Won Chul Choi - Academia.edu (original) (raw)

Papers by Won Chul Choi

Research paper thumbnail of Comparison between standard and high-flexion posterior-stabilized rotating-platform mobile-bearing total knee arthroplasties: a randomized controlled study

The Journal of bone and joint surgery. American volume, Jan 17, 2010

A high-flexion posterior-stabilized rotating-platform mobile-bearing prosthesis was designed in a... more A high-flexion posterior-stabilized rotating-platform mobile-bearing prosthesis was designed in an attempt to improve the range of motion after total knee arthroplasty without compromising the theoretical advantages of the posterior-stabilized rotating-platform mobile-bearing system. The aim of this study was to compare the outcomes of standard and high-flexion posterior-stabilized rotating-platform mobile-bearing total knee arthroplasties. One hundred and seventy knees were randomly allocated to receive either a standard (n = 85) or a high-flexion (n = 85) posterior-stabilized rotating-platform mobile-bearing prosthesis and were followed prospectively for a minimum of two years. Ranges of motion, functional outcomes determined with use of standard scoring systems, and radiographic measurements were assessed. In addition, patients' abilities to perform activities requiring deep knee flexion and patient satisfaction were evaluated with use of questionnaires. The average postopera...

Research paper thumbnail of Preservation of the posterior cruciate ligament is not helpful in highly conforming mobile-bearing total knee arthroplasty: a randomized controlled study

Knee Surgery, Sports Traumatology, Arthroscopy, 2012

Purpose The purpose of this study is to investigate whether the preservation of the posterior cru... more Purpose The purpose of this study is to investigate whether the preservation of the posterior cruciate ligament (PCL) can be helpful for improving kinematics and clinical outcome in highly conforming mobile-bearing total knee arthroplasty (TKA). Methods Ninety osteoarthritic knees were randomly allocated to either the PCL-preserving group or the PCLsacrificing group. Passive kinematics was recorded with a navigation system immediately after implantation. Three parameters (anterior/posterior translation, varus/valgus rotation, and internal/external rotation) were analysed from 0°to 120°flexion. Results The PCL-preserving group (42 knees) had more varus rotation over 90°flexion (p \ 0.05) and more anterior translation of the femur in all ranges of flexion (p \ 0.05) than those in the PCL-sacrificing group (44 knees). There was no difference in the internal/external rotation (p [ 0.05). The range of motion, functional scores, and radiographic results did not significantly differ between the two groups at the final follow-up. Three knees in the PCL-preserving group were revised: two presented with instability caused by traumatic attenuation of the PCL and one with subluxation of the insert due to a tight PCL. Conclusion The preservation of the PCL was not helpful for improving kinematics and clinical outcome in highly conforming mobile-bearing TKA. Level of evidence II.

Research paper thumbnail of Painful Patellar Clunk or Crepitation of Contemporary Knee Prostheses

Clinical Orthopaedics & Related Research, 2012

Background Painful patellar clunk or crepitation (PCC) is a resurgent complication of contemporar... more Background Painful patellar clunk or crepitation (PCC) is a resurgent complication of contemporary posterior-stabilized TKA. The incidence, time to presentation, causes, and treatment of PCC still remain controversial. Questions/purposes We therefore (1) compared the incidence of PCC with five contemporary TKA designs, (2) evaluated the time to presentation, (3) identified possible etiologies, and (4) determined recurrence rate and change in knee functional scores after treatment for PCC. Methods We reviewed 580 patients who had 826 posteriorstabilized TKAs involving five different designs. The incidences of PCC were compared among the prostheses. The knees were divided into two groups depending on the development of PCC, and possible etiologic factors of PCC, including prosthesis design and surgical or radiographic variables, were compared between groups. We investigated the onset time of PCC and evaluated treatment results by knee outcome scores. Minimum followup was 2.0 years (mean, 3.9 years; range, 2.0-9.8 years). Results The PCC incidence was higher in the Press-Fit Condylar 1 Sigma 1 Rotating Platform/Rotating Platform-Flex Knee System (11 of 113 knees, 9.7%) than in the others (seven of 713 knees, 1.0%). Increased risk of PCC was associated with using a specific prosthesis and patellar retention. PCC occurred in all cases within a year after TKA (mean, 7.4 months). Arthroscopic treatment (16 knees) and patellar replacement (two knees) improved knee scores, with no recurrence observed over an average followup of 29 months. Conclusions Prosthesis design and patellar retention were associated with PCC. Surgery resolved the PCC. Level of Evidence Level III, therapeutic study. See Instructions to Authors for a complete description of levels of evidence.

Research paper thumbnail of Plain Radiograph Fails to Reflect the Alignment and Advantages of Navigation in Total Knee Arthroplasty

The Journal of Arthroplasty, 2011

The study purposed to determine if a navigation in total knee arthroplasty (TKA) leads to accurat... more The study purposed to determine if a navigation in total knee arthroplasty (TKA) leads to accurate limb alignment and component position than the conventional technique as measured by full length standing radiographs and to evaluate the correlation between navigation and radiographic measurements. A total of 160 knees underwent navigation (n = 80) or conventional (n = 80) TKAs. The frontal femoral alignment was more accurate in navigation TKAs, whereas mechanical axis and frontal tibial alignment were similar in both techniques. Although the intraoperative navigation alignment showed no outliers, postoperative radiographic measure resulted as much as 20% of outliers, and there was no correlation between the two measurements. This lack of correlation and inherent limitations in measuring TKA alignment may bring to question if plain radiograph are useful to determine if alignment achieved by navigation is accurate.

Research paper thumbnail of Comparison between standard and high-flexion posterior-stabilized rotating-platform mobile-bearing total knee arthroplasties: a randomized controlled study

The Journal of bone and joint surgery. American volume, Jan 17, 2010

A high-flexion posterior-stabilized rotating-platform mobile-bearing prosthesis was designed in a... more A high-flexion posterior-stabilized rotating-platform mobile-bearing prosthesis was designed in an attempt to improve the range of motion after total knee arthroplasty without compromising the theoretical advantages of the posterior-stabilized rotating-platform mobile-bearing system. The aim of this study was to compare the outcomes of standard and high-flexion posterior-stabilized rotating-platform mobile-bearing total knee arthroplasties. One hundred and seventy knees were randomly allocated to receive either a standard (n = 85) or a high-flexion (n = 85) posterior-stabilized rotating-platform mobile-bearing prosthesis and were followed prospectively for a minimum of two years. Ranges of motion, functional outcomes determined with use of standard scoring systems, and radiographic measurements were assessed. In addition, patients' abilities to perform activities requiring deep knee flexion and patient satisfaction were evaluated with use of questionnaires. The average postopera...

Research paper thumbnail of Preservation of the posterior cruciate ligament is not helpful in highly conforming mobile-bearing total knee arthroplasty: a randomized controlled study

Knee Surgery, Sports Traumatology, Arthroscopy, 2012

Purpose The purpose of this study is to investigate whether the preservation of the posterior cru... more Purpose The purpose of this study is to investigate whether the preservation of the posterior cruciate ligament (PCL) can be helpful for improving kinematics and clinical outcome in highly conforming mobile-bearing total knee arthroplasty (TKA). Methods Ninety osteoarthritic knees were randomly allocated to either the PCL-preserving group or the PCLsacrificing group. Passive kinematics was recorded with a navigation system immediately after implantation. Three parameters (anterior/posterior translation, varus/valgus rotation, and internal/external rotation) were analysed from 0°to 120°flexion. Results The PCL-preserving group (42 knees) had more varus rotation over 90°flexion (p \ 0.05) and more anterior translation of the femur in all ranges of flexion (p \ 0.05) than those in the PCL-sacrificing group (44 knees). There was no difference in the internal/external rotation (p [ 0.05). The range of motion, functional scores, and radiographic results did not significantly differ between the two groups at the final follow-up. Three knees in the PCL-preserving group were revised: two presented with instability caused by traumatic attenuation of the PCL and one with subluxation of the insert due to a tight PCL. Conclusion The preservation of the PCL was not helpful for improving kinematics and clinical outcome in highly conforming mobile-bearing TKA. Level of evidence II.

Research paper thumbnail of Painful Patellar Clunk or Crepitation of Contemporary Knee Prostheses

Clinical Orthopaedics & Related Research, 2012

Background Painful patellar clunk or crepitation (PCC) is a resurgent complication of contemporar... more Background Painful patellar clunk or crepitation (PCC) is a resurgent complication of contemporary posterior-stabilized TKA. The incidence, time to presentation, causes, and treatment of PCC still remain controversial. Questions/purposes We therefore (1) compared the incidence of PCC with five contemporary TKA designs, (2) evaluated the time to presentation, (3) identified possible etiologies, and (4) determined recurrence rate and change in knee functional scores after treatment for PCC. Methods We reviewed 580 patients who had 826 posteriorstabilized TKAs involving five different designs. The incidences of PCC were compared among the prostheses. The knees were divided into two groups depending on the development of PCC, and possible etiologic factors of PCC, including prosthesis design and surgical or radiographic variables, were compared between groups. We investigated the onset time of PCC and evaluated treatment results by knee outcome scores. Minimum followup was 2.0 years (mean, 3.9 years; range, 2.0-9.8 years). Results The PCC incidence was higher in the Press-Fit Condylar 1 Sigma 1 Rotating Platform/Rotating Platform-Flex Knee System (11 of 113 knees, 9.7%) than in the others (seven of 713 knees, 1.0%). Increased risk of PCC was associated with using a specific prosthesis and patellar retention. PCC occurred in all cases within a year after TKA (mean, 7.4 months). Arthroscopic treatment (16 knees) and patellar replacement (two knees) improved knee scores, with no recurrence observed over an average followup of 29 months. Conclusions Prosthesis design and patellar retention were associated with PCC. Surgery resolved the PCC. Level of Evidence Level III, therapeutic study. See Instructions to Authors for a complete description of levels of evidence.

Research paper thumbnail of Plain Radiograph Fails to Reflect the Alignment and Advantages of Navigation in Total Knee Arthroplasty

The Journal of Arthroplasty, 2011

The study purposed to determine if a navigation in total knee arthroplasty (TKA) leads to accurat... more The study purposed to determine if a navigation in total knee arthroplasty (TKA) leads to accurate limb alignment and component position than the conventional technique as measured by full length standing radiographs and to evaluate the correlation between navigation and radiographic measurements. A total of 160 knees underwent navigation (n = 80) or conventional (n = 80) TKAs. The frontal femoral alignment was more accurate in navigation TKAs, whereas mechanical axis and frontal tibial alignment were similar in both techniques. Although the intraoperative navigation alignment showed no outliers, postoperative radiographic measure resulted as much as 20% of outliers, and there was no correlation between the two measurements. This lack of correlation and inherent limitations in measuring TKA alignment may bring to question if plain radiograph are useful to determine if alignment achieved by navigation is accurate.