exploding the myths of hernia repair

Exploding the Myths of Hernia Repair

Irving L. Lichtenstein, MD, FACS, Los Angeles, California J. Manny Shore, MD, FACS, Los Angeles, California

Science can never be a closed book. It is like a tree, ever- ‘growing, ever reaching new heights. Occasionally the lower branches, no longer giving nourishment to the tree, slough off. We should not be ashamed to change our methods; rather we should be ashamed never to do so.

C. V. Chapin

Traditional methods of hernia repair have varied little since the first description by Bassini more than ninety years ago. In 1884, he performed the first true inguinal floor reconstruction. Five years later he documented a recurrence rate well under 10 per cent; there has been little recorded since to indicate marked improvement in these results. Newer concepts, modern materials, and recent experimental evidence invite reevaluation of established surgical tenets. Despite the certainty of iconoclastic criticism, it is time to challenge some of the myths surrounding hernia repair. This report is a critical analysis of ten key surgical principles that have been followed as dogma for so many decades.

1. The use of local arwtheela for ingutnal hernlorrhaphy requires special expertise and increases the length and difficulty of the operation.

Reluctance to perform hernia repair without the participation of an anesthesiologist is understandable. Although the initial experience with local anesthesia may appear cumbersome, the technic is readily mastered by attention to a few basic steps. Complete anesthesia is easily achieved by simple infiltration without resort to complex nerve blocks [I]. Confidence in the method is acquired after minimal experience. The benefits of reduced oper- ating room time and decreased risk to the patient are sufficiently rewarding to encourage wider adoption of this technic.

2. Normal anatomic planes should be reconstructed in ingulnal hernia repair: transversalis fascia is the key layer.

Why should one attempt to reconstruct normal anatomy when the mere presence of a hernia has al-

From the Department of Surgery. Cedars of Lebanon-Mount Sinai Medical Center, Los Angeles, California.

Reprint requests should be addressed to Irving L. Lichtenstein. MD, 9201 Sunset Boulevard, Los Angeles. California 90069.

Volume 132, geptamber 1976

ready attested to the deficiency of the canal floor? The groin is the only area of the abdominal wall that is not supported by a musculotendinous barrier. This is unique to man who, in the evolutionary process, learned to walk upright, thus creating an abdominal “Achilles’ heel”-Hesselbach’s triangle-protected only by transversalis fascia.

The use of transversalis fascia for reconstruction of normal anatomy was an understandable outgrowth of investigations that examined the inguinal region from the preperitoneal aspect. (Figure 1.) This in- vited the conclusion that groin hernias could be cured by closing the defect in the transversalis fascia. Fascia, however, is merely connective tissue of little intrinsic strength and must be differentiated from collagen-rich aponeurosis. It is the latter which provides the true support to the abdominal wall.

Normally, increases in intra-abdominal pressure are counteracted in the groin by the shutter mechanism. This physiologic action approximates the arching fibers of the transversus abdominis tendon to the inguinal ligament during exertion; the weak transversalis fascia is thus reinforced. It is only when the buttressing action of this musculotendinous barrier fails that herniation occurs.

It is noteworthy that, since the time of Bassini, virtually all technics described incorporate the musculotendinous arch above the groin rather than relying solely on transversalis fascia. This produces a physiologic restoration rather than mere anatomic reconstruction of weak tissue, by constructing a strong new canal floor.

3. The superior pubic (Cooper’s) ligament is preferable to the inguinal (Poupart’s) ligament for herniorrhaphy.

A. The concept of restoring normal anatomy in- vited the use of Cooper’s ligament for inguinal herniorrhaphy since the transversalis fascia normally inserts there [2]. This anatomic rationale is weakened when the limited role of fascia in hernia repair is appreciated. Reliance on the tendon of the transversus abdominis, which does not insert on Cooper’s ligament, invites deviation from a strictly anatomic repair.

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Lichtenstein and Shore

B. Although Cooper’s ligament is stronger, it lacks the elasticity of the inguinal ligament. The latter, anchored at two fixed points, provides a mobile edge that imparts resiliency to the suture line during exertion. Conversely, sutures incorporating the un- yielding Cooper’s ligament may break or cut through tissue under tension.

The use of local anesthesia for inguinal herniorrhaphy permits dynamic observation of the reconstructed canal floor. Intra-operative testing of the transversus-Poupart’s approximation consistently demonstrates the gliding action of this suture line when stress is applied [3].

C. Cooper’s ligament lies at a greater distance from the lower edge of the transversus abdominis than does Poupart’s. (Figure 2.) This span is increased as Cooper’s ligament, which extends pos- terolaterally, approaches the femoral vein [4]. At this point, sutures incorporating this ligament are subject to maximum tension, predisposing to recurrence. (Figure 3.)

D. Because of the deeper course of Cooper’s ligament, exposure is limited, the operation is technically more difficult, and the hazard of serious femoral vein injury is increased.

It is apparent, therefore, that, despite the ac- knowledged strength of Cooper’s ligament, the se-

Figure 1. A, posterior rectus sheath. 6, linea semicircuiaris. C, transversus Bbdominis mu&e. 4 transversalis fascia ( cut a way). E, interfoveoiar ligament. F, inguinai ligament. 0, inferior epigastric vessels. H, spermatic vessels and nerve. I, iiiopsoas muscle. J, transversus abdominis aponeurosis. K, external iliac vein. L, transversalis fascia.. M, iacunar ligament. N, vas defer-ens. 0, superior pubic ligament.

(Reprinted with permission of publisher from [3]; redrawn from Netter FH: inguinai and remora1 hernias. New York, Ciba, 1955. )

lection of Poupart’s ligament for hernia repair offers many indispensable advantages.

4. Indirect hernias are congenital and high llgatlon of the sac suffices for cure: unlike direct hernias recurrences are mlnl- mal.

Copventional concepts of the etiology of groin hernias have recently been challenged. “The notion that factors other than the presence of a congenital patent peritoneal sac are responsible for some indirect inguinal hernias is supported by the observation that some indirect hernias do not appear until rela- tively late in life. In addition, analysis of autopsy and surgical statistical data suggests that as many as 20 per cent of males have a patent sac that persists well into adult years without the appharance of a typical inguinal hernia” 151. This unorthodox view is further supported by McVay’s experience; management of indirect inguinal hernias by high sac ligation ‘and reconstruction of the internal ring alone resulted in an unacceptably high recurrence rate of 5.5 per cent

[61. The hernia sac consists only of a single layer of

mesothelium. It is unreasonable to assign a crucial role to a structure of such insignificant strength in the genesis or repair of adult inguinal hernias. Although a patent processus vaginalis exists in all primates,

308 The American Journal of Surgery

Myths of Hernia Repair

~ ~--- SUBCUTANEOUS FAT

EXTERNAL OBLIQUE APONEUROSIS

INT. OBLIQUE MUSCLE

TRANSVERSUS AEDOMINIS APONEUROSIS

-. .__ PERITONEUM

- SPERMATIC CORD

--- TRANSVERSALIS FASCIA

- INGUINAL LIGAMENT

__ SUPERIOR PUElC LIGAMENT

.- PECTINEAL MUSCLE

PERIOR RAMUS OF BIC BONE

Figure 2. Sagittal sectton of the inguinai area. (Reprinted wfth petmfssion of puf&her from [3]; redrawn from Con&n RE: The anatomy of the inguinai regions. Hernia [ Nyhus LM Harkins HN, ed]. Philadelphia, JB Lippincott, 1964.)

man is the only animal prone to herniation; coexis- tence of fascial deficiency must therefore be a pre- requisite before clinical protrusion appears.

Since tissue insufficiency can occur on either side of the epigastric vessels, it is not surprising that the incidence of indirect and direct hernias in the adult is approximately equal. Interestingly, 50 per cent of all recurrences in carefully documented series are of the indirect variety. (Table I.) These findings do not support the concept that simple sac ligation and internal ring reconstruction are all that is indicated in indirect hernia repair. It is convenient to speculate that the original surgeon missed the sac, a fact ap- parently substantiated by the presence of a peritoneal sac in all indirect recurrences. However, Peacock and Madden [7] have shown that a fascial defect al- ways precedes peritoneal protrusion: “In no instance was a leading point of finger of peritoneum invading fascia before the fascia actually disappeared. These

TABLE I Hernia Recurrence

Figure 3. Lotheissen, McVay repair. A, external oblique aponeurosis. B, internal oblique muscle. C, transversus abdomfn& muscle and aponeurosts. D, transvet??alfs fascia. E, perftoneum. (Reprinted wfth permkston of pubtkher fivm

131.1

findings suggest that peritoneum in recurrent hernias is nothing more than ‘a passive space filler . . . .”

Final confirmation of this concept has been established in our recent clinical study. Since 1969, high ligation and excision of the sac has been abandoned in the repair of all indirect inguinal hernias in adults. The sac is opened and dissected from the cord; after reduction of its contents, it is simply replaced within the peritoneal cavity without excision or ligation. The repair then depends solely on the single layer approximation of transversus abdominis to Poupart’s ligament. (Figures 4, 5, and 6.) With this technic, there have been no recurrences in 460 consecutive primary indirect herniorrhaphies. We are in complete agreement with Glassow [8] who stated in a study embracing 18,400 indirect hernia repairs: “High ligation of an indirect hernial sac at the internal ring is traditional in both the training and practice of the abdominal surgeon. Nevertheless, with due respect to this long-established and almost hallowed concept, our experience here suggests that this is not neces- sarily of sole or even paramount importance in dealing with the indirect hernial sac.”

1 to 5 Years Type of Recurrence

Authors

Quillinan [13]

Thieme [ 141

Halverson and McVay [6]

Welsh [15]

Postoperatively

25%

29%

Postoperatively Postoperatively

50% 50%

60% 40%

62% 38%

50% 50%

Direct

50%

5 1%

50%

50%

indirect

50%

49%

50%

50%

Volume 132, September 1976 309


Figure 4. Transversus abdominis aponeurotic curtain. A, internal oblique muscle. 6, rectus sheath. C, transvenrus abdominis aponeurosis. The internal oblique muscle is ei- evated as it arches over the internal ring. l?ds exposes the transversus aponeurosls. (Reprinted with permission of publisher from [3 1. )

Figure 6. A, extemai oblique aponeumsis. B, intemaiobi~e mu&e. C, transvetsus ab&minis muscie and aptnmumsk D, transversalis fascia. E, peritoneum. (Reprinted with permission of publisher from [3]. )

5. The use of “conjoined tendon” Is essential for repair of direct hernias; a suture lateral to the cord (Coley’s suture) Is advisable for Indirect lngulnal hernlorrhaphy.

The term “conjoined tendon” commonly refers to the fibers of the internal oblique and transversus abdominis as they arch over the inguinal canal. Most authors describing the technic of inguinal herniorrhaphy recommend the use of this structure for reconstruction of the posterior canal floor. Meticulous anatomic dissections, however, have revealed that a true “conjoined tendon” rarely exists: in over 95 per

Figure 5. Approximation of the transversus abdominis to Poupart’s itgament provides an inpenetrable aponeurotic barrier. (Reprinted with permission of publisher from

L31.1

cent of cases, the internal oblique is muscular until it reaches the anterior rectus sheath. (Figure 7.) There is only one tendinous structure above the canal-the transversus abdominis-whose fibers are aponeurotic from the internal ring to the pubis. (Figure 8.) It is upon the strength of this structure that the integrity of all hernia repairs must de- pend.

Man’s vulnerable inguinal canal is protected by a strong guard first described by Cooper in 1807. It consists inferiorly of Poupart’s ligament, a structure unique to man, and superiorly of the combined internal oblique and transversus abdominis. When relaxed, there is an interval between these muscles and the inguinal ligament supported only by the thin transversalis fascia. (Figure 9.) During exertion, these muscles approximate Poupart’s ligament, closing the gap and providing a protective barrier to the inguinal floor. This is the shutter mechanism which normally reinforces the weakened anatomic area created by man’s upright position.

At the internal ring this action serves as a sphincter preventing herniation at this vulnerable site. This has been repeatedly demonstrated during herniorrhaphy under local anesthesia when the patient performs the Valsalva maneuver [9]. The addition of a suture lateral to the cord abolishes this physiologic action by immobilizing these structures. “Coley’s stitch” 191, since it must of necessity include muscle, may cut through during contraction, leaving an enlarged in-

310 The Amerkan Journal of fkrgety


A

FIgwe 7. A, internal obiique muscle. B, i&Ma/ ktx. C, refiected if@nai itgament. 0, externai spumatk fascia. E, exterd Mtque aponewosis. F, transvemus aMomh#s aponeurosis. G, deep ep&strk vesseis. U, trensversaik fascia. ( Reprin@d wttb permtssion oi publisher from [3]; redrawn tmm Netter FH: in- pdnai and femoral hernias. New York, CJba, 1955. )

Figure 8. A, extemai obiique muscie. B, intemai obi&e mu&e. C, tramdtkn ot transverqus abdominis mu&e to apneu~fs. 4 &P ePi#W- vessek- E, trm fssch. B&tom two iines indicate the spemWk cord and the external ingwinal ring. (Reprinted wfth permkskn of pub&her from [3]; redrawn from Burten: L4aments of the groin. Surgery 3 1: 565, 1952. )

B-

C-

D --


Flgure 9. The cremaster bundles along&k? the cord have beenllgatedandexcked.lnthedhekt’s&awtng thelno&ect hemlal sac has been removed. ( Rep&ted wlth permlsshm of publisher from [ 31. )

ternal ring and further predisposing to recurrent herniation.

Finally, our own extensive experience supports this concept, since the majority of indirect recurrences encountered followed the use of a lateral suture at the original operation. (Figure 10.)

6. lmlwlcatlon d thaw augments the strength of twnla rapak.

In 1898, William Mayo first described the imbrication operation often referred to as the “vest over pants technic.” This did indeed improve results for umbilical hemiorrhaphy and was quickly adopted for the repairs of all hernias. However, the success of this operation was actually due to the introduction of a transverse closure and not to the overlapping of tissue.

The vertical repair in vogue before Mayo’s description failed for two reasons: (1) Because of the direction of muscle pull, the margins of a vertical detect distract with increased intra-abdominal pressure, while the edges of a transverse opening tend to approximate. (2) Sutures for repair of a vertical defect are placed parallel to the direction of the fibers; tension causes tissue splitting, thus decreasing wound strength. (Figure 11.)

Experimental evidence from our laboratories, confirmed by others, demonstrated that simple approximation of wound edges was significantly stronger than overlapping of tissue [ 101. Early in our experience, these considerations led us to abandon imbrication in the repair of all abdominal wall hernias, without compromising the results.

Figure 10. The suture at the Internal ring extends beyond the medlal border, thus dlsplaclng the cord far laterally; however, “Coley’s stitch” Is never employed. (Reprlnted wlth permtsslon of publisher from [ 31. )

7. Wound lntecllon IE tlw comm~19~I cau80 ol recurrwce; since nonabso&abIa sutures and foreign body screens perpetuab wound sepsis, they musl ba avolded.

It is generally held that infection plays a major role in the genesis of recurrence after herniorrhaphy. Although recurrence rates varying from 5 to 10 per cent are usually reported, 95 per cent of these are due to causes other than sepsis. When infection does su- pervene in the presence of nonabsorbable sutures, the most troublesome sequela is the occasional draining sinus. However, sepsis after herniorrhaphy is ordi- narily superficial and rarely leads to recurrence.

With the introduction of catgut, surgeons eagerly adopted a suture that promised to eliminate wound sinuses. Unfortunately, absorbable sutures (in vivo) lose their tensile strength within one month. At this point, wound healing has contributed merely 30 per cent of normal tissue integrity. This increases to only 40 per cent by the end of two months [II]. With the loss of continuing suture support, the repair is left vulnerable to early recurrence. Wound integrity in the early postoperative period, therefore, requires reliance on strong nonabsorbable sutures.

Follow-up studies have shown that the vast majority of recurrences appear after the first postoperative year. (Table I.) These late recurrences cannot be attributed to technical error alone. The same dynamic forces that led to herniation initially remain operative and may eventuate in late recurrence due to tissue attrition.

A prosthetic screen, buttressing the repair (Figure l2), provides permanent reinforcement by stimu- lating the ingrowth of strong fibrous tissue. Because



polypropylene mesh is monofilamented, sepsis is well tolerated and infected wounds will usually heal without removal of the screen [12].

A significant reduction in the recurrence rate after herniorrhaphy can be anticipated with the routine use of nonabsorbable sutures and the increased ap- plication of prosthetic mesh reinforcement.

8. Restrlction of physlcal activity is eseentlal after hernlorfia- phy.

The practice of limiting postoperative activity is based on the concept that fresh wounds lack suffi- cient integrity to withstand stress until “they heal.” The ability of the repair to tolerate forces normally encountered in the postoperative period, such as vomiting and coughing, indicates the presence of significant wound strength immediately after sur-

gery. Contrary to traditional teaching, recent experi-

mental studies have shown that the surgical wound derives little strength from the healing process [JO]. Controlled observations reveal that nonabsorbable sutures immediately impart 70 per cent of normal tissue strength to the freshly sutured incision. This support is maintained indefinitely and is indepen- dent of wound healing, which restores only 40 per cent of normal tissue integrity by the end of two months. (Figure 13.) These observations indicate that

Figure If. Transverse versus vertical incision. A, intra- abdominal tension decreases apetiure of transverse incision. B, pi/cation of fibers in transverse repair. C, intra- abdominal tension separates edges of vertical incision. D, shearing or spiitting of fibers in vertical repair. ( Reprinted with permission of pub&her fmm [3]; redrawn from Kozaii DD: incisionai Hernia. Hernia [ Nyhus LM, Harkins HN, ed]. Philadelphia, Lippincott, 1964. )

tissue and suture strength are the only factors responsible for wound integrity in the early postoperative period and provide the physiologic rationale for permitting unrestricted physical exertion after sur-

gery. In our series of over 2,000 patients undergoing

primary hernia repair during the past fifteen years,

Figure 12. The screen is tacked over the suture line a##mximat@ the transvemus ab&mMs to PollPart’s iigament. ( t%@nted with permission of pub&her from [3]. )

Volume 132, !%ptembef 1976


I 5 40

z E 30

IiJ 20 0 SUTURES INTACT

0 SUTURES REMOVED

IO

0

0 i 8 12 16 20 24 28 32 36 40 44 48 52 56 60

POSTOPERATIVE DAYS

Figure 13. Wound strength compared with norm& tissue. With stitufes removed from the inciskn before testing, a typkai wound healing curve is obtained (rower Ike). ( Reprinted with permisskn of pubiisher from [lo]. )

only 0.9 per cent have recurred despite immediate postoperative resumption of normal activity [II 1.

8. Mart recurr~os war wtthln two your.

Published figures reveal a consistently high recurrence rate of 5 to 10 per cent after primary hernia repair. Table I indicates that only 25 per cent of these recur within the first postoperative year, whereas 50 per cent do not appear until more than five years later [6,13,14,15]. All investigators agree that the recurrence rate varies directly with the length of follow-up.

Why should hernias continue to recur? Peacock and Madden [7] have suggested that recurrences after six months are due to factors other than technical error or selection of an inferior procedure. They conclude that late recurrence is due to “decreased collagen synthesis or increased collagen degradation. Whatever the cause, the end result is attenuation. . . of fascia.”

Prevention of late recurrence thus clearly requires supplementing the basic repair with additional support. (Figure 14.) For this purpose, a prosthetic mesh is preferable to fascia because of its durability and ready availability without resort to additional surgery. Halverson and McVay [6] state: “It is en- tirely possible that our overall recurrence rate would have been less had we reinforced some of the quea- tionable cases with a sheet of marlex mesh. . . . Per- haps we shall liberalize our indications for its use.”

In our study, the routine use of a prosthetic mesh to buttress all direct and recurrent herniorrhaphies has not increased the morbidity while providing significant protection against late recurrence.

Figure 14. The repair is reinforced with a prosthetic mesh screen. (Reprinted with permission of publisher from

131.)

10. Surgeon8 are gemrslty aware of their results.

Well trained surgeons, having learned a particular operative technic, believe they have good results and are loathe to change. With understandable loyalty and pride, they may defend a procedure mastered years before. However, faith in any particular technic is not warranted without “long-term follow-up to demonstrate the effectiveness of the recommended procedures. The assumption that there are few (hernia) recurrences is fallacious for several reasons. First, unless the surgeon reexamines his patient pe- riodically, he is only guessing as to the recurrence rate of his patients. Second, the presumption that the patient who does not return is not having trouble with recurrence is wishful thinking, since many patients with a recurrence will seek ‘more skilled’ help for the second operation. Third, over a period of ten to twenty years, many patients change their geo- graphic area of residence and are lost to follow-up. Fourth, a follow-up of three to five years is totally inadequate to determine a recurrence rate . . . . Therefore, any short-term study of results from a given technic of hernioplasty is hardly valid” [6].

Excellent follow-up, while essential, places ex- traordinary demands on a busy surgical practice. Facts are apt to be clouded by impressions and figures replaced by estimates. Long-term studies en- compassing thousands of cases lend themselves ideally to data processing. Several years ago, in an attempt to resolve the many unanswered questions regarding herniorrhaphy, we programmed the subject for computerization. (Figure 15.) This method has proved invaluable in accurately docu- menting and analyzing the many variables involved.



Figure 15. Computer questionnaire for patient hernia StatkWs. I. 48 6 O,hCr

To date, 97 per cent follow-up has been achieved in this ongoing study. Long-term results will be reported after a further period of observation.

Summary

Sacred principles guiding surgical repair of groin hernias have remained basically unaltered since their inception. This may explain the failure of results to improve significantly over the years. Ten hallowed concepts have been critically analyzed in the light of modern technology and contemporary experience. Although challenging established surgical traditions invariably invites debate, it is essential to scientific progress.

References

1. Lichtenstein IL: Local anesthesia for herniopiasty. Calif Med 100: 108,1984.

2. McVay CV, Chapp JD: inguinai and femoral herniopiasty. Ann Surg 148: 499. 1958.

3.

4.

5.

8.

7.

8.

9. 10.

11.

12.

13.

SURGERY

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FOLLOW-UP

IN EACH CATEGORY

Encircle no more numbers

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IRVING LICHTENSTEIN, M.D.

274.3173

Lichtenstein IL: Hernia Repair without Disability. St. Louis, CV Mosby, 1970.

Lichtenstein IL, Shore JM: Simplified repair of femoral and recurrent inguinai hernias by a “plug” technic. Am J Surg 128: 439,1974.

Conner WT, Peacock EE Jr: Some studies on the etiology of inguinai hernia. Am J Surg 128: 732, 1973.

Halverson K, McVay CS: inguinai and femcral hemioptasty. Arch Surg 101: 127, 1970.

Peacock EE Jr, Madden JW: Studies on the biology and treat- ment of recurrent inguinai hernia. Personal communication, 1975.

Giassow F: High ligation of the sac in indirect inguinai hernia. Am J Surg 109: 480, 1985.

Coiey WB: Hernia. Philadelphia, WB Saunders, 1910. Lichtenstein IL, Herzikoff S, Shore JM, Jiron MW, Stuart S,

Mizuno L: The dynamics of wound healing. Surg Gyneco/ Obstet 130: 885, 1970.

Lichtenstein IL: immediate ambulation and return to work fol- lowing hernionhaphy. Ind Med Swg 35: 754, 1988.

Gilsdorf RB, Shea MM: Repair of massive septic abdominal wail defects with mariex mesh. Am J Surg 130: 834. 1975.

Cuiiiinan RH: Repair of rerxrent inguinal hsmii. Am J Swg 118: 593: 1989.

14. Thieme ST: Recurrent inguinai hernia. Arch Surg 103: 238, 1971.

15. Welsh D: Personal communication. Shouldice Clinic, Toronto, Canada. 1975.

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exploding the myths of hernia repair

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