Purpose

The purpose of this study was to elucidate kinematic change according to the implant's specific femoral rotation by using orthosensor (Verasense) implant with three degrees external rotation of femoral rotation rebuilt (Genesis-II) and traditional TKA implant without rebuilt of the femoral rotation (Anthem).

Introduction

Deformity of knee joint causes deviation of mechanical axis in the coronal plane, and the mechanical axis deviation also could adversely affect biomechanics of the ankle joint as well as the knee joint. Particularly, most of the patients undergoing total knee arthroplasty (TKA) have significant preoperative varus malalignment which would be corrected after TKA, the patients also may have significant changes of ankle joint characteristics after the surgery. This study aimed 1) to examine the prevalence of coexisting ankle osteoarthritis (OA) in the patients undergoing TKA due to varus knee OA and to determine whether the patients with coexisting ankle OA have more varus malalignment, and 2) to evaluate the changes of radiographic parameters for ankle joint before and 4 years after TKA.

Introduction

Even a number of studies have reported clinical outcomes after revision total knee arthroplasty (revision TKA), little information is still available on whether outcomes of patients undergoing a revision TKA as a second stage procedure because of infected TKA are poorer than those of the patients undergoing a single-stage revision TKA because of non-infectious causes. In addition, use of various revision prostheses in most previous studies may limit solid interpretation of the outcomes after revision TKA. This study sought to determine whether outcomes in patients undergoing revision TKA due to infected TKA would be different from those in patients undergoing revision TKA due to non-infectious causes.

Introduction

Total knee arthroplasty (TKA) is a proven treatment method for advanced knee arthritis in terms of pain relief, function restoration, and quality-of-life improvement. The TKA use has increased significantly over the past decade and the growing rate is more prominent in Asian countries. Thus, the revision TKA may also increase in recent days, which represents a burden to the national health care system. To the best of our knowledge, little information is currently available regarding the incidence and related factors of revision TKA in Asian countries on the basis of nationwide database. This study sought to find the incidence of revision TKA and related factors in South Korea using national database from 2007 to 2012.

In conventional high tibial osteotomy it is difficult to obtain the ideal correction angle consistently and there is high variability of postoperative alignment. We assessed the reliability, accuracy and variability of closed wedge high tibial osteotomy using computer-assisted surgery compared to the conventional technique. Fifty closed wedge HTO procedures were performed and analysed between July 2005 and July 2006, using the CT-free navigation system(Vector Vision^® version 1.1, Brain-LAB, Heimstetten, Germany) for medial compartment osteoarthritis of the knee and fifty knee operations using conventional closed-wedge HTO, performed between 1994 and 2006, were retrospectively reviewed as a control group. The mean age was 59.4 years for the navigation group and 60.7 years for the conventional group. In the navigation group, the mean mechanical axis (MA) before osteotomy was varus 8.2°, and the mean MA after the fixation was valgus 3.6°. On the radiographs, the mean preoperative MA was varus 7.3°, and the mean postoperative MA was valgus 2.1°. In the conventional group, the mean MA was varus 10.6° preoperatively and valgus 0.1° postoperatively via the radiograph. The mean preoperative posterior slope angle (PSA) was 11.0°, which decreased to 9.0° in the navigation group. The mean preoperative PSA was 10.4°, which decreased to 6.4° in the conventional group(p = 0.000). There was a positive correlation between measured data taken under navigation and by radiographs(r > 0.3, P < 0.05). The mean correction angle was significantly more accurate in the navigation group(p < 0.002). The variability of the correction was significantly lower in the navigation group (2.3° versus 3.7°, p = 0.012), and the distribution of MA was also narrower in the navigated group.

We concluded that navigation provides reliable real-time intraoperative information and may increase accuracy, and improve the precision of closed-wedge HTO.

The purpose of this study is to identify clinical and radiographic results of 78 uncemented total hip arthroplasties using Metasul^® metal on metal bearings with Wagner standard cup and proximal hydroxyapatite coated CLS stem.

Mean age was 39 years and average follow-up period was 11.7 years. Mean Harris hip score had improved from 51.4 points preoperatively to 95.2 points finally. There were 2 hips with progressive osteolysis around the acetabular cup. Of them, one hip was revised due to loosening of the cup, and the other was observed because of patient’s refusal to revise. In histopathologic findings on osteolytic area, a lot of macrophage phagocytizing metal debris and perivascular lymphocyte infiltration were found. Immunohistochemical analysis suggested delayed metal hypersensitivity. Serum cobalt levels in hips with osteolysis were not higher than those in hips without osteolysis.

Early osteolysis with sudden onset of groin pain in few hips remains a concern.

Introduction: This study evaluated the clinical and radiological outcomes of Chiari osteotomy for severe coxa irregularis and subluxation of the femoral head.

Materials and Methods: The study group included patients with late Legg-Calvé-Perthes disease (6 patients), posttraumatic avascular necrosis (1 patient), and multiple epiphyseal dysplasia (1 patient). The mean age at surgery was 11.4 years (range, 6.8 to 14.7). The clinical parameters evaluated included changes in pain, limp, and range of motion of the hip. Radiographic measurements were made to determine the width of the medial and superior joint spaces, acetabular coverage, lateral epiphyseal extrusion, and the Stulberg classification.

Results: At a mean follow-up of 5 years (range, 1.1 to 11.0 years), pain disappeared completely in 5 patients or markedly decreased, enough to complete normal daily physical activities, in the remaining 3 patients. Limping gait disappeared completely in 2 patients, but the remaining 6 patients had minimal limps. All the components of the range of hip motion increased significantly. Acetabular coverage averaged 55% (range, 33 to 87%) before operation and 88% (range, 79 to 97%) at the final follow-up. Lateral epiphyseal extrusion was 49% (range, 39 to 83%) before operation, and 18% (range, 8 to 40%) at the final follow-up. Joint spaces were not changed significantly after surgery.

Discussion: In conclusion, Chiari osteotomy has its own indications, as a salvage procedure, for older children and adolescents with subluxated, severe coxa irregularis. The current study confirms the efficacy of the operation in terms of the functional and radiological improvements.

Introduction: The authors introduce a modified technique of iliac splitting and expanding shelf (ISES) arthroplasty for severe LCPD, and report on the intermediate outcomes.

Materials and Methods: This new procedure is a modification of the previously reported tectoplasty of Saito (1986) and the shelf arthroplasty of Catterall (1992). Only the sartorius muscle and the indirect head of the rectus femoris muscle are detached, leaving the abductors intact. A superiorly hinged bony flap was raised from the lateral iliac wall just above the hip joint capsule. A corticocancellous bone plate was harvested from the inner table of the iliac wing, and was placed between the lateral hip joint capsule and the bony flap. The triangular space between the split iliac wall and the bone plate was packed with autogenous cancellous bone chips and Osteoset® (Wright-Medical, Arlington, Tennessee, USA). The repaired indirect head of the rectus femoris muscle gave stability to the shelf. After 4 weeks in a Petrie cast, the hip was mobilized, and partial weight bearing was started postoperative at 6 weeks. Twenty one hips in 21 children older than 8 years presenting with early (18 hips) and late (reossification) (3 hips) LCPD were treated by ISES arthroplasty. All patients were followed up for more than 2 years (range, 2 to 8.5 years).

Results: There were significant functional and radiological improvements after operation. One patient needed a secondary varus osteotomy to solve persistent subluxation. The poorest result occurred in a very obese child, presenting with early stage of Catterall IV involvement at age 11.5 years.

Discussion: Our modified technique of the shelf arthroplasty, sparing the abductor mechanism, appears to be a reliable and effective method to augment the superolateral coverage of the femoral head in severe LCPD.

Introduction: In severe Legg-Calve-Perthes (LCPD) disease with subluxated femoral head, the acetabulum sometimes takes a bicompartmental appearance. This study analyzed acetabular pathoanatomy using a 3-D CT program.

Materials and Methods: A 3-D CT software program that affords the section of 2-D image in any plane was used to analyze the acetabular pathoanatomy, with specific reference to the morphology of the inner surface of the acetabulum. Thirteen children with the bicompartmental acetabulae (12 LCPD and 1 AVN subsequent to septic hip arthritis) were evaluated.

Results: The anterior half of the acetabulum was concentric. The contour of the acetabular margin in the posterior half of the acetabulum consisted of two different arcs – an arc of the iliac acetabulum (superior) and the other arc of the acetabular fossa of the ischium (medial). The junction of these two arcs was located at the triradiate cartilage, which was increased in mediolateral thickness at this point. The osteochondral articular margin of the ischium posterior to the non-articular acetabular fossa was thickened forming a ridge. The mediolateral thickness of the non-articular acetabular fossa was thinner than that of the normal contralateral side. The combination of these focal morphologic changes of the acetabular fossa rendered the bicompartmental appearance on plain AP radiograph of the pelvis.

Discussion: The authors conclude that bicompartmentalization of the acetabulum apparently reflects the altered biomechanics of the hip joint due to the subluxated femoral head. The abnormal osteocartilaginous hypertrophy appears to be caused by synovial irritation and an eccentric molding effect of the subluxated femoral head.

The purpose of this study was to investigate the efficacy of oral alendronate for the older children with osteogenesis imperfecta. Eight boys and 6 girls with average age of 9.7 years were given oral alendronate, 10mg everyday for those > 35kg, 10mg every other day for those 20 – 35 kg, and 10mg every three days for those < 20 kg. Treatment period averaged 3.3 years (range, 2.1 to 3.6). The number of fractures decreased by 39% in the lower extremity, although not statistically significant. Ten patients or their parents reported improved well-being during the treatment period. Z score for bone mineral density improved from −3.75 to −1.18 in the lumbar spine, and from −3.84 to −2.74 in the femur neck. Restoration of the collapsed vertebral bodies was observed, and the metaphyseal bands appeared on the simple radiographs. Urinary excretion of calcium and N-telopeptide of type I collagen were decreased by 64% and 47%, respectively. Abdominal discomfort was reported in five patients, one of which needed temporary switch to intravenous protocol. Iliac crest biopsy including the physis showed expanded primary spongiosa area with numeric multi-nucleated cells, which had heterogenous immunoreactivity for osteoclast markers.

This study revealed beneficial effects of oral alendronate in osteogenesis imperfecta patients, supported by radiological, biochemical and histological findings. We believe that oral alendronate is a more convenient method of bisphosphonate treatment for osteogenesis imperfecta, especially in older children.