What is the recommended treatment for an older adult patient with significant subchondral degenerative changes at the glenoid cavity, severe glenohumeral arthritis, and limited mobility, who has tried conservative management and other surgical options without achieving satisfactory results?

Reverse Shoulder Arthroplasty for Significant Glenoid Degenerative Changes

Primary Recommendation

Reverse shoulder arthroplasty (RSA) is NOT the standard first-line surgical treatment for significant subchondral degenerative changes at the glenoid cavity in patients with intact rotator cuffs—anatomic total shoulder arthroplasty (TSA) remains the preferred option according to AAOS guidelines. 1

However, RSA represents a viable alternative in specific clinical scenarios, particularly when posterior glenoid deficiency or severe bone loss is present. 2, 3

Critical Decision Algorithm

Step 1: Assess Rotator Cuff Integrity

• If irreparable rotator cuff tear is present: RSA is mandatory; TSA is contraindicated per AAOS consensus recommendation 4, 5
• If rotator cuff is intact: Proceed to glenoid morphology assessment 1

Step 2: Evaluate Glenoid Morphology

• Standard concentric glenoid wear: TSA is preferred over hemiarthroplasty (Grade B recommendation, Level II evidence) 1
• Walch B2/B3 glenoids with posterior deficiency: Both TSA and RSA are reasonable options 3, 6
  • TSA with eccentric reaming or augmented components yields comparable outcomes to RSA at mid-term follow-up 6
  • RSA demonstrated lower postoperative pain scores (0.5 vs 1.2 on VAS, p=0.036) and fewer glenoid radiolucencies compared to TSA 3
  • Both achieve similar rates of minimal clinically important difference (95% TSA vs 98% RSA) 3

Step 3: Consider Patient Age

• Patients under 50 years: Exercise caution with any arthroplasty due to increased risk of prosthetic loosening and decreased survivorship 1, 5
• Older adults with failed conservative management: Proceed with arthroplasty selection based on rotator cuff status and glenoid morphology 5

Evidence Supporting RSA in Specific Scenarios

Posterior Glenoid Deficiency

• RSA for primary glenohumeral osteoarthritis with posterior glenoid deficiency (B1, B2, B3, or C glenoid) and humeral subluxation resulted in excellent outcomes at minimum 5-year follow-up 2
• Mean Constant score improved from 30 to 68 points (p<0.001) with significant improvements in pain, function, and range of motion 2
• Scapular notching occurred in 43% of cases but had no influence on clinical outcomes 2

Comparative Outcomes: TSA vs RSA for B2/B3 Glenoids

• Range of motion improvements: RSA showed 64.7° improvement in flexion vs 50.1° for TSA; 68.9° improvement in abduction vs 58.5° for TSA 6
• Internal rotation: TSA preserves better internal rotation compared to RSA (postoperative score 6.5 vs 5.2, p<0.001) 3
• Complication rates: Pooled complication rate 6% for RSA vs 9% for TSA; revision rate 1% for RSA vs 2% for TSA at mid-term follow-up 6
• Glenoid loosening: TSA had 29 cases with glenoid radiolucencies including 3 grossly loose components, while RSA had only 2 baseplate loosening cases 3

Bone Grafting Considerations

• Structural bone grafting with RSA effectively restores glenoid anatomy, bone stock, and true glenohumeral joint line in cases of significant glenoid defects 7
• Glenoid bone graft healed in all cases, though partial inferior lysis occurred in 50% without affecting clinical outcomes 2
• Bone grafting allows lateralization of baseplate and glenosphere, reducing severe scapular notching risk 7
• All patients demonstrated graft incorporation at 3-month follow-up on CT scan 7

Critical Contraindications and Pitfalls

Absolute Requirements Before Surgery

• Conservative management must be attempted and failed before surgical intervention 5, 8
• Essential preoperative imaging must assess glenoid morphology, bone loss, retroversion, bone quality, and rotator cuff integrity 5

Surgeon Selection

• Choose a surgeon performing at least 2 shoulder arthroplasties per year to reduce immediate postoperative complications and length of stay (Grade C recommendation) 1, 5

Perioperative Management

• Mandatory mechanical and/or chemical VTE prophylaxis for all shoulder arthroplasty patients per AAOS consensus recommendation 1, 5

Key Clinical Caveat

The question specifically asks about "significant subchondral degenerative changes at the glenoid cavity" without mentioning rotator cuff status. If the rotator cuff is intact, anatomic TSA remains the AAOS-recommended standard treatment (Grade B) 1. RSA should be reserved for cases with irreparable rotator cuff tears, severe posterior glenoid deficiency with subluxation, or when TSA is contraindicated 4, 5, 2. The presence of degenerative changes alone does not automatically indicate RSA over TSA.