Survey) and lab results (erythrocyte sedimentation rate, C-reactive protein, insulin-like growth factor-1 [IGF-1], tumor necrosis $factor-{\alpha}$ [$TNF-{\alpha}$]) during the follow-up period. Results: For the most part, clinical scores improved after therapy and maintained improvements for four weeks in both groups (p<0.05). In the seaweed group, $TNF-{\alpha}$ was significantly decreased at two weeks post-therapy (p<0.05). In both groups, IGF-1 was significantly increased immediately post-therapy (p<0.05). There were no statistically significant differences after therapy between the groups in clinical scores and labs. Conclusions: Seaweed packs and mudpacks had similar positive effects for knee OA. Additionally, the seaweed pack group showed decreased levels of $TNF-{\alpha}$ at two weeks post-treatment, which may explain the reduced inflammatory reaction. For rehabilitation therapy, use of seaweed packs may serve as an alternative modality for the treatment of knee OA.

• Physical Therapy Rehabilitation Science
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• v.8 no.3
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• pp.170-174
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• 2019

Objective: The objective of this study was to investigate the differences in the quality of life between two groups of patients who received or did not receive total knee replacement (TKR) surgery after being diagnosed with knee osteoarthritis (OA), and to investigate changes in the quality of life for persons who had TKR surgery. Design: Cross-sectional study. Methods: The subjects were randomized into a surgery group (n=70) and a non-surgery group (n=65). Subjects were selected from individuals diagnosed with knee OA from Himchan Hospital in Seoul, South Korea. Their sex, age, weight, height, body mass index, unilateral or bilateral, and quality of life were evaluated. Changes in the quality of life was measured using the Short Form-36 Health Survey (SF-36). Seventy out of 135 patients had TKR surgery, and their quality of life was evaluated at 6 months and 12 months after the surgery. Results: SF-36 scores were significantly improved at 6 months and 12 months after the surgery compared to the scores before the surgery (p<0.05). Also, the comparison between 6 and 12 months after surgery showed that the Vitality and Social Function scores in the SF-36 were significantly increased (p<0.05). Conclusions: The findings of this study showed that TKR surgery has a positive effect on the quality of life for persons with knee OA as a therapeutic intervention.