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.

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.

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.

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.

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.

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.

Reconstruction of 10mm segmental bone defects in rat by mesenchymal stem cell derived chondrogenic cells (MSC-DC)

Objective

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

Objective

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

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.

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.

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.

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.