header advert
Results 1 - 9 of 9
Results per page:
Applied filters
General Orthopaedics

Include Proceedings
Dates
Year From

Year To
Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_1 | Pages 38 - 38
1 Feb 2020
Kawamoto T Iida S Sakashita K
Full Access

Background

Total knee arthroplasty (TKA) was primarily considered a successful procedure, several new knee implants were introduced in recent years that seek to obtain improved stability and higher flexion. One of the implant, Vanguard XPTM BiCruciate retaining (BCR), Zinmmer-Biomet, USA recreates a specific kinematic model through the principle of normal joint.

Patients and Method

An unselected consecutive series of sixty-two patients undergoing primary TKA using the cemented total knee system between August 2016 and April 2018 were studied. Twenty-seven knees was operated using Vanguard XP, subsequently thirty-five knees were received a TKA using cruciate retaining cemented total knee system FINETMCR, Nakashimamedical, Japan.

Postoperatively standing AP hip-to-ankle radiographs were obtained, from which the lower extremity mechanical axis, component angle were measured. The alignment goals were a neutral mechanical axis defined as a hip-to-ankle angle of 0°with the femoral and tibial components aligned perpendicular to the mechanical axis. The total operating time were quantified utilising an operating room database. The total operating time between TKAs performed with Vanguard XP BCR and those performed with FINE CR was compared in each group. All patients postoperatively was evaluated of clinical results the Japan Orthopedics Association(JOA) Knee scores. We evaluated femoral component posterior offset (PFCO) in both of two group. The maximal protrusion of the posterior condyle, posteriorly to the extension line parallel to the tibial shaft from the edge of the posterior tibial component was measured on true lateral radiographs.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_4 | Pages 53 - 53
1 Feb 2017
Kawamoto T Iida S Suzuki C
Full Access

Background

Variability in component alignment continues to be a major in total knee arthroplasty(TKA). In the long term, coronal plane malalignment has been associated with an increased risk of loosening, insatability, and wear. Recently portable navigation system(PNS) in TKA have been introduced. The goal of PNS are to improve the accuracy of post operative alignment and eliminate outlier cases. The aim of this study is to evaluate clinical results and quantify the coronal plane alignment between a group of patients who underwent TKA using PNS versus CT-free large-console navigation system.

Patients and Method

An unselected consecutive series of ninety-four patients undergoing primary TKA using the cruciate retaining cemented total knee system between April 2012 and August 2015 were studied. Patients were included only if they were deemed to be candidates for a Cruciate retaining TKA. Patients were excluded if they had a flexion contracture greater than 40°, or severe valgus or varus deformity. Forty eight knees was operated a TKA with CT-free large-console navigation system(The OrthoPilot system; Aesculap, Tuttlingen, Germany). Subsequently forty six knees was received a TKA using portable navigation system (KneeAlign2TM). Postoperatively standing AP hip-to-ankle radiographs were obtained, from which the lower extremity mechanical axis, component angle were measured. The alignment goals were a neutral mechanical axis defined as a hip-to-ankle angle of 0°with the femoral and tibial components aligned perpendicular to the mechanical axis. The total operating time were quantified utilising an operating room database. The total operating time between TKAs performed with CT-free navigation system and those performed with portable navigation system was compared in each group. All patients postoperatively was evaluated of clinical results the Japan Orthopedics Association(JOA) Knee scores.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 96 - 96
1 Jan 2016
Kawamoto T Iida S
Full Access

Background

Variability in component alignment continues to be a major in total knee arthroplasty(TKA). In the long term, coronal plane malalignment has been associated with an increased risk of loosening, insatability, and wear. Recently, patient specific guide in total knee arthroplasty have been introduced, in which preoperative 3-dementional imaging is used to manufacture disposable cutting guide specific to a patient's anatomy. The goals of patient specific guide are to improve the accuracy of post operative alignment and eliminate outlier cases. The aim of this study is to evaluate clinical results and quantify the coronal plane alignment between a group of patients who underwent TKA using patient specific guide versus standard instrumentation.

Patients and Method: An unselected consecutive series of seventy patients undergoing primary TKA using the same cruciate retaining cemented total knee system (VanuardTM, Biomet, Inc, warsaw, Indiana USA) between April 2010 and September 2013 were studied. Patients were included only if they were deemed to be candidates for a

Cruciate retaining TKA. Patients were excluded if they had a flexion contracture greater than 40°, or severe valgus or varus deformity. Forty-nine knees was operated a TKA with standard instrumentation method. Subsequently twenty-one knees was received a TKA using CT-based patient specific guide(SignatureTM). Postoperatively standing AP hip-to-ankle radiographs were obtained, from which the lower extremity mechanical axis, component angle were measured. The alignment goals were a neutral mechanical axis defined as a hip-to-ankle angle of 0°with the femoral and tibial components aligned perpendicular to the mechanical axis. The total operating time were quantified utilising an operating room database. The total operating time between TKAs performed with standard instrumentation and those performed with patient specific guides was compared in each group. All patients postoperatively was evaluated of clinical results the Japan Orthopedics Association(JOA) Knee scores. Postoperative blood loss volume and postoperative concentrations of D-dimer were also measured.

Results

The mechanical axis angle in patient specific guide group was 1.8°, while the standard instrumentation group was 3.4°and there was no statistical significance. The number of outliers for mechanical axis angle was virtually identical between patient specific guide group 29.0% and the standard group 38.8%. The components angle between the two groups did not achieve statistical significance. The operative time in patient specific guide was 117.4 minutes and significantly less compared to the time of standard group 130.4 minutes. The JOA Knee score of standard instrumentation group was 80.8 points, and the score of patient specific guides group was 85.7 points. There was no statistical significance between the two groups on the clinical score. The blood loss volume of between the two group was no different substantially. The postoperative concentrations of D-dimer of patient specific guide group was 5.3(μg/ml), more less significantly than standard group 9.2 (μg/ml).


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_3 | Pages 44 - 44
1 Jan 2016
Miyamoto S Iida S Suzuki C Kishida S Nakamura J Shinada Y Hgiwara S Omae T
Full Access

Introduction

The cement mantle thickness for cemented stem during total hip arthroplasty (THA) is different between the complete cement mantle technique and the line-to-line technique. In the line-to-line technique, the size of the rasp is same as that of the stem. We performed THA in321 hipsof 289 patientsusing a new designed triple-tapered polished cemented stem. We investigated the short-term result of these 321 hips clinically and radiographically.

Materials and Methods

From February 2002 to December 2012, 321 THAs were performed in 289 patients with the use oftriple-tapered polished cemented stem (Trilliance). Of these, 306 hips in 274 patients who were followed over 6 months, were evaluated. All THAs were undergone with direct anterior approach in supine position. The third generation cementing technique was standardized. The mean age at surgery was 65.3 years and the mean follow-up period was 24.6 months. Clinical results were evaluated by Japanese Orthopaedic Association (JOA) hip score. Intra-postoperative complications were investigated. Radiographic examinations were performed to investigate the findings of stem loosening, stress shielding, radiolucent line, osteolysis, stem subsidence, stem alignmentand cementing grade on plain radiograph.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 41 - 41
1 Jan 2016
Suzuki C Iida S
Full Access

Introduction

Dislocation is one of severe complications after total hip arthroplasty (THA). Direct anterior approach (DAA) is useful for muscle preservation. Therefore, it might be also effective to reduce dislocation. The purpose of this study is to investigate the ratio and factors of dislocations after THA with DAA.

Materials & methods

Nine hundred fifity two primary THAs with DAA are examined. Mean age at operation was 64.9 yrs. 838 joints are in women and 114 (joints) in men. All THAs were performed under general anesthesia in supine position.

We reviewed the ratio, onset and frequency of dislocations, build of the patients, preoperative Japanese Orthopaedic Association (JOA) Hip scores, implant setting angles, pelvic tilt angles and diameter of inner heads.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 548 - 548
1 Dec 2013
Tamaki T Nimura A Oinuma K Shiratsuchi H Iida S Akita K
Full Access

Background:

In anterior approaches for total hip arthroplasty (THA), the femoral part of the procedure requires the release of the capsule from the greater trochanter. However, it is unknown whether any other tendons of the short external rotator muscles are also damaged during capsular release procedures. The aim of this cadaveric study was to identify the bony landmarks on the greater trochanter, which indicate the individual short external rotator muscle insertions.

Methods:

Forty-four hip regions from 28 embalmed cadavers were dissected. At first, micro-computed tomography (micro-CT) images were obtained to identify bony impressions on the greater trochanter. Then, the soft tissues around the greater trochanter were removed and their insertions were identified to assess correlation with micro-CT images.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 345 - 345
1 Mar 2013
Suzuki C Iida S
Full Access

Introduction

Accurate implantation is important for total hip arthroplasty to achieve a maximized, stable range of motion and to reduce the risk of dislocation. We had estimated total cup and stem anteversion(AV) visually during operations without navigation system. The purpose of this study is to assess the correlation between total AV estimated visually during operation and total AV evaluated with CT and X-ray postoperatively.

Materials & Methods

We investigated 145 primary total hip arthroplasties performed with direct anterior approach in supine position. 17 hips were in men and 128 in women. The mean age at operation was 65.6 years. During operations “intraoperative total AV” was defined as an angle from neutral hip position to internal rotated position at a concentric circle of acetabular rim and the equator of femoral head. We also measured cup inclination with X-ray and cup anteversion and stem anteversion with computed tomography after THA. “Radiographic total AV” was defined as the sum of cup and stem anteversion measured with CT. Correlation between “intraoperative total AV” and “Radiographic total AV” was evaluated statistically.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 327 - 327
1 Mar 2013
Shigemura T Kishida S Iida S Oinuma K Nakamura J Harada Y
Full Access

Objectives

The purpose of the present study was to describe the long-term results of THA for ONFH in patients with SLE.

Methods

From 1994–2001, 18 cementless THAs (14 SLE patients) were included in the present study. Four hips (3 patients) were lost to follow-up. The remaining 14 hips (11 patients) were available for evaluation. The mean follow-up period was 13.1(range, 10.0–16.4) years. The follow-up rate was 77.8%. The mean age at the time of surgery was 35.2 (range, 27.4–51.0) years.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XL | Pages 187 - 187
1 Sep 2012
Takazawa M Iida S Suzuki C
Full Access

Background

Between 1999 and August 2005, we performed Direct Lateral Approach (DLA) in lateral decubitus position as the main approach for primary total hip arthroplasty (THA). After August 2005, we introduced Direct Anterior Approach(DAA) in supine position. Intraoperative target orientation in primary THA was planned in 40–45°cup abduction, 10–20°cup anteversion, and 10–20° stem anteversion. Precice implant positioning has been considered to be very important for postoperative function and stability. The purpose of this study was to compare the DLA and DAA for implant positioning accuracy.

Methods

From 1999 to July 2009, we performed 566 primary THAs(78 male, 488 female). The subjects were divided into two groups of 224 DLA and 342 DAA (72 in early stage and 270 in late stage) The difference of the mean age at surgery and preoperative diagnosis among the groups were not significant. We planned to set the cup anteversion at 20°in DAA early stage and 12.5°in late stage DAA due to the development of postoperative dislocation in several cases with early stage DAA. We measured the cup and stem alignment postoperatively using radiography and computed tomography, and measured the combined anteversion angle by Widmer. Statistical analysis was done using the Bartlett Statistical Test and F-test. The results were expressed as median and interquartile range, with an alpha level set at less than 0.05.