The narrow mesh: A new shaped mesh for the treatment of inguinal hernia

Inguinal hernia repair remains one of the most frequent procedures in general surgery , with some 20 million operations being performed worldwide each year. The prosthetic repair is now accepted worldwide as the gold standard in inguinal hernia repair [1]. Several studies claim its superiority over suture repair especially in cases of recurrent hernias. The mesh repair essentially bridges to cover the gap forming the hernia defect, without stretching patient's tissues over the defect, thus allowing tissues to remain 'tension-free'. On one hand the use of mesh in the inguinal hernia repair substantially reduced the recurrence rate and the rehabilitation period as compared to sutured repairs. On the other hand, the mesh brought with itself several complications, such as protrusion, extrusion, infection, intestinal fi stulization, and especially chronic inguinodynia [2,3].


Introduction
Inguinal hernia repair remains one of the most frequent procedures in general surgery , with some 20 million operations being performed worldwide each year. The prosthetic repair is now accepted worldwide as the gold standard in inguinal hernia repair [1]. Several studies claim its superiority over suture repair especially in cases of recurrent hernias. The mesh repair essentially bridges to cover the gap forming the hernia defect, without stretching patient's tissues over the defect, thus allowing tissues to remain 'tension-free'. On one hand the use of mesh in the inguinal hernia repair substantially reduced the recurrence rate and the rehabilitation period as compared to sutured repairs. On the other hand, the mesh brought with itself several complications, such as protrusion, extrusion, infection, intestinal fi stulization, and especially chronic inguinodynia [2,3].
Furthermore the mesh, once in place, is rigid, passive, adynamic, and aphysiological, addressing only the anatomical aspect of the posterior wall of the inguinal canal without restoring its function.
In the attempt of restoring not only the strength of the posterior wall of the inguinal canal but also its physiological properties of active contraction and passive relaxation, we propose a new alloplastic mesh, called narrow mesh (NM), 6 x 2.5 cm. in size, that is interposed between the conjoined tendon and the inguinal ligament and shaped in such a way to accommodate the spermatic cord without encircling it and ( Figure 1).

Abstract
The present communication relates to inguinal hernia repair, and more particularly to a preshaped inguinal hernia prosthetic material, polypropylene, 6×2.5 centimeters in size, (Figure 1) that has a lateral semicircular non-encircling cord locating structure in order to protect the spermatic cord and that it is interposed between the conjoined tendon and the inguinal ligament in such a way as to repair the hernia and at the same time to reconstitute the physiology of the inguinal canal.

Ibrid operation
Ibrid operation consists of the use of pure tissue (modifi ed Bassini) and NM.
The NM is interposed between the inguinal ligament and the conjoint tendon.

Operative technique
The lateral border of the narrow mesh is sutured in a The vacuum was fi lled in the early 80's by Lichtenstein [1], who developed a tension free inguinal hernia repair using a Polypropylene (PP) mesh to bridge the gap forming the hernia defect. In this way the patient's tissues are not 'stretched' over the defect, thus allowing the tissue to remain tension-free.
Recurrences were drastically reduced but a foreign body was inserted into the inguinal canal and the necessity of creating a key-hole to accomodate the spermatic cord caused a constriction of the spermatic cord itself.
Moreover literature data showed that, despite a low learning curve, surgeons were far from reaching the good results reported by the Lichtenstein [1] and continued to experience high recurrences.
To overcome the problem, surgeons demanded for larger and always more complex meshes in the erroneous judgment that a such a mesh could provide further strength to the repair.
Recent studies show that this attitude did not change the rate of recurrence at all.
For this reason many Authors are beginning to question the real effi cacy of the mesh repair, especially at the light of the high incidence of chronic inguinal pain [2,3].
The pure tissue repair has in fact the advantage of restoring the physiology of the inguinal canal with only a little increase in the recurrence rate, and the advantage of no putting any foreign body in the inguinal canal, thus reducing the meshrelated complications, especially postoperative chronic inguinodynia.
In order to maintain the advantages of both techniques, the modifi ed Bassini operation and mesh repair according to Lichtenstein, we created an improved implantable inguinal mesh (Figure 1) 6×2.5 centimeters in size having a lateral nonencircling cord locating structure to protect the spermatic cord and it is confi gured in such a way as to reconstitute the physiologic structure of the inguinal canal into the prehernia state.
Such a confi guration and structure allow the use of patient's original tissues to protect the spermatic cord structures from damage, so that both, the NM and the patient's tissues, may achieve the complete cure of the inguinal hernia and the reconstitution of the pre-hernia physiology. The NM, due to its innovative shape, has in fact two complementary actions in repairing the inguinal hernia.
First, it allows the native tissues (conjoint tendon) to be repositioned mostly at the original anatomical location so that the physiology of the inguinal canal is restored, and second reduces the tension on the suture line simply by increasing the height of the inguinal ligament in order to make easier the coaptation of the conjoint tendon to the neo-inguinal ligament that is the medial border of the narrow mesh.
Furthermore, the reduced dimension and volume of the mesh and the absence of the key hole encircling the spermatic cord are a protection factor for the cord, that will not be strangulated by its surrounding mesh with its fi brous transformation.
Essentially, the use of the NM may be considered as a The newly reconstructed posterior wall of the inguinal canal and the internal inguinal ring are formed by muscles, the conjoint tendon, so that the physiology of the inguinal canal, the shutter mechanism, is restored.
As the physiology is restored, the cure is to be expected.
The small in size NM does not encircle the spermatic cord, it does not bridge the defect but it approximates tissues.
It protects the spermatic cord and it is instrumental in preventing chronic inguinodynia.
The shrinking of the mesh, up to 60%, is not a disadvantage in this case, but it has the advantage of further approximation of the conjoint tendon to the native inguinal ligament preserving and enhancing the physiology of the shutter mechanism.

Conclusion
Clinical studies are warranted to evaluate the proposed claims of effi cacy and safety and the prospective of a better outcome of the use of the Narrow Mesh (NM) for the repair of inguinal hernia.