The Primary Landmarks of the Maylard Incision
The Maylard incision, also known as the Mackenrodt incision, is a specialized surgical approach that enables surgeons to achieve a wider and deeper field of view into the pelvic region. This is especially useful in complex gynecological procedures. The key landmarks define the incision's location and the critical anatomical structures that must be addressed during the procedure.
The Skin Incision
The initial external landmark is the transverse skin incision. Unlike the more common Pfannenstiel incision, which is positioned low along the pubic hairline, the Maylard incision is made 5 to 8 cm superior to the pubic symphysis. This higher placement allows for improved access to the deeper pelvic structures. The incision runs from one side of the abdomen to the other, creating a horizontal line parallel to the bikini line but positioned further up on the abdomen.
The Transverse Fascial and Muscle Cut
Beneath the skin, the rectus fascia and rectus abdominis muscles are key surgical landmarks. In a Maylard incision, the anterior rectus fascia is cut transversely. The procedure is distinguished by the fact that the bellies of the rectus muscles themselves are also cut horizontally. This direct transverse transection of the muscles, performed with an electrocautery device, is what provides the significantly wider exposure compared to muscle-splitting techniques.
The Inferior Epigastric Vessels
Perhaps the most crucial anatomical landmarks in the Maylard procedure are the inferior epigastric vessels. As the rectus muscles are transected, these vessels, which run along the posterior lateral border of the rectus muscle belly, are identified. They are then isolated, ligated (tied off), and divided. This step is vital for controlling bleeding and is a key difference between the Maylard and other transverse incisions like the Cherney, where the vessels may not need to be divided. However, care must be taken with patients who have peripheral arterial disease, as ligating these vessels could potentially affect collateral circulation to the lower extremities.
The Maylard Incision Procedure: A Step-by-Step Overview
The process of creating a Maylard incision follows a sequence of carefully planned steps to ensure optimal exposure and patient safety.
- Patient positioning and marking: The patient is placed in a dorsal supine position. The surgeon marks the intended incision line, typically 5-8 cm above the pubic symphysis.
- Skin and subcutaneous tissue incision: The skin and underlying subcutaneous fat are incised along the marked line, revealing the underlying rectus fascia.
- Fascial incision: The rectus fascia is incised transversely. Unlike the Pfannenstiel, the fascia is not separated from the underlying rectus muscles at this stage.
- Muscle transection and vessel ligation: The rectus muscles are cut transversely with electrocautery, carefully identifying and ligating the inferior epigastric vessels near the lateral edge of the muscle. This step is performed on both sides to complete the muscle transection.
- Peritoneal entry: The peritoneum is opened transversely, either in the midline or laterally, to gain access to the abdominal cavity.
- Closure: After the surgical procedure, the peritoneum is closed, and the cut rectus muscles are re-approximated by suturing the fascia. The muscle stumps themselves do not require direct suturing. The subcutaneous tissue and skin are then closed.
Maylard vs. Pfannenstiel Incisions: A Comparison
| Feature | Maylard Incision | Pfannenstiel Incision |
|---|---|---|
| Surgical Access | Extensive and wide access to the entire pelvic sidewall. | Limited access to the lateral pelvis. |
| Skin Incision Location | Transverse, 5-8 cm above the pubic symphysis. | Curved, 2 cm above the pubic symphysis along the bikini line. |
| Muscle Treatment | Rectus abdominis muscles are transected (cut) transversely. | Rectus abdominis muscles are split vertically and retracted. |
| Vessel Ligation | Inferior epigastric vessels are routinely ligated and divided. | Vessels are usually preserved, as they are not crossed. |
| Postoperative Pain | Higher pain level in the initial postoperative period, but studies suggest less need for analgesics long-term. | Often less initial postoperative pain. |
| Hernia Rate | Reduced rate of incisional hernia. | Potentially higher risk of incisional hernia compared to Maylard. |
| Cosmesis | Generally considered cosmetically appealing due to low transverse scar. | Very good cosmetic outcome, as the incision is low and curved. |
When is the Maylard Incision Used?
The Maylard incision is typically reserved for surgical procedures where broader and deeper pelvic exposure is necessary to safely and effectively address complex pathology. It offers superior access to the pelvic sidewalls compared to the Pfannenstiel incision. It is commonly used for:
- Radical hysterectomies for conditions such as advanced cervical cancer.
- Cytoreductive surgery for ovarian cancer.
- Management of large pelvic masses or endometriosis.
- Procedures requiring access to the pelvic sidewalls, such as internal iliac artery ligation.
- Some complex cesarean sections, particularly with multiple fetuses or large babies, to maximize exposure and minimize trauma during delivery.
The Advantages and Disadvantages
Advantages
- Extensive Exposure: Offers a superior view of the pelvis and its lateral sidewalls compared to other transverse incisions.
- Reduced Hernia Rate: The transverse muscle cut and fascial closure result in a strong abdominal wall repair, leading to a lower rate of incisional hernia.
- Cosmetic Appeal: The low transverse scar is more aesthetically pleasing than a vertical midline incision.
Disadvantages
- Increased Initial Pain: The muscle-cutting nature of the procedure can result in more severe pain during the initial postoperative week.
- Higher Blood Loss Risk: The ligation of the inferior epigastric vessels carries a risk of significant bleeding and hematoma formation. This risk is heightened if the vessels are not properly ligated.
- Potential for Collateral Circulation Issues: In rare cases of patients with peripheral arterial disease, ligation of the inferior epigastric vessels can compromise lower extremity blood flow.
- Experience-Dependent Technique: The procedure requires a higher level of surgical skill and familiarity, especially concerning the inferior epigastric vessels.
Conclusion
The Maylard incision landmark is defined by a transverse cut several centimeters above the pubic bone, a transection of the rectus abdominis muscles, and the crucial ligation of the inferior epigastric vessels. This muscle-cutting approach provides superior surgical exposure to the pelvic sidewalls for complex gynecological procedures. While it offers significant benefits, including a lower incisional hernia rate and good cosmetic results, it is a more invasive technique than a Pfannenstiel incision and carries a higher risk of immediate postoperative pain and bleeding. A surgeon will choose the Maylard incision based on the patient's specific anatomy and the extent of surgical access required.
For more detailed technical information, consult resources like the Atlas of Pelvic Surgery, which provides an extensive overview of this and other abdominal incisions.
