Trapezius Muscle Transfer

The trapezius muscle transfer is an advanced surgical procedure used to restore shoulder motion and strength when key shoulder muscles or nerves are damaged. By rerouting a portion of the trapezius muscle—normally responsible for moving the shoulder blade—surgeons can recreate the lost ability to lift (abduction) or rotate (external rotation) the arm. This procedure offers new hope for patients who cannot undergo standard repairs or replacements.

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

Trapezius muscle transfer is a relatively uncommon but increasingly recognized procedure for patients with severe shoulder dysfunction caused by nerve injuries or irreparable muscle tears. It is most often performed in younger, active patients who have experienced a brachial plexus injury or a massive rotator cuff tear that cannot be repaired. It is also considered in patients who wish to avoid joint fusion or shoulder replacement surgery.

Why It Happens – Causes (Etiology and Pathophysiology)

In conditions such as brachial plexus injury or massive rotator cuff tear, the shoulder muscles responsible for lifting and rotating the arm—such as the deltoid, supraspinatus, and infraspinatus—may lose their function. This results in profound weakness, poor range of motion, and sometimes an inability to raise the arm. When nerve repair or tendon reconstruction fails, transferring another functioning muscle, like the trapezius, can restore the lost shoulder motion.

How the Body Part Normally Works? (Relevant Anatomy)

The trapezius is a large triangular muscle extending from the skull and neck down to the upper spine and shoulder blade (scapula). It stabilizes and moves the scapula during shoulder motion. The rotator cuff muscles—supraspinatus, infraspinatus, subscapularis, and teres minor—normally lift and rotate the arm while keeping the humeral head centered in the socket. When these muscles fail, the trapezius can be repositioned to mimic their action and restore partial shoulder mechanics.

What You Might Feel – Symptoms (Clinical Presentation)

Candidates for trapezius transfer typically experience:

• Inability to lift the arm or rotate it outward
• Shoulder drooping or instability
• Weakness despite prior repair attempts
• Loss of shoulder contour or muscle mass
• Difficulty performing daily activities like dressing, reaching, or grooming

How Doctors Find the Problem? (Diagnosis and Imaging)

Diagnosis begins with a detailed physical examination and imaging studies such as MRI or ultrasound to assess muscle integrity. Electromyography (EMG) tests can evaluate nerve damage and muscle activation. Surgeons will also test passive range of motion to ensure that the shoulder joint can still move freely—an essential requirement before considering a transfer.

Procedure Types or Techniques (Classification)

Several surgical variations exist, each tailored to the patient’s specific needs and underlying problem:

• Direct Lower Trapezius Transfer:
  The lower portion of the trapezius muscle is detached from the scapula and reattached near the infraspinatus or rotator cuff tendons to restore external rotation.
• Graft-Augmented Transfer:
  When the trapezius cannot reach its new attachment site, a tendon graft (such as an Achilles tendon allograft or semitendinosus autograft) is used to bridge the gap and connect the muscle to the humeral head.
• Modified Trapezius Transfer:
  The trapezius is transferred along with a small bone fragment from its original attachment, and a folded fascia lata graft from the thigh is added for length. The muscle is anchored near the deltoid insertion to improve arm lifting.

Other Problems That Can Feel Similar (Differential Diagnosis)

Conditions that can mimic the loss of shoulder motion include:

• Isolated rotator cuff tears (repairable)
• Frozen shoulder (adhesive capsulitis)
• Axillary nerve injury
• Deltoid or pectoralis major weakness
• Glenohumeral arthritis

A thorough evaluation helps distinguish candidates who will benefit from trapezius transfer from those who may need other interventions.

Treatment Options

When nerve or tendon repair is not feasible, trapezius transfer provides an alternative to restore shoulder movement. The procedure can be performed alone or combined with other reconstructive techniques. Unlike joint replacement or fusion, it maintains shoulder motion and is often favored in younger, more active patients.

Recovery and What to Expect After Surgery

Recovery from trapezius transfer requires careful protection and structured rehabilitation:

• Immobilization: The arm is placed in a brace or cast at approximately 130° of abduction for the first four weeks.
• Early Movement: Hand and elbow motion begin immediately; gentle isometric activation of the trapezius starts within the first week.
• Weeks 4–6: The arm is gradually lowered to a normal position, and light shoulder exercises begin.
• Months 2–6: Strengthening and range-of-motion exercises progress under physical therapy supervision.

Full recovery can take 6–12 months, depending on the severity of the original injury and rehabilitation progress.

Possible Risks or Side Effects (Complications)

Although outcomes are generally positive, potential risks include:

• Injury to the spinal accessory nerve (which powers the trapezius)
• Graft failure or stretching in graft-augmented cases
• Donor site pain or weakness when tissue is harvested from the thigh
• Muscle fatigue or strain if over-tensioned
• Persistent stiffness or limited range of motion

Long-Term Outlook (Prognosis)

Most patients experience significant improvement in shoulder motion and stability. Clinical studies show:

• Shoulder abduction improved from 37° to over 110° in patients with brachial plexus injury.
• External rotation improved by more than 30°, restoring the ability to reach and perform daily activities.
• For irreparable rotator cuff tears, average gains included 37.5° in forward elevation and 34.3° in external rotation.
  Patients typically report enhanced quality of life, reduced pain, and restored independence in activities of daily living.

Out-of-Pocket Costs

Medicare

CPT Code 23395 – Trapezius Muscle Transfer (Surgical Transfer of Trapezius or Latissimus Muscle to Restore Shoulder Function): $304.12

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 generally cover that remaining 20%, minimizing or eliminating out-of-pocket expenses for Medicare-approved surgeries. These plans coordinate with Medicare to fill the coverage gap and reduce the patient’s 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 typically cover any remaining coinsurance or small deductibles, which generally range between $100 and $300, depending on your plan and provider network.

Workers’ Compensation

If your trapezius muscle transfer is required due to a work-related injury or nerve damage, Workers’ Compensation will cover all related medical expenses, including surgery, postoperative care, and physical therapy. 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 or nerve injury requiring a trapezius transfer is caused by an automobile accident, No-Fault Insurance will typically cover the full cost of treatment, including surgery and rehabilitation. The only possible out-of-pocket cost may be a small deductible or co-payment depending on your policy.

Example

Robert Allen underwent a trapezius muscle transfer (CPT 23395) to restore shoulder motion following a brachial plexus injury. His estimated Medicare out-of-pocket cost was $304.12. Since Robert 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 a trapezius muscle transfer?
A. A trapezius muscle transfer is a surgical procedure used to restore shoulder function by repositioning the trapezius muscle to compensate for a paralyzed or non-functional deltoid or rotator cuff.

Q. When is a trapezius muscle transfer recommended?
A. It is recommended in cases of massive irreparable rotator cuff tears, brachial plexus injury, or deltoid paralysis when other treatments have failed to restore function.

Q. What is the goal of trapezius muscle transfer surgery?
A. The goal is to restore active elevation of the shoulder, improve function, and reduce disability in patients with compromised shoulder muscles.

Q. Which part of the trapezius muscle is used in this surgery?
A. The lower and middle fibers of the trapezius muscle are typically used for transfer.

Q. How is the trapezius muscle reattached during the procedure?
A. The muscle is detached from its original position and reattached to the humerus using tendon grafts or synthetic materials to replicate rotator cuff function.

Q. What type of anesthesia is used for this surgery?
A. The procedure is typically performed under general anesthesia.

Q. What is the recovery process like after trapezius muscle transfer?
A. Recovery involves immobilization of the shoulder followed by physical therapy to gradually restore motion and strength.

Q. How long does it take to recover from trapezius muscle transfer surgery?
A. Recovery can take several months, depending on the extent of the surgery and the individual patient’s healing process.

Q. What are the potential benefits of this surgery?
A. Potential benefits include improved shoulder elevation, decreased pain, and enhanced quality of life for patients with previously limited shoulder function.

Q. Are there any risks associated with trapezius muscle transfer?
A. Risks may include infection, nerve injury, failure of the transfer, or inadequate improvement in shoulder function.

Q. Who is a good candidate for this surgery?
A. Good candidates are patients with functional trapezius muscles but non-functional deltoid or rotator cuff muscles, and who have not benefited from other treatments.

Q. What type of physical therapy is needed after the procedure?
A. Physical therapy focuses on gentle range-of-motion exercises followed by strengthening as healing progresses, tailored to the patient’s specific needs.

Q. Can this procedure be done on patients with brachial plexus injuries?
A. Yes, it is often used in patients with brachial plexus injuries to improve shoulder mobility.

Q. Is the transferred trapezius muscle strong enough to lift the arm?
A. Yes, the muscle is capable of compensating for lost shoulder function when transferred and rehabilitated appropriately.

Q. What imaging is used to plan the surgery?
A. Imaging such as MRI or CT scans may be used to assess the condition of the shoulder muscles and joints before surgery.

Q. How successful is trapezius muscle transfer in restoring shoulder function?
A. It can be highly successful in improving active range of motion and reducing disability in properly selected patients.

Summary and Takeaway

Trapezius muscle transfer is a powerful reconstructive option for patients who have lost shoulder movement due to nerve injury or irreparable muscle damage. By rerouting a functioning muscle, it restores arm elevation and external rotation without the need for shoulder replacement. Ideal candidates are younger, active individuals with preserved joint motion but poor active control. When performed by experienced surgeons and followed by dedicated rehabilitation, this procedure offers substantial and lasting improvement in shoulder function.

Clinical Insight & Recent Findings

A recent study conducted at 15 Khordad Hospital in Tehran evaluated the therapeutic results of trapezius muscle transfer in 21 patients with brachial plexus injury, comparing outcomes between transfers from the same shoulder (ipsilateral) and the opposite shoulder (contralateral).

The study found that both techniques improved shoulder abduction and external rotation, with patients achieving over 90° of motion in up to half of cases, minimal postoperative pain, and high satisfaction rates. Notably, the contralateral transfer proved to be a reliable option when the affected side’s trapezius was unusable, showing good strength and no impairment of the healthy shoulder.

These findings support trapezius transfer as an effective reconstructive option to restore functional arm movement in cases of nerve injury or massive rotator cuff loss, complementing the described surgical techniques and recovery pathway for patients seeking to regain shoulder mobility. (“Study on trapezius muscle transfer – see PubMed.“)

Who Performs This Surgery? (Specialists and Team Involved)

Trapezius transfer is performed by orthopedic or reconstructive surgeons specializing in shoulder surgery and peripheral nerve reconstruction. The team includes anesthesiologists, surgical nurses, and physical therapists who oversee post-operative rehabilitation.

When to See a Specialist?

You should consult a shoulder or nerve specialist if you have persistent shoulder weakness or inability to lift or rotate your arm following trauma, nerve injury, or failed rotator cuff repair.

When to Go to the Emergency Room?

Seek immediate care if you experience severe shoulder pain, loss of sensation, or wound complications such as bleeding, swelling, or infection after surgery.

What Recovery Really Looks Like?

Recovery requires patience and active participation in physical therapy. The first few weeks focus on protection and gradual mobilization, followed by strengthening phases. By 6–12 months, most patients regain functional arm elevation and improved shoulder control.

What Happens If You Delay Surgery?

Delaying surgery may lead to muscle atrophy, joint stiffness, and irreversible weakness. Early evaluation ensures better outcomes and preserves remaining shoulder mobility.

How to Prevent Recurrence or Failure?

Adhering to rehabilitation, avoiding premature lifting, and maintaining scapular and shoulder conditioning are key to successful long-term outcomes.

Nutrition and Bone or Joint Health

A diet rich in lean protein, omega-3 fatty acids, and vitamins C and D supports healing and muscle regeneration. Avoid smoking, as it reduces tissue oxygenation and slows recovery.

Activity and Lifestyle Modifications

After recovery, most patients return to everyday tasks, light exercise, and even some sports activities. Avoid repetitive heavy lifting or high-impact movements to protect the reconstructed shoulder. With proper care and rehabilitation, trapezius transfer offers lasting improvement in shoulder strength, mobility, and independence.