Hand Tendon Transfer

Tendon transfers are crucial surgical procedures that help restore lost or compromised function in cases of nerve injuries, congenital abnormalities, or musculoskeletal conditions. These surgeries are often employed when nerve recovery is unlikely or insufficient, providing a substitute by rerouting tendons from one functional unit to another. This approach is essential in cases where muscle action is disrupted, and restoring function becomes a necessity for the patient’s quality of life.

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

Tendon transfers are commonly performed in patients with conditions such as stroke, cerebral palsy, polio, or peripheral nerve injuries. These conditions often lead to muscle weakness or loss of function in the hand, forearm, or upper extremities. Tendon transfer surgeries are particularly common in patients who have suffered nerve injuries like radial nerve palsy or brachial plexus injuries, as well as congenital defects that impair muscle function.

Why It Happens – Causes (Etiology and Pathophysiology)

Tendon transfers are performed to compensate for lost muscle function caused by nerve damage, congenital abnormalities, or musculoskeletal conditions. When nerve damage is severe, such as in cases of trauma or stroke, the affected muscles lose their ability to perform normal functions. Tendon transfer surgery reroutes functional tendons to restore movement, particularly when nerve regeneration or healing is not expected. By utilizing muscles that are still intact, tendon transfers can help patients regain some of their lost abilities.

How the Body Part Normally Works? (Relevant Anatomy)

Tendons are the connective tissues that attach muscles to bones. In the hand and upper extremities, tendons allow for a wide range of motion, from gripping to precise finger movements. The muscles in the forearm and hand are controlled by peripheral nerves, such as the radial, ulnar, and median nerves. When these nerves are damaged, their associated muscles lose function. Tendon transfers help to bypass the damaged nerve and use alternative muscles to perform the lost movements.

What You Might Feel – Symptoms (Clinical Presentation)

Patients requiring tendon transfer surgery often experience symptoms related to muscle weakness or loss of function, such as:

• Inability to perform fine motor tasks (e.g., buttoning a shirt or holding a pencil).

• Weakness in the hand, wrist, or fingers.

• Loss of coordination or control of hand movements.

• In cases of nerve injury, additional symptoms like numbness, tingling, or muscle atrophy may be present.

How Doctors Find the Problem? (Diagnosis and Imaging)

Diagnosis of the need for tendon transfer involves a thorough clinical examination to assess muscle strength, function, and the extent of nerve damage. Electromyography (EMG) is commonly used to evaluate the function of the muscles and nerves, providing insights into the degree of nerve injury. Imaging studies like MRI or ultrasound may also be used to assess soft tissue conditions or to identify any mechanical constraints that could affect tendon movement.

Classification

Tendon transfers can be classified based on the type of muscle and tendon involved. There are different approaches depending on the extent of nerve damage and the muscle group that needs to be restored:

• Radial Nerve Palsy: Often treated with transfers involving wrist and finger extensors.

• Brachial Plexus Injury: Tendon transfers may involve multiple muscle groups in the shoulder, arm, or hand.

• Congenital Abnormalities: Tendon transfers may be used to improve function in cases where muscle development has been impaired.

Key Principles of Tendon Transfer

1. Preoperative Assessment

Before proceeding with tendon transfer surgery, it is essential to evaluate the patient’s overall condition. This includes assessing the cause and extent of muscle function loss, available donor muscles for transfer, and the patient’s overall health. The surgeon must also ascertain the patient’s expectations and establish realistic goals for recovery. This is particularly crucial as tendon transfer surgery, although effective, may not always fully restore all lost functions.

Electrodiagnostic tests, including electromyography (EMG) can be extremely helpful in gauging the extent of nerve damage and predicting potential recovery. These studies can also assist in identifying expendable muscles for transfer, such as the pronator teres in cases of radial nerve palsy.

2. Timing and Tissue Equilibrium

The concept of tissue equilibrium refers to ensuring that the surgical site is in optimal condition for the tendon transfer procedure. Scar tissue, edema, and joint stiffness can hinder the success of tendon transfers. Adequate healing and maturation of tissue must be achieved before the procedure is performed to ensure the best possible outcome. In certain cases, surgeons may resort to soft tissue flaps or silicone rods to create an ideal pathway for tendon rerouting.

3. Selection of Donor Muscles

One of the most critical aspects of tendon transfer surgery is choosing the right donor muscle. The donor muscle must possess sufficient strength and excursion to perform the desired function in the recipient area. Typically, the strength of a donor muscle is assessed using the Lovett scale, which ranks muscle strength on a scale from 0 (no movement) to 5 (full strength). An ideal donor muscle should have a grade of at least 4 or 5 to ensure the success of the tendon transfer.

Additionally, the donor muscle must be expendable, meaning its loss will not significantly compromise the function of the area it originally served. For example, the flexor carpi ulnaris may be used as a donor muscle in cases of radial nerve palsy, provided there is sufficient function remaining in the wrist flexors.

4. Excursion and Line of Pull

Excursion, or the distance a tendon can move, is vital for the success of the transfer. For a tendon transfer to be effective, the excursion of the donor tendon must closely match that of the recipient tendon. Factors such as muscle length, tendon fiber length, and joint range of motion play a role in determining the potential for successful tendon excursion. The surgeon aims to achieve the correct amount of tension in the donor tendon to facilitate smooth, functional movement in the recipient site.

The line of pull is another critical factor. The donor tendon should be re-routed with as straight a line as possible to avoid complications such as excessive tension or misalignment. The transfer’s efficiency is compromised if the tendon must pass through multiple redirecting pulleys or undergo excessive tensioning.

5. Synergism

Synergism in tendon transfers refers to the idea that the donor muscle should contract in sync with the recipient muscle to enhance the effectiveness of the transfer. For example, transferring a wrist flexor to a finger extensor in cases of radial nerve palsy is a synergistic transfer that ensures coordinated movement. These types of transfers are easier to learn and are particularly beneficial for younger patients with higher levels of neural plasticity.

Other Problems That Can Feel Similar (Differential Diagnosis)

Other conditions, such as joint stiffness, arthritis, or other musculoskeletal disorders, can mimic the symptoms of muscle weakness or loss of function. A comprehensive evaluation, including electrodiagnostic testing and imaging, helps distinguish between tendon dysfunction and other conditions that may affect hand or upper extremity function.

Treatment Options

Non-Surgical Care

In many cases, conservative treatments such as physical therapy, splints, and strengthening exercises may help improve muscle function and reduce symptoms. However, when nerve regeneration is unlikely or the condition is severe, tendon transfer surgery becomes the best option for restoring lost function.

Surgical Care

Tendon transfer surgery involves rerouting tendons from one functional area to another to restore movement and strength. The procedure may involve:

• End-to-end or end-to-side tendon coaptation: For directly joining tendons.

• Pulvertaft weave: A technique used to securely attach the donor tendon to the recipient tendon using cross-stitches.

• Loop-tendon suture: Allows for adjustments during healing, often preferred for its simplicity and strength.

Recovery and What to Expect After Treatment

Recovery from tendon transfer surgery involves a period of immobilization followed by physical therapy to restore muscle strength and functionality. Rehabilitation is critical for retraining the brain to adapt to the new tendon function. Patients may need several months to fully regain function, with the timing depending on the complexity of the surgery and the type of tendon transfer performed.

Possible Risks or Side Effects (Complications)

As with any surgery, tendon transfer carries potential risks, including:

• Infection at the surgical site.

• Scar tissue formation or contracture, which may hinder tendon movement.

• Nerve damage or recurrence of original symptoms.

• Overuse injuries due to the transferred tendon being subjected to different stress loads.

Long-Term Outlook (Prognosis)

The success of tendon transfer surgeries is generally high, with many patients experiencing significant improvements in hand and upper extremity function. However, the extent of recovery depends on factors like the severity of nerve damage, the type of tendon transfer performed, and the patient’s overall health and adherence to rehabilitation protocols. Most patients regain sufficient function to perform daily tasks, but complete recovery of all lost functions is not always possible.

Out-of-Pocket Cost

Medicare

CPT Code 26480 – Hand Tendon Transfer: $170.47

Under Medicare, 80% of the approved amount for this procedure is covered once the annual deductible has been met. The remaining 20% is typically the patient’s responsibility. Supplemental insurance plans—such as Medigap, AARP, or Blue Cross Blue Shield—usually cover this 20%, leaving most patients with little to no out-of-pocket expenses for Medicare-approved hand tendon transfer surgeries. These supplemental plans coordinate directly with Medicare to provide full coverage for the procedure.

If you have secondary insurance—such as Employer-Based coverage, TRICARE, or Veterans Health Administration (VHA)—it serves as a secondary payer once Medicare processes the claim. After your deductible is satisfied, these secondary plans may cover any remaining balance, including coinsurance or small residual charges. Secondary plans typically have a modest deductible, usually between $100 and $300, depending on the specific policy and network status.

Workers’ Compensation
If your hand tendon transfer surgery is work-related, Workers’ Compensation will fully cover all treatment-related costs, including surgery and rehabilitation. You will have no out-of-pocket expenses under an accepted Workers’ Compensation claim.

No-Fault Insurance
If your hand tendon transfer surgery is the result of a motor vehicle accident, No-Fault Insurance will cover the full cost of the procedure. The only possible out-of-pocket cost may be a small deductible depending on your individual policy terms.

Example
Tom, a 62-year-old patient with a hand injury requiring tendon transfer (CPT 26480), had an estimated Medicare out-of-pocket cost of $170.47 for the surgery. Since Tom had supplemental insurance through AARP Medigap, the 20% that Medicare did not cover was fully paid, leaving him with no out-of-pocket expenses for the procedure.

Frequently Asked Questions (FAQ)

Q. How long does it take to recover from tendon transfer surgery?
A. Recovery time varies, but most patients can expect a full recovery within 3 to 6 months, depending on the complexity of the surgery and the rehabilitation process.

Q. Will I be able to fully restore my hand function after tendon transfer surgery?
A. While tendon transfer surgery can significantly improve function, complete restoration of all hand movements may not always be possible. However, many patients experience significant functional improvements that allow them to resume daily activities.

Q. Are there any risks of complications after tendon transfer surgery?
A. As with any surgical procedure, tendon transfer surgery carries risks, including infection, scarring, nerve damage, or recurrent weakness. Close monitoring during recovery helps mitigate these risks.

Clinical Insight & Recent Findings

A recent study explored the use of early tendon transfer in diabetic hand infections, particularly in a case complicated by compartment syndrome. The patient, who experienced necrosis of the flexor pollicis longus, underwent tendon transfer using the palmaris longus to restore thumb flexion.

This early intervention, performed after infection resolution, significantly enhanced functional recovery and prevented long-term disability. The use of palmaris longus for tendon transfer is highlighted as an effective, minimally invasive approach, particularly in cases with good local tissue conditions, as it offers both functional recovery and low donor site morbidity.

The case underlines the importance of early reconstruction in diabetic hand infections to optimize patient outcomes and preserve hand function. (“Study of tendon transfer in diabetic hand infections – See PubMed.”)

Who Performs This Treatment? (Specialists and Team Involved)

Tendon transfer surgeries are typically performed by orthopedic surgeons or hand surgeons with expertise in nerve injuries and musculoskeletal disorders. A multidisciplinary team, including physical therapists and rehabilitation specialists, is often involved in post-operative care to ensure optimal recovery.

When to See a Specialist?

You should consult a specialist if you have sustained a peripheral nerve injury or have a congenital condition affecting hand or arm function. If conservative treatments fail to improve muscle strength or function, tendon transfer surgery may be considered.

When to Go to the Emergency Room?

Emergency care may be necessary if there is acute nerve injury resulting in sudden loss of hand or arm function, or if you experience severe pain, swelling, or signs of infection following surgery.

What Recovery Really Looks Like?

Recovery from tendon transfer surgery involves several months of rehabilitation to strengthen the transferred tendon and retrain the brain to use it effectively. Patients may initially experience discomfort and limited function, but with time, they typically regain significant strength and movement.

What Happens If You Ignore It?

Ignoring a nerve injury or muscle imbalance can lead to permanent loss of function in the affected area. Tendon transfer surgery offers a potential solution to restore function and improve quality of life when other treatments fail.

How to Prevent It?

Preventing nerve injuries and muscle imbalances involves proper ergonomics, avoiding repetitive stress, and managing conditions that may contribute to nerve damage. In patients with congenital abnormalities, early intervention and surgical management can help prevent more severe impairments later in life.

Nutrition and Bone or Joint Health

Maintaining a healthy diet rich in calcium, vitamin D, and other essential nutrients supports bone and joint health. Proper nutrition can also help reduce inflammation and improve healing after surgery.

Activity and Lifestyle Modifications

After tendon transfer surgery, patients should gradually return to normal activities, avoiding excessive use of the transferred tendon. Modifications to daily routines may be necessary to prevent overloading the newly transferred tendon, ensuring its successful integration into the functional unit.