Introduction

Patients undergoing total hip arthroplasty (THA) stand in the danger, a particularly high risk for venous thromboembolism (VTE). Fondaparinux and edoxaban, which inhibit FXa, indirectly and directly, respectively, have been used for prevention of VTE after THA in Japan. The aim of this study was to compare the efficacy of fondaparinux and edoxaban for VTE after elective THA in Japanese patients.

INTRODUCTION

Venous thromboembolism (VTE), especially, deep vein thrombosis (DVT) in lower extremities, often seriously combined with pulmonary embolism (PE), is a major and critical complication after total hip arthroplasty (THA). For better disgonsis of VTEs, D-dimer test is one of the useful methods. The aim of this study was to evaluate the efficacy of D-dimer levels before THA.

Revision of the femur component in total hip arthroplasty using impaction bone grafting (IBG) was performed in 140 hips of 136 patients in our hospital. The mean age of the patients at the time of the femoral component revision was 72 years. The median of follow-up time was 80 months. 140 hips were operated with use of YU stem (Yamagata university stem, collared, not polished)104, Exeter stem 2, CPT 2, Restration 5, and others 27.

The length of the stem was a regular stem 114, a long stem 26. The complications related to the revised hip consist of infection 5, dislocation 8, DVT9, fracture during operation 11. Four stems were revised due to infection and two due to loosening.

YU stem is made of titanium alloy with collar, the surface of that stem is not polished and Ra is 0.27 μm. We started to apply IBG in 1994, there were no IBG instrument set and system available such as Exeter, CPT in Japan, so we had used YU stem. However, the result with YU stem was preferable and the implant was stable. Thus, we have been using YU stem. In the process, there have been a number of improvements in IBG instrument and system since we started using them. At first, all medullar cavity is filled with grafted bone up to proximal entry with moderate impaction. Along with guide pin, new medullar canal is made by drilling and insert stem tamper into the space to tighten the layer of impaction, then cement fixation of the stem is performed. This method made the operative time short and operative technique easy.

There are several advantages of IBG technique we used. In revision THA, we can revise the stem with the same length of previous one again and exchange also a long stem to a regular length stem. In addition, the system make it possible to re-construct the case of distal medullar canal excessively filled with bone cement below stem, by digging about around 2 cm distally without need to remove all the cement. Severe bone atrophy and fragile of femur is also reconstructed by IBG.

Impaction bone grafting technique with modified system has great merit to recover bone stock and to obtain implant stability after femoral reconstruction of revision surgery.

Visualization of the femoral medullar canal is troublesome in revision surgery. To obtain better visual field of the canal and assist cement extraction and following reconstructive procedures, flexible endoscope was applied in femoral revision. Mean age and time to revision of fifteen cemented totally replaced hips were 69.3 (42–83) and 14.9 (3–25) years, respectively. Preoperative status of the revision regarding type of stem loosening was classified as possible in four cases, probable in two, and definite in five classified by Harris et al. No marked finding of loosening was in four. That of bone defect was type I in four cases, Type II in three, and Type III in three by Gustilo. Five cases showed no marked loss of the defect. Extraction of cement mantle was performed under flexible endoscopic inspection. Impaction bone grafting was performed in eight cases. Time for cement removal in association with type of loosening and bone defect were evaluated as well as analysis of periprosthetic complications.

Retained cement mantle was extractable in all cases under good exposure and with maintenance of efficient working space. Interfacial granulation and fibrous tissues between bone and cement were easily removed. Endoscopic time for cement removal was 41.7 ± 10.3 minutes in average. It was 51.8 ± 6.2 minutes in no loosening. 41.3 ± 11.1 minutes in possible loosening, 38.5 ± 9.2 minutes in probable loosening, and 35.4 ± 8.3 minutes in definite loosening, which depended on the status of fixation between bone and cement. Type of bone defect also influenced the time. It was 52.4 ± 5.6 minutes in the cases of no marked bone loss, 43.8 ± 3.5 minutes in Gustilo type I, 28.3 ± 3.5 minutes in Type II, and 34.7 ± 2.5 minutes in Type III. The procedure was effective to prepare suitable bone bed for reconstruction, which allowed proper stem settlement and facilitated recovery of bone stock in the cases of impaction bone grafting. Intra-operative blood loss was 377 ml (212 – 1430) and total amount of blood loss including post surgical drainage was 593 ml (316 – 1680). Type of loosening and bone defect did not affect both whole and intra-operative bleeding volume. However, three occult fractures happened, in which two revealed minor cement leakage and one required additional osteosynthesis with extensive approach.

The data indicated that flexible medullo-endoscope could provide good visual field with maintenance of working space, potentially contributing to less invasive femoral revision surgery, if it would be combined with refined device for cement extraction to improve accuracy of the procedure.

Infection has been one of the serious complications after total hip arthroplasty. It forces physical and mental stress to the patients. We have routinely applied two-stage revision for infected replaced hip joint. Cement spacer mold technique has been used for the purpose since 2002. The purpose of this study is to analysis of peri-operative status and functional outcome of the patients underwent the two-stage revision procedure.

Nine joints of the eight patients were included in the study. Seven patients were female and one was male and its average age was 64 years (55–81 years). After removal of implant, antibiotic-loaded cement spacer prosthesis which was made by the cement spacer mold (Biomet, Warsaw, USA), was inserted. The leg length, range of motion of the hip, walking ability and complications between first and second-stage operation were analyzed. The change of leg length after first stage operation compared with prior operation was ranged from −18 mm to +13 mm with an average of 20 mm. Average range of hip flexion was 70°(40–90°). Patients could walk with crutches after first-stage operation. Complications after first stage operation were found in two cases; fracture of femoral cement spacer prosthesis and dislocation of the femoral spacer. There was no case of recurrence of infection.

Clinical assessment of two-stage revision for infected replaced hip joint with cement spacer mold showed favorable functional outcome and a few complications after first-stage operation. It also showed satisfactory short-term outcome after second-stage operation.