Midline Incision
When the linea alba is incised, this creates a midline incision—a vertical approach through the skin, subcutaneous tissue, linea alba, and peritoneum. 1
Definition and Classification
A midline incision is specifically defined as a vertical incision that passes through:
- Skin
- Subcutaneous tissue
- Linea alba (the key anatomical structure)
- Peritoneum 1
This distinguishes it from other abdominal incisions such as paramedian (which transects the rectus sheath and muscles near the linea alba), transverse (including the Pfannenstiel), or oblique approaches (such as Kocher or McBurney incisions). 1
Clinical Context and Indications
The midline laparotomy remains the incision of choice in emergency settings when hemodynamically unstable patients require rapid exploration, as it provides the fastest access to all organs of the peritoneal cavity. 1, 2
However, when clinical circumstances permit and preoperative imaging clearly identifies the pathology site, alternative incisions should be strongly considered due to superior outcomes. 1
Important Clinical Caveat
Midline incisions carry significantly higher rates of incisional hernia compared to transverse or oblique approaches. 1 The 2023 World Society of Emergency Surgery guidelines provide high-certainty evidence that non-midline incisions result in:
- Lower incisional hernia rates 1
- Less negative impact on pulmonary function 1
- Reduced wound dehiscence and burst abdomen 1
- Decreased postoperative pain 1
For laparoscopic specimen extraction, a midline extraction site should be avoided (strong recommendation, high-certainty evidence), with transverse incisions such as Pfannenstiel strongly preferred. 1, 2