The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Andrew D Pearle - One of the best experts on this subject based on the ideXlab platform.
-
different optimal alignment but equivalent functional outcomes in medial and lateral robotic assisted unicompartmental knee arthroplasty
Journal of Bone and Joint Surgery-british Volume, 2017Co-Authors: J Van Der List, Harshvardhan Chawla, Andrew D PearleAbstract:INTRODUCTION Medial and lateral unicompartmental knee arthroplasty (UKA) are both reliable treatment options for isolated osteoarthritis. Postoperative lower leg alignment is known to play an important role on short-term functional outcomes, which is an important argument for the use of robotic-assisted surgery. Since several anatomical and kinematic differences exist between both compartments, it seems inaccurate to aim for similar postoperative lower leg alignment in medial and lateral UKA. Purpose of this study was (I) to compare outcomes between both procedures and (II) to assess the role of preoperative and postoperative alignment on short-term outcomes in both procedures. METHODS Patients who underwent robotic-assisted medial or lateral UKA were included if they completed functional outcomes questionnaires preoperatively and postoperatively (Western Ontario and McMaster Universities Arthritis score) and completed an Artificial Joint awareness questionnaire (Forgotten Joint Score) postoperatively (not used preoperatively). A total of 143 medial UKA and 36 lateral UKA patients were included and mean follow-up was 2.4-years (range: 2.0 – 5.0 year). Postoperative alignment was measured using hip-knee-ankle radiographs with a standardized method. Alignment was categorized in medial and lateral UKA as undercorrection (3° to 7° varus or valgus, respectively), neutral (−1° to 3° varus or valgus, respectively), or overcorrection (3° to 7° valgus or varus, respectively). Outcomes were compared using independent t-tests and Pearson correlation analysis was performed to assess a correlation between alignment and outcomes. RESULTS No preoperative differences in functional outcomes were seen between medial UKA (54.9 ±14.9) and lateral UKA (50.3 ±13.4, p =0.304). Postoperatively, equivalent outcomes were noted between medial and lateral UKA in overall function (89.8 ±11.7 vs. 90.2 ±12.4, respectively, p =0.855) and Joint awareness (71.2 ±24.5 vs. 70.9 ±28.2, respectively, p =0.956). Correlation analysis did not show a correlation between preoperative alignment and both functional outcomes and Joint awareness for both procedures (all p > 0.4, Figure 1). More undercorrection was correlated with better functional outcomes (−0.355, p = 0.039) and less Joint awareness (−0.540, p =0.005) in lateral UKA (Figure 2). In medial UKA, no correlation was noted between postoperative alignment and both functional outcomes ( p =0.104) and Joint awareness ( p =0.069, Figure 2). With neutral postoperative alignment, less Joint awareness was noted following medial UKA than lateral UKA (72.6 ±22.6 vs. 55.3 ±28.5, p =0.024). With undercorrection, however, significantly less Joint awareness (85.3 ±19.5 vs. 68.2 ±26.8, p =0.024) and better functional outcomes (96.0 ±5.4 vs. 88.5 ±11.6, p =0.001) were noted following lateral UKA than medial UKA (Figure 3). CONCLUSION At short-term follow-up, equivalent outcomes were noted between medial and lateral UKA but the optimal postoperative alignment differed between both procedures. Undercorrection (3° to 7° valgus) resulted in most optimal outcomes in lateral UKA, while this was with neutral alignment (−1° to 3° varus) in medial UKA. This study showed that postoperative alignment plays a role on short-term outcomes of UKA and suggests that precise control of postoperative alignment should be pursued, which is possible with computer navigation or robotic-assisted surgery in UKA. For any figures or tables, please contact authors directly (see Info & Metrics tab above).
-
Unicompartmental knee arthroplasty versus total knee arthroplasty: Which type of Artificial Joint do patients forget?
Knee Surgery Sports Traumatology Arthroscopy, 2015Co-Authors: Hendrik A. Zuiderbaan, Saker Khamaisy, Danyal H. Nawabi, Ran Thein, C. Ishmael, Sophia Paul, Jelle P Van Der List, Andrew D PearleAbstract:Purpose During recent years, there has been an intensive growth of interest in the patient’s perception of functional outcome. The Forgotten Joint Score (FJS) is a recently introduced score that measures Joint awareness of patients who have undergone knee arthroplasty and is less limited by ceiling effects. The aim of this study was to compare the FJS between patients who undergo medial unicompartmental knee arthroplasty (UKA) and patients who undergo total knee arthroplasty (TKA) 1 and 2 years post-operatively.
Benjamin S Hsiao - One of the best experts on this subject based on the ideXlab platform.
-
tuning the superstructure of ultrahigh molecular weight polyethylene low molecular weight polyethylene blend for Artificial Joint application
ACS Applied Materials & Interfaces, 2012Co-Authors: Chen Chen, Ganji Zhong, Jun Lei, Benjamin S HsiaoAbstract:An easy approach was reported to achieve high mechanical properties of ultrahigh-molecular-weight polyethylene (UHMWPE)-based polyethylene (PE) blend for Artificial Joint application without the sacrifice of the original excellent wear and fatigue behavior of UHMWPE. The PE blend with desirable fluidity was obtained by melt mixing UHMWPE and low molecular weight polyethylene (LMWPE), and then was processed by a modified injection molding technology-oscillatory shear injection molding (OSIM). Morphological observation of the OSIM PE blend showed LMWPE contained well-defined interlocking shish-kebab self-reinforced superstructure. Addition of a small amount of long chain polyethylene (2 wt %) to LMWPE greatly induced formation of rich shish-kebabs. The ultimate tensile strength considerably increased from 27.6 MPa for conventional compression molded UHMWPE up to 78.4 MPa for OSIM PE blend along the flow direction and up to 33.5 MPa in its transverse direction. The impact strength of OSIM PE blend was increased by 46% and 7% for OSIM PE blend in the direction parallel and vertical to the shear flow, respectively. Wear and fatigue resistance were comparable to conventional compression molded UHMWPE. The superb performance of the OSIM PE blend was originated from formation of rich interlocking shish-kebab superstructure while maintaining unique properties of UHMWPE. The present results suggested the OSIM PE blend has high potential for Artificial Joint application.
Hendrik A. Zuiderbaan - One of the best experts on this subject based on the ideXlab platform.
-
Unicompartmental knee arthroplasty versus total knee arthroplasty: Which type of Artificial Joint do patients forget?
Knee Surgery Sports Traumatology Arthroscopy, 2015Co-Authors: Hendrik A. Zuiderbaan, Saker Khamaisy, Danyal H. Nawabi, Ran Thein, C. Ishmael, Sophia Paul, Jelle P Van Der List, Andrew D PearleAbstract:Purpose During recent years, there has been an intensive growth of interest in the patient’s perception of functional outcome. The Forgotten Joint Score (FJS) is a recently introduced score that measures Joint awareness of patients who have undergone knee arthroplasty and is less limited by ceiling effects. The aim of this study was to compare the FJS between patients who undergo medial unicompartmental knee arthroplasty (UKA) and patients who undergo total knee arthroplasty (TKA) 1 and 2 years post-operatively.
Meng Tian - One of the best experts on this subject based on the ideXlab platform.
-
strontium doped calcium polyphosphate ultrahigh molecular weight polyethylene composites a new class of Artificial Joint components with enhanced biological efficacy to aseptic loosening
Materials Science and Engineering: C, 2016Co-Authors: Bingxue Huang, Meng TianAbstract:To enhance implant stability and prolong the service life of Artificial Joint component, a new approach was proposed to improve the wear resistance of Artificial Joint component and endow Artificial Joint component with the biological efficacy of resistance to aseptic loosening. Strontium calcium polyphosphate (SCPP) were interfused in ultrahigh molecular weight polyethylene (UHMWPE) by a combination of liquid nitrogen ball-milling and flat-panel curing process to prepare the SCPP/UHMWPE composites. The micro-structure, mechanical characterization, tribological characterization and bioactivities of various SCPP/UHMWPE composites were investigated. The results suggested that this method could statistically improve the wear resistance of UHMWPE resulting from a good SCPP particle dispersion. Moreover, it is also observed that the SCPP/UHMWPE composites-wear particles could promote the production of OPG by osteoblasts and decrease the production of RANKL by osteoblasts, and then increase the OPG/RANKL ratio. This indicated that the SCPP/UHMWPE composites had potential efficacy to prevent and treat aseptic loosening. Above all, the SCPP/UHMWPE composites with a suitable SCPP content would be the promising materials for fabricating Artificial Joint component with ability to resist aseptic loosening.
Chen Chen - One of the best experts on this subject based on the ideXlab platform.
-
tuning the superstructure of ultrahigh molecular weight polyethylene low molecular weight polyethylene blend for Artificial Joint application
ACS Applied Materials & Interfaces, 2012Co-Authors: Chen Chen, Ganji Zhong, Jun Lei, Benjamin S HsiaoAbstract:An easy approach was reported to achieve high mechanical properties of ultrahigh-molecular-weight polyethylene (UHMWPE)-based polyethylene (PE) blend for Artificial Joint application without the sacrifice of the original excellent wear and fatigue behavior of UHMWPE. The PE blend with desirable fluidity was obtained by melt mixing UHMWPE and low molecular weight polyethylene (LMWPE), and then was processed by a modified injection molding technology-oscillatory shear injection molding (OSIM). Morphological observation of the OSIM PE blend showed LMWPE contained well-defined interlocking shish-kebab self-reinforced superstructure. Addition of a small amount of long chain polyethylene (2 wt %) to LMWPE greatly induced formation of rich shish-kebabs. The ultimate tensile strength considerably increased from 27.6 MPa for conventional compression molded UHMWPE up to 78.4 MPa for OSIM PE blend along the flow direction and up to 33.5 MPa in its transverse direction. The impact strength of OSIM PE blend was increased by 46% and 7% for OSIM PE blend in the direction parallel and vertical to the shear flow, respectively. Wear and fatigue resistance were comparable to conventional compression molded UHMWPE. The superb performance of the OSIM PE blend was originated from formation of rich interlocking shish-kebab superstructure while maintaining unique properties of UHMWPE. The present results suggested the OSIM PE blend has high potential for Artificial Joint application.
