Shoulder Arthrodesis

Shoulder joint fusion, also known as shoulder arthrodesis, is a surgical procedure that fuses the bones of the shoulder joint into a single, solid unit. This eliminates movement at the glenohumeral joint but can significantly reduce pain and provide stability, especially when other treatments, like shoulder replacement, are not suitable.

How Common It Is and Who Gets It? (Epidemiology)

Shoulder fusion is less common than shoulder replacement but remains an important treatment option for certain patients, particularly when joint replacement is not possible. It is often considered for patients with severe arthritis, rotator cuff failure, trauma, or other conditions where the shoulder joint cannot be replaced. Patients with high-level spinal cord injuries, muscle paralysis, or advanced rheumatoid arthritis may also benefit from shoulder fusion, where mobility is less important than pain relief and stability.

Why It Happens – Causes (Etiology and Pathophysiology)

Shoulder fusion is typically considered when other treatment options have failed. The procedure is often indicated in cases such as:

Infection in the joint: Chronic infections that cause pain and deformity may make fusion the preferred option, especially if infections persist despite treatment.
Paralysis from childhood: Conditions such as brachial plexus injury or polio lead to shoulder paralysis. Fusion can stabilize the shoulder when muscle transfers aren’t feasible.
Deltoid and rotator cuff paralysis: In individuals with paralysis of both muscles, there may be insufficient power to support joint replacement, making fusion a better option.
Brachial plexus injury: After trauma, if some muscles remain functional, fusion can provide stability and aid in arm movement.
Advanced rheumatoid arthritis: For patients with rotator cuff destruction and instability, fusion offers pain relief and function where joint replacement is not an option.
Failed shoulder replacement: When a prosthetic shoulder fails, fusion may be required, particularly due to infection or severe bone loss.
Recurrent dislocations: For patients with frequent shoulder dislocations despite previous surgeries, fusion offers permanent joint stability.
After tumor surgery: If part of the humerus is removed due to cancer, fusion may restore strength and stability.
Severe rotator cuff tears: When multiple repairs have failed and muscle function is lost, fusion may be necessary.
Immunocompromised patients: Those on immunosuppressive treatments may have a higher risk of infection after joint replacement, making fusion a safer choice.
Tuberculosis of the shoulder: Although rare today, fusion can still be necessary in cases of resistant tuberculosis.

How the Body Part Normally Works? (Relevant Anatomy)

The shoulder joint consists of the humeral head (the ball) and the glenoid (the socket). The joint is stabilized by ligaments and muscles, including the deltoid and rotator cuff muscles, which help with shoulder movement. Fusion eliminates motion at the glenohumeral joint, fixing the humerus to the scapula and providing stability to the arm.

What You Might Feel – Symptoms (Clinical Presentation)

Patients who may benefit from shoulder fusion typically experience:

Chronic pain in the shoulder joint, especially during movement
Severe instability or recurrent dislocations
Loss of function or difficulty with tasks such as overhead lifting
Deformity or joint changes caused by arthritis or previous surgeries
Increased difficulty with activities like lifting, pushing, or reaching overhead

How Doctors Find the Problem? (Diagnosis and Imaging)

Diagnosis begins with a physical exam to assess the shoulder joint’s stability, strength, and range of motion. X-rays, CT scans, and MRIs are used to evaluate the severity of arthritis, joint instability, muscle function, and bone quality. Electromyography (EMG) and nerve conduction studies can also help assess nerve involvement and muscle function.

Procedure Types or Techniques (Classification)

Several surgical techniques are available for shoulder fusion:

Intra-articular Fusion: Fusion inside the joint using screws to fix the bones together.
Extra-articular Fusion: Fusion performed outside the joint.
Combined Techniques: A combination of internal and external elements, used for added strength, especially in children.

Screws, plates, and bone grafts are used to hold the bones together during healing. Special plates like pelvic reconstruction plates may be used in some cases, which mold to the shoulder and do not require removal later.

Treatment Options

Shoulder fusion is considered when other treatments, like joint replacement, are not viable. The goal is to provide pain relief and stability in cases of severe instability or when the shoulder joint is no longer functional. After fusion, the shoulder will no longer move, but the arm remains stable for functional tasks.

Recovery and What to Expect After Surgery

Recovery from shoulder fusion involves several stages:

Initial Recovery: The shoulder is immobilized in a sling for 3 to 6 weeks.
Physical Therapy: After the initial healing period, physical therapy begins to regain strength and mobility in the remaining parts of the arm.
Full Recovery: It can take several months for the fusion to heal completely. Full recovery time varies depending on the patient’s condition, bone quality, and adherence to rehabilitation.

Possible Risks or Side Effects (Complications)

Shoulder fusion has several potential risks, including:

Functional Limits: The fused shoulder cannot perform overhead tasks such as painting or climbing.
Nonunion (Pseudarthrosis): The bones may fail to fuse, occurring in 5–20% of cases.
Malposition: Incorrect alignment during surgery can affect shoulder function.
Distal Joint Stiffness: The wrist or elbow may become stiff due to reduced use.
Fractures: The humerus may fracture in 10–15% of cases due to stress.
AC Joint Dislocation: May occur if the acromioclavicular joint is already arthritic.
Nerve Irritation: Excess abduction may stretch nerves and cause pain.
Infection: Occurs in 3–5% of cases.
Hardware Migration: Pins or screws may shift if not properly secured.
Epiphyseal Damage in Children: Fusion performed before bone maturity may stunt growth.
Allograft Complications: If donor bone is used, infection or rejection risks increase.

Long-Term Outlook (Prognosis)

The long-term outlook for shoulder fusion is generally positive for patients with the appropriate indications. Fusion reduces pain and provides stability, allowing the patient to perform daily tasks that do not require overhead movement. However, the loss of joint mobility may impact activities requiring overhead motions. The outcome depends on the patient’s condition, surgical technique, and post-operative rehabilitation.

Out-of-Pocket Cost

Medicare

CPT Code 23800 – Shoulder Arthrodesis (Surgical Fusion of the Shoulder Joint): $243.92

Medicare Part B typically covers 80% of the approved cost for this procedure once your annual deductible has been met, leaving you responsible for the remaining 20%. Supplemental Insurance plans such as Medigap, AARP, or Blue Cross Blue Shield usually cover the remaining 20%, significantly reducing or eliminating out-of-pocket expenses for Medicare-approved surgeries. These plans coordinate with Medicare to fill the coverage gap and reduce financial responsibility.

If you have Secondary Insurance, such as TRICARE, an Employer-Based Plan, or Veterans Health Administration coverage, it acts as a secondary payer. These plans generally cover any remaining balance, including coinsurance or small deductibles, which typically range from $100 to $300, depending on your plan and provider network.

Workers’ Compensation

If your shoulder arthrodesis is required due to a work-related injury, Workers’ Compensation will cover all associated medical expenses, including surgery, rehabilitation, and follow-up care. You will not have any out-of-pocket expenses, as the employer’s insurance carrier directly covers all approved treatments.

No-Fault Insurance

If your shoulder surgery is needed due to an automobile accident, No-Fault Insurance will typically cover the full cost of treatment, including surgery and postoperative care. The only potential out-of-pocket cost may be a small deductible or co-payment depending on your policy.

Example

William Davis required shoulder arthrodesis (CPT 23800) due to chronic shoulder instability. His estimated Medicare out-of-pocket cost was $243.92. Since William had supplemental insurance through AARP Medigap, his remaining balance was fully covered, leaving him with no out-of-pocket expenses for the procedure.

Frequently Asked Questions (FAQ)

Q. What is shoulder arthrodesis?
A. Shoulder arthrodesis is a surgical procedure that fuses the bones of the shoulder joint to relieve pain and provide stability when other treatments have failed.

Q. When is shoulder arthrodesis recommended?
A. It is recommended for patients with severe shoulder dysfunction due to paralysis, infection, trauma, or failed previous surgeries where joint replacement is not suitable.

Q. What are the goals of shoulder arthrodesis?
A. The main goals are to relieve pain and stabilize the shoulder to allow for some functional use of the arm.

Q. What conditions can lead to the need for shoulder arthrodesis?
A. Conditions include brachial plexus palsy, chronic infection, flail shoulder, deltoid or rotator cuff paralysis, and failed shoulder replacement.

Q. Can shoulder arthrodesis restore normal shoulder motion?
A. No, shoulder arthrodesis eliminates motion at the shoulder joint but may allow for functional use of the arm through movement at the scapula and elbow.

Q. What type of anesthesia is used for shoulder arthrodesis?
A. General anesthesia is typically used during the procedure.

Q. What surgical approach is used in shoulder arthrodesis?
A. The procedure is usually done through an open surgical approach using an incision on the shoulder.

Q. How is the shoulder fused during arthrodesis?
A. The surgeon prepares the bone surfaces and uses hardware such as plates and screws to hold the bones together until they fuse.

Q. What position is the shoulder fused in?
A. The shoulder is typically fused in a functional position that balances stability with usable range, often at around 30 degrees of flexion, 30 degrees of abduction, and 30 degrees of internal rotation.

Q. How long does it take for the shoulder to fuse after arthrodesis?
A. Bone fusion can take several weeks to months, depending on individual healing.

Q. What is the recovery process after shoulder arthrodesis?
A. Recovery includes immobilization with a brace or cast followed by physical therapy to maximize function of the elbow, wrist, and hand.

Q. Are there risks associated with shoulder arthrodesis?
A. Yes, risks include infection, nonunion, malunion, nerve injury, hardware failure, and continued pain.

Q. What is nonunion in the context of shoulder arthrodesis?
A. Nonunion refers to the failure of the bones to fuse properly after surgery.

Q. Can shoulder arthrodesis be reversed?
A. No, it is a permanent procedure intended to provide long-term stability and pain relief.

Q. Is shoulder arthrodesis common?
A. It is not commonly performed and is usually reserved for cases where other treatments are not viable.

Summary and Takeaway

Shoulder fusion is an effective surgical solution for patients with severe shoulder instability or joint dysfunction where joint replacement is not an option. While it eliminates joint movement, it provides lasting pain relief and stability, enabling patients to perform everyday tasks that do not require overhead motion. Consulting with an orthopedic surgeon will help determine if shoulder fusion is the best choice for your condition.

Clinical Insight & Recent Findings

A recent study highlighted that shoulder joint fusion, or arthrodesis, remains an essential option for patients who cannot undergo shoulder replacement due to infection, paralysis, severe arthritis, or failed prosthetic surgery. By permanently fusing the humerus to the scapula, the procedure provides pain relief and joint stability when motion preservation is no longer possible.

Patients often regain functional use of the arm for daily tasks such as eating and dressing, though overhead motion is lost. The operation is particularly valuable for those with brachial plexus injuries or rotator cuff paralysis, where restoring strength and stability is more important than flexibility.

Despite potential risks such as nonunion, nerve irritation, or stiffness in nearby joints, modern fixation techniques and careful angle positioning have significantly improved outcomes and patient satisfaction. (“Study on shoulder arthrodesis – see PubMed.”)

Who Performs This Surgery? (Specialists and Team Involved)

Shoulder fusion surgery is performed by orthopedic surgeons specializing in joint reconstruction and upper extremity surgery. The surgical team may also include anesthesiologists, physical therapists, and nursing staff to assist with preoperative planning, anesthesia, and postoperative care.

When to See a Specialist?

If you are experiencing severe shoulder pain, instability, or loss of function that interferes with daily activities, consult an orthopedic specialist for an evaluation to discuss whether shoulder fusion might be the right option for you.

When to Go to the Emergency Room?

Seek immediate care if you experience signs of infection (fever, redness, warmth at the surgical site), significant pain that doesn’t improve with medication, or unusual numbness or tingling in your arm.

What Recovery Really Looks Like?

Recovery after shoulder fusion involves several phases. Initially, you will wear a sling, followed by physical therapy to regain strength and mobility in the remaining joints. Full recovery may take 4 to 6 months, depending on the severity of the fusion and the patient’s adherence to rehabilitation.

What Happens If You Delay Surgery?

Delaying shoulder fusion can lead to worsening symptoms, including increased pain, instability, and difficulty with everyday activities. Early intervention typically leads to better outcomes.

How to Prevent Recurrence or Failure?

To prevent recurrence or failure of the fusion, it’s important to follow your surgeon’s recommendations, adhere to a rehabilitation program, and avoid activities that place excess strain on the shoulder joint.

Nutrition and Bone or Joint Health

A balanced diet rich in calcium and vitamin D will support bone healing and long-term joint health. Discuss any necessary supplements with your healthcare provider.

Activity and Lifestyle Modifications

After surgery, you’ll gradually return to normal activities. However, you should avoid heavy lifting or overhead motions until fully cleared by your surgeon. Regular exercise and a healthy lifestyle will help maintain shoulder health and prevent further injury.