Courtesy: Prof William Levine, Past President, ASES

Historical Evolution of Shoulder Arthroplasty

Professor Levine outlined six innovation eras.

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Era 1: Early Shoulder Arthroplasty (Late 1800s–1950s)

• Themistocles Gluck (Germany)

  • First shoulder arthroplasty

  • Modular ivory prosthesis

  • Not widely recognized at the time

• Jules Péan (France)

  • First documented shoulder replacement (1893)

  • Two-stage procedure

  • Ultimately failed due to infection

• Early 20th century:

  • Limited options

  • Humeral head resection or arthrodesis for fractures

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Era 2: Neer Era (1950s–1990s)

• Dr. Charles Neer

  • Introduced humeral head replacement for fractures

  • Developed Neer I and Neer II systems

  • Transitioned to total shoulder arthroplasty

Impact:

• Disruptive innovation

• TSA shown superior to hemiarthroplasty in:

  • Patient outcomes

  • Durability

  • Satisfaction

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Era 3: Grammont Era – Reverse Shoulder Arthroplasty

• Paul Grammont (1985)

  • Medialized center of rotation

  • Semiconstrained design

  • Increased deltoid lever arm

  • Enabled treatment of pseudoparalytic shoulders

Benefits:

• Allowed treatment of cuff tear arthropathy

• Reliable stability

Limitations:

• Scapular notching

• Osteolysis

• Poor external rotation

• Humeral bone loss

• Shoulder contour changes

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Era 4: Lateralization Improvements

• Mark Frankle

  • Lateralized center of rotation

  • Improved rotation

  • Reduced scapular notching

Resulted in modern RSA systems.

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Era 5: Convertible and Stemless Systems

Convertible Stems

Purpose:

• Allow conversion from anatomic TSA to RSA without stem removal.

However:

• Literature shows up to 42–49% of “convertible” stems still require revision.

• Stem removal increases:

  • Blood loss

  • Surgical time

  • Complication rates

True Convertible Concept

• Stem positioned below osteotomy level

• Allows easier conversion to reverse

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Era 6: Technology Integration

1. Preoperative Planning

• 100% CT-based planning

• Virtual templating

• Important in training settings

2. Custom Implants

• Used for severe deformity or bone loss

• Patient-specific instrumentation

3. Intraoperative Navigation

• Real-time execution of surgical plan

• Improves precision

4. Robotics

• Highly accurate

• Clinical superiority not yet proven

• Workflow integration still evolving

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Pyrocarbon Hemiarthroplasty

• Reduced wear properties

• Some promising short-term results

Concerns:

• Glenoid erosion (23%)

• Implant position changes

• ~8% revision rate at 2 years

Conclusion:

• Likely similar limitations as traditional hemiarthroplasty

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Is Anatomic TSA Obsolete?

Professor Levine argues:

“Do not throw away the anatomic total shoulder.”

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Long-Term Strengths of Anatomic TSA

• Excellent long-term outcomes

• Superior patient-reported satisfaction compared to RSA

• Better motion in well-selected patients

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Major Concerns

1. Glenoid loosening

2. Subscapularis failure

3. Rotator cuff deterioration

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Glenoid Loosening

Large registry data (35,000+ procedures):

• Glenoid loosening = 26% of failures

• Rotator cuff insufficiency = 17%

• Instability and infection also significant

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Hybrid Glenoid Design

Modern solution:

• Cemented peripheral pegs

• Trabecular metal central peg (bone ingrowth)

Results:

• 1–2% failure rate at 10 years

• Markedly improved durability

Professor Levine considers hybrid glenoid the current gold standard.

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Vitamin E-Enhanced Polyethylene

Benefits:

• Reduces oxidation

• Improves wear resistance

• Maintains mechanical strength

• Reduced osteolysis

Adopted in modern systems.

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Indications: Anatomic vs Reverse

Reverse Shoulder Arthroplasty

Strong Indications:

• Cuff tear arthropathy

• Pseudoparalysis

• Elderly 3- or 4-part proximal humerus fractures

Concerns:

• Increasing complications

• Re-revision rate nearly 30%

• Overall complication rate ~33% in revision RSA

Not benign when it fails.

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Anatomic TSA Preferred When:

• Centered humeral head

• Intact and functional rotator cuff

• Adequate glenoid vault

• Good subscapularis quality

Professor Levine’s current practice:

• ~55–60% anatomic TSA

• ~40–45% reverse

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Concerns About Overuse of Reverse

• Some surgeons perform 100% RSA

• Trainees may not even see anatomic TSA

• Potential future epidemic of reverse complications

Comparison made to decline of open Bankart procedures in instability surgery.

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Training and Virtual Reality

• VR training (e.g., Precision OS) can supplement cadaver training

• Promising educational tool

• Not yet a full replacement

• Future vision: AI-driven real-time guidance without CT scans

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Key Takeaways

• Shoulder arthroplasty has evolved through six major innovation eras.

• Reverse arthroplasty is transformative but not complication-free.

• Anatomic TSA remains superior in well-selected cuff-intact patients.

• Hybrid glenoid designs significantly reduce loosening.

• Vitamin E polyethylene improves implant longevity.

• Overuse of reverse arthroplasty may create future revision challenges.

• Young surgeons must maintain expertise in anatomic TSA.

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Final Message

Anatomic total shoulder arthroplasty is not extinct.

It remains:

• A powerful procedure

• Biomechanically sound

• Often superior when properly indicated

Careful patient selection and understanding of implant evolution remain essential.