What are the different types of sternal incisions?

October 1, 2025 •

4 min read

Over 800,000 heart surgeries are performed annually in the U.S., many of which require a sternal incision to access the heart and surrounding structures. Understanding what are the different types of sternal incisions can provide clarity for patients preparing for surgery and help demystify the process.

Quick Summary

The main types of sternal incisions include the full-length median sternotomy for major open-heart procedures, smaller mini-sternotomies for less invasive surgeries, and transverse clamshell or hemi-clamshell incisions for specific complex cases.

Key Points

Median Sternotomy: The most common, full vertical incision for open-heart surgeries like CABG and valve replacements.
Mini-Sternotomy: A smaller, minimally invasive vertical incision used for less complex cardiac procedures, leading to faster recovery.
Hemisternotomy: A partial sternal split, either upper or lower, allowing targeted access for specific valve or grafting procedures.
Clamshell Incision: A transverse, bilateral incision for extensive access needed in complex cases like double lung transplants or major trauma.
Redo Sternotomy: The re-opening of a previous sternal incision for repeat surgeries, which carries an increased risk of complications.
Incision Choice Factors: The type of incision depends on the procedure's complexity, the required access, and the surgeon's assessment.

The Core of Sternal Incisions: Median Sternotomy

The median sternotomy is arguably the most common and classic approach used in cardiothoracic surgery. This involves a vertical incision made from the top of the sternal notch down to the xiphoid process, providing a wide-open view of the thoracic cavity.

Indications for Median Sternotomy

Coronary Artery Bypass Grafting (CABG): This is one of the most frequent uses for a median sternotomy, allowing surgeons full access to the heart to bypass blocked arteries.
Heart Valve Replacements: Whether replacing an aortic, mitral, or tricuspid valve, this incision provides the necessary exposure.
Heart Transplants: The comprehensive access is essential for a complete heart transplant procedure.
Congenital Heart Defect Repair: For more complex repairs in children or adults, a median sternotomy offers the best visibility.

The Median Sternotomy Procedure

Skin Incision: A vertical incision is made through the skin and subcutaneous tissue.
Sternal Division: A specialized saw is used to carefully split the sternum down the middle.
Retraction: A sternal retractor is used to spread the two halves of the breastbone, revealing the heart and lungs.
Closure: After the procedure, the sternum is re-joined, most commonly with stainless steel wires, and the skin is closed.

Minimally Invasive Sternal Incisions

Advancements in surgical techniques have led to less invasive options for certain procedures, resulting in smaller incisions, reduced trauma, and quicker recovery times.

Mini-Sternotomy

As the name suggests, a mini-sternotomy is a smaller version of the traditional median sternotomy. The incision is typically only a few inches long and is made in the upper or lower part of the sternum. This approach is ideal for single-valve surgeries.

Hemisternotomy

A hemisternotomy involves splitting only a portion of the sternum, either upper or lower, rather than the full length.

Upper Hemisternotomy: Used for minimally invasive procedures such as aortic valve replacement and some heart valve repairs.
Lower Hemisternotomy: Provides access for specific types of coronary artery bypass grafting, especially involving the right internal mammary artery.

Transverse and Other Specialized Incisions

For certain complex procedures, a horizontal incision or a re-opening of a previous incision may be necessary.

Clamshell Incision

Also known as a bilateral thoracosternotomy, this involves a horizontal incision across the chest, sometimes curved, with the sternum divided transversally. It is used for major trauma or bilateral lung transplants where maximum access is required.

Hemiclamshell Incision

This is a unilateral variation of the clamshell incision, providing extensive access to one side of the chest for a variety of thoracic procedures.

Redo Sternotomy

When a patient needs a second or subsequent open-heart surgery, a redo sternotomy involves re-opening the existing sternal incision. This procedure carries higher risks due to adhesions from the previous surgery, requiring careful planning and execution.

Emergency Re-sternotomy

This is an urgent procedure to reopen the sternal wound, typically in the ICU or operating room, to address complications like excessive bleeding or cardiac tamponade following an initial surgery.

Comparison of Sternal Incision Types


Feature	Median Sternotomy	Mini-Sternotomy	Clamshell Incision
Incision Type	Full vertical	Smaller vertical	Full transverse
Invasiveness	Most invasive	Minimally invasive	Highly invasive
Access	Excellent, wide	Limited, specific	Extensive, bilateral
Primary Uses	CABG, transplants	Single valve repair	Bilateral lung transplant, major trauma
Recovery	Longer, more pain	Shorter, less pain	Long, complex

Patient Considerations and Recovery

Regardless of what are the different types of sternal incisions, patient recovery involves several key phases. The surgical incision requires time to heal, which is followed by bone and tissue recovery.

Healing and Pain Management

Post-Operative Pain: All sternal incisions cause some level of pain, managed with medication. Minimally invasive approaches generally result in less severe and shorter-duration pain.
Sternal Precautions: Patients must often follow sternal precautions, limiting arm and upper body movement to protect the healing sternum.
Infection Risk: Superficial or deep sternal wound infections (DSWI) are a risk, especially with deeper incisions. Careful wound care and prophylactic antibiotics help minimize this risk.

The Scar and Long-Term Outcomes

Scar Appearance: The resulting scar's appearance varies by incision type and individual healing factors. A median sternotomy leaves a central chest scar, while mini and clamshell incisions result in different placements.
Sternal Instability: In some cases, the sternum may become unstable post-operatively, manifesting as pain or a 'clicking' sensation, which may require further intervention.

The Evolution of Surgical Approaches

The move towards less invasive surgical methods is a significant trend in cardiothoracic surgery. Innovations in technology, instruments, and visualization techniques allow surgeons to perform complex procedures through smaller incisions. While conventional sternotomy remains the gold standard for many complicated cases, minimally invasive procedures offer appealing benefits like reduced bleeding, shorter hospital stays, and potentially better cosmetic outcomes for select patients.

For further reading on the anatomy and clinical use of various cardiothoracic incisions, a comprehensive resource is provided by TeachMeSurgery.com.

Conclusion

The choice of sternal incision is a critical decision based on the specific surgical needs, the patient's condition, and the surgeon's expertise. From the extensive access of a median sternotomy to the targeted approach of a mini-sternotomy, each technique serves a distinct purpose. Knowing what are the different types of sternal incisions helps patients understand the procedure better and set appropriate expectations for recovery and long-term care.

Frequently Asked Questions

The most common type of sternal incision is the median sternotomy, a full-length vertical cut made down the center of the breastbone. It is widely used for major open-heart surgeries.

Yes, a mini-sternotomy is generally associated with less post-operative pain and a faster recovery time compared to a full median sternotomy due to the smaller incision size.

A clamshell incision, or bilateral thoracosternotomy, is used to provide extensive, bilateral access to the chest cavity. It is often employed for bilateral lung transplants or to treat major chest trauma.

A redo sternotomy involves re-opening a previous incision. It is considered more complex than the initial operation because the surgeon must work around existing scar tissue and adhesions, which increases the risk of complications.

Yes, different sternal incisions significantly affect recovery time. Less invasive procedures, like mini-sternotomies, typically have shorter hospital stays and quicker recovery than a full median sternotomy or a complex clamshell incision.

Risks can vary, but deeper, more extensive incisions carry a higher risk of complications like deep sternal wound infection (DSWI). Redo sternotomies have specific risks related to potential damage to underlying structures due to scar tissue.

The surgeon's decision is based on several factors, including the type and complexity of the procedure, the amount of access required, the patient's anatomy, and the potential benefits and risks of each approach.

The primary benefit is reduced surgical trauma, which leads to less post-operative pain, shorter hospital stays, and quicker overall recovery for the patient.