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The Bone & Joint Journal
Vol. 103-B, Issue 3 | Pages 456 - 461
1 Mar 2021
Sasaki G Watanabe Y Yasui Y Nishizawa M Saka N Kawano H Miyamoto W

Aims

To clarify the effectiveness of the induced membrane technique (IMT) using beta-tricalcium phosphate (β-TCP) for reconstruction of segmental bone defects by evaluating clinical and radiological outcomes, and the effect of defect size and operated site on surgical outcomes.

Methods

A review of the medical records was conducted of consecutive 35 lower limbs (30 males and five females; median age 46 years (interquartile range (IQR) 40 to 61)) treated with IMT using β-TCP between 2014 and 2018. Lower Extremity Functional Score (LEFS) was examined preoperatively and at final follow-up to clarify patient-centered outcomes. Bone healing was assessed radiologically, and time from the second stage to bone healing was also evaluated. Patients were divided into ≥ 50 mm and < 50 mm defect groups and into femoral reconstruction, tibial reconstruction, and ankle arthrodesis groups.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_5 | Pages 138 - 138
1 Apr 2019
Watanabe Y Yamamoto S Isawa K Yamada N Hirota Y
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Background

Recently, a larger number of elderly individuals with osteoporosis has undergone total knee arthroplasty (TKA). Intuitively, such vulnerable bone condition should deteriorate post-TKA functional recovery compared to a non-osteoporotic condition, but this hypothesis has not been directly examined.

Methods

To address this issue, we analysed prognosis of patients who underwent TKA in Toranomon Hospital in Japan between April 2016 and March 2017 (27 of 40 cases, age 75.0±8.2 years old, BMI 24.5±3.1), and evaluated effects of osteoporosis on the changes in functions of the knees three/six/twelve months after the operation. The knee functions were quantified based on Knee Society Score (KSS), and the severity of the pre-operative osteoporosis was evaluated by T-score. We examined the relationships between these scores using multiple regression analyses with age, BMI, and sex as covariates. We excluded patients with rheumatoid arthritis.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_5 | Pages 92 - 92
1 Apr 2019
Watanabe Y Yamamoto S Isawa K Shiono H Yamada N Hirota Y
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Background

Acromegaly, which stems from high level of serum growth hormone secreted by a benign tumour in the anterior pituitary gland, is likely to cause severe peripheral joint pains due to hypertrophic changes in such joints. Recently, the life expectancy of such patients has been improved and more patients with acromegaly have undergone joint surgeries to mitigate joint pain and malfunctions. However, little is known about to what extent surgical procedures can improve the joint functions of acromegalic patients compared to non-acromegalic cases.

Methods

First, we qualitatively analysed prognosis of total hip arthroplasty (THA) of acromegalic patients by investigating 11 cases in which direct anterior approach (DAA) THAs were performed to 8 acromegalic patients in our hospital between 2012 and 2015.

Second, we quantitatively compared the functional prognosis of the 11 cases with that of 107 non-acromegalic cases. Technically, to control the difference in age, sex, height, and weight between the two patient groups, we first identified a model that could predict 3month-/6month-/12month-functional prognosis in the control cases. We estimated differences in functional outcomes between the two groups by calculating how accurately the control-case-based model could predict the prognosis of the acromegalic cases.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_11 | Pages 68 - 68
1 Jul 2014
Harada N Watanabe Y Abe S Sato K Iwai T Yamamoto I Yamada K Yamanaka K Sakai Y Kaneko T Matsushita T
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Introduction

Mesenchymal stem cells (MSCs) are identified by having the ability to differentiate into various tissues and typically used to generate bone tissue by a process of resembling intramembranous ossification, namely by direct osteoblastic differentiation. However, most bones develop by endochondral ossification, namely via remodeling of hypertrophic cartilaginous templates. To date, reconstruction of bone defects by endochondral ossification using mesenchymal stem cell-derived chondrocytes (MSC-DCs) have not been reported. The purpose of this study was to evaluate the effects of the transplantation of MSC-DCs on bone healing in segmental defects in rat femurs.

Methods

Segmental bone defects (5, 10, 15-millimeter) were produced in the mid-shaft of the femur of the Fisher 344 rats and stabilised with an external fixator. Bone marrow was aspirated from the rat's femur and tibia at 4 weeks before operation. MSCs were isolated and grown in culture and seeded on a Poly dl-lactic-co glycolic acid (PLGA) scaffold. Subsequently, the scaffold was cultured using chondrogenic inducing medium for 21 days. The characteristics of the PLGA scaffold are radiolucent and to be absorbed in about 4 months. The Treatment Group received MSC-DCs, seeded on a PLGA scaffold, locally at the site of the bone defect, and Control Group received scaffold only. The healing processes were monitored radiographically and studied biomechanically and histologically.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 19 - 19
1 Apr 2013
Harada N Watanabe Y Abe S Sato K Yamanaka K Sakai Y Kaneko T Matsushita T
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Purpose

The purpose of this study was to evaluate the effects of implantation of mesenchymal stem cell derived condrogenic cells (MSC-DC) on bone healing in segmental defects in rat femur.

Methods

Five-millimeter segmental bone defects were produced in the mid-shaft of the femur of Fisher 344 rats and stabilized with external fixator. The Treatment Group received MSC-DC, seeded on a PLGA scaffold, locally at the site of the bone defect, and Control Group received scaffold only. The healing processes were monitored radiographically (Softex), and studied radiographically (Micro-CT) and histologically.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 65 - 65
1 Apr 2013
Watanabe Y Takenaka N Kobayashi M Matsushita T
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Objective

To investigate the outcomes of patients following the chipping procedures as an alternative to bone grafting in treatment of non-unions after long bone fracture.

Patients

Sixteen patients with femoral or tibial non-union were included. The median follow-up was 24 months.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 83 - 83
1 Apr 2013
Sato K Watanabe Y Abe S Harada N Yamanaka K Sakai Y Kaneko T Matsushita T
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Introduction

what size of defect is optimal for creating an atrophic nonunion animal model has not been well defined. Our aim in this study was to establish a clinically relevant model of atrophic nonunion in rat femur by creation of a bone defect to research fracture healing and nonunion.

Materials and methods

We used 30 male Fischer 344 rats (aged 10–11 weeks), which were equally divided into six groups. The segmental bone defects to a single femur in each rat were performed by double transverse osteotomy, and different sized defects were created by group for each group (1 mm, 2 mm, 3 mm, 4 mm, 5 mm and 6 mm). The defects were measured and maintained strictly by using an original external fixator. The periosteum for each defect was stripped both proximally and distally. Thereafter, these models were evaluated by radiology and histology. Radiographs were taken at baseline and at intervals of two weeks over a period of 8 weeks. Atrophic nonunion was defined as a lack of continuity and atrophy of both defect ends radiologically and histologically at eight weeks.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 35 - 35
1 Apr 2013
Sato K Watanabe Y Abe S Harada N Yamanaka K Sakai Y Kaneko T Matsushita T
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Reconstruction of 10mm segmental bone defects in rat by mesenchymal stem cell derived chondrogenic cells (MSC-DC)

Background

Mesenchymal stem cell derived condrogenic cells (MSC-DC) have excellent potential for healing 5 mm bone defect in rat femur.

Purpose

To evaluate the effectiveness of MSC-DC on bone healing in 10 mm segmental bone defects in rat femur.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 30 - 30
1 Apr 2013
Watanabe Y Arai Y Takenaka N Kobayashi M Matsushita T
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Objective

To determine what factors affect fracture healing with low-intensity pulsed ultrasound (LIPUS) for delayed unions and nonunions.

Patients

A consecutive cohort of 101 delayed unions and 50 nonunions after long bone fractures treated with LIPUS between May 1998 and April 2007.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 98 - 98
1 Apr 2013
Watanabe Y
Full Access

Objective

To investigate the outcomes of patients following the chipping procedures as an alternative to bone grafting in treatment of femoral non-unions.

Design

Retrospective evaluation of prospectively collected data.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 75 - 76
1 Mar 2010
Watanabe Y Nakano T Sawaguchi T Fukui N Fujino K Matsushita T
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Objective: To study potential predictors of functional outcome six months after the injury in elderly patients who sustained a hip fracture and who had been able to go out alone.

Design: Prospective Multi-center Cohort Study

Setting: 14 Hospitals in Japan

Patients and Methods: A cohort was consisted of 387 patients with a mean age of 81 who had a hip fracture, between December 2004 and January 2006. Inclusion criteria were that patients were at least sixty-five years old and who had been able to go out independently. Level of activity of daily living, medical complications, residential environment and family structure at injury was interviewed from the patient, the relatives and a nursing caretaker and recorded. Advancement of mobility was also recorded during the hospital stay. Patients were contacted or interviewed again by the investigator at six months following injury to assess functional outcomes. Primary outcome of interest was changes in mobility to go out independently at six months after injury.

Results: 178 patients (46%) lost their independency to go out at six month following surgery. Logistic multivariant regression showed that age, cognitive function, hemiplegia and mobile ability at discharge were the independent predictable factors for losing independency of mobility. At hospital discharge, T-cane walk was accomplished in only 53% for looser group but 86% for maintain group.

Conclusions: We believe that it would be the key factor to improve the mobility of the healthy patient with hip fracture that we lead them to T-cane walk before hospital discharge.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 76 - 77
1 Mar 2010
Watanabe Y Arai Y Nishizawa Y Takenaka N Matsushita T
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Background: Low-intensity pulsed ultrasound (LIPUS) was shown to accelerate fracture healing with delayed unions and non-unions as well as fresh fractures.

Objective: To know the factors which affected clinical results of LIPUS treatment for delayed unions and non-unions.

Design: Prospective Cohort Study

Setting: University Hospital

Intervention: 192 delayed or non-unions of long bone or clavicle were treated by LIPUS from May 1998 to April 2007. Background factors (age and gender of patient, history of smoking, personality of each fracture, intervals from injury to application of LIPUS treatment) were prospectively investigated. All patients were followed up at the outpatient clinic and AP and lateral view of radiographs were taken usually every 4 weeks. Main outcome of this study was set as “bone union” and it was defined as cortical continuity in a minimum of three cortices on two views on radiographs and without pain at the fracture site on palpation.

Main Outcome Measurement: The overall success rate was 75%, and the success rate of subcutaneous bones were higher (tibia: 81%, radius and ulna: 80%)than that of deeper bone (femur: 64%, humerus 58%). Logistic multi-variant regression showed that the greatest gap size between the main bone fragments (p< 0.0001), instability of a fracture site (p< 0.0001), and the intervals between injury to the application of LIPUS (p< 0.05) were independent predictors for the success of LIPUS treatment for delayed and non-unions.

Conclusion: We believe that the greatest gap size of main fragments, instability of a fracture site, and the age of non-union are the factors that affected LIPUS clinical results.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 77 - 77
1 Mar 2010
Takenaka N Watanabe Y Nishizawa M Nishizawa Y Matsushita T
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Objective: The purpose of the present study was to assess whether clinicians are actually able to evaluate the mechanical status of lengthening callus from plain radiographs.

Materials and Methods: 36 rats were employed in this study. Their left femurs were lengthened by 6 mm as a bone lengthening model. Rats were euthanized at 4 8 12 and 16 weeks after lengthening. Both femora were X-rayed and then bone density parameters (bone mineral content, bone mineral density and bone area) of lengthening callus were measured using pQCT. Three-point bending test was performed to determine the mechanical strength of the both bones. We defined the ratio of the strength of lengthening side to control side as estimated strength recovery rate (%). Then 20 orthopaedic surgeons evaluated only the X-ray photographs and tried to estimate the relative mechanical strength (%) of the affected side compared to the control side.

Results: Between the recovery percentage of mechanical strength and bone mineral content, a positive simple correlation (R2=0.11, p< 0.05) was seen. No significant correlation was seen between the recovery percentage of mechanical strength estimated by orthopaedists and the mechanical strength measured by three-point bending test (qualified doctors: R2=0.0793 p=0.291 unqualified doctors: R2=0.0523 p=0.394).

Discussion and conclusion: It became obvious that to estimate the strength of lengthening callus from plain radiographs alone is quite difficult as compared with the studies of the simple fracture model that have been reported until now.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 428 - 428
1 Apr 2004
Ohtsuki Y Takai S Yoshino N Kobayashi M Watanabe Y
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Introduction: Soft tissue balancing remains the most subjective and most artistic of current techniques in total knee arthroplasty. The flexion gap is traditionally measured at approximately 45 degree of hip flexion and 90 degree of knee flexion on the operation table. Despite of aiming equal joint gaps or tensions in flexion and extension, influence of the thigh weight on the flexion gap has not been documented. Therefore, the purpose of this study was to examine the flexion gaps in the 90-90 degree flexed position and the traditional 45-90 degree flexed position of hip-knee joints.

Materials and methods: Thirty patients with osteoarthritic knee underwent total knee arthroplasty. After the PCL sacrifice, soft tissue releases, and bone cuts, the specially designed tenser which has two load cells was employed. 160N was applied to open the joint gaps in the traditional 45-90 degree flexed position and the 90-90 degree flexed position of hip-knee joints.

Results: The flexion gap in the 90-90 degree flexed position of hip-knee joints was 2.1±1.2mm wider than that in the traditional 45-90 degree flexed position of hip-knee joints. The flexion gap had significant difference between the two different hip flexion angles (p< 0.001).

Discussions: In the traditional 45-90 degree flexed position of hip-knee joints on the operation table, the flexion gap is approximately 45 degree to the gravitation and influenced by the thigh weight. To avoid the influence of the thigh weight and obtain equal joint gaps or tensions in flexion and extension, the flexion gap should be checked in the 90-90 degree flexed position of hip-knee joints.