Trapezius Muscle Transfer

When the shoulder loses its ability to lift or rotate the arm due to nerve damage or severe muscle tears, one innovative surgical solution is the trapezius muscle transfer. This procedure helps restore movement and strength by rerouting part of the trapezius muscle—normally responsible for moving the shoulder blade—so it can assist other muscles that have lost function.

Why Consider Trapezius Transfer?

The trapezius transfer is typically considered when:

• Nerve repair surgery hasn’t succeeded (especially in brachial plexus injuries)
• The rotator cuff tear is too severe to repair directly
• Patients want to regain shoulder function without undergoing shoulder fusion or joint replacement, especially in younger individuals

This technique helps patients regain abduction (lifting the arm to the side) and external rotation (turning the arm outward), which are vital for reaching and functional arm use.

Understanding the Shoulder Problem

In conditions like brachial plexus injuries or massive rotator cuff tears, patients may lose control of shoulder muscles such as the deltoid, supraspinatus, and infraspinatus. This leads to weakness, poor range of motion, and sometimes complete inability to move the shoulder outward or upward.

When these critical muscles can’t function, the trapezius—especially the lower portion—can be re-routed to help replace that lost movement.

How the Procedure Works

There are several surgical variations, but the goal is the same: reroute the lower (or sometimes upper) trapezius muscle and attach it to a different part of the shoulder where function is missing.

Common Surgical Techniques:

1. Direct Lower Trapezius Transfer
   The lower trapezius is detached from the spine of the scapula and redirected to attach near the infraspinatus or other rotator cuff tendons. When possible, this is done without a graft, particularly in patients with brachial plexus palsy and preserved shoulder anatomy.
2. Graft-Augmented Transfer
   When a direct connection is too short, surgeons use a tendon graft—commonly an Achilles tendon allograft or a semitendinosus autograft—to extend the muscle and secure it to the humeral head. This is especially common in massive rotator cuff tears where long distances must be bridged.
3. Modified Trapezius Transfer
   In the modified technique, the trapezius is harvested with part of its bone attachment and extended with a folded fascia lata graft. This combined unit is anchored close to the deltoid insertion, allowing the transferred muscle to mimic natural shoulder motion.

Surgical Steps in the Modified Approach

• A U-shaped incision is made over the scapula and clavicle, and an S-shaped incision is placed on the upper arm.
• The trapezius muscle is carefully separated, along with a portion of bone from its natural attachment.
• A strip of tensor fascia lata (from the thigh) is folded and stitched to extend the length of the muscle.
• The extended trapezius is sutured near the deltoid insertion with the arm held in about 110° of abduction.

Recovery After Surgery

Recovery is a critical part of the success of trapezius transfer surgery:

1. Immobilization: The arm is placed in a cast or brace in an abducted position (~130°) for the first four weeks.
2. Early Movement: Hand and elbow exercises begin immediately; isometric muscle activation of the transferred muscle starts within the first week.
3. Rehabilitation: Around week 5, the arm is progressively brought back to normal position, and shoulder-specific exercises are introduced.
4. Strengthening: Over time, patients undergo resistance training to build strength in the transferred muscle.

What Patients Can Expect

The results of trapezius transfer can be very encouraging:

• Patients often see major improvements in the ability to lift the arm (abduction) and rotate it outward.
• In one study, patients with brachial plexus injury improved shoulder abduction from 37° to 116°, with reduced disability scores as well.
• For rotator cuff tear patients, there was a reported average gain of 37.5° in forward elevation and 34.3° in external rotation, helping many return to daily activities.

Benefits of the Procedure

• Restores functional movement in patients who had lost the ability to lift or rotate the shoulder
• Avoids joint replacement, especially useful in younger, active patients
• Can be performed with or without arthroscopy, depending on the approach

Potential Challenges

• Requires careful surgical planning to avoid injury to the accessory nerve
• In cases where grafts are used, there is a small chance of graft failure or donor site complications
• Muscle strain and over-tensioning can impact results, so surgeon expertise is key

Is It Right for You?

If you’ve had a severe shoulder injury or nerve damage and are unable to move your arm outward or upward, trapezius transfer may be a valuable option. The best candidates are those with preserved passive motion but poor active control due to nerve damage or irreparable muscle tears.

Conclusion

Trapezius muscle transfer is a promising surgical option for restoring shoulder motion when traditional nerve or muscle repairs are not possible. With the right patient selection and careful surgical technique, it offers meaningful improvement in quality of life, helping patients regain arm function and independence.

If you’re experiencing shoulder dysfunction and wondering if this surgery might help, consult your orthopedic surgeon for a detailed evaluation tailored to your condition.

 

Do you have more questions?

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.