Revision total hip arthroplasty combined with subtrochanteric shortening osteotomy: case report.

Revision surgery is one of the most difficult reconstructive challenges facing orthopaedic surgeons; therefore, many new techniques and implants are needed to ensure that such patient can be successfully treated. We report a 66-year old female with a chronic dislocated bipolar hip prosthesis. She underwent a revision total hip arthroplasty combined with V-shaped subtrochanteric shortening osteotomy. This report demonstrates that V-shaped subtrochanteric shortening osteotomy can be used for revision surgery. Nevertheless, this technique is not suitable for all hip revisions, and the indications and various possible procedures and devices should be carefully considered to select the best treatment for each patient. We believe that the current report provides evidence supporting a new technical option for complex cases during revision THA.

Failure analysis of alumina on alumina total hip arthroplasty with a layered acetabular component: minimum ten-year follow-up study.

This prospective study reports the outcome of total hip arthroplasty (THA) performed in a consecutive series of patients using an alumina ceramic on a ceramic-layered component (Alumina-Bearing-Surface system). The cohort consisted of 270 hips in 229 patients. The study evaluated the clinical and radiological results over a mean follow-up of 11.4 years. Revision THA was performed on 58 hips, including alumina alternative failure in 50 hips, loosening in 4 hips, recurrent dislocation in 2 hips, stem neck fracture in 1 hip and hematoma in 1 hip. The survival rate was 68% with revision for any reason as the end point. The risk factors of implant failure are the preoperative range of motion of the hip joint and postoperative dislocation.

Prospective study of physical activity and quality of life in Japanese women undergoing total hip arthroplasty.

BACKGROUND: Improvement in quality of life (QoL) in patients who went through total hip arthroplasty (THA) is well studied, while the number of studies on improvement in actual daily activity in THA patients is limited. The purpose of the study was (1) to describe the pre- to postoperative changes in physical activity (PA) levels, (2) compare PA levels with healthy controls, and (3) examine the association between PA levels and QoL in Japanese women undergoing THA. METHODS: PA was measured by pedometers, and QoL was assessed by the Short-Form 8 and the Oxford Hip Scale questionnaires. Consecutive patients undergoing primary THA at Saga University Hospital, Japan, in 2008 were eligible for the study. QoL and pedometers with accelerometers were mailed to THA patients 1 month pre-THA and 6 and 12 months post-THA. The control group completed a single assessment of questionnaires and pedometers. RESULTS: Thirty-eight THA patients completed the study. Preoperatively, the patient group had significantly lower QoL scores than the comparison group. However, these differences disappeared by 12 months post-THA. When improvement of PA function in THA patients was compared with healthy controls, light PA was already 78 % of the healthy controls at the pre-THA period and improved to 90 % at 12 months. In contrast, moderate PA was 27 % of the controls and rose to 77 % by 12 months, and vigorous PA remained low throughout the study period. PA was correlated with QoL scores. CONCLUSION: The study shows the relative recovery process of PA indicators in THA patients and the contribution of PA to the improvement of QoL.

Total hip arthroplasty combined with double-chevron subtrochanteric osteotomy.

BACKGROUND: Subtrochanteric femoral shortening and corrective osteotomy are regarded as an integral part of total hip arthroplasty for a completely dislocated hip or severe deformity of the proximal femur. Alternative femoral osteotomy techniques-transverse, oblique, step-cut, and V-shaped, have been described. METHODS: In this series, we performed 22 cementless total hip arthroplasties combined with double-chevron subtrochanteric osteotomies between 1997 and 2002. There were 17 females and 2 males. Their average age at the time of the operation was 59 years (range 41-74 years). Thirteen hips were completely dislocated, 8 hips needed treatment after a proximal femoral osteotomy, and there was 1 case of hip ankylosis. RESULTS: The mean length of the operation was 128 min (range 80-215 min). Mean total blood loss was 1442 g (range 809-2007 g), which included both the intraoperative blood loss and postoperative blood loss. After an average of 7.6 years of follow-up, the Japanese Orthopaedic Association Hip Score improved from 48 to 79. Three types of complication were observed. There were 4 early dislocations, 3 proximal splits, and 1 nonunion at the osteotomy site. CONCLUSIONS: Our study shows that acceptable results are obtained from double-chevron subtrochanteric osteotomy for subtrochanteric femoral shortening and corrective osteotomy. However, total hip arthroplasty combined with subtrochanteric osteotomy is a technically demanding treatment option.

Foot pressure distribution in patients with gonarthrosis.

BACKGROUND: When standing, leg alignment is controlled by supinating or pronating the subtalar joint, corresponding to valgus or varus deformity of the knee joint. However, in the gait cycle, it is not clear whether the abnormal alignment can be compensated. OBJECTIVE: The purpose of this study was to evaluate the control of leg alignment in the latter half of the gait cycle. METHODS: Forty-six patients (46ft) with unilateral gonarthrosis (16 men, 30 women; mean age, 69 years) were evaluated for foot pressure distributions of the forefoot and midfoot. The apparatus used was a walkway in which a tactile force- and pressure-measurement system was installed. Patients were classified by femorotibial angle, pronation-supination index (PSI), foot pressure distribution of the point of the metatarsal head, and passage point of the center of pressure (COP) at the toe. RESULTS: A larger femorotibial angle was associated with a larger PSI, and contact such that the load is applied more strongly to the pressure points of the metatarsal heads laterally. In addition, with a larger femorotibial angle, COP at the toe tended to pass through the second toe. In other words, foot sole contact is significantly more lateral with varus knee, whereas foot sole contact tends to be more medial with valgus knee. CONCLUSIONS: Analysis revealed that severe abnormal leg alignment was not sufficiently compensated for by the forefoot and midfoot in the latter half of the gait cycle. When treating the forefoot and midfoot, precautions are necessary in patients with knee deformities.

Seasonal trends in the incidence of hip osteoarthritis in Japanese patients.

PURPOSE: There is an association between winter birth and developmental dysplasia of the hip, formerly termed congenital dislocation of the hip. The purpose of this study was to clarify the relationship between the month and season of birth and hip osteoarthritis in Japanese patients who had undergone total hip arthroplasty or transpositional osteotomy of the acetabulum. METHODS: One thousand eight hundred and 52 female patients that presented for the surgical treatment of hip osteoarthritis between 1999 and 2005 were included in this study. Female out-patients who were seen at the initial visit during same period were used as controls to correct the bias of the month of birth. RESULTS: There was a significant deviation of the observed number of births from the expected values calculated on a monthly basis (p<0.001). A comparison by seasons (periods of 3 months) revealed more births than expected in winter (p<0.001). The risk of hip osteoarthritis was significantly associated with the month of birth. Namely, it was highest for births in January (p<0.001). CONCLUSIONS: These data clearly revealed that the prevalence of hip osteoarthritis was significantly higher in those patients born in winter. The seasonal trend in hip osteoarthritis might be due to the winter prevalence of congenital dislocation of the hip in childhood.

The biomechanical effect of the collar of a femoral stem on total hip arthroplasty.

To investigate the biomechanical effect of collars, finite element analyses are carried out through two hip joints that are implanted using collared and collarless stems, respectively, and an intact hip joint model. For the analyses, the sacrum, coxal bone, and the cancellous and cortical bones of a femur are modelled using finite elements based on X-ray computed tomographic images taken from a 27-year-old woman. From the results, it is found that a collar with perfect calcar contact prevents stem subsidence and decreases the proximal-lateral gap and the lateral stem tilting. Therefore, it can impart reasonable biomechanical stability for total hip arthroplasty. However, its low load transmission ability and increased stem tilting effect due to the imperfect contact between the collar and the calcar are found to be serious problems that need to be solved. Results of clinical follow-up are presented for supporting the computational results.

Apatite-forming ability of titanium compound nanotube thin films formed on a titanium metal plate in a simulated body fluid.

We compared the apatite-forming ability of a sodium titanate nanotube thin film, an anatase-type titanium dioxide nanotube thin film, and a silver nanoparticle/silver titanate nanotube nanocomposite thin film, in simulated body fluid. The ability of the silver nanoparticle/silver titanate nanotube nanocomposite thin film is slightly higher than that of the anatase-type titanium dioxide nanotube thin film and significantly higher than that of the sodium titanate nanotube thin film. The high ability of the silver nanoparticle/silver titanate nanotube nanocomposite thin film is a newly observed phenomenon, which is probably due to the crystal structure of silver titanate--specifically, to the surface atomic arrangement, the large amount of Ti-OH formed on the nanotube surface, or both. The anatase-type titanium dioxide nanotube thin film and the silver nanoparticle/silver titanate nanotube nanocomposite thin film may have bright prospects for future use in implant materials such as artificial joints. The silver nanoparticle/silver titanate nanotube nanocomposite thin film is particularly promising for its antibacterial properties.

Effect of bacterial media on the evaluation of the antibacterial activity of a biomaterial containing inorganic antibacterial reagents or antibiotics.

Several studies have been performed to assess the effectivesness of the antibacterial coating of a biomaterial to reduce surgical site infection. However, evaluations of these materials are inconsistent, and therefore it is difficult to compare their antibacterial performance. In this study, we evaluated the influence of different media such as nutrient broth (NB), Mueller-Hinton broth (MHB) and fetal bovine serum (FBS) on the antibacterial activity of AgNO3- or gentamicin-added bone cement using a modified ISO 22196 standard to devise a method to evaluate the antibacterial activity of biomaterials in vitro. The antibacterial activity results against Staphylococcus aureus and Escherichia coil were different in each medium. The antibacterial activity of AgNO3 in FBS was lower than the other media, whereas the antibacterial activity of gentamicin in FBS was higher than in the other media. It was assumed that the fluctuating antibacterial activity was influenced by serum components. The results showed that the ISO 22196 antibacterial evaluation method is suitable to evaluate antibacterial biomaterials after modifying the medium to FBS.

Organotypic culture of human bone marrow adipose tissue.

The precise role of bone marrow adipose tissue (BMAT) in the marrow remains unknown. The purpose of the present study was therefore to describe a novel method for studying BMAT using 3-D collagen gel culture of BMAT fragments, immunohistochemistry, ELISA and real-time reverse transcription-polymerase chain reaction. Mature adipocytes and CD45+ leukocytes were retained for >3 weeks. Bone marrow stromal cells (BMSC) including a small number of lipid-laden preadipocytes and CD44+/CD105+ mesenchymal stem cell (MSC)-like cells, developed from BMAT. Dexamethasone (10 micromol/L), but not insulin (20 mU/mL), significantly increased the number of preadipocytes. Dexamethasone and insulin also promoted leptin production and gene expression in BMAT. Adiponectin production by BMAT was <0.8 ng/mL under all culture conditions. Dexamethasone promoted adiponectin gene expression, while insulin inhibited it. This finding suggests that dexamethasone, but not insulin, may serve as a powerful adipogenic factor for BMAT, in which adiponectin protein secretion is normally very low, and that BMAT may exhibit a different phenotype from that of the visceral and subcutaneous adipose tissues. BMAT-osteoblast interactions were also examined, and it was found that osteoblasts inhibited the development of BMSC and reduced leptin production, while BMAT inhibited the growth and differentiation of osteoblasts. The present novel method proved to be useful for the study of BMAT biology.

In vivo antibacterial and silver-releasing properties of novel thermal sprayed silver-containing hydroxyapatite coating.

One of the serious postoperative complications associated with joint replacement is bacterial infection. In addressing this problem, we have previously described the development of a novel thermal spraying technology combining silver (Ag) showing antibacterial activity with hydroxyapatite (HA) displaying good biocompatibility and osteoconductivity, and reported the in vitro properties. This study evaluated serum Ag ion concentrations and antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) using a subcutaneous rat model. HA loaded with 3 wt % of silver oxide (Ag-HA) and plain HA were sprayed on the surface of titanium disks. Ag-HA- or HA-coated samples were implanted into the back subcutaneous pockets of male Sprague-Dawley rats. Mean serum Ag ion concentration in the Ag-HA group increased to more than 50 ppb by 48 h after implantation, then decreased gradually to baseline levels. Mean (+/- standard error of the mean) number of viable MRSA on HA coating was (1.5 +/- 0.5) x 10(5), which is significantly more than the (1.1 +/- 0.4) x 10(4) on Ag-HA coating (p < 0.001). Ag-HA coating offers good abilities to release Ag ions and kill MRSA in vivo.

Factors influencing the improvement of gait ability after total hip arthroplasty.

We aimed to investigate the factors influencing gait improvement in the patients who had undergone total hip arthroplasty. We performed gait analysis on 43 female patients with unilateral hip osteoarthritis. All the patients were analyzed before and at 2, 6, and 12 months after the surgery. There were significant reductions in spatiotemporal parameters in the patients with hip osteoarthritis compared with the control group. The mean values of the spatiotemporal parameters of the patients showed considerable improvement by 12 months after surgery; however, they did not reach the same values as those observed in the healthy subjects. The stage of osteoarthritis and the changes in the leg-length discrepancies were the factors that most influenced gait improvement after total hip arthroplasty throughout the follow-up period.

Antibacterial properties of nanostructured silver titanate thin films formed on a titanium plate.

Antibacterial activity of various surfaces against methicillin-resistant Staphylococcus aureus (MRSA) was studied. Sodium titanate thin film with a porous network structure and sodium titanate nanotube thin film were formed on titanium surfaces through the reaction of titanium plates with NaOH solutions. Through a silver ion-exchange treatment, Na(+) ions in sodium titanate were exchanged with Ag(+) ions in silver acetate solution, along with the loading of silver nanoparticles on the titanate surfaces. Results of silver ion elution tests of the thin films in fetal bovine serum solution indicate that the release period and the number of silver ions released from the silver titanate thin films can be controlled by altering the crystal structure, nanostructure, and thickness of the titanate phase. The silver ion-exchanged titanate thin films showed high antibacterial activity against MRSA. It was also revealed that although the crystal structure of titanate itself has no large antibacterial effect, higher antibacterial activity mainly arises from the silver ions held in the interlayer spacing of the titanate. The obtained results should aid the development of more convenient and inexpensive antibacterial implants.

Subcutaneous Achilles tendon rupture in an eighty-year-old female with an absence of risk factors.

Achilles tendon ruptures rarely occur in patients over 80 years of age. However, it is unclear what treatment, surgical or conservative, is suitable for such an Achilles tendon rupture in the elderly. In addition, the clinical results of an Achilles tendon rupture in the elderly are disappointing. We report here the case of a subcutaneous Achilles tendon rupture in an eighty-year-old, healthy female, who returned to her previous level of activity following surgical treatment. Additional case reports of other instances of successful treatment are needed to help establish the optimal treatment protocol for an Achilles tendon rupture in the elderly.

A study of the effect of the femoral head diameter on prosthetic hip joint dislocation using a hip-joint motion simulator.

Prosthetic hip joint dislocation phenomenon is generated by the hip joint simulator and the effect of the femoral head diameter is studied under the same condition which is similar to the condition in daily activities. Impedance control is applied to control the hip joint motion and the joint contact force simultaneously in order to take into account the constraint caused by surrounding tendons, muscles, and a joint capsule of the hip joint. The experimental results show that the hip joint dislocation phenomenon is generated by the simulator and the obtained results about the effect of the femoral head size agree with those of the other research.

Serum concentrations of interleukin-6 in patients following unilateral versus bilateral total knee arthroplasty.

BACKGROUND: Surgical stress is known to affect body temperature, white blood cell (WBC) count, C-reactive protein (CRP), and interleukin-6 (IL-6). The aim of the present study was to investigate which parameter is most suitable for quantitative analysis of surgical stress. METHODS: Unilateral total knee arthroplasty (U-TKA) and bilateral TKA (B-TKA) were selected for the subjects of this study because the B-TKA creates approximately double the surgical stress of the U-TKA. The temperature, WBC count, CRP, and IL-6 in the blood were measured pre- and postoperatively in both groups. The IL-6 in the drainage fluid was also measured after the operation. RESULTS: The temperature, WBC count, CRP, and IL-6 in the blood significantly increased on the first day after the operation in both groups. There were significant differences between the two groups in the WBC count (P < 0.05) and the IL-6 level in the blood (P < 0.05) on the first day after the surgery. There were no significant differences between the two groups for the CRP and IL-6 levels in the drainage fluid. The relative proportions--(B-TKA/U-TKA) x 100 (%)--were 170.4% for the operating time, 219.4 % for total blood loss, 200.0% for blood transfusion, 100.3% for temperature, 128.9% for WBC count, 127.4% for CRP, and 246.5% for the IL-6 level in the blood. CONCLUSIONS: The serum IL-6 level may best reflect surgical stress and could therefore be a quantitative marker of surgical stress.

Development of novel thermal sprayed antibacterial coating and evaluation of release properties of silver ions.

Several studies have addressed the use of antibacterial coating to reduce implant-associated infections. In this study, novel silver (Ag)-containing calcium-phosphate (CP) coating technology based on the thermal spraying method was developed. The coating's physical and chemical properties, in vitro antibacterial activity, hydroxyapatite (HA)-forming ability, and release of Ag ions were evaluated. An amorphous structure of the coating was confirmed by X-ray diffraction, and Ag residue in the coating was determined by elementary analysis. The coating showed strong antibacterial activity to methicillin-resistant Staphylococcus aureus in fetal bovine serum (FBS) along with HA-forming ability in simulated body fluid. Therefore, it is expected that the coating would confer antibacterial and bone bonding abilities to the implant surface. Time course release testing of Ag ions from the coating on immersion in FBS showed pronounced Ag release for up to 24 h after immersion, with consistent strong antibacterial activity at the early postoperative stage. In repeated testing, the amount of released Ag ions was about 6500 parts per billion (ppb, microg/L) for the first release test, after which it gradually decreased. However, retention of significant release of Ag ions after a sixth repeat implies that Ag release from the coating is slow in FBS.

Mature and activated osteoclasts exist in the synovium of rapidly destructive coxarthrosis.

We compared histological and functional findings in rapidly destructive coxarthrosis (RDC) and slowly progressive osteoarthritis (OA) to investigate whether osteoclasts contribute to the extensive bone destruction observed in RDC. A histological analysis of tissue specimens from the synovium obtained from 10 cases of RDC and 40 cases with OA of the hip was performed after staining for tartrate-resistant acid phosphatase (TRAP). The cells isolated from these tissue specimens from the synovium were cultured for 24 h, and the numbers of TRAP-positive giant cells were counted. Thereafter, we performed a resorption pit formation assay by isolated cells cultured on dentine slices for 7 days. The number of TRAP-positive multinuclear giant cells present in the synovial membrane obtained from RDC patients was significantly larger than that obtained from OA patients. Large lacunar resorption pits were only seen on the dentin slices in a culture of isolated cells from RDC patients without any stimulators. This is the first report, to our knowledge, to reveal that mature and activated osteoclasts exist only in the synovium of RDC and not in the OA synovium. This result might suggest that the underlying mechanism of RDC is therefore associated with osteoclastogenesis in the synovium.