Shoulder Hemiarthroplasty

Shoulder hemiarthroplasty (HA) is a surgical treatment used for complex fractures of the upper part of the arm bone (proximal humerus), especially when traditional bone fixation isn’t suitable. In this procedure, the damaged part of the shoulder joint is replaced with a prosthetic implant, while the socket (glenoid) is left intact.

This technique has long been considered the gold standard, particularly for older adults with fractures that cannot be reliably stabilized with plates and screws. However, with the advent of reverse shoulder arthroplasty (RSA), the indications for hemiarthroplasty are being reconsidered.

What Is Shoulder Hemiarthroplasty?

Shoulder hemiarthroplasty replaces the upper part of the arm bone (humeral head) with a metal implant. It’s primarily indicated for:

• Comminuted (multiple-fragment) fractures of the proximal humerus.
• Fractures where the blood supply to the bone is compromised, risking bone death (osteonecrosis).
• Cases where anatomical realignment (open reduction and internal fixation, or ORIF) is unlikely to succeed.

HA does not involve replacing the shoulder socket (glenoid), which distinguishes it from total or reverse shoulder replacements.

Who Are Ideal Candidates?

According to the study by Valenti et al., ideal candidates are typically:

• Older than 60 years
• Have complex 3-part or 4-part fractures
• Have reasonably intact rotator cuff tendons
• Cannot undergo successful fixation with plates and screws

Younger patients with healthy rotator cuffs may also be considered when ORIF isn’t viable.

The Surgical Technique: Step by Step

1. Positioning and Approach: The patient is placed in a beach-chair position under general anesthesia with a nerve block for pain relief. A deltopectoral incision gives the surgeon access to the shoulder joint.
2. Tendon Management: The long head of the biceps is detached and anchored (tenodesis) to reduce future pain. Tuberosities—the greater and lesser bony prominences where shoulder tendons attach—are carefully prepared for reconstruction.
3. Implant Placement:
   • The damaged humeral head is removed.
   • A special guide is used to determine the correct height and angle (retroversion) of the implant.
   • Bone grafts from the removed humeral head are used to aid tuberosity healing.
   • The stem of the prosthesis is cemented into place.
4. Tuberosity Fixation: A “lasso” suture technique secures the tuberosities around the implant to restore tendon function and promote healing. This is a critical step, as improper healing of the tuberosities can lead to poor outcomes.
5. Closure and Immobilization: After thorough irrigation, the wound is closed and the arm is placed in a sling with slight abduction.
6. Rehabilitation: Passive movement begins after 4 weeks, with active-assisted exercises introduced around 2 months.

Outcomes and Satisfaction

• 75% of patients were satisfied with their outcomes.
• Mean forward flexion was 98°, and external rotation was 22°.
• Pain scores significantly influenced patient satisfaction more than range of motion.
• Healing of the tuberosities was observed in 74.5% of cases.
• Four patients required revision surgery, including conversion to reverse shoulder arthroplasty.

Patients reported satisfaction levels as follows:

• Excellent: 26%
• Good: 43%
• Acceptable: 6%
• Poor: 25%

Complications and Risks

Common complications after shoulder hemiarthroplasty include:

• Tuberosity nonunion or malunion: Failure of the bone fragments to heal properly can impair shoulder function.
• Component malpositioning: Incorrect placement of the implant can result in instability or impingement.
• Rotator cuff failure: If the cuff is weak or torn, the shoulder may not regain full function.
• Persistent pain: Sometimes, even if the bone heals, patients experience discomfort due to joint wear or soft tissue issues.
• Cuff failure occurred in 47% of cases.
• Tuberosity issues were present in over 40%.
• Glenoid erosion developed in over 30%—especially when the implant was misaligned or the shoulder was imbalanced.

Comparing Hemiarthroplasty with Reverse Shoulder Arthroplasty

While hemiarthroplasty preserves the native socket and rotator cuff, reverse shoulder arthroplasty (RSA) replaces both the ball and socket and changes the mechanics to rely on the deltoid muscle instead of the rotator cuff. This makes RSA more predictable in patients with:

• Poor bone quality
• Torn or dysfunctional rotator cuffs
• Failed previous surgeries

 

Key Takeaways

• HA is still a viable option, particularly in younger or active elderly patients with intact rotator cuffs and complex fractures.
• Success relies heavily on tuberosity healing, proper implant placement, and post-op rehab.
• Patient satisfaction is more influenced by pain relief than absolute function.
• In select cases, RSA may be preferred due to its independence from rotator cuff healing.

Final Thoughts

Shoulder hemiarthroplasty remains an effective treatment for selected patients with complex proximal humerus fractures. A detailed surgical technique and carefully planned rehabilitation protocol are essential to maximize outcomes. However, patients and surgeons must weigh the benefits against newer techniques like reverse shoulder replacement, especially in cases with cuff deficiency or advanced age.

 

Do you have more questions?

Q. What is shoulder hemiarthroplasty?
A. Shoulder hemiarthroplasty is a surgical procedure where only the head of the humerus (upper arm bone) is replaced with an artificial implant, leaving the natural socket (glenoid) intact.

Q. When is shoulder hemiarthroplasty recommended?
A. It is recommended when there is damage to the humeral head but the glenoid is still in good condition, such as in certain fractures or cases of arthritis affecting only the humeral head.

Q. What conditions can be treated with shoulder hemiarthroplasty?
A. Conditions include severe fractures of the humeral head, avascular necrosis, and certain cases of osteoarthritis or rheumatoid arthritis where the glenoid is unaffected.

Q. What are the advantages of shoulder hemiarthroplasty?
A. Advantages include preservation of the natural glenoid, less bone removal, and potentially shorter surgery time and recovery.

Q. How is shoulder hemiarthroplasty different from total shoulder replacement?
A. In shoulder hemiarthroplasty, only the humeral head is replaced, whereas in total shoulder replacement both the humeral head and the glenoid are replaced with prosthetic components.

Q. What is the typical recovery process after shoulder hemiarthroplasty?
A. Recovery involves immobilization in a sling followed by physical therapy to restore range of motion and strength over several weeks to months.

Q. What type of anesthesia is used for shoulder hemiarthroplasty?
A. General anesthesia or a regional nerve block is typically used during the procedure.

Q. How long does shoulder hemiarthroplasty surgery take?
A. The procedure usually takes about one to two hours.

Q. What are the risks of shoulder hemiarthroplasty?
A. Risks include infection, nerve injury, prosthesis loosening, stiffness, and continued pain.

Q. Can patients return to normal activities after shoulder hemiarthroplasty?
A. Most patients can return to daily activities and low-impact sports after rehabilitation, but some limitations may remain.

Q. How long does the implant last after shoulder hemiarthroplasty?
A. Implants can last many years, but longevity depends on activity level, bone quality, and other patient-specific factors.

Q. Is physical therapy necessary after shoulder hemiarthroplasty?
A. Yes, physical therapy is essential for regaining shoulder motion, strength, and function after surgery.

Q. Who is not a good candidate for shoulder hemiarthroplasty?
A. Patients with glenoid damage, severe rotator cuff tears, or poor bone quality may not be ideal candidates for this procedure.