A Review of Total Hip Arthroplasty Comparison in FNF and OA Patients

Quality of cementing in hemiarthroplasty for elderly neck of femur fractures does not affect short term functional outcomes

INTRODUCTION

Cemented hip hemiarthroplasty is a routine surgical option for elderly neck of femur (NOF) fractures. It is uncertain if quality of cementing has any effect on functional outcomes. The aim of this study was to determine if the quality of cementing would affect short term functional outcomes in elderly neck of femur fractures.

MATERIALS AND METHODS

Retrospective analysis of 637 single-centre cemented hip hemiarthroplasties from 2014 to 2021 was performed. Each post-operative radiograph was double-read by 2 authors (1 resident and 1 fellowship trained surgeon) to determine quality of cementing via the Barrack grading. Disagreements were reviewed by a third reader. Cement grades were grouped as Optimal (Barrack grade A-B), or Suboptimal (Barrack grade C-D). Functional outcomes were compared using mobility (community- or home-ambulant), assistance required for mobility, and Modified Barthel Index (MBI). Surgical parameters were compared between the groups.

RESULTS

There were 429 Optimal and 208 Suboptimal cases of cementing performed. There was no difference in age, American Society of Anesthesiologists score, mobility, assistance required, and MBI score pre-operatively (p > 0.05). Patients in the "Suboptimal" cementing group had a higher Charlson Comorbidity Index (CCI) score (p < 0.001). At 1 year post-operation, there was no significant difference between "Optimal" and "Suboptimal" cementing with regards to the proportion of community ambulators (30.2% vs. 25.7%, p = 0.252), walking independence (independent walkers (19.8% vs.17.3%), independent walkers with aids (41.3%vs.42.1%), walker with caregiver assistance (29.2%vs.33.7%), wheelchair-bound (9.6%vs.6.9%), p = 0.478), and distribution of MBI score (81.1%vs.82.2% achieving MBI > 60, p = 0.767). There was no significant difference in the proportion of patients with postoperative delirium (7.9% vs. 5.8, p = 0.324) or 1-year mortality rates (3.5% vs. 2.9%, p = 0.685). Except for stem design (12.2% tapered vs 20.1% collared; p = 0.011), no other surgical parameters were significantly different. The kappa value for inter-reader agreement was "substantial" at 0.727 (95% CI 0.682-0.772) (p < 0.001).

CONCLUSION

Quality of cementing in cemented hip hemiarthroplasty for elderly NOF fractures does not affect the short-term functional outcomes. In low demand patients and patients at risk of BCIS, optimal cementing may not be necessary to achieve similar short-term functional outcomes. Further studies should be conducted to determine the effect of sub-optimal cementing on long-term functional outcomes.

Roles of inflammatory cell infiltrate in periprosthetic osteolysis

Classically, particle-induced periprosthetic osteolysis at the implant-bone interface has explained the aseptic loosening of joint replacement. This response is preceded by triggering both the innate and acquired immune response with subsequent activation of osteoclasts, the bone-resorbing cells. Although particle-induced periprosthetic osteolysis has been considered a foreign body chronic inflammation mediated by myelomonocytic-derived cells, current reports describe wide heterogeneous inflammatory cells infiltrating the periprosthetic tissues. This review aims to discuss the role of those non-myelomonocytic cells in periprosthetic tissues exposed to wear particles by showing original data. Specifically, we discuss the role of T cells (CD3+, CD4+, and CD8+) and B cells (CD20+) coexisting with CD68+/TRAP- multinucleated giant cells associated with both polyethylene and metallic particles infiltrating retrieved periprosthetic membranes. This review contributes valuable insight to support the complex cell and molecular mechanisms behind the aseptic loosening theories of orthopedic implants.

Targeted therapy for peri-prosthetic osteolysis using macrophage membrane-encapsulated human urine-derived stem cell extracellular vesicles

Aseptic loosening of the prosthesis is a severe complication after joint replacement. It is of great practical significance and social value to discover the prevention and treatment strategies for this condition. Exosomes from urine-derived stem cells (Exos) have great potential in promoting bone repair, reconstruction, and regulating bone metabolism. However, they are easily eliminated by macrophages and incapable of targeting the osteolysis zone. In this study, based on macrophage "homing" into periprosthetic osteolysis region and cell membrane encapsulating nanotechnology, exosomes from urine-derived stem cells were encapsulated with macrophage membrane (MM) to prevent periprosthetic osteolysis. We found that macrophage membrane encapsulated urine-derived stem cell-derived exosomes (MM-Exos) can be targeted delivery to the osteolysis zone and enhance the therapeutic effectiveness of Exos, which alleviated wear particles-induced calvarial osteolysis. Furthermore, MM-Exos could provide immunological camouflage and allow the Exos to avoid phagocytosis by macrophages and stimulate cellular uptake by bone marrow-derived stem cells (BMSCs). Therefore, we demonstrated the unique ability of the macrophage membrane as a targeted transport of exosomes from urine-derived stem cells for the prevention and treatment of periprosthetic osteolysis. These biomimetic nanoparticles provided a new therapeutic exosome delivery system for preventing wear particles-induced osteolysis. STATEMENT OF SIGNIFICANCE: Macrophage membrane encapsulated urine-derived stem cell-derived exosomes (MM-Exos) can be targeted delivery to the osteolysis zone and enhance the therapeutic effect of Exos on peri‑prosthetic osteolysis prevention. MM-Exos could allow the Exos to avoid phagocytosis by macrophages and promote the uptake of Exos by BMSCs.

Targeting regulation of stem cell exosomes: Exploring novel strategies for aseptic loosening of joint prosthesis

Periprosthetic osteolysis is a major long-term complication of total joint replacement. A series of biological reactions caused by the interaction of wear particles at the prosthesis bone interface and surrounding bone tissue cells after artificial joint replacement are vital reasons for aseptic loosening. Disorder of bone metabolism and aseptic inflammation induced by wear particles are involved in the occurrence and development of aseptic loosening of the prosthesis. Promoting osteogenesis and angiogenesis and mediating osteoclasts and inflammation may be beneficial in preventing the aseptic loosening of the prosthesis. Current research about the prevention and treatment of aseptic loosening of the prosthesis focuses on drug, gene, and stem cell therapy and has not yet achieved satisfactory clinical efficacy or has not been used in clinical practice. Exosomes are a kind of typical extracellular vehicle. In recent years, stem cell exosomes (Exos) have been widely used to regulate bone metabolism, block inflammation, and have broad application prospects in tissue repair and cell therapy.

Psychiatric Disorders and Genotoxicity Following Primary Metal on Polyethylene Total Hip Arthroplasty and Their Correlation to Cobalt/Chromium Levels

Introduction

Hip arthroplasty (HA) using implantable metal components is among the commonest orthopedic interventions. However, it can be followed by several complications following corrosion and the release of metal ions. Several studies proved that damaged genomic DNA may contribute to the pathophysiology of mental disorders.

Aim

The current work aims to evaluate the psychiatric disorders in metal on polyethylene hip arthroplasty (MOP-HA) patients and its correlation to cobalt/chromium (Co/Cr) levels and genotoxicity.

Methods

The work was a longitudinal follow-up study including 34 adults with unilateral primary MOP-HA meeting the inclusion and exclusion criteria. Preoperatively, 6, 12-months-postoperatively, patients were examined for cognitive impairment using mini-mental-state-examination (MMSE), depression using major-depressive-inventory (MDI), and blood samples were collected for estimation of Co/Cr, detection of genotoxicity by single-cell-gel-electrophoresis (comet assay) and serum 8-hydroxy-2'-deoxyguanosine (8-OHdG).

Results

Cognitive impairment was reported in 18.5% and 14.8% at 6-months, and 12-months postoperative, respectively. Depressive disorder was recorded in 22.2% at 6-months and 14.8% at 12-months postoperative. The marginal homogeneity tests proved a non-significant difference. There was a non-significant difference in preoperative, 6-months, 12-months postoperative MMSE, and MDI scores. There were significantly increased Co/Cr levels at 6-months postoperative. The levels decreased at 12-months postoperative, however, still significantly higher than preoperative values. There was a significant increase in serum 8-OHdG and the levels were positively correlated to cobalt levels at both 6 and 12-months-postoperative. There was a non-significant difference among preoperative, 6-months, and 12-months postoperative comet assay measurements.

Conclusion

From previous findings, we can conclude that will-functioning MOP hip arthroplasty can induce increased ion levels and positively correlated increase in biochemical markers of genotoxicity (8-OHdG).

Human umbilical cord mesenchymal stromal cells promotes the proliferation and osteogenic differentiation of autologous bone marrow stem cells by secreting exosomes

Fractures are frequently encountered diseases troubling the senior population, and the research on fracture repair and the exploration of effective treatment methods are of great significance. This study aimed to clarify the effect of human umbilical cord mesenchymal stromal cell-derived extracellular vesicles (hUMSC-EVs) on the proliferation and osteogenic differentiation of autologous bone marrow stem cells (ABMSCs). The two kinds of cells were co-cultured firstly, 5-Ethynyl-2'- deoxyuridine (EDU) staining and alizarin red staining were used to detect the proliferation and osteogenic differentiation of ABMSCs. The exosomes of hUMSCs were subsequently extracted to process ABMSCs to further test the effect on the cells. The EDU positive rate of ABMSCs and Collagen II expression were elevated, whereas the TdT-mediated dUTP nick end labeling (TUNEL) positive rate and Matrix Metallopeptidase 13 (MMP13) were markedly decreased after the co-culture of hUMSCs and ABMSCs using Transwell chamber assays. The results indicated that hUMSCs could increase the proliferation of ABMSCs, reduce apoptosis, and promote matrix metabolism. The hUMSCs exosomes were separated and added to ABMSCs. As the exosomes content increased, the proliferation of ABMSCs increased simultaneously, and ABMSCs apoptosis decreased. Meanwhile, ABMSCs that migrated to the submembrane increased compared with untreated ABMSCs. Western blot, qPCR and immunofluorescence results revealed that increased exosomes contents promoted the expression of ABMSCs anabolic-related indicators gradually, while decreased the expression of catabolism-related indicators gradually. The previously described results indicated that hUMSCs promoted the proliferation and osteogenic differentiation of ABMSCs by secreting exosomes.