Aims

Although there are various pelvic osteotomies for acetabular dysplasia of the hip, shelf operations offer effective and minimally invasive osteotomy. Our study aimed to assess outcomes following modified Spitzy shelf acetabuloplasty.

Background

Total knee arthroplasty has been performed even for severe valgus knee. All ligaments around knee must be balanced to obtain good clinical results. Especially medial collateral ligament plays a role as a stabilizer. For severe valgus knee, however, deep medial collateral ligament (dMCL) located closely to the articulating tibial surface [Fig. 1] can be damaged by bone resection in standard tibial osteotomy which may leads to progress valgus deformity.

Introduction

Highly cross-linked polyethylene (HXLPE) was developed to reduce the wear of articular-bearing surfaces in total hip arthroplasty (THA). This study aimed to compare the mean linear wear of HXLPE with a 22.225 mm diameter zirconia head with that of conventional polyethylene (CPE) with a 22.225 mm diameter ortron head.

Introduction

Antibiotic-loaded acrylic cement (ALAC) is employed in the treatment or prevention of infected total hip arthroplasty (THA). We have administered vancomycin (VCM) as the ALAC for the treatment of THAs with methicillin-resistant Staphylococcus aureus, or for the prevention of THAs with high risks. This study aimed to evaluate the serum concentration of VCM from ALAC in THA or cement beads.

Introduction:

The diagnosis of implant-associated infections is challenging, and the conventional culturing of periprosthetic tissue has been the gold standard for diagnosis of implant-associated infections. However, conventional diagnostic tests are inaccurate because the pathogenesis of implant-associated infection is related to microorganisms growing in biofilms. We compared culture of samples obtained by sonication of explanted implants to dislodge adherent bacteria from implants with conventional culture of periprosthetic tissue. The purpose of this study is to evaluate the results of sonication that is microbiological diagnostic method for implant-associated infections.

Introduction

It is still controversial whether one or two-stage revision should be indicated for deeply infected hip prosthesis, and there are no scoring systems for the decision of them. An assessment system for the treatment of deeply infected hip prosthesis was evaluated for the patients who had undergone one or two-stage revision total hip arthroplasty (THA).

The treatment of rheumatoid arthritis (RA) has recently seen a paradigm shift with the introduction of biologic therapy, but there is concern that this will result in an increased incidence of infection. The occurrence of infection in RA patients who have undergone biologic therapy has recently been documented in a few reports, but this is the first report of Salmonella infection after total knee arthroplasty (TKA) in a RA patient receiving etanercept therapy. Here we report the successful treatment of a rare case of Salmonella septic arthritis.

A 61-year-old man with a 4-year history of RA was treated with methylprednisolone and methotrexate, and he consulted us because of right gonalgia. Treatment with infliximab was started, but as this was not effective, his medication was changed sequentially to etanercept 6 months later. Finally, TKA was performed on the right knee with antibiotic-loaded acryl cement (ALAC). The postoperative course was uneventful, etanercept was administered routinely from the 2nd postoperative week. The patient was discharged after 4 weeks. Five weeks after TKA, however, the patient visited us because of acute swelling and tenderness around the right knee. His laboratory values included a white blood cell count of 9300/mm3, an erythrocyte sedimentation rate of 81.0 mm/h and a C-reactive protein level of 11.3 mg/dl. Fluid obtained by joint aspiration was cloudy and dark-yellow, and prosthetic joint infection was diagnosed. The patient underwent emergency debridement by arthroscopic surgery, followed immediately by injection of 0.5 g carbapenem every 12 hours and continuous closed irrigation-suction of the joint for 2 weeks. Culture of the joint fluid revealed Salmonella enteritidis infection, which was not sensitive to aminoglycoside which we used as ALAC. The patient was treated with intravenous carbapenem for 3 weeks, oral levofloxacin at a daily dose of 300 mg for 2 weeks successively, and oral minocycline at 200 mg daily for 3 months. At follow-up 12 months after surgery, physical and blood examinations and plain radiographs demonstrated no recurrence of the infection, and the patient has resumed taking etanercept. The range of flexion in the treated knee is 0 to 145 degrees.

Salmonella arthritis is classified as septic arthritis and reactive arthritis, and septic arthritis is more likely if Salmonella is identified by culture of joint fluid. Salmonella septic arthritis has not been considered an intraoperative contaminant during joint replacement. Recently, it has become apparent that biologic therapies can play major roles in the pathogenesis of RA, and also that immuno-suppressive drugs may become risk factors for Salmonella septic arthritis. In conclusion, our patient had a successful outcome after prompt debridement and treatment with appropriate antibiotics, without the need for implant removal. It is important to be mindful of the possibility of infection and to carry out surgery immediately if a patient presents with symptoms after biologic therapy.

Objective

Destruction and deformity in both PIP and MP joints are not uncommon and cause sever disabilities. Arthroolasty of the MP joint combined with arthrodesis of the PIP joint are the usual choice for this condition. Some motion in ulnar digits provides great benefits for rheumatoid patients. We report implant arthroplasty of the PIP joint and also simultaneous replacement of PIP and MP joint in same finger.

Material & Methods

Twenty-five joints in 15 patients underwent PIP arthroplasty either with silicone or surface replacement implant. Twelve PIP joints in 6 patients used Silicone implant (6 Swanson and 6 Avanta) alone and mean follow up was 42(6–84) months. New cementless surface implant (Self Locking Finger Joint, SLFJ) were developed and clinically used for about 3 years. Because of the stem design, SLFJ are able to use both PIP and MP joint simultaneously or combined with silicone implant. Four PIP joints in 3 patients used SLFJ alone and 6 patients underwent both PIP and MP joint with implant simultaneously. Combination of SLFJ PIP and silicone MP was 4 finger in 2 hand, SLFJ PIP and SLFJ MP was 3 finger in 2 hand, silicone PIP and SLFJ MP was 3 finger in 2 patients and silicone PIP and silicone MP was 1 finger. Mean follow up for SLFJ in either PIP or MP was 18(4–37) months.

Results

Average arc of the PIP with silicone implant alone was 38(10–50 ° and SLFJ alone was 55(45–60) °. One PIP SLFJ dislocates immediate after surgery and was converted silicone later on. Of 7 SLFJ with combined PIP and MP arthroplasties, 2 PIP lost motion completely, one PIP move only 15°, 4 PIP move 75 °in average. Four silicone PIP combined with MP arthroplasties move 45°in average.

One PIP SLFJ had breakage in stem legs, which believed to occur during interaction of stem insertion from both side of the basal phalanx, and was seen at immediate post op X-ray. There was one instability in index replaced with SLFJ for sever Swan neck deformity and no infection. Patient satisfaction for simultaneous replacement in PIP and MP joint were excellent except one whose age was 72.

Discussion

Stability of the PIP joint in index finger is important for pinch and PIP motion of ring and little fingers are required for grip motion. Although arthrodesis of the PIP joint were performed more often and functional improvement usually obtained compared to pre-operative condition, ulnar 2 digits better to preserve some motion in the PIP joint as long as there is a possibility, and especially for the young patients. The results of the simultaneous replacement in PIP and MP joint seems discourage, however, when considering the severity of the deformities of this series, there is a good chance in the future. We will improve implant design and surgical technique as well as post-operative therapy, and continue to challenge the simultaneous replacement of PIP and MP joint.

The results of 278 consecutive primary total hip arthroplasties performed with bone grafting for ace-tabular bone deficiencies were reviewed at an average of 9.0 years (range, 5–23) after surgery. All patients had underlying developmental dysplasia of the hip. For all hips, the grafts used were from the patients’ own resected femoral heads. All but three grafts were screwed to the supero-lateral aspect of the acetabular roof, the exceptions being grafts without internal fixation. Kaplan-Meier survivorship analysis predicted a rate of survival of the acetabular component at 10 years of 97% (95% confidence interval (CI), 94–100%) with revision for aseptic loosening as the endpoint, and of 82% (95% CI, 76–89%), when radiological loosening was used. Trabecular reorientation, as an indicator of graft incorporation, was seen in 89% of the joints between 1.5 and 5 years (mean 3 years), and delayed up to 7 years. Parametric survivorship analysis using the Cox proportional-hazards model indicated that trochanteric non-union, lateral placement of the socket, and delayed trabecular re-orientation of the bone graft, were risk factors for loosening of the acetabular component. Autogenous acetabular bone grafting will be of value for long-term success and has good potential for additional improvement of the results, provided these three risk factors are reduced. In order to promote the trabecular reorientation, we have gradually improved the surgical technique including sizing of bone graft and adaptation technique. By these alterations of the surgical technique, trabecular reorientation of the 51 joints operated after 1993 was completed by 4 years after surgery.

We evaluated the long-term results of a modified Spitzy shelf operation for secondary osteoarthritis in 119 hips with a mean follow-up of 23.8 years. The mean age of the patients at the time of surgery was 25 years. Preoperative osteoarthritic change, the age at operation and shelf height were important factors in determining the outcome. Of the 61 hips in the pre-stage (three) and the initial stage (58) of osteoarthritis, 53 (87%) had good results, compared with only 30 (51%) of 58 hips with advanced osteoarthritis. Of the latter, 72% of those aged less than 25 years had good results compared with only 40% of patients aged over 25 years. The shelf height in the group with good results was significantly lower than in those with poor results. This operation is a safe procedure and indicated for acetabular dysplasia or subluxation of the hip with early osteoarthritic change in patients aged less than 25 years.

We evaluated the efficacy and biocompatibility of porous apatite-wollastonite glass ceramic (AW-GC) as an intramedullary plug in total hip replacement (THR) for up to two years in 22 adult beagle dogs. Cylindrical porous AW-GC rods (70% porosity, mean pore size 200 3m) were prepared. Four dogs were killed at 1, 3, 6 and 12 months each and six at 24 months after implantation.

Radiological evaluation confirmed the efficacy of porous AW-CG as an intramedullary plug. Histological evaluation showed osteoconduction at one month and resorption of the porous AW-GC, which was replaced by newly-formed bone, at 24 months. Our findings indicate that porous AW-GC can be used clinically as an intramedullary plug in THR.

Although the technique of autogenous acetabular bone grafting has been widely used to augment containment of the acetabulum in total hip arthroplasty (THA) for developmental dysplasia, the role of this technique in improving long-term results remains controversial.

We present the long-term results of cemented THA with acetabular bone grafting in 112 patients (133 hips) in order to clarify the factors which affect the outcome. The mean follow-up was for 12.3 years (8 to 24). Kaplan-Meier survivorship analysis predicted a rate of survival of the acetabular component at 15 years of 96% (95% confidence interval (CI) 92 to 99) with revision for aseptic loosening as the endpoint, and of 75% (95% CI 65 to 85) when radiological loosening was used. Parametric survivorship analysis using the Cox proportional-hazards model indicated that trochanteric nonunion, lateral placement of the socket, and delayed trabecular reorientation of the bone graft were risk factors for loosening of the acetabular component.

Our findings have shown that autologous acetabular bone grafting is of value for long-term success provided that the risk factors are reduced.

We have developed a new drug delivery system using porous apatite-wollastonite glass ceramic (A-W GC) to treat osteomyelitis. A-W GC (porosity, 70% and 20% to 30%), or porous hydroxyapatite (HA) blocks (porosity 35% to 48%) used as controls, were soaked in mixtures of two antibiotics, isepamicin sulphate (ISP) and cefmetazole (CMZ) under high vacuum.

We evaluated the release concentrations of the antibiotics from the blocks. The bactericidal concentration of ISP from A-W GC was maintained for more than 42 days, but that from HA decreased to below the detection limit after 28 days. The concentrations of CMZ from both materials were lower than those of ISP. An in vivo study using rabbit femora showed that an osseous concentration of ISP was maintained at eight weeks after implantation. Osteoconduction of the A-W GC block was good.

Four patients with infected hip arthroplasties and one with osteomyelitis of the tibia have been treated with the new delivery system with excellent results.

We have developed a bioactive bone cement (BA cement) consisting of Bis-GMA resin and bioactive glass powder. It has high compressive and tensile strengths, a low curing temperature and its bioactivity allows it to bond directly with bone.

We operated on the 18 femora of nine mongrel dogs for intercalary replacement of part of the bone by a metal prosthesis using either PMMA cement or BA cement for fixation. Three dogs were killed at each of 4, 12 and 26 weeks after surgery for the evaluation of fixation strength by a push-out test and for histological examination by Giemsa surface staining and SEM.

Fixation strengths with PMMA cement at 4, 12 and 26 weeks after surgery were 46.8 ± 18.9, 50.0 ± 24.7, and 58.2 ± 28.9 kgf (mean ±SD), respectively. Those with BA cement were 56.8 ± 26.1, 67.2 ± 19.2, and 72.8 ± 22.2 kgf, respectively. Fibrous tissue intervened between bone and PMMA cement but BA cement had bonded directly to bone at 12 and 26 weeks. This suggests that BA cement will be useful in providing long-lasting fixation of implants to bone under weight-bearing conditions.

Ultrasound can be used to outline the spinous processes and the laminae, and thus to measure axial rotation. Using our own technique, we measured vertebral rotation in 47 patients with idiopathic scoliosis. There was a strong linear relationship between the Cobb angle and the rotation of the apical vertebra in untreated patients, but this relationship was lost in patients who had had brace treatment. Vertebral rotation can easily be measured by ultrasound. This is a harmless and fairly rapid investigation which can be used at routine follow-up examination of patients with idiopathic scoliosis.