Eccentric reductions may become concentric through femoral head ‘docking’ (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI. We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.Aims
Methods
This study aimed, through bioinformatics analysis, to identify the potential diagnostic markers of osteoarthritis, and analyze the role of immune infiltration in synovial tissue. The gene expression profiles were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) were identified by R software. Functional enrichment analyses were performed and protein-protein interaction networks (PPI) were constructed. Then the hub genes were screened. Biomarkers with high value for the diagnosis of early osteoarthritis (OA) were validated by GEO datasets. Finally, the CIBERSORT algorithm was used to evaluate the immune infiltration between early-stage OA and end-stage OA, and the correlation between the diagnostic marker and infiltrating immune cells was analyzed.Aims
Methods
Osteoarthritis (OA) is characterized by persistent destruction of articular cartilage. It has been found that microRNAs (miRNAs) are closely related to the occurrence and development of OA. The purpose of the present study was to investigate the mechanism of miR-486 in the development and progression of OA. The expression levels of miR-486 in cartilage were determined by quantitative real-time polymerase chain reaction (qRT-PCR). The expression of collagen, type II, alpha 1 (COL2A1), aggrecan (ACAN), matrix metalloproteinase (MMP)-13, and a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS4) in SW1353 cells at both messenger RNA (mRNA) and protein levels was determined by qRT-PCR, western blot, and enzyme-linked immunosorbent assay (ELISA). Double luciferase reporter gene assay, qRT-PCR, and western blot assay were used to determine whether silencing information regulator 6 (SIRT6) was involved in miR-486 induction of chondrocyte-like cells to a more catabolic phenotype.Aims
Methods
The proportion of arthroplasties performed in the ambulatory setting has increased considerably. However, there are concerns whether same-day discharge may increase the risk of complications. The aim of this study was to compare 90-day outcomes between inpatient arthroplasties and outpatient arthroplasties performed at an ambulatory surgery centre (ASC), and determine whether there is a learning curve associated with performing athroplasties in an ASC. Among a single-surgeon cohort of 970 patients who underwent arthroplasty at an ASC, 854 (88.0%) were matched one-to-one with inpatients based on age, sex, American Society of Anesthesiologists (ASA) grade, BMI, and procedure (105 could not be adequately matched and 11 lacked 90-day follow-up). The cohort included 281 total hip arthroplasties (THAs) (32.9%), 267 unicompartmental knee arthroplasties (31.3%), 242 primary total knee arthroplasties (TKAs) (28.3%), 60 hip resurfacings (7.0%), two revision THAs (0.3%), and two revision TKAs (0.3%). Outcomes included readmissions, reoperations, visits to the emergency department, unplanned clinic visits, and complications.Aims
Methods
Recent total knee arthroplasty (TKA) designs have featured more anatomical morphologies and shorter tibial keels. However, several reports have raised concerns about the impact of these modifications on implant longevity. The aim of this study was to report the early performance of a modern, cemented TKA design. All patients who received a primary, cemented TKA between 2012 and 2017 with a minimum two-year follow-up were included. The implant investigated features an asymmetrical tibial baseplate and shortened keel. Patient demographic details, Knee Society Scores (KSS), component alignment, and the presence of radiolucent lines at final follow-up were recorded. Kaplan-Meier analyses were performed to estimate survivorship.Aims
Methods
The aim of this study was to compare ten-year longitudinal healthcare costs and revision rates for patients undergoing unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). The Humana database was used to compare 2,383 patients undergoing UKA between 2007 and 2009, who were matched 1:1 from a cohort of 63,036 patients undergoing primary TKA based on age, sex, and Elixhauser Comorbidity Index. Medical and surgical complications were tracked longitudinally for one year following surgery. Rates of revision surgery and cumulative mean healthcare costs were recorded for this period of time and compared between the cohorts.Aims
Methods
The efficacy and safety of intrawound vancomycin for preventing surgical site infection in primary hip and knee arthroplasty is uncertain. A systematic review of the literature was conducted, indexed from inception to March 2020 in PubMed, Web of Science, Cochrane Library, Embase, and Google Scholar databases. All studies evaluating the efficacy and/or safety of intrawound vancomycin in patients who underwent primary hip and knee arthroplasty were included. Incidence of periprosthetic joint infection (PJI), superficial infection, aseptic wound complications, acute kidney injury, anaphylactic reaction, and ototoxicity were meta-analyzed. Results were reported as odds ratios (ORs) and 95% confidence intervals (CIs). The quality of included studies was assessed using the risk of bias in non-randomized studies of interventions (ROBINS-I) assessment tool.Aims
Methods
Recent total knee arthroplasty (TKA) designs have featured more anatomic morphologies and shorter tibial keels. However, several reports have raised concerns regarding the impact of these modifications on implant longevity. This study's purpose is to report the early performance of a modern, cemented TKA design. All patients who received a primary, cemented TKA from 2012 to 2017 with a minimum two-year follow-up were included. This implant features an asymmetric tibial baseplate and a shortened keel. Patient demographics, Knee Society Scores (KSS), and component alignment were recorded, and Kaplan-Meier survivorship analyses were performed.Introduction
Methods
The proportion of arthroplasties performed in the ambulatory setting has increased substantially. However, concerns remain regarding whether same-day discharge may increase the risk of complications. The purpose of this study was to compare 90-day outcomes between inpatients and patients having surgery at an ambulatory surgery center (ASC). Among a single-surgeon cohort of 721 patients who underwent arthroplasty at a free-standing ASC, 611 (84.7%) were matched one-to-one to inpatients based on age, gender, American Society of Anesthesiologists (ASA) score, and Body Mass Index (110 patients could not be adequately matched). The cohort included 208 total hip arthroplasties (34.0%), 196 total knee arthroplasties (32.1%), 178 unicompartmental knee arthroplasties (29.1%), 25 hip resurfacings (4.1%), two revision hip arthroplasties (0.3%) and two revision knee arthroplasties (0.3%). Post-operative outcomes including readmissions, reoperations, unplanned clinic visits, emergency department visits, and complications were compared. Complications were classified as either major (i.e. death, periprosthetic joint infection, pulmonary embolism) or as minor (i.e. delayed wound healing, rashes, urinary retention).Introduction
Methods
The proportion of arthroplasties performed in the ambulatory setting has increased substantially. However, concerns remain regarding whether same-day discharge may increase the risk of complications. The purpose of this study was to compare 90-day outcomes between inpatients and patients having surgery at an ambulatory surgery center (ASC). Among a single-surgeon cohort of 721 patients who underwent arthroplasty at a free-standing ASC, 611 (84.7%) were matched one-to-one to inpatients based on age, gender, American Society of Anesthesiologists (ASA) score, and Body Mass Index (110 patients could not be adequately matched). The cohort included 208 total hip arthroplasties (34.0%), 196 total knee arthroplasties (32.1%), 178 unicompartmental knee arthroplasties (29.1%), 25 hip resurfacings (4.1%), two revision hip arthroplasties (0.3%) and two revision knee arthroplasties (0.3%). Post-operative outcomes including readmissions, reoperations, unplanned clinic visits, emergency department visits, and complications were compared. Complications were classified as either major (i.e. death, periprosthetic joint infection, pulmonary embolism) or as minor (i.e. delayed wound healing, rashes, urinary retention).Introduction
Methods
Wound complications following revision total hip arthroplasty (THA) are associated with an increased risk of superficial and deep infections. Closed incision negative-pressure therapy (ciNPT) has been reported to decrease this risk. This study's purpose was to assess if ciNPT decreases the rate of wound complications following revision THA versus a conventional, silver-impregnated dressing. This was a single center, randomized controlled trial of patients undergoing both septic and aseptic revision THA. Patients received either ciNPT or a silver-impregnated dressing (control) for 7 days. Wound complications within 90 days of the procedure were recorded, including: surgical site infection (SSI), periprosthetic joint infection (PJI), prolonged drainage greater than 5 days, erythema requiring antibiotics, and hematoma formation. An Introduction
Methods
In patients with a “dry” aspiration during the investigation of prosthetic joint infection (PJI), saline lavage is commonly used to obtain a sample for analysis. The aim of this study was to investigate prospectively the impact of saline lavage on synovial fluid analysis in revision arthroplasty. Patients undergoing revision hip (THA) or knee arthroplasty (TKA) for any septic or aseptic indication were enrolled. Intraoperatively, prior to arthrotomy, the maximum amount of fluid possible was aspirated to simulate a dry tap (pre-lavage) followed by the injection with 20 ml of normal saline and re-aspiration (post-lavage). Pre- and post-lavage synovial white blood cell (WBC) count, percent polymorphonuclear cells (%PMN), and cultures were compared.Aims
Methods
The aim of this study was to determine if a three-month course of microorganism-directed oral antibiotics reduces the rate of failure due to further infection following two-stage revision for chronic prosthetic joint infection (PJI) of the hip and knee. A total of 185 patients undergoing a two-stage revision in seven different centres were prospectively enrolled. Of these patients, 93 were randomized to receive microorganism-directed oral antibiotics for three months following reimplantation; 88 were randomized to receive no antibiotics, and four were withdrawn before randomization. Of the 181 randomized patients, 28 were lost to follow-up, six died before two years follow-up, and five with culture negative infections were excluded. The remaining 142 patients were followed for a mean of 3.3 years (2.0 to 7.6) with failure due to a further infection as the primary endpoint. Patients who were treated with antibiotics were also assessed for their adherence to the medication regime and for side effects to antibiotics.Aims
Methods
X-linked hypophosphataemic rickets (XLHR) is a disease of impaired bone mineralization characterized by hypophosphataemia caused by renal phosphate wasting. The main clinical manifestations of the disorder are O-shaped legs, X-shaped legs, delayed growth, and bone pain. XLHR is the most common inheritable form of rickets, with an incidence of 1/20 000 in humans. It accounts for approximately 80% of familial cases of hypophosphataemia and serves as the prototype of defective tubular phosphate (PO43+) transport, due to extra renal defects resulting in unregulated The genome DNA samples of all members in the pedigree were extracted from whole blood. We sequenced all exons of the Objectives
Methods
The present study investigated the five-year interval changes in pseudotumours and measured serum metal ions at long-term follow-up of a previous report of 28 mm diameter metal-on-metal (MoM) total hip arthroplasty (THA). A total of 72 patients (mean age 46.6 years (37 to 55); 43 men, 29 women; 91 hips) who underwent cementless primary MoM THA with a 28 mm modular head were included. The mean follow-up duration was 20.3 years (18 to 24). All patients had CT scans at a mean 15.1 years (13 to 19) after the index operation and subsequent follow-up at a mean of 20.2 years (18 to 24). Pseudotumour volume, type of mass, and new-onset pseudotumours were evaluated using CT scanning. Clinical outcomes were assessed by Harris Hip Score (HHS) and the presence of groin pain. Serum metal ion (cobalt (Co) and chromium (Cr)) levels were measured at the latest follow-up.Aims
Patients and Methods
The results of ceramic-on-ceramic (CoC) bearing surfaces in primary total hip arthroplasty (THA) were well known. However, it was not known in revision THA. The purpose of this study is to report the results of revision THA with ceramic articulation. 112 revision THAs with ceramic articulation were evaluated. The mean age at the time of surgery was 58.3 years (28 to 97). The mean duration of the follow-up periods was 6.4 years (2 to 11.8 years).Purpose
Materials and Methods
In vivo comparative gap measurements were performed in 3 different patella positions (reduced, subluxated and everted) using offset-type-force-controlled-spreader-system. Prospectively, 50 knees were operated by TKA using a navigation-assisted gap balancing technique. The offset-type-force-controlled-spreader-system was used for gap measurements. This commercially-available instrument allows controllable tension in patella reduced position. The mediolateral gaps of knee extension (0°) and flexion (90°) angle were recorded in 3 different patella positions; reduced, subluxated and everted. Any gap differences of more than 3 mm were considered as a meaningful difference. Correlation between the difference with the demographic data, preoperative radiologic alignment and intraoperative data was analyzed. For statistical analysis, ANOVA and Pearson correlation test were used.Purpose
Methods
The purpose of this prospective randomized study was to compare the visible, hidden, total blood loss and postoperative haemodynamic change of subcutaneous and intra-articular indwelling closed suction drainage method after total knee arthroplasty (TKA). Patients with primary osteoarthritis, who underwent unilateral TKA were enrolled; Group A with subcutaneous (n=78) and group B with intra-articular (n=79) indwelling closed suction drainage method. Total blood loss, visible blood loss, internal blood loss, postop (day 1), 5th, 10th day hemoglobin, hematocrit levels were compared. Allogenic blood transfusion rate and complications related to soft tissue hematoma formation were additionally compared. Subcutaneous indwelling closed suction drainage method reduced both the visible blood loss and total blood loss (hemovac drainage + internal blood loss) thus decreasing the rate of allogenic transfusion. Although the minor complications such as the incidence of bullae formation and the ecchymosis were higher in the subcutaneous indwelling group, the functional outcome at postoperative 2 year did not demonstrate difference from intra-articular drainage group.
Combination of sorafenib with irradiation achieved synergistic effect with dose reduction in both 143B and HOS cell lines. This demonstrated the potential application of sorafenib in the treatment of osteosarcoma metastasis and radiation resistance. More than 20% of patients with osteosarcoma die of the disease within 5 years due to tumour relapse and metastasis. Identifying new treatment that works singly or in combination with conventional therapies is urgently required. We previously found that the Ras/Raf/MAPK pathway was associated with lung metastasis in a 143B inoculated osteosarcoma orthotopic mouse model1. Sorafenib, a multi-kinase inhibitor, has shown potent anticancer effect including in osteosarcoma2 through the inhibition of Raf-1 and other targets3. The aims of this study were to investigate effect of sorafenib on osteosarcoma cell lines with or without activated Ras/Raf/MAPK signalling and to decide whether sorafenib could enhance irradiation on these cells.Summary Statement
Introduction
The purpose of this study was to undertake a
meta-analysis to determine whether there is lower polyethylene wear and
longer survival when using mobile-bearing implants in total knee
replacement when compared with fixed-bearing implants. Of 975 papers
identified, 34 trials were eligible for data extraction and meta-analysis
comprising 4754 patients (6861 knees). We found no statistically
significant differences between the two designs in terms of the incidence
of radiolucent lines, osteolysis, aseptic loosening or survival.
There is thus currently no evidence to suggest that the use of mobile-bearing
designs reduce polyethylene wear and prolong survival after total
knee replacement. Cite this article:
Recent anthropometric studies have suggested that current design of total knee arthroplasty (TKA) does not cater to racial anthropometric differences. The purpose of this study was to investigate the exact sizing and rotational landmarks of the distal femur collected and its gender differences from a large group of healthy Southern Chinese using 3D-CT measurements, and then compare these measurements to the five total knee prostheses conventionally used in China. This study evaluated distal femoral geometry in 85 healthy Southern Chinese, included 39 females (78 knees) and 46 males (92 knees) with a mean age of 33.9 years，a mean height of 164.7 cm and a mean weight of 59.9 kg. The width of the articular surface as projected onto the transepicondylar line(ML), anteroposterior dimension (AP), the dimensions from medial/lateral epicondyle to posterior condylar (MEP/LEP) were measured. A characterization of the aspect ratio (ML/AP) was made for distal femur. The angles between the tangent line of the posterior condylar surfaces, the Whiteside line, the transepicondylar line, and the trochlear line were measured. The sulcus angle and hip center-femoral shaft angle were also measured [Fig. 1]. The data were compared with the five total knee prostheses conventionally used in China. In analyzing the data, best-fit lines were calculated with use of least-squares regression. The dimensions are summarized as the mean and standard deviation. Comparisons of dimensions between males and females were made with use of the two-sample t test. A p value of <0.05 indicated a significant effect.Background
Methods
Recent anthropometric studies have suggested that current design of total knee arthroplasty (TKA) does not cater to racial anthropometric differences. The purpose of this study was to investigate the exact sizing and rotational landmarks of the distal femur collected from a large group of healthy Southern Chinese using three dimensional computer tomographic measurements, and then compare these measurements to the known dimensions from Caucasian populations. This study evaluated distal femoral geometry in 125 healthy Southern Chinese, included 58 women (106 knees) and 67 men (134 knees) with a mean age of 35.2±8.11 years, a mean height of 165.5±7.94 cm, and a mean weight of 61.7±9.56 kg. The width of the articular surface as projected onto the transepicondylar line(ML), anteroposterior dimension (AP), the dimensions from medial/lateral epicondyle to posterior condylar (MEP/LEP)were measured. A characterization of the aspect ratio (ML/AP) was made for distal femur[Fig. 1]. The angles between the tangent line of the posterior condylar surfaces, the Whiteside line, the transepicondylar line, and the trochlear line were measured. The sulcus angle and hip center-femoral shaft angle were also measured. Known dimensions from Caucasian populations were compared with the morphologic data collected in this study[Fig. 2]. In analyzing the data, best-fit lines were calculated with use of least-squares regression. The dimensions are summarized as the mean and standard deviation. The differences of rotational landmarks and sizing between the Southern Chinese and Caucasians were assessed with use of the Student t test. A p value of <0.05 indicated a significant effect.Background
Methods
The purpose of this study was to understand the effects of terminal sterilisation and residual calcium on human demineralised bone matrix (DBM) in ectopic bone formation in nude rat. The intramuscular implantation of human DBM prepared by the Queensland Bone Bank (QBB) from four donors into eight male athymic rats was used to assess osteoinductivity. The DBM contained different levels of residual calcium and treated with or without gamma-irradiation at 11kGy. At 6 weeks post-implantation, calcium deposition was assessed by manual palpitation and radiological imaging. Tissue morphology and cellular interactions was analysed using various histological staining methods whilst protein expression of anabolic and catabolic biomarkers were examined through immunohistochemistry. All results were then analysed in qualitative, semi-quantitative and quantitative manners and tested for statistical significance. Bone formation was observed in all specimens at the gross level. This was confirmed by histology which revealed bony capsules surrounded by soft tissue in the muscle pockets and differences in tissue components. On a cellular level, variations in osteoclast expression were found between the two groups as well as amongst individual donors through statistical analysis which resulted in an imbalance of the expression of anabolic and catabolic markers. Furthermore, a positive relationship between residual calcium and new bone formation in gamma irradiated DBM samples was found. To date, no studies have compared the effect of calcium in gamma irradiated DBM. Our results suggest that gamma irradiation even at low doses and residual calcium may affect new bone formation. Taken together, this study stresses the importance of selecting ideal conditions for graft processing and the need to identify an optimal level of irradiation and remaining calcium levels that confers a balance between osteoinductivity and sterility.
Total hip arthroplasty (THA) has been applied to treat pain and disability in patients with post-traumatic arthritis after acetabular fracture for many years. However, the midterm and long-term results of THA for this unique population are still controversial. According to previous studies, we found that uncemented acetabular reconstructions were usually performed in patients who were most likely to have the best results and an abnormal acetabular structure was usually the reason for THA failure. In this study, we evaluated the midterm results of using uncement acetabular components to treat posttraumatic arthritis after acetabular fracture. In addition, we investigated the effects of different acetabular fracture treatments and fracture patterns on THA. Between January 2000 to December 2003, 34 uncemented acetabular reconstructions were performed in 34 patients for posttraumatic arthritis after acetabular fractures. Among them, 31 patients underwent complete clinical and radiographic follow-up for an average of 6.3 years (range, 3.1–8.4 years). There were 22 men and 9 women. The patients' average age was 51 ± 12 years (range, 27–74 years) at the time of arthroplasty. The average interval from fracture to THA was 5.58 ± 4.42 years (range, 0.75–17.5 years). Of the 31 patients, 19 had undergone ORIF (open-reduction group) and 12 had received conservative treatment for the acetabular fractures (conservative-treatment group). Then, 14 had simple pattern fractures (simple group) and 17 had complex pattern fractures (complex group). After midterm follow-up, the radiographic and clinic results of the different groups were compared.Background and Objective
Materials and Methods
To set up an osteosarcoma mouse model with spontaneous lung metastasis and to identify a marker of osteosarcoma metastasis and to inhibit the marker against the invasive ability of an osteosarcoma cell line. A human osteosarcoma orthotopic mouse model was set up by injecting 143B human osteosarcoma cells into mouse tibia. Type I insulin-like growth factor receptor (IGF-1R) and its downstream signalling factors were measured in samples from the primary tumor and the lung secondaries by immunohistochemistry. Human Alu mRNA expression was tested using in situ hybridization assay. A Matrigel assay was used to assess cell invasion ability under the interference of a MEK/ERK pathway specific inhibitor, U0126. All fifteen mice showed tumour mass at the left tibia and lung metastasis. Human Alu expression in the primary and secondary tumours confirmed human origin of the tumour cells. Total IGF-1R, MEK, Akt, p38 and phosphorylated MEK (p-MEK), but not p-Akt and p-p38, were positive in both local tumours and lung secondaries. Leiomyosarcoma controls expressed p-Akt and p-MEK, but not p-p38. The 143B cells treated with U0126 had significantly lower in vitro invasion ability compared with controls. The IGF-1R-MEK signalling pathway, particularly Ras/Raf/MEK/ERK, may play an important role in osteosarcoma lung metastasis, and the targeting MEK/ERK by its specific inhibitor may have a potential use in the effective treatment of osteosarcoma.
We aimed to analyze the clinical results of the patients according to joint line change who underwent navigation assisted cruciate ligament retention type mobile bearing total knee arthroplasty. From September 2004 to January 2006, cruciate ligament retention type mobile bearing total knee arthroplasties using navigation system(Orthopilot®, Aesculap) were performed for 50 knees in 45 patients (2 men, 43 women). The mean follow up period was 46(39~55) months and the mean age was 65. There was one case with rheumatoid arthritis and all other were degenerative arthritic cases. All surgeries were performed using navigation system. Proximal tibia resection was performed at the sclerotic level of medial tibial plateau. The distance from the lowest point of lateral tibial plateau (registered point) to the proximal resection plane was measured. Clinical outcome were compared between joint line elevation with more than 3 mm(20cases) and less than 3mm (30cases). The mean joint line elevation was 1.93 mm (range −1~5mm). There were no significant difference in the clinical results according to the joint line change (p>
0.05). It may be suggested that the change of joint line in the range of −1 to 5mm in cruciate ligament retention type mobile bearing total knee arthroplasty result in satisfactory clinical outcome.
This prospective study reports the midterm outcome of total hip arthroplasty performed in a consecutive series of patients using a tapered uncemented femoral component. From Nov. 2001 to Apr. 2006, total hip arthroplasties were performed in 138 patients (150hips). The clinical records and the routine serial radiographs of these patients were monitored closely over a 1-year period. Clinical evaluation was done by Harris hip score before surgery and at last follow-up. Radiological evaluation was done on plain radiographs. The average follow up period was 4.05 years. There was a significant improvement in functional outcome of these patients as measured by Harris hip score. There were no revisions for aseptic loosening of the femoral component in this series, accounting for an overall survivorship of 100%. The study confirms that the midterm outcome of this stem is excellent, with no revisions.
Achieving the correct amount of femoral component rotation has become the basic objective of surgical techniques in total knee arthroplasty and this can be done either with a measured resection technique or indirectly by flexion/extension gap equalization technique. We demonstrated the variabilities of the reference axes (PCA, WSL, TEA) when soft tissue tension was managed intraoperatively by navigation system. The mean angle of transepicondylar line, Whiteside’s line, posterior condylar line from the proximal tibia resection plane were 1.29 ± 3.67 (mean ± SD; range 7 to 10.5), 3.90 ± 4.17 (mean ± SD; range 3 to 15.5), −4.03 ± 2.71 (mean ± SD; range 9.5 to 1.0) respectively. Coefficient of variation(CV(%); std/mean × 100) were 283, 106, 67 respectively. Out of the 3 reference axes widely used for femoral component rotation, angles from proximal tibia resection plane to posterior condylar line showed the least range of variance.
Fracture healing involves many local and systemic regulatory factors. Progress in identifying signaling events downstream has been made with the discovery of a novel family of proteins, the Smad, as TGF-ß/activins/BMPs signal transducers. Smads are the vertebrate homologs of Eighteen 3-month old female CD-COB rats were used. A standard closed fracture was made in the mid-shaft of right femur using a 3-point bending device. The left limb served as the non-fracture control. The rats were divided into 3 groups (6 per group) and sacrificed at day 3, 10 and 28 after fracture. The femurs were harvested, fixed in buffered formalin for 48 hours and decalcified with 10% formic acid-formalin solution. The decalcified tissues were embedded in paraffin and 5μm sections were cut onto silane-coated slides. Representative slides from each block were stained with routine haematoxylin and eosin (H&
E). Sections were cut for immunohistochemistry for protein marker expression by a standard procedure for Smads and BMP 4 and 7. Sections were viewed and analysed by colour video image analysis using a 40x objective, a 10x eyepiece, and a fixed frame of 128 × 128 pixels (49152.0 μm2). Ten fields per slide were examined. Smad proteins (Smads 1, 4, and 6) were expressed during the early stages (day 3) of fracture healing by bone marrow stromal cells, osteoblasts, fibroblasts and chondrocytes located in the intramembranous and endochondral ossification regions around the fracture site. Differential expressions of individual Smads, particularly Smad 1 and Smad 6, at different time-points (Smad-1 was higher than Smad-6 at day 3, whilst Smad-6 was much higher than Smad-1 at day 10) suggest that Smad proteins are not simply BMP signal transducers. Smads may also be responsible for up- and/or down-regulation of transcriptional events during the intramembranous and endochondral ossification. Smad-4, a Co-SMAD, expression newly formed bone and cartilage suggests an additional function beyond the signal transduction in rat fracture healing. BMP-4 and BMP-7 were highly expressed at day 3 and 10. BMP-7 expression was greater than BMP-4 at day 3 but switched by day 10 (BMP-4 >
BMP-7). Smads represent a new level where specific therapeutic strategies can be targeted considering the interactions with a number of BMPs.
The rate of success of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head may be improved if patients are preselected using MRI. We have used three criteria for selection for osteotomy (i) minor collapse of the infarcted area, loss of congruity or the crescent sign, without narrowing of the joint space or acetabular involvement (ii) patients younger than 55 years and with a painful hip (iii) patients with an intact area constituting an arc of more than 120° between the central vertical line of the femoral head and the posterior or anterior margin of the necrotic portion as seen on a midsagittal MRI. Seventeen patients were selected, with a follow-up of more than 42 months. A bone scan four weeks after operation showed adequate perfusion of the proximal segment in all hips. The hip score of Merle d’Aubigné et al improved from 13.5 points before operation to 17.2 points at the latest follow-up. Further collapse of the femoral head did not occur. The use of MRI instead of plain radiographs for the selection of patients has improved the success rate of transtrochanteric rotational osteotomy.
