Introduction

A key outcome measured by national joint registries are revision events. This informs best practice and identifies poor-performing surgical devices. Although registry data often record reasons for revision arthroplasty, interpretation is limited by lack of standardised definitions of revision reasons and objective assessment of radiologic and laboratory parameters. Our study aim was to compare reasons for unicompartmental knee arthroplasty (UKA) revision reported to the New Zealand Joint Registry (NZJR) with reasons identified by independent clinical review.

Aims

Several artificial bone grafts have been developed but fail to achieve anticipated osteogenesis due to their insufficient neovascularization capacity and periosteum support. This study aimed to develop a vascularized bone-periosteum construct (VBPC) to provide better angiogenesis and osteogenesis for bone regeneration.

Prophylactic antibiotics are important in reducing the risk of periprosthetic joint infection (PJI) following total knee arthroplasty. Their effectiveness depends on the choice of antibiotic and the optimum timing of their administration, to ensure adequate tissue concentrations. Cephalosporins are typically used, but an increasing number of resistant organisms are causing PJI, leading to the additional use of vancomycin. There are difficulties, however, with the systemic administration of vancomycin including its optimal timing, due to the need for prolonged administration, and potential adverse reactions. Intraosseous regional administration distal to a tourniquet is an alternative and attractive mode of delivery due to the ease of obtaining intraosseous access. Many authors have reported the effectiveness of intraosseous prophylaxis in achieving higher concentrations of antibiotic in the tissues compared with intravenous administration, providing equal or enhanced prophylaxis while minimizing adverse effects. This annotation describes the technique of intraosseous administration of antibiotics and summarizes the relevant clinical literature to date.

Cite this article: Bone Joint J 2023;105-B(11):1135–1139.

Higher levels of socioeconomic deprivation have been associated with worse health outcomes. The influence of socioeconomic deprivation on patients undergoing periacetabular osteotomy (PAO) has not previously been investigated.

A total of 217 patients (171 female, 46 male; median age 23.4 years) who underwent PAO by a single surgeon were identified. Patients were categorised into three groups according to their New Zealand Deprivation (NZDep) Index: minimal deprivation (NZDep Index 1–3, n=89), moderate deprivation (NZDep Index 4–6, n=94), and maximal deprivation (NZDep Index 7–10, n=34). The three groups were compared with respect to baseline variables, surgical details, complications, and pre-operative and two-year post-operative functional scores (including International Hip Outcome Tool (iHOT-12), EQ-5D quality of life score, and University of California Los Angeles (UCLA) activity score). Multivariate regression was undertaken to assess for the effect of NZDep Index on patient outcomes.

Patients in the maximal deprivation group were more likely to be Māori (p<0.001) and have surgery in a public rather than a private hospital (p=0.004), while the minimal deprivation group demonstrated a lower BMI (p=0.005). There were otherwise no other significant differences in baseline variables, surgical details, complications, nor pre-operative or two-year post-operative functional scores between the three groups (all p>0.05). Multivariate analysis identified a higher NZDep Index to be independently predictive of a lower pre-operative UCLA activity score (p=0.014) and a higher two-year iHOT-12 score (p<0.001).

Our results demonstrate an inequality in access to PAO, with patients exposed to higher levels of socioeconomic deprivation under-represented in our study population. When provided access to PAO, these vulnerable patients achieve significant functional improvement at least as great as patients with less socioeconomic deprivation. Initiatives to improve access to hip preservation care in socioeconomically deprived populations appear warranted.

Aims

LY3023414 is a novel oral phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) dual inhibitor designed for advanced cancers, for which a phase II clinical study was completed in March 2020; however, little is known about its effect on bone modelling/remodelling. In this study, we aimed to explore the function of LY3023414 in bone modelling/remodelling.

Aims

The aim of this study was to systematically compare the safety and accuracy of robot-assisted (RA) technique with conventional freehand with/without fluoroscopy-assisted (CT) pedicle screw insertion for spine disease.

Aims

The aims of this study were to validate the outcome of total elbow arthroplasty (TEA) in patients with rheumatoid arthritis (RA), and to identify factors that affect the outcome.

Aims

The aim of this meta-analysis was to compare the outcome of total elbow arthroplasty (TEA) undertaken for rheumatoid arthritis (RA) with TEA performed for post-traumatic conditions with regard to implant failure, functional outcome, and perioperative complications.

The purpose of this study was to evaluate the functional and oncological outcome of recycled autograft reconstruction after a wide excision for primary malignant bone tumor around the hip.

From 1998 to 2015, 67 patients with a primary malignant bone tumor involving proximal femur or periacetabular zone (P2) were included. There were 36 males and 31 females with a mean age of 34 years (13 to 58). Of these, 29 patients had grade I or II chondrosarcoma, 28 high-grade osteosarcoma, 6 Ewing's sarcoma and 4 undifferentiated pleomorphic sarcoma. Enneking stage of all 67 patients was stage II. Of the resection classification, proximal femur resection was performed in 29 patients, P1+P2 in 15, P2+P3 in 14, P1+P2+P3 in 4, P2 only in 4, and P2+proximal femur in 1. Extracorporeally irradiated recycled autograft and liquid nitrogen frozen autograft were performed in 44 and 23 patients, respectively.

At a mean follow-up of 98 months (10 to 239), 48 patients (72%) were continuously disease-free, 12 (18%) died of disease and 7 (10%) were alive with disease. The tumors of these patients who had died of disease were usually located in pelvic bones (10/12). Of these 37 patients with pelvic tumors, 7 patients (22%) had local recurrence, four of them received external hemipelvectomy. Other complications included hip dislocation in 2 patients, nerve injury in 2 and deep infection in 2. However, the above complications were rarely occurred in the patients with proximal femur reconstruction. The mean Musculoskeletal Tumor Society functional score were 77% (53 to 93).

Recycled autograft reconstruction for primary malignant bone tumor around the hip is a valid method with acceptable morbidity and a favorable functional outcome.

Two-stage reconstruction with total implant removal and re-implantation after infection control is considered the gold standard treatment forinfection after hip arthroplasty. However, removal of the well-fixed stem or cup may cause substantial bone loss and other complications, thereby making reconstruction difficult. We evaluated whether an infection posttotal hip arthroplasty can be treated without removal of the radiographically and clinically well-fixed femoral stem or acetabular cup. Patients with a chronic infection aftertotal hip arthroplasty, with a radiographically well-fixed, cementless stem or cup, were selected. During the first surgical stage, we retained the stem or cup if we were unable to removethese with a stem or cup extractor. An antibiotic-impregnated cement spacer was then implanted. After control of infection (C-reactive proteinlevel within normal value), we performed the secondstage of re-implantation surgery. Treatment failure was defined as uncontrolled infection requiringremoval of the retained implant.

From January 2004 to December 2013, 16 patients underwent partial component-retained 2-stage reconstruction. Thirteen patients (81.3%) were free of infection, with a mean follow-up time of 5 years. The remaining 3 patients, who had high-risk comorbidities and, of whom, 2 were infected by high-virulence organism, had uncontrolled infection and required furthersurgery to remove the retained implant.

We conclude that partial component-retained 2-stage reconstruction could be an alternative treatment option for chronic infection afteran uncemented total hip arthroplasty with a radiographically and clinically well-fixed component in selected patients, who are notimmunocompromised and are infected by a low-virulence organism.

Introduction

Periprosthetic joint infection (PJI) and particle-induced osteolysis are closely related to peri-implant local immunity and macrophage function. We previously demonstrated that titanium particles attenuate the immune response of macrophages caused by chronic inflammation [1]. In a separate study, we have determined that UHMWPE wear particles containing vitamin E (VE) induce less osteolysis compared to HXL UHMWPE wear particles in a murine calvarium model [2]. For this study we hypothesized that macrophages exposed to HXL UHMWPE particles containing VE would better maintain their ability to respond to S. aureus compared to HXL UHMWPE without VE.

Objective

To investigate the biomechanical mechanism and report preliminary clinical efficacy of eccentric rotational acetabular osteotomy (ERAO) when conduct treatment for developmental dysplasia of the hip (DDH).

Objective

To investigate the biomechanical basis and report preliminary clinical efficacy of eccentric rotational acetabular osteotomy (ERAO) when treating developmental dysplasia of the hip (DDH).

Structural allografts may be used to manage uncontained bone defects in revision total knee replacement (TKR). However, the availability of cadaver grafts is limited in some areas of Asia. The aim of this study was to evaluate the mid-term outcome of the use of femoral head allografts for the reconstruction of uncontained defects in revision TKR, focusing on complications related to the graft.

We retrospectively reviewed 28 patients (30 TKRs) with Anderson Orthopaedic Research Institute (AORI) type 3 bone defects, who underwent revision using femoral head allografts and stemmed components. The mean number of femoral heads used was 1.7 (1 to 3). The allograft–host junctions were packed with cancellous autograft.

At a mean follow-up of 76 months (38 to 136) the mean American Knee Society knee score improved from 37.2 (17 to 60) pre-operatively to 90 (83 to 100) (p < 0.001). The mean function score improved from 26.5 (0 to 50) pre-operatively to 81 (60 to 100) (p < 0.001). All the grafts healed to the host bone. The mean time to healing of the graft was 6.6 months (4 to 16). There have been no complications of collapse of the graft, nonunion, infection or implant loosening. No revision surgery was required.

The use of femoral head allografts in conjunction with a stemmed component and autogenous bone graft in revision TKR in patients with uncontained bone defects resulted in a high rate of healing of the graft with minimal complications and a satisfactory outcome. Longer follow-up is needed to observe the evolution of the graft.

Cite this article: Bone Joint J 2013;95-B:643–8.

Tranexamic acid (TEA), an inhibitor of fibrinolysis, reduces blood loss after routine total knee replacement (TKR). However, controversy persists regarding the dosage and timing of administration of this drug during surgery. We performed a prospective randomised controlled study to examine the optimum blood-saving effect of TEA in minimally invasive TKR.

We randomly assigned 151 patients who underwent unilateral minimally invasive TKR to three groups: 1) a placebo group (50 patients); 2) a one-dose TEA group (52 patients), who received one injection of TEA (10 mg/kg) intra-operatively on deflation of the tourniquet; and 3) a two-dose TEA group (49 patients), who received two injections of TEA (10 mg/kg) given pre-operatively and intra-operatively. Total blood loss was calculated from the maximum loss of haemoglobin. All patients were followed clinically for the presence of venous thromboembolism (VTE).

The mean total blood loss was significantly higher in the placebo group than in the other two groups (1222 ml (845 to 2043) versus 1035 ml (397 to 1934) and 986 ml (542 to 1811), respectively (both p < 0.0001)). The mean blood loss was not significantly different between the one- and two-TEA groups (p = 0.148). The mean transfusion rate was higher in the placebo group than in the other two groups (22% versus 3.8% (p = 0.006) and 6.1% (p = 0.041), respectively) and there was no statistically significant difference in the mean transfusion rate between the one- and two-TEA groups (p = 0.672). Only one patient, in the two-dose group, had a radiologically confirmed deep venous thrombosis.

Our prospective randomised controlled study showed that one intra-operative injection of TEA is effective for blood conservation after minimally invasive TKR.

Routinely in TKA, at least one of the cruciate ligaments are sacrificed. The cruciate ligaments excision may have an impact in the stability of the reconstructed knee by virtue of the impact on the gap kinematics. In this study, a selective cutting protocol was designed to quantify the individual contribution of ACL and PCL about the knee by means of a loaded cadaveric model.

Five fresh frozen normal cadaver specimens were used. The femur was fixed to a specially designed machine, and 3D tibial movements relative to the femur and joint gap distances were measured by means of a navigation system from full extension to 140° flexion. The joint was distracted with 10 pounds. The measurement was performed before and after ACL and PCL excision.

Medial gap distance at 90° flexion before and after cruciate ligaments excision was 4.3 ± 2.7 mm (mean ± SD) and 5.1 ± 2.8 mm (p< 0.05) respectively. Cruciate ligaments excision significantly widened the medial and lateral gaps at many flexion angles, and the effect of excision on the gap distance was different between medial and lateral sides especially at 90° knee flexion. Cruciate ligaments excision also significantly influenced knee kinematics. If this varying gap is not accounted for either through implant shape and orientation or through soft tissue adjustments, instability could be the result.

Surgeons should be made aware of the influence of cruciate excision on varus/valgus laxity throughout the range of motion. Design modification of the femoral component may also be necessary in order to obtain optimal stability in deep flexion.

High-pressure injection injuries occur infrequently but are usually work-related and involve the non-dominant hand. The neck is a very rare site for such an injury. We describe the management of a 36-year-old man with a high-pressure grease-gun injection injury to his neck causing a cervical spinal cord injury. He developed severe motor and sensory changes which were relieved by surgical removal of the grease through anterior and posterior approaches.

We evaluated the long-term outcome of patients with an osteosarcoma who had undergone prior manipulative therapy, a popular treatment in Asia, and investigated its effects on several prognostic factors. Of the 134 patients in this study, 70 (52%) patients had manipulative therapy and 64 (48%) did not. The age, location, and size of tumour were not significantly different between the groups. The five-year overall survival rate was 58% and 92% in the groups with and without manipulative therapy (p = 0.004). Both the primary and overall rates of lung metastasis were significantly higher in the manipulative group (primary: 32% vs 3%, p = 0.003; overall lung metastasis rate: 51.4% vs 18.8%, p < 0.001). Patients who had manipulative therapy had higher local recurrence rates in comparison to patients who did not (29% vs 6%, p = 0.011). The prognosis for patients with osteosarcoma who had manipulative therapy was significantly poorer than those who had not. Manipulative therapy was an independent factor for survival.

This form of therapy may serve as a mechanism to accelerate the spread of tumour cells, and therefore must be avoided in order to improve the outcome for patients with an osteosarcoma.

Intra-articular resection of bone with soft-tissue balancing and total knee replacement (TKR) has been described for the treatment of patients with severe osteoarthritis of the knee associated with an ipsilateral malunited femoral fracture. However, the extent to which deformity in the sagittal plane can be corrected has not been addressed. We treated 12 patients with severe arthritis of the knee and an extra-articular malunion of the femur by TKR with intra-articular resection of bone and soft-tissue balancing. The femora had a mean varus deformity of 16° (8° to 23°) in the coronal plane. There were seven recurvatum deformities with a mean angulation of 11° (6° to 15°) and five antecurvatum deformities with a mean angulation of 12° (6° to 15°).

The mean follow-up was 93 months (30 to 155). The median Knee Society knee and function scores improved from 18.7 (0 to 49) and 24.5 (10 to 50) points pre-operatively to 93 (83 to 100) and 90 (70 to 100) points at the time of the last follow-up, respectively. The mean mechanical axis of the knee improved from 22.6° of varus (15° to 27° pre-operatively to 1.5° of varus (3° of varus to 2° of valgus) at the last follow-up. The recurvatum deformities improved from a mean of 11° (6° to 15°) pre-operatively to 3° (0° to 6°) at the last follow-up. The antecurvatum deformities in the sagittal plane improved from a mean of 12° (6° to 16°) pre-operatively to 4.4° (0° to 8°) at the last follow-up.

Apart from varus deformities, TKR with intra-articular bone resection effectively corrected the extra-articular deformity of the femur in the presence of antecurvatum of up to 16° and recurvatum of up to 15°.

Posterior stabilized (PS) type knee prosthesis characterized by Post-Cam structure as stabilizer has successfully been used in TKA worldwide, while failure and fracture problems of tibial insert made from polymeric material (UHMNWPE) are still important issues from clinical and mechanical points of view. It is therefore needed to understand the mechanical conditions of the tibial insert under different kinds of TKA motions. The aim of this study is to characterize the mechanical condition of tibial insert under contact between femoral component and tibia insert during flexional motion using dynamic 3-D finite element (FE) method. 3-D FE models of two different kinds of PS type prostheses clinically used were developed and stress analyses were performed from full extension to 135 degree knee flexion. Effects of the different Post-Cam structures on the stress states were investigated, and a guideline towards risk assessment of PS type prosthesis was discussed.

Three-D FE models of Stryker’s PS type knee prostheses, Scorpio Superflex and NRG, were developed base on their CAD data. The tibial post of Scorpio Superflex type knee prosthesis shapes angular, while NRG shapes round. Four nodes tetrahedral elements were used to construct the FE models. Nonlinear spring models were attached to the front and back of the tibial component to express the effect of soft tissues on the movement of real TKA knees. Vertical load and horizontal load were applied to the femoral and tibial components, respectively, to express a deep knee bending (squatting) motion. Flexion motion was introduced by rotation the femoral component from full extension to 135 degree. Internal rotation of 5, 10, 15 degrees were also introduced by rotating the tibial component simultaneously with the flexional motion.

Maximum Mises equivalent stress during knee flexion with 5, 10 and 15 degrees internal rotation of the tibial component of Superflex were much higher than that of NRG, especially at the flexion angle of 120 degree. NRG exhibited stress concentrations on both the Post and condylar surfaces and stress levels were much lower that that of Superflex. The maximum stress in NRG was found to be reduced to about half of Superflex. Mises equivalent stress distribution also showed that flexion with internal rotation generated higher stress concentrations on the condylar surfaces of both prostheses.

The analytical results well demonstrated that the design modification of the tibial insert of NRG effectively reduced the stress concentration with rotated tibial component. The lower stress level in NRG corresponds to the lower reaction force and hence lower resistance to flexional motion than Superflex. This implies that the round post is more suitable for deep flexion than the angular post.