[Shoulder arthroplasty in rheumatoid arthritis]

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Rheumatology

Background:

• Shoulder arthroplasty offers long-term survival comparable to hip arthroplasty, approximately 85% at 15 years.
• Rheumatoid arthritis is a critical factor influencing shoulder arthroplasty outcomes, surpassing rotator cuff integrity and surgical approach (hemiarthroplasty vs. total arthroplasty).
• Osteoarthritis and rheumatoid arthritis present distinct glenoid wear patterns: medial erosion with cranial migration in osteoarthritis versus rotator cuff compromise in rheumatoid arthritis.

Purpose of the Study:

• To compare the long-term survival and functional outcomes of various shoulder arthroplasty procedures.
• To identify key predictive factors for successful shoulder arthroplasty outcomes, particularly in patients with rheumatoid arthritis.
• To delineate the specific challenges and optimal surgical strategies for shoulder arthroplasty in different patient populations and disease pathologies.

Main Methods:

• Comparative analysis of long-term survival rates for shoulder arthroplasties.
• Evaluation of functional results based on implant type (hemiarthroplasty, total arthroplasty, surface replacement, reverse arthroplasty, bipolar implants).
• Assessment of the influence of preoperative diagnosis (rheumatoid arthritis, osteoarthritis) and rotator cuff status on surgical outcomes and revision rates.

Main Results:

• Total shoulder replacements demonstrate slightly better functional results than hemiarthroplasties.
• Rheumatoid arthritis patients experience adverse effects from poor rotator cuff quality, leading to secondary cranial migration and potential glenoid loosening, though revision rates remain low (under 5%).
• Glenoid erosion is more common and problematic in rheumatoid arthritis hemiarthroplasty patients compared to osteoarthritis, often requiring revision.

Conclusions:

• Total shoulder arthroplasty is preferred for shoulders with intact or moderately worn rotator cuffs and good coronal alignment.
• Humeral head surface replacement offers comparable results to conventional hemiarthroplasty, with glenoid combination yielding superior outcomes.
• Reverse arthroplasty is indicated for elderly patients with severe rotator cuff destruction, while younger patients may benefit from bipolar implants to avoid metaglenoid loosening.