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Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_15 | Pages 87 - 87
1 Nov 2018
Fujito T Tomita T Yamazaki T Tamaki M Ishibashi T Kono K Konda S Yoshikawa H Sugamoto K
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Our aim was to investigate whether it is possible to predict post-operative kinematics (Post-Ope) from intra-operative kinematics (Intra-Ope) after total knee arthroplasty. Our study were performed for 11 patients (14 knees) who underwent primary PS TKA using CT-based navigation system between Sept.2012 and Sept.2014. The mean subject age was 71.5 ± 5.5 years at the time of surgery. Intra-Ope was measured using the navigation system after implantation during passive full extension and flexion imposed by the surgeon. Under fluoroscopic surveillance, each patient was asked to perform sequential deep knee flexion under both non-weight bearing (NWB) and weight bearing (WB) conditions from full extension to maximum flexion. To estimate the spatial position and orientation, we used a 2- to 3- dimensional (2D3D) registration technique. Intra-Ope and Post-Ope had a common coordinate axis for bones. Evaluations were range of motion (ROM), external rotation angles (ER). The level of statistical significant difference was set at 0.05. Mean ROM in Intra-Ope(130°± 7.9°) was statistically larger than both NWB(121.1°±10.5°) and WB(124.0°±14.7°). No Statistically significant difference was found in the mean ER from 10° to 120° among Intra-Ope (11.2°± 8.5°) and NWB(7.1°±6.0°) and WB(5.3°±3.2°). It is suggested that we could predict Post-Ope from Intra-Ope by considering the increase of the range of motion due to the muscle relaxation condition and the amount of change in the ER.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_16 | Pages 51 - 51
1 Nov 2018
Ishibashi T Tomita T Yamazaki T Fujito T Kono K Konda S Tamaki M Yoshikawa H Sugamoto K
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Bi-cruciate stabilized (BCS) TKA is the prosthesis that aims to substitute bi-cruciate ligament with post-cam engagement. We estimated to describe the in vivo kinematics during deep knee bending in BCS and Cruciate retaining (CR) TKA with the same articular geometry. We analyzed 26 knees who agreed to the current investigation under institutional review board approval. 17 knees were implanted with BCS (Journey ∥BCS, Smith & Nephew. Memphis, US) and 9 knees with CR (Journey∥CR). Each patient was asked to perform deep knee bending under weight-bearing condition. To estimate the spatial position and orientation of the TKA, 2D/3D registration technique with single fluoroscopy was used. We evaluated anteroposterior (AP) translation of the nearest point from femoral component to tibial axial plane for medial and lateral sides, femoral external rotation relative to tibial component and post-cam engagement in BCS. Measurement results were analyzed using Wilcoxon test. Values of P<0.05 were considered statistically significant. Medial AP translation indicated 11.7±5.1% posterior movement in BCS and 4.0±6.6% anterior movement in CR from minimum flexion to 130°. Lateral AP translation indicated 28.9±11.4% posterior movement in BCS and 18.3±6.2% posterior movement in CR from minimum flexion to 130°. Femoral external rotation were observed in both group and the amount of rotation were 5.2°±4.5° in BCS and 8.2°±4.0° in CR. Anterior post-cam engagement was not observed in all cases (76.5%). But medial AP translation in BCS was anteriorly in shallow flexion angles compared to CR. It suggested that anterior post-cam engagement couldn't work in valid.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_16 | Pages 52 - 52
1 Nov 2018
Kono K Tomita T Yamazaki T Ishibashi T Fujito T Konda S Futai K Tanaka S Sugamoto K
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There are few studies that have compared between continuous flexion activities and extension activities of normal knees. The purpose of this study is to compare in vivo kinematic comparison of normal knees between flexion activities and extension activities. Total of 8 normal male knees were investigated. We evaluated in vivo three-dimensional kinematics using 2D/3D registration technique. We compared femoral rotation angle relative to tibia, anterior/posterior (AP) translation of medial femoral sulcus (medial side) and lateral femoral epicondyle (lateral side) onto tibial plane perpendicular to tibial functional axis between flexion activities (F groups) and extension activities (E groups). Femoral external rotation was observed with the knee bending during both groups. The external rotation angle of F group was larger than that of E group significantly from 20 to 30 degrees with flexion (p < 0.05). Regarding medial side, anterior translation was observed up to 40 degrees in F group. From 40 to 140 degrees, posterior translation was observed. In E group, anterior translation was observed from 140 to 40 degrees with extension. From 40 degrees, posterior translation was observed. From 30 to 40 degrees, F group located anterior than E group (p < 0.05). Regarding lateral side, posterior translation was observed with flexion in F group. On the other hand, anterior translation was observed with extension in E group. Regarding AP location with flexion angle, there was no significant difference between two groups. In conclusion, there were different kinematics between flexion activities and extension activities.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_3 | Pages 87 - 87
1 Apr 2018
Fujito T Tomita T Yamazaki T Futai K Ishibashi T Yoshikawa H Sugamoto K
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Purpose

This study was to investigate the effect of posterior tibial slope (PTS) on the kinematics in the cruciate-retaining total knee arthroplasty (CR-TKA) using 2- to 3- dimensional registration technique.

Material & Methods

A total of 75 knees in 58 patients were recruited and categorized into the following two groups according to PTS. Group A was categorized PTS under 7degrees (n = 33) and group B was categorized PTS over 7 degrees (n = 42). The average age of group A and group B at the time of fluoroscopic surveillance date was 73.5 ± 7.4 years and 74.3 ± 4.5 years, respectively and the average follow-up period from operation date to fluoroscopic surveillance date was 13.8 ± 9.3 months and 16.7 ± 8.6 months, respectively. In vivo kinematics during sequential deep knee bending under weight-bearing condition were evaluated using fluoroscopic image analysis and 2- to 3- dimensional registration technique. Range of motion (ROM), axial rotation, anteroposterior (AP) translations of medial and lateral nearest points of the femoral component relative to the tibial component were measured and compared between the two groups. The nearest points were determined by calculating the closest distance between the surfaces of femoral component model and the axial plane of coordinate system of the tibial component. We defined external rotation and anterior translation as positive. P values under 0.05 was defined as statistically significant.


The Journal of Bone & Joint Surgery British Volume
Vol. 76-B, Issue 4 | Pages 555 - 558
1 Jul 1994
Yamamoto H Muneta T Ishibashi T Furuya K

We reviewed 19 children with 24 congenital club feet at a mean of 11 years after one-stage posteromedial release at the age of five years or older (mean 6.8 years). Thirteen feet had undergone previous surgery. Nineteen feet were functionally excellent or good, three were fair and two had required subtalar arthrodesis. Radiographs showed good alignment of the tarsal bones, although mild adduction or varus deformity remained in several feet. Deformities of the bones were more common in feet which had had previous surgery.