Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_633_Библиотеки_им_академика_М_И_Перельмана.pdf
Transversalis
Iliac vessels
310
fascia
Pectineal
ligament
Fig. 20.5 Suture repair femoral hernia preperitoneal approach, right
groin. The transversalis fascia is sutured to the pectineal ligament
Tips and Pitfalls
It is of great importance that a full dissection of the space is
carried out. The entire myopectineal orifice should be fully
visualized and the dissected space large enough to allow for
a sufficient overlap of the mesh. The peritoneum needs to be
mobilized especially in the lower aspect where incomplete
mobilization may lead to a part of the peritoneum finding its
way in between the mesh and the pelvic floor, leading to a
recurrence.
It is also important to pay close attention to the repair of
the abdominal wall to prevent the occurrence of an incisional
hernia; suturing of the incision in the fascia needs to be thorough, and in mesh repair, the mesh should cover the
incision.
When the hernia is not easily reduced, care must be taken
not to try to widen the hernia defect in the lateral direction,
due to the risk for injury to the femoral vein.
Femoral Approach
The infra-inguinal approach may allow for less tissue dissection since it is a fairly direct approach, leading the surgeon
straight to the hernia sac. It is not appropriate for the emergency hernia since it provides limited access to hernia content and site of strangulation.
The repair can either be performed using only suturing of
the femoral ring or using a plug to fill the femoral canal. The
suture repair has been associated with high recurrence rates.
Due to the relative simplicity of the approach, there are quite
a few smaller studies where single centers have used the
infra-inguinal plug method for femoral hernias and show fair
results, thus advocating use of the method [52–56].
Incision and Access
A transverse infra-inguinal incision is made and the subcutis
dissected to reveal the hernia sac. Sharp dissection is used
and electrocautery ensures hemostasis.
U. Dahlstrand
Fig. 20.6 Mobilized sac in femoral approach, left groin
Operative Steps
First, the hernia sac needs to be mobilized. The hernia
pushes the transversalis fascia and preperitoneal fat in
front of it. As the hernia meets the cribriform fascia of the
saphenous opening and the point where the femoral sheath
fuses into the fascia of the thigh, it often turns upward.
When the sac is to be mobilized, it is important to consider this.
Using sharp dissection, the fascial layers are to be completely dissected from the hernia sac, and the femoral ring
must be defined. The boundaries constituted by the inguinal
ligament (anterior) and the lacunar ligament (medial)
should first be identified and separated from the sac. Once
this is done, the sac can be lifted, allowing exposure of the
pectineus muscle and its origin on the superior ramus of the
pubic bone as well as the pectineal ligament. On the medial
side, electrocautery may be used; on the lateral side, which
is yet to be dissected, cold dissection is advisable. The femoral vein is covered by a fascial sheath that can make it
difficult to easily identify. Dissection should be kept close
to the hernia sac with fine dissecting scissors. The sac neck
should be isolated all the way up to the femoral ring
(Fig. 20.6).
The sac should be opened to inspect its content. If the
hernia content shows signs of ischemia, a change in approach
should be considered. The femoral approach does not provide good access. If the content is reduced, it is difficult to
observe if normal blood supply seems to be restituted. One
should definitely refrain from attempts to perform bowel
resection through the femoral opening.
Due to the often small defect, reduction of the hernia can
be difficult. An incision medially into the lacunar ligament
20 Femoral Hernia
311
a
b
Fig. 20.7 Closure of the sac at the neck, left groin
can be made in such instances. When the, non-strangulated,
hernia contents have been reduced successfully, the hernia
sac can be closed and excised (Fig. 20.7).
If a plug is used, it should be tailored to an appropriate
size. The plug can either be of the rolled type described by
Lichtenstein [57] or of the “umbrella” type (one constructed from a circular flat mesh or a preformed one)
[58]. The point of using a prosthetic plug is to obliterate
the opening of the canal without causing tension. When
the plug has been put into place within the femoral canal,
it is sutured to the medial, posterior, and anterior aspects.
It is not to be fixated laterally, in order to not risk injury to
the iliofemoral vein.
In a suture repair, the femoral ring is shut by means of a
suture. The femoral vein should be protected and retracted
laterally. The suture starts at the medial margin of the femoral vein (where it would be, were it not retracted) first going
through the pectineal ligament and then the inguinal ligament. If the suture is performed as a figure of eight, a knot
adjacent to the femoral vein can be avoided (Fig. 20.8).
c
Closure
After ensuring hemostasis, one or two absorbable interrupted
sutures are used to close the subcutis. The skin is closed with
a running intracutaneous suture.
Fig. 20.8 (a–c) Suture repair of a left-sided femoral hernia from the
femoral approach. The femoral vein is retracted laterally. The first
suture bite goes through the pectineal ligament. A figure-of-eight suture
between the pectineal ligament and the inguinal ligament is performed.
The knot is secured medially
312
U. Dahlstrand
Tips and Pitfalls
The method is not suited for patients where obstruction or
strangulation is suspected. It is difficult to ensure that you are
able to adequately assess hernia content.
While the approach leaves the inguinal area intact, it also
stops the surgeon from identifying an ipsilateral concomitant
inguinal hernia that could be repaired in the same session.
Combined hernias including a femoral component are not
uncommon, especially not in males with femoral herniation.
If a too large plug is used, it may obstruct the femoral
vein.
If the suture of the femoral ring is too tight upon the femoral vein, it may cause venous obstruction, while a suture
started too far from the vein may provide inadequate closure
and make the patient prone to recurrence.
Inguinal Approach
This open route provides a view that may be more familiar to
surgeons who are accustomed to repair of inguinal hernia.
The access to incarcerated hernia content is not as pronounced
as with the preperitoneal approach, and the approach is technically more demanding than the femoral approach.
Incision and Access
An incision is made parallel to the inguinal ligament, just as
for an inguinal repair. The subcutaneous tissue is dissected,
the external aponeurosis opened, and the transversalis fascia
is identified.
Operative Steps
The transversalis fascia is incised and the posterior wall of
the inguinal canal opened. The femoral hernia is identified.
After preparation of the neck, the hernia is reduced. If
needed, the lacunar ligament can be incised to make the
reduction easier. The neck of the sac is ligated and the sac
excised.
The repair can be performed with a flat preperitoneal
mesh, a mesh plug or by suture.
In the transinguinal preperitoneal technique, a flat mesh is
placed preperitoneally. The access is seldom as good as in
the preperitoneal techniques (open or laparoscopic). The
mesh should cover the entire myopectineal orifice though.
After placement of the mesh, the transversalis fascia and the
aponeurosis of the external oblique are closed using running
sutures.
In a plug repair, the plug is placed just like the plug in the
femoral approach, only from the cranial side of the inguinal
ligament. The plug is secured with multiple sutures. In order to
address the fact that the posterior wall of the inguinal canal
was opened up, a flat mesh can be placed between the transversalis fascia and the external oblique, as it would have been
if there was an inguinal hernia, as a preventive measure.
If a suture repair is performed, a nonabsorbable figure-ofeight suture is applied between the inguinal ligament and the
pectineal ligament.
Tips and Pitfalls
This approach engages the inguinal area, even if there is no
hernia there. The repair needs to take that into account and
minimize the risk for an (incisional) inguinal hernia. Placing
a flat mesh can be a solution, but it could also be argued that
several dissection planes are used without benefit and that
the method introduces larger amounts of foreign material
than actually needed.
In the suture technique, there is a risk for tissue tension,
and relaxing incision may be needed.
Conclusion
Femoral hernia is a rather uncommon but clinically impor-
tant entity. Its relative infrequency combined with its ten-
dency to present as an emergency makes it more difficult to
gather high-quality evidence regarding best practice.
Femoral hernias should be repaired electively when at
all possible. The largest studies available indicate that
preperitoneal mesh repairs render the best results with
regard to risk for recurrence.
It is paramount that strangulated femoral hernias are
identified as soon as possible. In patients who present
with abdominal pain and signs of intestinal obstruction or
strangulation, femoral hernia should always be suspected.
The physical examination of these patients should accordingly always include an assessment of the groin.
Acknowledgment This is an updated version of the chapter authored
by Patrick J. O’Dwyer. Patrick J. O’Dwyer has not participated in the
revision of this chapter for the fifth edition.
References
1. Moschcowitz AV. Prevascular femoral hernia. Ann Surg.
1912;55(6):848–56.
2. Stevens A. Health care needs assessment: the epidemiologically
based needs assessment reviews, vol. 1. Radcliffe; 2004.
3. Dahlstrand U, Wollert S, Nordin P, Sandblom G, Gunnarsson
U. Emergency femoral hernia repair: a study based on a national
register. Ann Surg. 2009;249(4):672–6. https://doi.org/10.1097/
SLA.0b013e31819ed943.
4. Bay-Nielsen M, Kehlet H, Strand L, Malmstrom J, Andersen F, Wara
P, et al. Quality assessment of 26,304 herniorrhaphies in Denmark:
a prospective nationwide study. Lancet. 2001;358(9288):1124–8.
https://doi.org/10.1016/s0140-6736(01)06251-1.
5. Glassow F. Femoral hernia. Review of 2,105 repairs in a 17 year
period. Am J Surg. 1985;150(3):353–6.
6. Putnis S, Wong A, Berney C. Synchronous femoral hernias diagnosed during endoscopic inguinal hernia repair. Surg Endosc.
2011;25(12):3752–4. https://doi.org/10.1007/s00464-011-1781-3.
20 Femoral Hernia
313
7. Rath A, Bhatia P, Kalhan S, John S, Khetan M, Bindal V, et al.
Endoscopic TEP inguinal hernia repair in the management of
occult obturator and femoral hernias. Surg Laparosc Endosc
Percutan Tech. 2014;24(4):375–7. https://doi.org/10.1097/
SLE.0b013e3182901509.
8. Andresen K, Bisgaard T, Kehlet H, Wara P, Rosenberg J. Reoperation
rates for laparoscopic vs open repair of femoral hernias in Denmark:
a nationwide analysis. JAMA Surg. 2014;149(8):853–7. https://doi.
org/10.1001/jamasurg.2014.177.
9. Swedish Hernia Register T. Annual report 2015, www.svenskt-
brackregister.se. 2016. http://www.svensktbrackregister.se/rapporter-71/verksamhetsberaettelser. Accessed Feb 25 2017.
10. Odula P, Kakande I. Femoral hernia at Mulago hospital. East
Central Afr J Surg. 2004;9(2):74–7.
11. Berliner SD, Burson LC, Wise L. The Henry operation for incarcerated and strangulated femoral hernias. Arch Surg. 1992;127(3):314–
6. discussion 6
12. McEvedy PG. Femoral hernia. Ann R Coll Surg Engl. 1950;
7(6):484–96.
13. Ludington LG. Femoral hernia and its management, with particular
reference to its occurrence following inguinal herniorrhaphy. Ann
Surg. 1958;148(5):823–6.
14. Burton CC, Bauer R. Femoral hernia; a review of 165 repairs. Ann
Surg. 1958;148(6):913–8.
15. Ponka JL, Brush BE. Problem of femoral hernia. Arch Surg.
1971;102(4):417–23.
16. Mikkelsen T, Bay-Nielsen M, Kehlet H. Risk of femoral hernia
after inguinal herniorrhaphy. Br J Surg. 2002;89(4):486–8. https://
doi.org/10.1046/j.0007-1323.2002.02058.x.
17. Burcharth J, Pedersen M, Bisgaard T, Pedersen C, Rosenberg
J. Nationwide prevalence of groin hernia repair. PLoS One.
2013;8(1):e54367. https://doi.org/10.1371/journal.pone.0054367.
18. Rosemar A, Angerås U, Rosengren A, Nordin P. Effect of body
mass index on groin hernia surgery. Ann Surg. 2010;252(2):397–
401. https://doi.org/10.1097/SLA.0b013e3181e985a1.
19. Hair A, Paterson C, O’Dwyer PJ. Diagnosis of a femoral hernia in
the elective setting. J R Coll Surg Edinb. 2001;46(2):117–8.
20. Robinson P, Hensor E, Lansdown MJ, Ambrose NS, Chapman
AH. Inguinofemoral hernia: accuracy of sonography in patients
with indeterminate clinical features. AJR Am J Roentgenol.
2006;187(5):1168–78. https://doi.org/10.2214/AJR.05.1251.
21. Bradley M, Morgan D, Pentlow B, Roe A. The groin hernia – an
ultrasound diagnosis? Ann R Coll Surg Engl. 2003;85(3):178–80.
https://doi.org/10.1308/003588403321661334.
22. Bradley M, Morgan J, Pentlow B, Roe A. The positive predictive
value of diagnostic ultrasound for occult herniae. Ann R Coll Surg
Engl. 2006;88(2):165–7. https://doi.org/10.1308/003588406X95110.
23. Djuric-Stefanovic A, Saranovic D, Ivanovic A, Masulovic D,
Zuvela M, Bjelovic M, et al. The accuracy of ultrasonography in
classification of groin hernias according to the criteria of the unified classification system. Hernia. 2008;12(4):395–400. https://doi.
org/10.1007/s10029-008-0352-6.
24. Corder AP. The diagnosis of femoral hernia. Postgrad Med J.
1992;68(795):26–8.
25. Nilsson H, Stylianidis G, Haapamaki M, Nilsson E,
Nordin P. Mortality after groin hernia surgery. Ann
Surg. 2007;245(4):656–60. https://doi.org/10.1097/01.
sla.0000251364.32698.4b. 00000658-200704000-00024 [pii]
26. Chamary VL. Femoral hernia: intestinal obstruction is an
unrecognized source of morbidity and mortality. Br J Surg.
1993;80(2):230–2.
27. Akinci M, Ergül Z, Kulah B, Yilmaz KB, Kulacoğlu H. Risk
factors related with unfavorable outcomes in groin hernia
repairs. Hernia. 2010;14(5):489–93. https://doi.org/10.1007/
s10029-010-0683-y.
28. Kurt N, Oncel M, Ozkan Z, Bingul S. Risk and outcome of bowel
resection in patients with incarcerated groin hernias: retrospective
study. World J Surg. 2003;27(6):741–3. https://doi.org/10.1007/
s00268-003-6826-x.
29. Roth N, Gangl O, Havlicek W, Függer R. The impact of emergency surgery on results of femoral hernia repair. Eur Surg.
2010;42(6):299–303. https://doi.org/10.1007/s10353-010-0573-7.
30. Dahlstrand U, Sandblom G, Wollert S, Gunnarsson U. Limited
potential for prevention of emergency surgery for femoral hernia. World J Surg. 2014;38(8):1931–6. https://doi.org/10.1007/
s00268-014-2539-6.
31. McEntee GP, O’Carroll A, Mooney B, Egan TJ, Delaney PV. Timing
of strangulation in adult hernias. Br J Surg. 1989;76(7):725–6.
32. Chan G, Chan C. Longterm results of a prospective study of 225
femoral hernia repairs: indications for tissue and mesh repair.
J Am Coll Surg. 2008;207(3):360–7. https://doi.org/10.1016/j.
jamcollsurg.2008.04.018.
33. Gallegos NC, Dawson J, Jarvis M, Hobsley M. Risk of strangulation in groin hernias. Br J Surg. 1991;78(10):1171–3.
34. Kulah B, Duzgun AP, Moran M, Kulacoglu IH, Ozmen MM,
Coskun F. Emergency hernia repairs in elderly patients. Am J Surg.
2001;182(5):455–9.
35. Alvarez JA, Baldonedo RF, Bear IG, Solis JA, Alvarez P, Jorge
JI. Incarcerated groin hernias in adults: presentation and outcome. Hernia. 2004;8(2):121–6. https://doi.org/10.1007/
s10029-003-0186-1.
36. Ge BJ, Huang Q, Liu LM, Bian HP, Fan YZ. Risk factors for
bowel resection and outcome in patients with incarcerated groin
hernias. Hernia. 2010;14(3):259–64. https://doi.org/10.1007/
s10029-009-0602-2.
37. Alimoglu O, Kaya B, Okan I, Dasiran F, Guzey D, Bas G, et al.
Femoral hernia: a review of 83 cases. Hernia. 2005;10(1):70–3.
https://doi.org/10.1007/s10029-005-0045-3.
38. Nicholson S, Keane TE, Devlin HB. Femoral hernia: an avoidable
source of surgical mortality. Br J Surg. 1990;77(3):307–8.
39. Nilsson H, Nilsson E, Angeras U, Nordin P. Mortality after groin
hernia surgery: delay of treatment and cause of death. Hernia.
2011;15(3):301–7. https://doi.org/10.1007/s10029-011-0782-4.
40. Kjaergaard J, Bay-Nielsen M, Kehlet H. Mortality following emergency groin hernia surgery in Denmark. Hernia. 2010;14(4):351–5.
https://doi.org/10.1007/s10029-010-0657-0.
41. Simons MP, Aufenacker T, Bay-Nielsen M, Bouillot JL, Campanelli
G, Conze J, et al. European hernia society guidelines on the treatment of inguinal hernia in adult patients. Hernia. 2009;13(4):343–
403. https://doi.org/10.1007/s10029-009-0529-7.
42. van den Heuvel B, Dwars BJ, Klassen DR, Bonjer HJ. Is surgical
repair of an asymptomatic groin hernia appropriate? A review. Hernia.
2011;15(3):251–9. https://doi.org/10.1007/s10029-011-0796-y.
43. Tingwald GR, Cooperman M. Inguinal and femoral hernia repair in
geriatric patients. Surg Gynecol Obstet. 1982;154(5):704–6.
44. Gianetta E, de Cian F, Cuneo S, Friedman D, Vitale B, Marinari
G, et al. Hernia repair in elderly patients. Br J Surg. 1997;
84(7):983–5.
45. Scott NW, McCormack K, Graham P, Go PM, Ross SJ, Grant
AM. Open mesh versus non-mesh for repair of femoral and inguinal hernia. Cochrane Database Syst Rev. 2002;4:CD002197.
https://doi.org/10.1002/14651858.CD002197.
46. Chen J, Lv Y, Shen Y, Liu S, Wang M. A prospective comparison of preperitoneal tension-free open herniorrhaphy with mesh
plug herniorrhaphy for the treatment of femoral hernias. Surgery.
2010;148(5):976–81. https://doi.org/10.1016/j.surg.2010.02.006.
47. Dahlstrand U, Sandblom G, Nordin P, Wollert S, Gunnarsson
U. Chronic pain after femoral hernia repair: a cross-sectional
study. Ann Surg. 2011;254(6):1017–21. https://doi.org/10.1097/
SLA.0b013e31822ba9b6.
314
U. Dahlstrand
48. Cox TC, Huntington CR, Blair LJ, Prasad T, Heniford BT,
Augenstein VA. Quality of life and outcomes for femoral hernia repair: does laparoscopy have an advantage? Hernia.
2017;21(1):79–88. https://doi.org/10.1007/s10029-016-1502-x.
49. Nyhus LM, Condon RE, Harkins HN. Clinical experiences with
preperitoneal hernial repair for all types of hernia of the groin, with
particular reference to the importance of transversalis fascia analogues. Am J Surg. 1960;100:234–44.
50. Henry A. Operation for femoral hernia by a midline extraperitoneal
approach. Lancet. 1936;227(5871):531–3. https://doi.org/10.1016/
S0140-6736(01)36573-X.
51. Smith WR, Moore EE, Osborn P, Agudelo JF, Morgan SJ, Parekh
AA, et al. Retroperitoneal packing as a resuscitation technique for
hemodynamically unstable patients with pelvic fractures: report of
two representative cases and a description of technique. J Trauma.
2005;59(6):1510–4.
52. Hachisuka T. Femoral hernia repair. Surg Clin North Am. 2003;
83(5):1189–205.
53. Sanchez-Bustos F, Ramia JM, Fernandez Ferrero F. Prosthetic
repair of femoral hernia: audit of long term follow-up.
Eur J Surg. 1998;164(3):191–3. https://doi.org/10.1080/
110241598750004634.
54. Song Y, Lu A, Ma D, Wang Y, Wu X, Lei W. Long-term results
of femoral hernia repair with ULTRAPRO plug. J Surg Res.
2015;194(2):383–7. https://doi.org/10.1016/j.jss.2014.10.058.
55. Allan SM, Heddle RM. Prolene plug repair for femoral hernia. Ann
R Coll Surg Engl. 1989;71(4):220–1.
56. Pangeni A, Shakya VC, Shrestha AR, Pandit R, Byanjankar B,
Rai S. Femoral hernia: reappraisal of low repair with the conical mesh plug. Hernia. 2017;21(1):73–7. https://doi.org/10.1007/
s10029-016-1500-z.
57. Lichtenstein IL, Shore JM. Simplified repair of femoral and
recurrent inguinal hernias by a “plug” technic. Am J Surg. 1974;
128(3):439–44.
58. Robbins AW, Rutkow IM. Mesh plug repair and groin hernia surgery. Surg Clin North Am. 1998;78(6):1007–23, vi–vii.
Inguinal Hernias in Babies and Children
R. Miller and S. Clarke
21
Introduction
A Brief History of Paediatric Inguinal Hernia Repair
A congenital inguinal hernia can be defined as a protrusion
of intra-abdominal contents through the deep inguinal ring.
The underlying abnormality leading to its development is a
patent processus vaginalis (PPV). This was described by
Galen in 176 AD as a ‘small off-shoot of the great peritoneal
sac in the lower abdomen’ which may result in a congenital
(indirect) inguinal hernia or hydrocele [1].
Initially the management of hernias was compression
strapping. However, the surgical management of inguinal hernias has been documented as far back as the Roman Celsus,
where removal of the hernial sac and testis through a scrotal
incision was recommended [1]. Testicle amputation was an
essential part of the surgical management of inguinal hernias
until it was rejected by William de Salicet (1210–1277).
The foundation of herniology was set during the
Renaissance. The greatest contributor was Pierre Franco, a
Swiss barber-surgeon, who in 1556 devised a technique to
allow division of the constricting facial ring without damage
to the bowel [2]. Ligation of the hernial sac at the external
inguinal ring was practised by Stromayr, who distinguished
between direct and indirect hernias and allowed removal of
the testis in the latter type, and by Purmann (1649–1711)
who spared the testicle [3, 4].
While Bassini, Halsted and Shouldice were describing
methods of repair and reinforcement in adult hernias, Turner,
R. Miller
Chelsea and Westminster Hospital, London, UK
e-mail: robmiller90@gmail.com
S. Clarke (
Department of Pediatric Surgery, Chelsea and Westminster
Hospital, London, UK
e-mail: Simon.Clarke@chelwest.nhs.uk
*)
in 1912, reported that in the majority of children, no repair
was required for the treatment of inguinal hernia and that
only high ligation of the sac was necessary [3].
Soon after the advent of laparoscopy for adult inguinal
hernias, laparoscopic repair in children gained popularity.
Shouldice and Lichtenstein repairs are still the most favoured
approaches for the treatment of groin hernias in adults [2],
but techniques for inguinal hernia repair in children continue
to evolve.
Embryology
The sex of an embryo is determined genetically and therefore present from the time of fertilisation. However, for the
first 6 weeks, the sex of the foetus is indeterminable. It is not
until approximately the seventh week that germ cells appear
at the urogenital ridge and the indifferent gonads develop the
morphological features of male or female. Both the urinary
and genital systems develop from mesoderm [5].
Towards the end of the second month, a cord of condensed
mesenchymal cells forms extending from the caudal pole of
the male gonad. This is known as the gubernaculum. As testicular descent starts, an extra-abdominal portion of gubernaculum forms, growing towards the scrotal swellings. The
inguinal canal forms around this gubernaculum as the muscles of the abdominal wall begin to differentiate. As the testis
moves through the inguinal ring, the gubernaculum contracts
and the testes will normally reach the scrotum by 33 weeks
[5]. In tandem but independent to this process is the bilateral
evagination of peritoneum either side of the midline. This
evagination forms the processus vaginalis (PV) and follows
the gubernaculum into the scrotum (Fig. 21.1). The PV
accompanies the muscular and fascial layers of the abdominal wall, which form the inguinal canal. Some researchers
have suggested that formation of the PV is a result of
intra- abdominal pressure, whereas others believe that it is an
active process [6].
© Springer International Publishing AG, part of Springer Nature 2018
K.A. LeBlanc et al. (eds.), Management of Abdominal Hernias, https://doi.org/10.1007/978-3-319-63251-3_21
315
316
R. Miller and S. Clarke
Fig. 21.1 Embryology of the processus vaginalis. T testicle, G gubernaculum, R rectum
It is important to note that the testis projects into the
reflected fold of the PV. It is not within the PV. In males, the
distal end of the PV, into which the testis projects, forms
the tunica vaginalis, and the proximal part, adjacent to the
spermatic cord, becomes obliterated leaving a fibrous remnant. This normally closes in the first year of life. If this
proximal part of the PV does not close, a congenital inguinal hernia may form. If the tract partially obliterates, a
hydrocele may form at the spermatic cord, testis or both
[5]. Within females, the same parietal peritoneal evagination occurs, accompanying the round ligament. This forms
the processus vaginalis within the inguinal canal, some-
times termed the canal of Nuck. This normally undergoes
complete obliteration. However, rarely, failure or incomplete obliteration can occur, causing an indirect hernia or
hydrocele in females [7].
It is unknown where the processus starts its closure: proximal, middle or distal parts [6], and the mechanisms govern-
ing PV obliteration are not fully understood. Some authors
believe that apoptosis of smooth muscle is pivotal for PV
closure and that the interplay of androgens and catecholaminergic activity governs this process [8, 9]. The importance of smooth muscle cells has also been highlighted in
indirect inguinal hernias in adult patients [10]. Other factors
thought to be important include hepatocyte growth factor
(HGF) and calcitonin gene-related peptide (CGRP). Studies
have shown that exogenous CGRP in cultured PV epithelial
cells causes fusion of a patent PV by epithelial mesenchymal
transformation, possible via HGF [11, 12].
The exact timing of closure is also uncertain. Studies suggest that most infants are born with a patent processus vaginalis [6] and that closure is most likely within the first year
of life [5]. After that, patency rates fall more gradually and
stabilise around 3–5 years of age. However, one study reports
that 22% of patients under the age of 20 years had a PPV,
dropping to 6% of those between 20 and 30 years [13].
a Normal
Vas
bc
21 Inguinal Hernias in Babies and Children
317
Anatomy
The basic anatomy of the inguinal canal is the same in children as in adults. However, there are some differences. In
infants and children, the inguinal canal is shorter in relation to
body size than in adults. In infants it is 1–1.5 cm long. The
internal and the external rings are nearly superimposed in
cases of pubic diastasis (bladder and cloacal exstrophy) or in
infants with very large inguinal hernias where the external
inguinal ring is very stretched. Finally, Scarpa’s fascia is
Peritoneal cavity
Obliterated processus
vaginalis
often more prominent in infants, so much so that the surgeon
may mistake it for the aponeurosis of the external oblique
muscle.
Aetiology
Failure of obliteration of the PV may result in a variety of
inguinoscrotal anomalies (Fig. 21.2).
These will include:
Tunica vaginalis
de f
Fig. 21.2 Inguinoscrotal variations of the processus vaginalis. Normally obliterated (a), indirect inguinoscrotal hernia (b), inguinal hernia (c),
communicating hydrocele (d), hydrocele of the tunica vaginalis (e), hydrocele of the cord (f)
318
R. Miller and S. Clarke
• Complete persistence resulting in an indirect inguinoscrotal hernia (Fig. 21.2b).
• Complete patency with a narrow opening at the internal
ring referred to as a communicating hydrocele (Fig. 21.2d).
• Distal processus obliteration and proximal hernia patency
resulting in an indirect inguinal hernia (Fig. 21.2c).
• Proximal obliteration with distal patency resulting in
hydrocele of the tunica vaginalis (noncommunicating
hydrocele). Its counterparts in girls are called a hydrocele
of the canal of Nuck (Fig. 21.2e).
• Proximal and distal obliteration with central patency
referred to as a hydrocele of the cord (Fig. 21.2f).
A patent processus vaginalis (PPV) is a prerequisite for
developing an indirect inguinal hernia but its patency alone
does not mean an inevitable hernia. Prematurity is one situation where the normal physiological processes of testicular
descent and PV closure are not complete, hence the high
incidence of inguinal hernia. A positive family history and
other factors (Table 21.1) have also been shown to be associated with inguinal hernia in children. A link between inguinal hernia and some genetic diseases (viz. connective tissue
disorders) is also documented [14].
Incidence
The percentage of children with inguinal hernia is reported
to be around 5% [1]. This incidence rises in premature
infants, and reported ranges vary from 11% [3] to 25% [1].
Boys are three to ten times more commonly affected than
girls [1, 6]. In a recent study of 79, 794 Taiwanese children
under 15 years of age, the cumulative incidence of inguinal
hernias in boys was 6.62% vs. 0.74% in girls [15]. In addition, age at presentation is significantly younger in males
[16]. 85–90% of hernias are reportedly unilateral [4, 16, 17]
or 5.54:1, bilateral/unilateral [15]. Consistently, approximately 60% of inguinal hernias are right sided [4, 16].
However, less consistently is the distribution of left and bilateral hernias. Approximately 18–30% of inguinal hernias
occur on the left side and the remaining 10–24% are bilateral
at presentation [4, 16]. This weighting to right-sided hernias
is attributed to later testicular descent and delayed obliteration of the processus vaginalis on the right [1, 4, 18]. In girls,
this observation cannot be explained by the same mechanism
of testicular descent, and the cause remains obscure. An
inguinal hernia in a girl should not be taken at face value, and
the surgeon should always have a suspicion of complete
androgen insensitivity syndrome (CAIS) [19] and take the
appropriate measures for preoperative and intraoperative
investigations. The incidence of inguinal hernias is higher in
both preterm and low birth weight infants. The incidence in
low birth weight infants is reported to be around 16% [20,
21]. Within this group, bilateral hernias appear to be more
common than unilateral, with up to 60% being bilateral [17,
21]. There is a positive family history in 11.5% of patients
[22], with an increased incidence in twins (10.6% in male
twins and 4.1% in female twins) [6].
Presentation, Diagnosis and Differentials
Table 21.1 Predisposing factors to inguinal hernia in children
Age (prematurity)
Family history
Urogenital
Undescended testis
Pubic diastasis
Increased intra-abdominal pressure
Repair of exomphalos or gastroschisis
Ascites
Ventriculo-peritoneal shunt
Peritoneal dialysis
Meconium peritonitis
Chronic respiratory disease
Cystic fibrosis
Connective tissue disorders
Congenital hip dislocation
Ehlers–Danlos syndrome
Hunter–Hurler syndrome
Marfan’s syndrome
Mucopolysaccharidosis
The typical presenting history of an inguinal hernia is intermittent swelling in the groin in the region of the external
inguinal ring, scrotum or labia. As with many childhood conditions, this is usually first noticed by the carer. Parents might
notice it during bathing or when the child is crying and will
often reliably point to this area when prompted. Alternatively,
a paediatrician or general practitioner may find it on routine
examination.
Although physical examination will often be unremarkable, signs can be observed to support the diagnosis. To complete an examination, the child or infant should be placed
supine and undressed on an examining table in a warm room
with a chaperone present. After inspection of the groin for
any visible mass or asymmetry, the testis should be localised
in the scrotum to account for both testes and distinguish true
inguinal swellings from retractile or undescended testes. If a
mass is still not apparent, the ‘silk scarf/glove sign’ may be
used to determine patency of the PV. This is performed by
laying two fingers over the spermatic cord slightly above the
level of the pubic tubercle. The fingers are lightly rolled over
the cord from side to side. A positive sign is when the fingers
21 Inguinal Hernias in Babies and Children
319
‘slide’ as the two surfaces of the PPV roll against each other
indicating patency. It should be compared with the ‘normal’
non-presenting side, bearing in mind that the child may have
bilateral inguinal hernias. This remains a somewhat subjective sign although accuracy of up to 91% from repeated
examination is reported [23]. In addition to this, increasing
the intra-abdominal pressure, through the child coughing,
laughing or crying, may be helpful to demonstrate the bulge
of a hernia.
It is important to remember that the first presentation may
be acutely with a complication. The child may present with
incarceration, strangulation or bowel obstruction. As in
adults, it is important to remember that any child presenting
with intestinal obstruction should have a thorough examination of the hernial orifices.
In most cases, the diagnosis of an inguinal hernia is a
clinical one and is sufficient for a paediatric surgeon to operate. Historically, investigations have not been necessary.
They can be employed in rare cases where diagnostic doubt
exists, in the assessment of the contralateral side or where
there is suspicion of hernia recurrence. For this, ultrasound
scanning (USS) has gained popularity over the past decade
(Fig. 21.3). It has the advantage of being rapid, non-invasive
and complication-free. Studies reported by Chen et al. [24]
and Erez et al. [25] concluded that ultrasound is a reliable
tool and may even be used for preoperative evaluation of the
contralateral groin in cases of unilateral hernia on clinical
examination. On USS, a normal inguinal canal was found
with an inguinal canal width of 3.6 ± 0.8 mm. Measurements
of 4.9 ± 1.1 mm were associated with a PPV, whereas measurements of 7.2 ± 2.0 mm or greater were associated with a
true hernia [25]. An accuracy of up to 91.7% has been
reported in the use of USS for preoperative detection of a
patient processus vaginalis on the contralateral side of a clinically diagnosed inguinal hernia [26]. In turn, the development rate of contralateral inguinal hernias after unilateral
herniorrhaphy was reduced from 10.2 to 1.5% with the use of
contralateral USS ± fixation [27, 28].
In the hands of an experienced sonographer, ultrasound is
equally useful in girls with unilateral or bilateral inguinal
hernias, in order to exclude CAIS [19], and in the assessment
and diagnosis of uterus and ovarian herniation [29].
If there is uncertainty regarding the diagnosis, differentials to consider in infants and children include a hydrocele,
hydrocele of the cord, an undescended testicle (cryptorchidism) or a lymph node (Table 21.2).
While the underlying cause for an inguinal hernia and
hydrocele is the same, differentiating the two is important
because it affects subsequent management. The history of a
hydrocele can be similar to an inguinal hernia. However, they
should be differentiated on physical examination with transillumination being the pathognomonic sign for a hydrocele. A
hydrocele usually masks the testis and therefore it is difficult
to palpate the testicle separately (remember that the testicle is
not within a hydrocele but projected into the tunica vaginalis,
which contains the fluid of a hydrocele). In contrast, the testis
is usually palpable separately from a hernia. However, a large
hydrocele in an infant may be difficult to distinguish from an
incarcerated hernia. Remember that, although rare, hydroceles can occur in females within the canal of Nuck [7].
For infants with a congenital hydrocele, the processus vaginalis usually closes with resolution of the hydrocele during the
first year of life. The recommended management is therefore
to avoid surgery during that period, unless a hernia cannot be
excluded. As discussed above, USS may be helpful if this is
the case. After 2 years of age, a hydrocele is unlikely to resolve
and should be operated upon. The recommended operation is
high ligation of the processus vaginalis, as for inguinal hernia,
with drainage of the distal sac. Splitting, everting and removal
of the distal sac are not only unnecessary but may even cause
a post-operative haematoma. Fluid rarely reaccumulates, and
if it does, it usually resolves spontaneously. Although theoretically possible due to incomplete obliteration of the processus
vaginalis, there is no evidence that a hydrocele progresses to
form a hernia. Occasionally, a previously unapparent hydrocele may present in an older child as a scrotal swelling. This
often presents during a viral illness.
Retractile or undescended testis may again have a similar
history of intermittent swelling in the scrotal region.
However, this should be easily differentiated on physical
examination whereupon there would be failure to localise the
testicle within the hemi-scrotum and the scrotal sack may be
underdeveloped.
Fig. 21.3 Ultrasound scan of inguinal canal with herniated bowel loop
in a child
Table 21.2 Differential diagnoses for a mass in the groin in children
and infants
Inguinal hernia ± incarceration/strangulation
Hydrocele
Hydrocele of the cord (hydrocele of the canal of Nuck)
Undescended/retractile testes
Lymph nodes