VERSIONE ITALIANA

Frequency:

It ‘s a very common disease. It is estimated that in US every year 800,000 patients undergo inguinal hernioplasty. Inguinal hernia affects almost exclusively men, from birth to adulthood. Only 2% of women are affected by this pathology.

Etiology:

The genesis of inguinal hernia to date is still unknown. Only recently the presence of degenerative tissue damages in patients with inguinal hernia has been highlighted. These degenerative injuries are consistent with chronic compression damage, affecting all inguinal structures: muscles, arteries, veins, and nerves. (1, 2, 3, 4, 5) These scientific evidences lead to the statement that inguinal hernia is a degenerative disease of the structures of the inguinal region.

Treatment

The only way to treat inguinal hernia is surgery, which must be scheduled before the protrusion increases in volume. In fact, over time the size of the hernia increases and, consequently, also the risk of complications such as obstruction or strangulation arises. These are very risky complications, involving 10% of patients. In these cases incarceration of the visceral content within the hernia can occur (actually a loop of intestine) that, if not promptly returned back to the abdominal cavity, can provoke intestinal necrosis resulting in peritonitis. In such instances, an emergency procedure with high risks of complications is required.

Surgical techniques and materials

Over the years various hernia repair techniques have been developed. The oldest technique, practiced until the end of the last century, was performed by Edoardo Bassini, director of surgical clinic of the University of Padua. In 1884 he developed the Bassini repair technique for inguinal hernia by reconstruction of the inguinal myotendineal structures with stitches. Many variations of this procedure have been developed through the years, among these the  Shouldice and Mc Vay technique. In 1960, with Usher, first one to use a piece of synthetic tissue to cover the hernia orifice, the era of hernia repair with biocompatible implants begins. Lichtenstein improved the prosthetic hernia repair procedure by standardizing the technique and fixing the mesh with sutures. Another innovative contribution has been achieved with Trabucco, who in addition to covering the hernia orifice with a pre-shaped implant without sutures, delivered a synthetic plug into it. However, all these techniques have been developed without adequate understanding of the causes of the genesis of hernia, which as mentioned, is still unknown. Therefore these methods do not take into account the physiology of the inguinal region and, requiring implant fixation with sutures or similar, do not respect the dynamics of the abdominal wall. Prostheses used today are mostly made of polypropylene. They are usually flat, aiming to reinforce the inguinal region by mean of an inflammatory response leading to the ingrowth of a fibrotic scar plate. After the first 6 months of implantation the prosthesis tends to shrink losing up to 30% of the surface. Shrinkage can be as high as 70% in the case of the plug.

All conventional implants used until now are static, being placed by the surgeon in one of the most mobile area of the body. These prostheses are often connected in various ways to the inguinal structures. Since they are fixed do not cope the movement of the inguinal muscles, impairing the dynamics of the groin. The poor quality of tissue ingrowth, a stiff and shrunken scar plate, can cause patient’s discomfort and, in some cases, even chronic pain. The latest scientific studies demonstrate that after 7 years inguinal hernia repair with conventional meshes, 7% of patients are still affected by chronic pain. (6) Although at first glance this might seem a low percentage, it means that among the 800,000 inguinal hernia repairs performed each year in USA, over 56,000 patients will suffer chronic pain. This means permanent pains.

In addition, other complications are related to the non-physiological surgical maneuvers, such as mesh fixation, which hinders the mobility of the muscles and tears the tissue. These are bleeding, hematoma, infection, mesh dislocation, traumatic injuries of the spermatic cord structures and recurrence. Also, poor quality of tissue ingrowth within the static meshes causes the so-called discomfort, which could have impact on quality of life for which can be severe.

Today, as an alternative to conventional systems, a new prosthetic device is available for a more physiologic inguinal hernia repair. This implant is 100% fixation free, promotes the regeneration of the normal tissues, same as natural abdominal wall structures, thus restoring a condition close to normal.

The dynamic implant: the new frontier in inguinal hernia repair

Protesi dinamica inguinale

Groin hernia is among the most frequent surgical procedures. Despite all the efforts made in researching the true reasons of its origin, even today the genesis of inguinal hernia is not well understood. Conversely, many efforts and many resources have been spent in developing new materials and devices for hernia repair. At this point an essential question should be made: how can we manage a disease without understanding the real basis of its origin? Moreover: can the reason for current (still high) rate of complications and recurrences lie in this unanswered question?

In recent years Prof. Giuseppe Amato has performed several investigations on the genesis of the hernia disease. These studies were carried out in collaboration with the Department of Pathological Anatomy of the, University of Trieste, directed by Prof. Furio Silvestri. (1, 2, 3, 4, 5) Years of research performed in tissue specimens taken from both cadavers and living patients with inguinal hernia, demonstrated that in those patients a broad range of tissue degeneration is found the groin structures. These degenerative injuries concur to the weakening of the inguinal tissue, until a hernia protrusion arises.

Then, being the tissue degeneration the cause of the weakening of the inguinal structures, Prof. Amato focused his research on one aspect: how can we achieve regeneration of the tissue of the inguinal area to consequently manage the hernia disease? And also: is it possible to avoid fixation in inguinal hernia repair?

Working on these concepts, as a solution of the problem, Professor Amato has developed a dynamic – self retaining implant which promotes an enhanced biological response leading to tissue regeneration. This newly designed implant is dynamic, compliant with the structures of the groin. Its movements, in harmony with the inguinal structures, stimulate tissue regeneration. The implant is delivered into the hernia opening, in a compressed mode, by mean of a proprietary device. Once delivered it expands and obliterates the defect (fills the gap). The implant is self-retaining, therefore nor suture stitches neither other fixations are needed. The implant stays firm within the inguinal wall even during cough test in patients who underwent hernia repair with local anesthesia. The experimental study that proves this data has already been published in the scientific journal “Artificial Organs”. (7)

The surgical technique of dynamic hernia repair: how it works

Preparation and positioning of the patient for the procedure follows normal routine, as per surgeon’s preference.The dynamic implant is delivered into the hernia orifice through a proprietary delivery device. At this stage, the prosthesis is compressed into the housing of the introducer.  By pushing the plunger of the introducer, the prosthesis is released into hernia orifice and expands inside it. The introducer is then removed, leaving the prosthesis inserted into the hernia gap. No sutures or fixations are needed. After checking the correct positioning, the surgeon closes the wound, possibly with a fully intradermal technique. (8)

Advantages for the patient

The advantages for the patient are:

  • Very high postoperative comfort.
  • Lower postoperative pain compared to conventional techniques
  • The dynamic implant does not cause the formation of fibrotic tissue, such as conventional prostheses.
  • Promotes the regeneration of healthy tissue inside its structure.  (9)
  • 100% Fixation free
  • Low rate of postoperative complications. Since it’s not fixated, typical complications of the conventional prostheses such as bleeding, hematoma, shrinkage, dislocation, migration, chronic pain can be avoided. (10)

Benefits for the surgeon

The advantages for the surgeon are:

  • Drastic reduction of operative time. The easy and fast positioning of the implant that does not require time for fixation.
  • Easy follow up control of implant placement, with a simple ultrasound examination (same as with pregnant women).
  • To date (over 100 series of cases) no chronic pain or recurrence
  • The learning curve for the technique is very short, estimated in about 5 procedures.

References

1)     Histological findings of the internal inguinal ring in patients having indirect inguinal hernia. Hernia 2009;13;259-62

2)     Reply to the letter: ”Histology of the internal inguinal ring: it is really a novelty?”. Hernia 2010;14:665-7

3)     Nerve degeneration in inguinal hernia specimens. Hernia 2011;15:53-58

4)     Damage to the vascular structures in inguinal hernia specimens. Published online “Hernia” Journal DOI 10.1007/s10029-011-0847-4

5)    Muscle degeneration in inguinal hernia specimens . Published online in “Hernia” Journal DOI 10.1007/s10029-011-0890-1

6)    Long-term outcome after randomising Prolene Hernia System, Mesh Plug Repair and Lichtenstein for inguinal hernia repair Hernia (2011) 15 (Suppl 2): S1-S35

7)    A new prosthetic implant for inguinal hernia repair: its features in a porcine experimental model. Artificial Organs 2011;35(8):E181–E190

8)   Suture intradermiche totali. G Chir. 2010;1/2:48-54

9 )   Dynamic implant for inguinal hernia repair in porcine experimental model. A feasibility study. Hernia 2009;13:S1-332

10)   Dynamic autostatic implant for inguinal hernia repair. Early results in an explorative cohort of patients. Hernia 2010;14:S55-S100