What is Anatomical Shoulder Replacement?

Anatomical shoulder replacement, also known as total shoulder arthroplasty (TSA), is a surgical procedure designed to replace the damaged parts of the shoulder joint with prosthetic components that mimic the joint’s natural anatomy. It is performed to relieve pain and restore function in patients suffering from severe shoulder conditions, such as arthritis or trauma.

This procedure is called “anatomical” because it maintains the natural alignment and mechanics of the shoulder by replicating the normal anatomy of the ball-and-socket joint.

Anatomy of the Shoulder Joint

The shoulder joint, also called the glenohumeral joint, is a ball-and-socket joint where:

• The humeral head (the ball) fits into the glenoid (the socket), which is part of the shoulder blade.
• The joint is stabilized by surrounding ligaments, muscles, and tendons, including the rotator cuff.

Why is Anatomical Shoulder Replacement Performed?

Anatomical shoulder replacement is recommended for patients with:

1. Severe Osteoarthritis: Wear and tear of the joint cartilage leading to bone-on-bone contact and pain.
2. Rheumatoid Arthritis: An autoimmune condition causing inflammation and joint destruction.
3. Post-Traumatic Arthritis: Damage from shoulder injuries, such as fractures or dislocations.
4. Avascular Necrosis: Death of bone tissue due to loss of blood supply.
5. Intact Rotator Cuff Tears

Patients typically experience:

• Chronic shoulder pain, often worsening with movement.
• Reduced range of motion.
• Weakness in the shoulder.

Procedure Overview

The surgery involves replacing the damaged ball and socket with prosthetic components:

• Humeral Head (Ball): Replaced with a metal implant.
• Glenoid (Socket): Replaced with a high-density polyethylene (plastic) component.

Steps of the Procedure:

1. Anesthesia: General or regional anesthesia is administered.
2. Incision: A surgical incision is made over the shoulder joint.
3. Bone Preparation: Damaged cartilage and bone are removed from the humeral head and glenoid.
4. Implantation:
   • The humeral head is replaced with a metal stem and spherical head.
   • The glenoid is resurfaced with a plastic prosthesis.
5. Closure: The incision is closed, and a bandage is applied.

The surgery typically takes 1-2 hours.

Benefits of Anatomical Shoulder Replacement

1. Pain Relief: Substantial reduction or elimination of chronic shoulder pain.
2. Improved Mobility: Restores the ability to perform daily activities like reaching and lifting.
3. Enhanced Quality of Life: Improved shoulder function for recreational and professional tasks.

Who is a Candidate?

Ideal candidates are those who:

• Have significant shoulder joint damage confirmed by imaging (e.g., X-rays or MRIs).
• Have failed conservative treatments like physical therapy, anti-inflammatory medications, or corticosteroid injections.
• Have intact rotator cuff tendons.

Recovery and Rehabilitation

Recovery from anatomical shoulder replacement involves:

Post-Surgery Care:

• Sling Use: To protect the shoulder and promote healing.
• Pain Management: Medications and ice packs to reduce discomfort.

Physical Therapy:

• Begins within days of surgery to restore range of motion and strength.
• Gradual progression to strengthening exercises over weeks and months.

Recovery Timeline:

• Most patients resume light activities within 6 weeks.
• Full recovery and return to high-demand activities may take 4-6 months.

Potential Risks and Complications

While generally safe, the procedure carries some risks, including:

• Infection at the surgical site.
• Loosening or Dislocation of the prosthetic components.
• Stiffness or Loss of Motion in the shoulder.
• Nerve or Blood Vessel Injury.

Anatomical Shoulder Replacement vs. Reverse Shoulder Replacement

Anatomical shoulder replacement differs from reverse shoulder replacement, which is used when the rotator cuff is severely damaged or non-functional. In reverse replacement, the positions of the ball and socket are reversed to rely on different muscles for movement, such as the deltoid.

Conclusion

Anatomical shoulder replacement is a highly effective surgical solution for individuals with severe shoulder joint damage and intact rotator cuff tendons. By restoring the natural anatomy of the shoulder, this procedure can significantly reduce pain, improve mobility, and enhance quality of life. Consulting with an orthopedic surgeon is essential to determine if this procedure is the right option based on your condition and lifestyle needs.