A hernia forms when an internal organ or fatty tissue pushes through a weak spot in the surrounding muscle or connective tissue, most commonly in the abdominal wall. Surgical mesh acts as an internal scaffold, reinforcing this weakened area after the protruding tissue is returned to its proper place. Mesh placement is the standard of care in many repairs because it significantly reduces the rate of recurrence compared to using only sutures. Fixation is required to keep the mesh securely positioned, preventing movement or migration until the body’s natural healing process can integrate it permanently.
Immediate Mechanical Fixation Techniques
Surgeons use several methods for immediate mechanical fixation. The traditional approach involves securing the mesh with non-absorbable or absorbable sutures, which offer a strong initial hold and distribute tension well. However, suture placement can be time-consuming and carries a small risk of nerve entrapment, potentially causing postoperative pain.
Specialized fixation devices, often called tacks or staples, are deployed using handheld instruments. These devices are faster to apply than sutures, making them useful in minimally invasive procedures. Tacks can be permanent or absorbable, dissolving within 12 to 18 months.
A less traumatic, non-mechanical technique uses surgical glues or sealants, such as fibrin glue. Glues adhere the mesh with a broad contact area, potentially reducing chronic postoperative pain associated with pointed fixation devices. While quick and gentler, glues offer a less robust immediate hold, often reserving them for smaller hernias. Some modern meshes are also self-gripping, featuring micro-fasteners that grip the tissue without requiring additional tacks or sutures.
The Role of Biological Integration in Stability
While mechanical fixation provides initial security, long-term stability depends on the body’s biological response to the implanted material, known as tissue integration, where native tissue grows into and around the mesh structure. The body’s inflammatory response initiates fibroplasia, leading to the formation of scar tissue (fibrosis). This dense fibrotic tissue infiltrates the mesh pores, creating a strong, biological composite material that permanently reinforces the abdominal wall.
The quality of integration is heavily influenced by the mesh’s physical characteristics, especially its pore size. Large-pore or lightweight meshes are preferred because they allow for better tissue ingrowth and vascularization, resulting in more flexible and robust integration compared to dense, small-pore materials. For non-absorbable meshes, this integrated scar tissue provides permanent strength, making the initial mechanical fixation less significant over time. Even absorbable meshes act as temporary scaffolds, guiding the body to deposit new connective tissue that provides lasting reinforcement after the mesh dissolves.
How Surgical Approach Affects Mesh Placement
The surgical technique used dictates the preferred type of mesh fixation. Open hernia repair involves a larger incision, providing ample space and direct visibility. Sutures are common and reliable here, allowing for precise, manual placement with a strong anchor.
Conversely, minimally invasive procedures (laparoscopic or robotic-assisted) access the hernia through small incisions. The limited workspace makes manual suturing technically challenging and time-consuming. Consequently, surgeons rely on specialized fixation devices like tacks or staples, which are deployed rapidly and efficiently through the small ports.
The location of mesh placement also affects the fixation method in minimally invasive repairs. When the mesh is placed in the extraperitoneal space, tissue adhesives or a non-fixation approach may be considered for smaller hernias. This is preferred to reduce nerve irritation and chronic pain, which can be a side effect of mechanical fixation devices placed near sensitive structures.