Periprosthetic hip fractures (PPFs) after total hip arthroplasty are difficult to treat. Therefore, it is important to identify modifiable risk factors such as stem selection to reduce the occurrence of PPFs. This study aimed to clarify differences in fracture torque, surface strain, and fracture type analysis between three different types of cemented stems. We conducted biomechanical testing of bone analogues using six cemented stems of three different types: collarless polished tapered (CPT) stem, Versys Advocate (Versys) stem, and Charnley-Marcel-Kerboull (CMK) stem. Experienced surgeons implanted each of these types of stems into six bone analogues, and the analogues were compressed and internally rotated until failure. Torque to fracture and fracture type were recorded. We also measured surface strain distribution using triaxial rosettes.Aims
Methods
We compared the clinical outcomes of curved intertrochanteric varus osteotomy (CVO) with bone impaction grafting (BIG) with CVO alone for the treatment of osteonecrosis of the femoral head (ONFH). This retrospective comparative study included 81 patients with ONFH; 37 patients (40 hips) underwent CVO with BIG (BIG group) and 44 patients (47 hips) underwent CVO alone (CVO group). Patients in the BIG group were followed-up for a mean of 12.2 years (10.0 to 16.5). Patients in the CVO group were followed-up for a mean of 14.5 years (10.0 to 21.0). Assessment parameters included the Harris Hip Score (HHS), Oxford Hip Score (OHS), Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ), complication rates, and survival rates, with conversion to total hip arthroplasty (THA) and radiological failure as the endpoints.Aims
Methods
There are few reports including natural course of initial gap in total hip arthroplasty. The purpose of this study is to investigate the incidence of initial gap in the PSL type shells and its natural course. Total of 386 THAs with Trident or TriAD PSL shells were performed between January 2000 and December 2014. Exclusion criteria were shells with screw fixations (n=189), previous pelvic osteotomy (n=15) and less than 3 years’ follow-up (n=11). Finally, our study included 171 hips. Average age was 56.8 (17∼83) years at THA and average follow-up time was 8.3 (3∼16.3) years; 112 (66%) were women; and 120 hips (70.2%) had osteoarthrosis. As radiographic evaluation, we checked presence or absence of initial gap, maximum size of it, gap filling and cup stability. The presence of initial gap was defined as gap present on post-operative anteroposterior X-ray measuring 1mm or greater. Gap filling was defined as confirmed trabecular formation between the cup and acetabular floor without cup migration. And we determined the time to gap filling. As clinical evaluation, we retrospectively checked Harris Hip Score (HHS) at pre-operative and final follow-up period, and presence of shell revision. Furthermore, we compared clinical results with or without initial gap.Background
Methods
Acetabular component loosening has been one of the factors of revision of total hip arthroplasty (THA). Inadequate mechanical fixation or load transfer may contribute to this loosening process. Several reports showed the load transfer in the acetabulum by metal components. However, there is no report about the influence of the joint surface on the load transfer. We developed a novel acetabular cross-linked polyethylene (CLPE) liner with graft biocompatible phospholipid polymer(MPC) on the surface. The MPC polymer surface had high lubricity and low friction. We hypothesized the acetabular component with MPC polymer surface (MPC-CLPE) may reduce load transfer in the acetabulum compared to that of the by CLPE acetabular component without MPC. We fixed the three cement cup with MPC-CLPE (Group M; sample No.1–3) and three cement cup with CLPE (Group C; sample No.4–6) placed in the synthetic bone block with bone cement with a 0.10mm thick arc-shaped piezoresistive force sensor, which can measure the dynamic load transfer(Tekscan K-scan 4400; Boston). (Fig 1) A hip simulator (MTS Systems Corp., Eden Prairie, MN) was used for the load transfer test performed according to the ISO Standard 14242-1. Both groups had same inner and outer diameter s of 28 and 50mm, respectively. A Co–Cr alloy femoral head with a diameter of 28 mm (K-MAXs HH-02; KYOCERA Medical Corp.) was used as the femoral component. A biaxial rocking motion was applied to the head/cup interface via an offset bearing assembly with an inclined angle of +20. Both the loading and motion were synchronized at 1 Hz. According to the double-peaked Paul-type physiologic hip load, the applied peak loads were 1793 and 2744 N described in a previous study. The simulator was run 3 cycles. We recorded both the peak of the contact force and the accumulation of the six times load in total. Secondly, we calculated the mean change of the load transfer. We used the Student t-test. P value < 0.05 was used to determine statistical significance. We used EZR for statistical analysis.Introduction
Methods
It has been reported that the tibial articular surface of coronal aligment is parallel to the floor in the whole-leg standing radiographs of the normal knee. The purposes of this study are to investigate the relationship between the tibial articular surface and the ground on the whole-leg standing radiographs after total knee arthroplasty(TKA). 20 knees after TKA were studied retrospectively. The 20 participants were mean age at 76.7 years; and 3 male and 17 female. Using whole-leg standing radiographs, we mesuared the pre- and postoperative hip-knee- ankle angle(HKA), the tibial joint line angle(TJLA), and the tibial component Coronal tibial angle(CTA). The difference in each parameter was compared and examined.Introduction
Sturdy Design and Methods
The influence of identifiable pre-operative factors on the outcome
of eccentric rotational acetabular osteotomy (ERAO) is unknown.
We aimed to determine the factors that might influence the outcome,
in order to develop a scoring system for predicting the prognosis
for patients undergoing this procedure. We reviewed 700 consecutive ERAOs in 54 men and 646 women with
symptomatic acetabular dysplasia or early onset osteoarthritis (OA)
of the hip, which were undertaken between September 1989 and March
2013. The patients’ pre-operative background, clinical and radiological
findings were examined retrospectively. Multivariate Cox regression
analysis was performed using the time from the day of surgery to
a conversion to total hip arthroplasty (THA) as an endpoint. A risk
score was calculated to predict the prognosis for conversion to
THA, and its predictive capacity was investigated.Aims
Patients and Methods
One-stage bilateral total hip arthroplasty (THA) is twice as invasive as unilateral THA. Therefore, increases in bleeding, postoperative anemia, and complications are a concern. The purpose of this study was to investigate hemoglobin values and the use of autologous and allogenic blood transfusion after one-stage bilateral THA. Twenty-nine patients (7 men and 22 women; 58 hips) were treated with one-stage bilateral THA. The mean age of subjects at the time of surgery was 60.6 years. The average body mass index for patients was 21.7 kg/m2. The diagnoses were secondary osteoarthritis due to developmental dysplasia of the hip (n=25) and avascular necrosis (n=4). All patients had donated 800 ml of autologous blood in 2 stages preoperatively (1 to 4 weeks apart). All patients took iron supplements starting from 5 weeks preoperatively. For all patients, the procedure was performed under general anesthesia in the lateral decubitus position via a posterolateral approach. Intra-operative blood salvage was not used. Suction drains were inserted subfascially. As a general rule, pre-donated autologous blood was transfused back to the patients intra- or post-operatively. Allogenic blood transfusion was performed when clinical symptoms of anemia occurred (hypotension, low urinary output, tachycardia, etc.) rather than using a preset blood threshold (hemoglobin level <8 g/dl). To determine changes in blood pressure following surgery until the next morning, systolic and diastolic blood pressure were measured at 3-hr intervals.Background
Methods
A transtrochanteric curved varus osteotomy (TCVO) is an excellent joint preserving surgical modality if the necrotic lesion can be moved to the non-weight bearing area as assessed by maximum abduction antero-posterior radiographs. The purpose of this article was to elucidate whether TCVO can reduce the volume of osteonecrosis after an index osteotomy as assessed by magnetic resonance imaging (MRI). Twenty patients (twenty hips) with non-traumatic osteonecrosis of the femoral head were followed for more than three years after an index operation and MRI examinations both before and at two years after surgery were retrospectively investigated. The average age at the time of operation was 40 years (range, 18 to 60 years), consisting of 13 men (13 hips) and 7 women (7 hips). The etiology and/or associated risk factors was steroid-associated osteonecrosis in 11 hips, alcohol associated in 7 hips, and idiopathic in 2. According to the classification of the Japanese Investigation Committee there was Type B in one hip, Type C-1 in 17 hips, and Type C-2 in 2 hips. Eight hips were in Stage 2, 10 in Stage 3A, and 2 in Stage 3B. Average follow-up was 4 years (range, 3 to 5 years).Introduction
Methods
The purpose of this study was to investigate the long-term outcome of Sugioka's transtrochanteric rotational osteotomy (TRO) for nontraumatic osteonecrosis of the femoral head. Seventy-eight patients (87 hips) were consecutively treated by TRO from 1989 to 1994. All patients followed 15 years or more were included. Four patients (4 hips) with traumatic osteonecrosis and five patients (5 hips) followed less than 15 years were excluded. A total of 69 patients (78 hips) were included. Average age at the time of operation was 42 years. There were 51 men (57 hips) and 18 women (21 hips). The average follow-up was 17 years (range, 15 to 20 years). Type of osteonecrosis was as follows: Type B; 2 hips, Type C1; 50 hips, and Type C2; 26 hips. Stage was as follows: stage 2; 29 hips, stage 3A; 34 hips, stage 3B; 13 hips, and stage 4; 2 hips. Transtrochanteric anterior rotational osteotomy was performed in 76 hips and posterior rotational osteotomy was performed in 2 hips. Clinical evaluation was evaluated by Harris hip score. Kaplan-Meier survivorship analysis was performed based on the end point of conversion to total hip arthroplasty (THA) or re-collapse.Introduction
Methods
Our purpose is to use radiographs to compare callus formation with two types of intramedullary nailing for femoral shaft fractures: reamed interlocking (IL) and Ender nails. Femoral shaft type A fractures according to AO classification were studied. From 1991 to 1995, 27 patients with 27 fractures were treated with reamed IL nailing and 79 patients with 81 fractures were treated with Ender nailing. IL group included with an average of 22 (range, 16–28) years, and the Ender group included with an average of 28 (range, 15–72) years. Patients had been followed for an average of 1.8 (range, 1–2.8) years after surgery. In all cases of IL group, the femoral canal was reamed. For type A3 fractures, an interlocking screw was inserted only at the distal site. For type A1 and A2 fractures, both proximal and distal locking screws were placed. In the Ender nailing cases, 3 to 5 Ender nails were inserted from medial or lateral side of the supracondylar or intertrochanteric regions of the femur as was dictated by the fracture site. All of these fractures were reduced by a closed technique. The measurement of postoperative callus area was calculated from the maximum cross-sectional area on the anteroposterior and lateral radiographs. Fracture healing was successful in all patients. On the radiograph, the callus for the IL group appeared at a mean of 3.9 weeks after surgery, and at a mean of 2.8 weeks for the Ender group. In the IL and Ender groups, fracture healing was noted at a mean of 3.4 and 2.0 months, respectively. The mean area of callus formation in the IL and Ender nailing was 439.5mm2 and 699.4 mm2, respectively. To compare the two groups by using a Mann-Whitney U test, the significant differences were seen in the callus appearance period (p<
0.05) and in the callus area (p<
0.01). Dynamization at the fracture site is reported to increase external callus formation. Our results indicate that the elasticity of the fixation obtained with Ender nailing promotes callus formation.
