Augmented baseplates in reverse shoulder arthroplasty: a systematic review of outcomes and complications

Development, Evolution, and Outcomes of More Anatomical Reverse Shoulder Arthroplasty

Reverse shoulder arthroplasty (RSA) has become a widely used procedure since its introduction in the 1980s, and is currently used to treat a wider range of conditions than its original indication. The original Grammont-style RSA revolutionized shoulder arthroplasty but had several limitations, including scapular notching and reduced rotational motion. This review discusses the evolution of RSA design, particularly the development of a lateralized center of rotation constructs, which aims to improve all the disadvantages associated with the Grammont-style design and more closely reproduce the native anatomy in order to improve patient outcomes in an expanded context of pathologies.

IGF2BP1 Bolsters the Chondrocytes Ferroptosis of Osteoarthritis by Targeting m6A/MMP3 Axis

Introduction

Chondrocyte degeneration and senescence are characteristics of osteoarthritis (OA) and other joint degenerative diseases, and ferroptosis has been observed to regulate the development of OA. However, the role of the N6-methyladenosine (m6A) modification in OA ferroptosis remains unclear.

Methods

This study performed series of assays to investigate the function of the m6A reader IGF2BP1 in OA ferroptosis, including m6A quantitative analysis, Iron (Fe2+) release analysis, Malondialdehyde (MDA) measurement, lipid peroxidation (ROS) detection and Glutathione (GSH) measurement. The molecular interaction and mechanism analysis was performed by Luciferase reporter assay, mRNA stability analysis and RNA immunoprecipitation (RIP) assay.

Results

These results indicate that IGF2BP1 is upregulated in IL-1β-induced chondrocytes. Functionally, IGF2BP1 silencing represses ferroptosis, including iron (Fe2+) accumulation, malondialdehyde, and reactive oxygen species (ROS). Mechanistically, among the potential downstream targets, matrix metalloproteinase-3 (MMP3) was observed to harbor a significant m6A modified site in the 3'-UTR. IGF2BP1 combines with MMP3 through the binding of m6A sites, thereby enhancing MMP3 mRNA stability.

Discussion

In conclusion, our findings revealed the functions and mechanisms of m6A regulator IGF2BP1 in OA chondrocyte's ferroptosis, providing a novel target for OA treatment.

Glenoid bone loss in shoulder arthroplasty: a narrative review

Background and Objective

Crucial to the success of any total or reverse shoulder arthroplasty (RSA) is the stability of the glenoid component fixation. Instability can lead to early implant failure and unsatisfactory results. Patients often present with varying forms of glenoid bone loss (GBL) in both the primary and revision settings, which can be a challenge for the treating surgeon. Severe cases of GBL can increase the risk of potential complications and diminish implant longevity. The use of the reverse total shoulder replacement has been particularly helpful when addressing significant glenoid bony defects. Various approaches have been proposed to deal with GBL, all of which require an individualized assessment of the specifics of the defect in order to provide maximal fixation and thereby optimize the longevity of the shoulder arthroplasty. This article aims to review the recent literature on GBL in shoulder arthroplasty to provide guidance when considering treatment based on the best available evidence.

Methods

PubMed, MEDLINE, EMBASE, AccessMedicine, ClinicalKey, DynaMed, and Micromedex were queried for publications utilizing the following keywords: "glenoid bone loss" AND "glenoid bone deficiency" AND "shoulder arthroplasty" AND "classification". The search was restricted to research published between 2004 and 2023. There were no restrictions on study type or language.

Key Content and Findings

GBL should be critically evaluated prior to undertaking total shoulder arthroplasty (TSA). The treating surgeon should be aware of various methods of addressing bone defects.

Conclusions

The use of TSA is increasing to address various shoulder pathologies. Addressing glenoid bone defects is of critical importance to maximize the longevity and outcome of TSA.

Narrative review of influence of prosthesis lateralization on clinical outcomes in reverse shoulder arthroplasty: glenoid vs. humerus vs. combined

Background and Objective

Reverse shoulder arthroplasty has become a common orthopaedic procedure, with a growing number of cases annually for multiple indications, such as rotator cuff arthropathy, osteoarthritis, or fractures of the proximal humerus, to reduce pain and restore shoulder mobility. Prosthesis design and various recent improvements aim to enhance range of motion (ROM) and stability and to limit component loosening and other potential complications. Many of these well-known issues could theoretically be improved by glenoid, humeral, or combined component lateralization. The objective of this article is to provide an up-to-date literature overview, present available options, and discuss the rationale behind lateralization of certain components, as well as their combined impact on outcomes of reverse shoulder arthroplasty.

Methods

PubMed and Scopus databases from 2003 to 2023 were searched and screened for studies, including systematic reviews, on the influence of glenoid, humeral, and combined component lateralization that served for narrative review of rationale behind such design.

Key Content and Findings

Currently, a number of computer simulations, anatomic studies, and limited clinical references aim to support the rationale behind glenoid augmentation, variable humeral neck-shaft angle (NSA), or humeral tray design.

Conclusions

The utility of lateralization has not yet been clinically established. Randomized, long-term clinical outcome studies are still needed to reach a verdict going beyond surgeon preference and case-specific indications.