Individual
features of hernias
Inguinal
hernia
Surgical
anatomy
The superficial inguinal ring is a triangular aperture in the
aponeurosis of the external oblique and lies 1.25 cm above the pubic tubercle.
The ring is bounded by a superomedial and an inferolateral crus joined by the
criss-cross intercrural fibres. Normally, the ring will not admit the tip of the
little finger.
The
deep inguinal ring is a U-shaped condensation of the transversalis fascia
and it lies 1.25 cm above the inguinal (Poupart’s) ligament, midway between
the symphysis pubis and the anterior superior iliac spine. The transversalis
fascia is the fascial envelope of the abdomen and the competency of the deep
inguinal ring depends on the integrity of this fascia.
The
inguinal canal. In infants the superficial and deep inguinal rings are almost
superimposed and the obliquity of the canal is slight. In adults the inguinal
canal, which is 3.75 cm long, is directed downwards and medially from the
deep to the superficial inguinal ring. In the male the inguinal canal transmits
the spermatic cord, the ilio-inguinal nerve and the genital branch of the
genitofemoral nerve. In the female the round ligament replaces the spermatic
cord.
Boundaries
of the canal. Figure 62.4 illustrates the canal, viewing the structures from
superficial to deep as is seen at operation. The anterior boundary
comprises mainly the external oblique aponeurosis with the conjoined muscle
laterally. The posterior boundary is formed by the fascia transversalis
and the conjoined tendon (internal oblique and transversus abdominus medially).
The inferior epigastric vessels lie posteriorly and medially to the deep
inguinal ring.
The superior boundary is formed by the conjoined muscles
(internal oblique and transversus) and the inferior boundary is the
inguinal ligament.
An
indirect hernia travels down the canal on the outer (lateral and anterior) side
of the spermatic cord. A direct hernia comes out directly forwards through the
posterior wall of the inguinal canal. While the neck of the indirect hernia is
lateral to the inferior epigastric vessels, the direct hernia usually emerges
medial to this except in the saddle-bag or pantaloon type, which has both a
lateral and a medial component. An inguinal hernia can be differentiated from a
femoral hernia by ascertaining the relation of the neck of the sac to the medial
end of the inguinal ligament and the pubic tubercle,
Indirect
(syn. oblique) inguinal hernia
This is the most common of all forms of hernia (see ‘Aetiology’). It is most common in the young, whereas a direct hernia is most common in the old. In the first decade of life inguinal hernia is more common on the right side in the male. This is no doubt associated with the later descent of the right testis and a higher incidence of failure of closure of the processus vaginalis. In adult males, 65 per cent of inguinal hernias are indirect and 55 per cent are right-sided. The hernia is bilateral in 12 per cent of cases.Three types of indirect inguinal hernia occur (Fig 62.5)
BubonoceleWhen the hernias limited to the inguinal canal
Funicular
the processus vaginalis is closed just above the epididymis the content of
the sac can be felt separately from the testis, which lies below the hernia
• Complete (syn. scrotal) — a complete inguinal hernia is rarely present at birth but is commonly encountered in infancy. It also occurs in adolescence or adult life. The testis appears to lie within the lower part of the hernia.
Clinical
features
Occurring at any age, males are 20 times more commonly affected than
females. The patient complains of pain in the groin or pain referred to the
testicle when performing heavy work or taking strenuous exercise. When asked to
cough a small transient bulging may be seen and felt together with an expansile
impulse. When the sac is still limited to the inguinal canal, the bulge may be
better seen by observing the inguinal region from the side or even looking down
the abdominal wall while standing behind the respective shoulder of the patient.
As
an indirect inguinal hernia increases in size it becomes apparent when the
patient coughs and persists until reduced (Fig. 62.6). As time goes on the
hernia comes down as soon as the patient stands up. In large hernias there is a sensation of
weight, and dragging on the mesentery may produce epigastric pain. If the
contents of the sac are reducible, the inguinal canal will be found to be
commodious.
In
infants the swelling appears when the child cries. It can be translucent in
infancy and early childhood, but never in an adult. In girls an ovary may
prolapse into the sac.
Differential diagnosis in the male.
• A vaginal hydrocele (Fig. 62.7);
• an encysted hydrocele of the cord;
• spermatocele;
• a femoral hernia;
• an incompletely descended testis in the inguinal canal —
an inguinal hernia is often associated with this condition;
• a lipoma of the cord — this is often a difficult, but
unimportant, diagnosis. It is usually not settled until the parts are displayed
by operation.
NB. Examination using finger and thumb across the neck of the scrotum
will help to distinguish between a swelling of inguinal origin and one which is
entirely intrascrotal.
Differential
diagnosis in the female.
• A hydrocele of the canal of Nuck is
the commonest differential diagnostic problem;
• a femoral hernia.
Treatment
of indirect inguinal hernia
Operative
treatment. Operation is the treatment of choice. It must be remembered
that patients who have a bad cough from chronic bronchitis should not be denied
an operation, for these are the very people who are in danger of getting a
strangulated hernia. In adults, local, epidural or spinal, as well as general,
anaesthesia can be used.
Inguinal
herniotomy. This is the basic operation which entails dissecting out and opening
the hernial sac, reducing any contents, and then transfixing the neck of the sac
and removing the remainder. It is employed either by itself or as the first step
in a repair procedure (herniorrhaphy). By itself it is sufficient for the
treatment of hernia in infants, adolescents and young adults. Any attempts at
repair in such cases may, in fact, do more harm than good.
In
infants it is not necessary to open the canal, as the internal and external
rings are superimposed. Excellent results are obtained. The operation is usually
now performed as a day case unless there are additional medical or social
problems.
Herniotomy
and repair (herniorrhaphy). This operation consists of: (1) excision of the
hernial sac; plus (2) repair of the stretched internal inguinal ring and the
transversalis fascia; and (3) further reinforcement of the posterior wall of the
inguinal canal. (2) and (3) must be achieved without tension resulting in the
wound and various techniques exist to achieve this, e.g. Shouldice operation,
fascial flaps or polypropylene mesh implants.
Operative
procedures
1.
Excision of the hernial sac (adult herniotomy). An incision is
made in the skin and subcutaneous tissue 1.25 cm above and parallel to the
medial two-thirds of the inguinal ligament. In large irreducible hernias the
incision may be extended laterally or into the upper part of the scrotum. After
dividing the superficial fascia and securing haemostasis, the external oblique
aponeurosis and the superficial inguinal ring are identified. The external
oblique aponeurosis is incised in the line of its fibres and the structures
beneath are carefully separated from its deep surface before completing the
incision through the superficial inguinal ring. In this way, the ilio-inguinal
nerve is safeguarded. With the inguinal canal thus opened, the upper leaf of the
external oblique is separated from the internal oblique by blunt dissection. In
the same way, the lower leaf is separated from the contents of the inguinal
canal until the inner aspect of the inguinal ligament is seen. The cremasteric
muscle fibres may he divided longitudinally to display the spermatic cord, but
this is by no means essential.
Excision of the sac. The
indirect sac may be distinguished as a pearly white structure lying on the outer
side of the cord and, when the internal spermatic fascia has been incised
longitudinally, it can usually be dissected out and then opened between
haemostats.
Variations in
dissection.
If the sac is small, it can be freed in
tutu. If it is of the lung funicular or scrotal type, or is extremely
thickened and adherent, the fundus must not be sought, for in so doing the blood
supply to the testis may be compromised. The sac is freed within the inguinal
canal and divided circumferentially such that the fundus remains in the scrotum.
Care must be taken to avoid damage to the vas and spermatic artery when freeing
the sac posteriorly.
An adherent sac can be
separated from the cord by first injecting saline under the posterior wall from
within (hydrodissection). A similar tactic is employed when dissecting the
gossamer sac of infants and children.
Reduction of contents. Intestine
or omentum is returned to the peritoneal cavity. Omentum is often adherent to
the neck or fundus of the sac: if to the neck, it is freed, and if to the fundus
of a large sac. it may be transfixed, ligated and cut across at a suitable
point. The distal part of the omentum, like the distal part of a large scrotal
sac, can be left in situ (the fundus should, however, not be ligated).
Isolation and ligation of
the neck of the sac. Whatever type of
sac is encountered, it is necessary to free its neck by blunt dissection until
the parietal peritoneum can be seen on all sides. The dissection is only
considered complete when the extraperitoneal fat has been encountered and the
inferior epigastric vessels are seen on the medial side. It used to be
considered essential to open the sac to ensure that no bowel or omentum was
adherent to the neck. If the sac is obviously empty, it is sufficient simply to
reduce it, close the internal ring and perform a herniorrhaphy if required. If
the sac is opened, all contents should be reduced and the neck transfixed as
high as possible before excising the sac.
2. Repair of the transversalis
fascia and the internal ring. When the internal ring is weak and stretched, and
the transversalis is bulging, the repair should include a technique of narrowing
the deep ring, for example the Lyric method of narrowing the ring with lateral
displacement of the curd (Fig. 62.8) or the Shouldice method, whereby the ring
and fascia are incised and carefully separated from the deep inferior epigastric
vessels and extraperitoneal far before an overlapping repair (‘double
breasting’) of the lower flap behind the upper flap is performed. In the
classic Shouldice operation, a third and
3.
Reinforcement of the posterior
inguinal wall. This is achieved by suturing without tension between the
tendinous apuneurotic arch of internal oblique to the under surface of the
inguinal ligament and to the pubic tubercle (as described above in the Shouldice
operation) or by reinforcing the posterior wall of the canal with a prosthetic
mesh. Care is taken when suturing not to pick up the same tendinous bundle for
each suture. Suturing of muscle bundles is of no value. The suturing method
can include a rectus-relaxing incision (Halsred—Tanner). The Lichtenstein
tension-free herniaplasty involves placement of an approximately 16 x 8 cm
(tailored to the individual patient’s requirements) mesh as an extra lamina,
anterior to the posterior wall and overlapping it generously in all directions,
including medially over the pubic tubercle. Other historical techniques, which
should now be abandoned because of poor results, include overlapping the
external oblique behind the cord (making it lie subcutaneously). Special care
was needed to avoid excessive narrowing of the new external ring which could
jeopardise
the vascular supply to and the venous return from the testis.
4. Completion of operation. If desired, the cremasteric muscle can be reconstituted: the external oblique is directly sutured or overlapped leaving a new external ring which should accommodate the tip of a finger (Fig. 62.10).
A truss. A
truss may be used when operation is contraindicated or when operation is
refused. Its use should be mainly historical as there are
very few contraindications to surgery with today’s variety of
anaesthetic
Direct
inguinal hernia
In adult males, 35 per cent of inguinal hernias are direct. At
presentation, 12 per cent of patients will have a contralateral hernia in
addition and there is a four-fold increased risk of future development of
contralateral hernia if one is not present at the original presentation.
A
direct inguinal hernia is always acquired. The sac passes through a weakness or
defect of the transversalis fascia in the posterior wall of the inguinal canal.
In some cases the defect is small and is represented by a discrete defect in the
transversalis fascia, while in others there is a generalised bulge. Often the
patient has poor lower abdominal musculature, as shown by the presence of
elongated bulgings (Malgaigne’s bulges). Women practically never develop a
direct inguinal hernia (Brown). Predisposing factors are smoking, and occupations
that involve straining and heavy lifting. Damage to the ilio-inguinal nerve
(previous appendicectomy) is another cause, due to resulting weakness of the
conjoined tendon.
Direct hernias do not often attain a large size or descend into the scrotum (Fig. 62.11). In contrast to an indirect inguinal hernia, a direct inguinal hernia lies behind the spermatic cord. The sac is often smaller than the hernial mass would indicate, the protruding mass mainly consisting of extraperitoneal fat. As the neck of the sac is wide, direct inguinal hernias do not often strangulate.
Funicular direct inguinal hernia (syn. prevesical hernia). This is a
narrow-necked hernia with prevesical fat and a portion of the bladder that
protrudes through a small oval defect in the medial part of the conjoined muscle
just above the pubic tubercle. It occurs principally in elderly males and
occasionally becomes strangulated. Unless there are definite contraindications,
operation should always be advised.
Dual
(syn. saddle bag; pantaloon) hernia. This type of hernia consists of two sacs
which straddle the inferior epigastric artery, one sac being medial and the
other lateral to this vessel. The condition is not rare and is a cause of
recurrence, one of the sacs having been overlooked at the time of operation.
Operation
for direct hernia. The principles of repair of direct hernias are the same as
those of an indirect hernia with the exception that the hernia sac can usually
be simply inverted after the sac has been dissected free and the transversalis
fascia reconstructed in front of it. This reconstruction of the posterior wall
of the inguinal canal should be undertaken by the Shouldice repair or mesh
implant using the Lichtenstein technique (Figs 62.9 and
62.10). The darn
operation is no longer acceptable because of its high recurrence rate and slow
rehabilitation.
Strangulated
inguinal hernia
Pathological and clinical features are described earlier in this
chapter. Strangulation of an inguinal hernia occurs at any time during life and
in both sexes. Indirect inguinal hernias strangulate more commonly, the direct
variety not so often owing to the wide neck of the sac. Sometimes a hernia
strangulates on the first occasion that it descends; more often strangulation
occurs in patients who have worn a truss for a long time, and in those with a
partially reducible or irreducible hernia.
In
order of frequency, the constricting agent is: (a) the neck of the sac; (b) the
external inguinal ring in children; and (c), rarely, adhesions within the sac.
Contents
Usually,
the small intestine is involved in the strangulation; the next most
frequent is the omentum; sometimes both are involved. It is rare for the large intestine to become strangulated in
an inguinal hernia, even when the hernia is of the sliding variety.
Strangulation
during infancy
The incidence of strangulation is 4 per cent (Gross) and the ratio of
females to males is 5:1. More frequently the hernia is irreducible but not
strangulated. In most cases of strangulated inguinal hernia occurring in
female infants the content of the sac is an ovary or an ovary plus its fallopian
tube.
The treatment of strangulated hernia is by emergency operation (‘The
danger is in the delay not in the operation’, Sir Astley Paston Cooper).
Vigorous resuscitation with intravenous fluids, nasogastric aspiration and
antibiotics is essential, although operation should not be unduly delayed in
moribund patients. It is also advisable to empty the bladder, if necessary by
catheterisation.
Inguinal herniotomy for strangulation. An incision is made over the most
prominent part of the swelling. The external oblique aponeurosis is exposed and
the sac, with its coverings, is seen issuing from the superficial ring. In all
but very large hernias, it is possible to deliver the body and fundus of the sac
together with its coverings and (in the male) the testis on to the surface. Each
layer covering the anterior surface of the body of the sac near the fundus is
incised and, if possible, stripped off the sac. The sac is then incised and any
fluid, which may be highly infective, drained effectively. The external oblique
aponeurosis and the superficial inguinal ring are divided. A finger is then
passed into the opening in the sac and, employing the finger as a guide, the sac
is slit along its length. If the constriction lies at the superficial inguinal
ring, or within the canal, it is readily divided by this procedure. When the
constriction is at the deep ring, by applying haemostats to the cut edge of the
neck of the sac and drawing them downwards, and at the same rime retracting the
internal oblique upwards, it may be possible to continue slitting the sac over
the finger towards the point of constriction. When the constriction is too tight
to admit a finger, a grooved dissector is inserted and the neck of the sac is
divided with a knife in an upward and inward direction, i.e. parallel to the
inferior epigastric vessels, under vision. Once the constriction has been
divided, the strangulated contents can be drawn down. Devitalised omentum is
excised after being securely ligated. Viable intestine is returned to the
peritoneal cavity. Doubtfully viable and gangrenous intestine is excised by
localised resection. If the hernial sac is of moderate size and can be separated
easily from its coverings, it is excised and closed by a purse-string suture.
When the sac is large and adherent, much time is saved by cutting across the sac
as described earlier. Having tied or sutured the neck of the sac, a repair can
be made if the condition of the patient permits. In those circumstances where
the incision has been soiled or gangrenous bowel resected, prosthetic mesh is
best avoided, although some authorities have successfully unused polypropylene
mesh with antibiotic cover.
Conservative measures. These
are only indicated in infants. The child is given analgesias and placed in
gallow’s traction (the judgement of Solomon position). In 75 per cent
of cases reduction is effected and there
appears to be no danger of gangrenous intestine being reduced (Irvine
Smith).
NB.
Vigorous manipulation (taxis) has no place in modern surgery and is
mentioned only to be condemned. Its dangers include:
• contusion or rupture of the intestinal wall;
• reduction-en-masse: ‘The
sac together with its contents is pushed forcibly back into the abdomen; as the
bowel will still be strangulated by the neck of the sac, the symptoms are in no
way relieved’ (Treves);
• reduction into a loculus of the sac;
• the sac may rupture at its neck and the contents are reduced, not
into the peritoneal cavity but extraperitoneally.
Results
of operations for inguinal hernia — recurrence. Reported recurrence rates vary
between 0.2 and 15 per cent depending on the technique employed. Only by using a
meticulous technique, principally concentrating on reinforcement of the
posterior wall of the inguinal canal, with the Shouldice technique or mesh
hernioplasty, can a recurrence rate of less than 2 per cent be achieved. Only 50
per cent of recurrences will become apparent within 2 years. In a few cases
‘false’ recurrences occur, i.e. another type of hernia occurs — direct
after indirect, femoral after inguinal. To the patient it is a recurrence!
The
spermatic cord as a barrier to effective closure of the inguinal canal. Even in
the elderly patient, removal of the testis and cord is very rarely required for
effective repair even in cases of recurrent inguinal hernia. In operations for
multiple recurrences or when previous surgery has been associated with
infections or excessive scarring, the operation should be approached through
virgin territory, i.e. the preperitoneal route, by an experienced surgeon.
Sliding
hernia (syn. hernia-en-glissade)
As a result of slipping of the posterior parietal peritoneum on the
underlying retroperitoneal structures, the posterior wall of the sac is not
formed of peritoneum alone, but by the sigmoid colon and its mesentery on the
left, the caecum on the right and, sometimes, on either side by a portion of the
bladder. It should be clearly understood that the caecum, appendix or a portion
of the colon wholly within a hernial sac does not constitute a sliding
hernia. A small bowel sliding hernia occurs approximately once in 2000 cases; a
sacless hernia once in 8000 cases.
Clinical
features
A sliding hernia occurs almost exclusively in males. Five out
A sliding hernia is impossible to control with a truss, and as a rule
the hernia is a cause of considerable discomfort. Consequently, operation is
indicated and the results are very good.
Operation. It is unnecessary to remove any of the sliding hernial sac
provided that it is freed completely from the cord and the abdominal wall, and
that it is replaced deep to the repaired fascia transversalis. In many
circumstances it is desirable to perform orchidectomy in order to effect a
secure repair. No attempt should be made to dissect the caecum or colon free
from the peritoneum under the impression that these are adhesions, in which case
peritonitis or a faecal flstula resulting from necrosis of a devascularised
portion of the bowel may occur. This is especially liable to occur on the left
side, as vessels in the mesocolon may be injured.
Femoral
hernia
Femoral hernia is the third most common type of primary hernia. It
accounts for about 20 per cent of hernias in women and 5 per cent in men.
The overriding importance of femoral hernia lies in the facts that it cannot be
controlled by a truss and that of all hernias it is the most liable to become
strangulated, mainly because of the narrowness of the neck of the sac and the
rigidity of the femoral ring. Strangulation is the initial presentation of 40
per cent of femoral hernias.
Surgical anatomy. The femoral canal occupies the most medial compartment
of the femoral sheath and it extends from the femoral ring
above to the saphenous opening below. It is 1.25 cm long and 1.25 cm
wide at its base, which is directed upwards. The femoral canal contains fat,
lymphatic vessels and the lymph node of Cloquet. It is closed above by the
septum crurale, a condensation of extraperitoneal tissue pierced by lymphatic
vessels, and below by the cribriform fascia.
The
femoral ring is bounded:
• anteriorly by the inguinal
ligament;
• posteriorly by Astley
Cooper’s (ileopectineal) ligament, the pubic bone and the fascia over the
pectineus muscle;
• medially by the concave
knife-like edge of Gimbernat’s (lacunar) ligament, which is also prolonged
along the iliopectineal line as for Astley Cooper’s ligament;
• laterally by a thin septum
separating it from the femoral vein.
Sex
incidence. The female to male ratio is about 2:1, but it is interesting that
whereas the female patients are frequently elderly, the male patients are
usually between 30 and 40 years of age. The condition is more prevalent in women
who have borne children than in nulliparae.
Pathology.
A hernia passing down the femoral canal descends vertically as far as the
saphenous opening. While it is confined to the inelastic walls of the femoral
canal the hernia is necessarily narrow but, once it escapes through the
saphenous opening into the loose areolar tissue of the groin, it expands,
sometimes considerably. A fully distended femoral hernia assumes the shape of a
retort and its bulbous extremity may be above the inguinal ligament. By the time
the contents have pursued so tortuous a path they are usually irreducible and
apt to strangulate.
Clinical
features. Femoral hernia is rare before puberty. Between 20 and 40 years of age
the prevalence rises and continues to old age. The right side (Fig.
62.13) is
affected twice as often as the left, and in 20 per cent of cases the condition
is bilateral. The symptoms to which a femoral hernia gives rise are less
pronounced than those of an inguinal hernia; indeed, a small femoral hernia may
be unnoticed by the patient or disregarded for years, perhaps until the day it
strangulates. Adherence of the greater omentum sometimes causes a dragging pain.
Rarely, a large sac is present.
Differential
diagnosis. A femoral hernia has to be distinguished from the following.
An
inguinal hernia. The neck of the sac lies above and medial to the medial end of the
inguinal ligament at its attachment to the pubic tubercle. The neck of the sac
of a femoral hernia lies below this (Fig. 62.14). The fundus of an inguinal or a
femoral hernia may follow the line of least resistance and occupy a variety of
places, for instance, occasionally the fundus of a femoral hernia sac overlies
the inguinal ligament.
A
saphena varix. A saccular
enlargement of the termination of the long saphenous vein, usually accompanied
by other signs of varicose veins. The swelling disappears completely when the
patient lies flat, while a femoral hernia sac is usually still palpable. In
both, there is an impulse on coughing. A saphena varix will, however, impart a
fluid thrill to the examining fingers when the patient coughs or when the
saphenous vein below the varix is tapped with the fingers of the other hand.
Sometimes a venous hum can be heard when a stethoscope is applied over a saphena
varix.
An
enlarged femoral lymph node. There may
be other enlarged lymph nodes to aid the diagnosis. If Cloquet’s lymph node
alone is affected, it may be impossible to distinguish from a femoral hernia sac
unless there are other clues, such as an infected wound or abrasion on the
corresponding limb or on the perineum.
Lipoma.
A
femoral aneurysm. See Chapter 15.
A
psoas abscess. There is often a fluctuating swelling — an iliac abscess
— which communicates with the swelling in question. If suspected, an
examination of the spine and an X-ray will confirm the diagnosis.
A
distended psoas bursa. The
swelling diminishes when the hip is flexed and osteoarthritis of the hip is
present.
Rupture
of the adductor longus. Rupture of
the adductor longus with haematoma formation — suspected on clinical history.
Hydrocele
of a femoral hernial sac. The neck of the sac becomes plugged with omentum or by
adhesions, and a hydrocele of the sac results.
Laugier’s
femoral hernia. This is a hernia through a gap in the lacunar (Gimbernat’s)
ligament. The diagnosis is based on unusual medial position of a small femoral
hernia sac. The hernia has nearly always strangulated.
Narath’s
femoral hernia. This occurs only in patients with congenital dislocation of the
hip and is due to lateral displacement of the psoas muscle. The hernia lies
hidden behind the femoral vessels.
Cloquet’s
hernia. Cloquet’s hernia is one in which the sac lies under the fascia
covering the pectineus muscle. Strangulation is likely. The sac may coexist with
the usual type of femoral hernia sac.
Strangulated
femoral hernia
A femoral hernia strangulates frequently and gangrene rapidly develops.
This is explained by the narrow, unyielding femoral ring. In 40 per cent of
cases the obstructing agent is not the lacunar ligament but the neck of the femoral sac itself. A
Richter’s hernia is a frequent occurrence (see above).
Treatment
of a femoral hernia. The constant risk of strangulation is sufficient reason
to recommend operation, which should be carried out soon after the diagnosis has
been made. A truss is contraindicated because of this risk.
Operative treatment. Several approaches to the femoral hernia have been advocated including the low operation (Lockwood), the high operation (McEvedy) and the inguinal operation (Lotheissen). In all cases the bladder must be emptied by catheterisation immediately before commencing surgery.
(The low operation (Lockwood). The sac is dissected out below the
inguinal ligament via a groin-crease incision. It is essential to peel off the
anatomical layers which cover the sac. These are often thick and fatty. After
dealing with the contents (e.g. freeing adherent omentum) the neck of the sac is
pulled down, ligated as high as possible and allowed to retract through the
femoral canal. The canal may be closed by suturing the inguinal ligament to the
iliopectineal line using three nonabsorbable sutures. An alternative method of
closure is to roll a sheet of polypropylene mesh into a cylinder and anchor
the cylinder in the canal with nonabsorbable sutures placed medially, superiorly
and inferiorly.
The
high (McEvedy) operation. Classically, a vertical incision is made over the
femoral canal and continued upwards above the inguinal ligament. An acceptable
alternative that heals well and with less pain is to use a ‘unilateral’
Pfannenstiel incision, which can be extended to form a complete Pfannenstiel
incision if formal Laparotomy is required. This incision provides good access to
the preperitoneal space. Through the lower part of the incision the sac is
dissected Out. The upper part of the incision exposes the inguinal ligament and
the rectus sheath. The superficial inguinal ring is identified and an incision 2.5
cm above the ring and parallel to the outer border of the rectus muscle is
deepened until the extraperitoneal space is identified. By gauze dissection in
this space the hernial sac entering the femoral canal can be easily identified.
Should the sac be empty and small, it may be drawn upwards; if it is large, the
fundus is opened below and its contents, if any, dealt with appropriately before
delivering the sac upwards from its canal. The sac is then freed from the
extraperitoneal tissue and its neck ligated. An excellent view of the iliopectineal
ligament is obtained and the conjoined tendon is sutured to it with
nonabsorbable sutures. An alternative repair, particularly suitable for
recurrent femoral hernias, is to suture a sheet of polypropylene mesh over the
femoral canal orifice, anchoring the mesh inferiorly to the iliopectineal
ligament and medially to the rectus sheath.
An
advantage of this approach is that if resection of intestine is required, ample
room can be obtained by opening the peritoneum. The disadvantage of this
approach is that if infection occurs, an incisional hernia may develop.
Lotheissen’s
operation. The inguinal canal is opened as for inguinal herniorrhaphy. The
transversalis fascia is incised to the medial side of the epigastric vessels and
the opening is enlarged. The peritoneum is now in view; one must be certain that
it is the peritoneum and not the bladder or a diverticulum thereof. The
peritoneum is picked up with dissecting forceps and incised. It is now possible to ascertain whether any
intraperitoneal structure is entering the femoral sac. Should the sac be empty,
haemostats are placed upon the edges of the opening into the peritoneum and, by
gauze dissection, the sac is withdrawn from the femoral canal. An empty sac can
be delivered easily. If strangulation is suspected, as soon as the external
oblique has been exposed, the inferior margin of the wound is retracted, thereby
displaying the swelling. The coverings of the sac are incised and peeled off,
until the sac, dark from contained blood stained fluid, is apparent. The sac is
incised and the fluid that escapes is mopped up with care. The retractor is
removed and the operation is continued above the inguinal ligament as described
above. Once the peritoneum has been opened above the inguinal ligament, one can
see exactly what is entering the sac. Should the obstruction lie in a narrow
neck of the sac, the neck of the sac may be gently stretched by insertion of a
haemostat. (An abnormal obturator artery is present either on the medial or the
lateral side of the neck of the sac in 28 per cent of cases.) The contents of
the sac are delivered and dealt with appropriately. Sometimes, in order to
facilitate reduction of the hernial contents, it becomes necessary to divide or
digitally dilate part of the lacunar (Gimbernat’s) ligament.
The
Lotheissen repair is effected by suturing the conjoined tendon to the
iliopectineal line to form a shutter. While protecting the external
iliac/femoral vein with the forefinger, nonabsorbable sutures are passed through
the periosteum and Cooper’s ligament overlying the iliopectineal line. The
retractor is removed and the long ends of the sutures are passed from within,
outwards, through the conjoined tendon and tied, thus approximating the
conjoined tendon to the iliopectineal line. If there is any tension, a
Tanner’s slide will facilitate this step. The incised external oblique is
sutured.
An
alternative repair is to buttress the femoral canal with a sheet of
polypropylene mesh. Once the sac has been dealt with, a sheet of mesh is
inserted into the preperitoneal space and anchored inferiorly to the iliopectineal
line, inferomedially to Cooper’s ligament and superomedially
to the rectus sheath. The transversalis fascia may then be approximated in front
of the mesh and the incised external oblique repaired. It should be noted that
the peritoneum must be closed before placement of the mesh.
NB.
Throughout operations for the repair of a femoral hernia, on the lateral side,
the external iliac/femoral vein must be protected, and on the medial side, great
care must be taken not to injure the bladder, particularly as a portion of the
bladder may form part of the wall of the sac (a sliding femoral hernia).
Umbilical
hernia
Exomphalos
(syn. omphalocele) occurs once in
every 6000 births; it is due to failure of all or part of the midgut to return
to the coelom during early foetal life. There is some debate as to whether
gastroschisis represents a separate entity or is simply an exomphalos with
ruptured membranes, but the debate has little practical importance because the
principles of treatment are similar. When the sac remains unruptured, it is
semitranslucent (Fig. 62.15) and, although very thin, it consists of two layers
— an outer layer of amniotic membrane and an inner layer of peritoneum.
Omphaloceles may be divided into those with a fascial defect of less than or
greater than 4 cm. The former are termed herniation of the umbilical cord. In
smaller defects, a single loop of intestine may not be obvious and ligation of
what was thought to be a normal umbilical cord will result in transection of the
intestine, leaving the embarrassing problem of an umbilico-enteric fistula.
In
large defects the liver, spleen, stomach, pancreas, colon or bladder may be seen
through the membrane. The intestine lies freely mobile within the intact sac
without evidence of adhesions or inflammation. In contrast, the liver has dense
adhesions to the sac, a fact which must be remembered during surgical repair.
Treatment
Large defects present a more substantial problem and four techniques have been described: nonoperative therapy, skin flap closure, staged closure, and primary closure
Nonoperative therapy. This is appropriate for premature infants with
a gigantic intact sac or those in whom associated anomalies make
Skin
flap closure. The sac is gently trimmed away enabling inspection of the
abdominal contents. The skin is freed from the fascial edges and undermined
laterally. The umbilical vessels are ligated or one artery is cannulated for
monitoring. The skin flaps are approximated in the midline with simple sutures
and the ventral hernia is then closed at a later date (months to years later).
Staged
closure. The sac is gently trimmed away from the skin edge and the skin further
freed from the fascial attachments. The prosthetic material [polypropylene mesh
or expanded polytetrafluoroethylene (PTFE)] is sutured with interrupted
nonabsorbable sutures circumferentially to the full thickness of the
musculofascial abdominal wall to form a silo. The top of the silo is gathered
and tied with umbilical tape. At daily intervals, the silo is opened under
strict aseptic conditions and the contents are examined for infection or
dehiscence. The viscera are pushed gently back in to the abdominal cavity and
the infant is observed for signs of raised intra-abdominal pressure. The silo is
then tied at a reduced level and the cycle repeated until the sac is flush with
the abdominal wall. At this stage, the fascia may be closed with interrupted
sutures and skin closed over the top.
Primary
closure. The sac is gently dissected away from the skin edge and the underlying
fascia. The intestine is then evacuated completely of meconium and fluid
distally and proximally through a nasogastric tube. The abdominal wall is
stretched gradually and repeatedly in quadrants, usually achieving a doubling of
volume. The viscera are then replaced and
the fascial layer is closed primarily, usually under moderate tension.
Intragastric pressure monitoring is helpful to prevent undue vena caval
compression.
Congenital
umbilical hernia. Rarely, a fully developed umbilical herniais present at birth,
presumably due to intrauterine epithelialisation of a small exomphalos.
Umbilical
hernia of infants and children
This is a hernia through a weak umbilicus which may partially result
from failure of the round ligament (obliterated umbilical vein) to cross the
umbilical ring and partially from absence of the Richet fascia. Both sexes seem
to be equally affected, although there are significant racial differences, with
the incidence in black infants reported as up to eight times higher than in
white infants. The hernia is often symptomless but increases in size on crying
and assumes a classical conical shape (Fig. 62.16). Obstruction or strangulation
below the age of 3 years is extremely uncommon.
Treatment.
Conservative treatment is indicated under the age of 2 years. When the hernia is
symptomless, reassurance of the parents is all that is necessary and 95 per
cent of hernias will disappear spontaneously. If the hernia persists at 2 years
of age or older, it is unlikely to resolve and herniorrhaphy is indicated.
Paraumbilical
hernia (syn. supraumbilical or
infraumbilical
hernia)
In adults the hernia does not occur through the umbilical scar. It is a
protrusion through the linea alba just above or sometimes just below the
umbilicus (Fig. 62.17). As it enlarges it
Clinical
features. Women are affected five times more frequently than men. The patient is
usually overweight, and between the ages of 35 and 50 years.
Increasing obesity, with flabbiness of the abdominal muscles, and repeated
pregnancy are important aetiological factors. These hernias may become
irreducible owing to the formation of omental adhesions within the sac.
Symptomatically, a large umbilical hernia causes a dragging pain by its weight.
Gastrointestinal symptoms are common and are probably due to traction on the
stomach or transverse colon. Often there are transient attacks of intestinal
colic due to partial intestinal obstruction. In longstanding cases Intertrigo of the adjacent surfaces of skin and trophic ulcers of the fundus are
troublesome complications.
Treatment.
Untreated, the hernia increases in size and more and more of its contents become
irreducible. Eventually, strangulation may occur. Therefore operation should be
advised in nearly all cases. If the patient is obese and the hernia is
symptomless, operation can be postponed until the patient has lost weight.
Epigastric
herniorrhaphy. If the defect is small, a primary herniorrhaphy can be performed.
If the defect is large, the repair is best performed with prosthetic buttressing
of the abdominal wall. The classic primary repair is that described by Mayo. A
transverse elliptical incision is made around the umbilicus and the subcutaneous
tissues are dissected off the rectus sheath to expose the neck of the sac. The
neck is incised to expose the contents. Intestine is returned to the abdomen and
any adherent omentum freed. Excess adherent omentum can be removed with the sac if necessary. The sac is then removed and the peritoneum
closed with an absorbable suture. The aponeurosis on both sides of the umbilical
ring is mobilised from underlying tissue sufficiently to allow an overlap of 5
or 7.5 cm. Interrupted mattress sutures are then inserted into the
aponeurosis, as shown in Fig. 62.18. When this row of mattress sutures has been
tied, the overlapping upper margin is stitched to the sheath of the rectus
abdominis and the midline aponeurosis. A suction drain should be placed in the
wound in fat patients, who ooze blood and liquid fat. The subcutaneous fat and
skin are then approximated with deep sutures.
Paraumbilical
hernioplasty. In the case of very large primary paraumbilical hernias (fascial
defect > 4 cm) or for recurrent paraumbilical hernias, the use of prosthetic
material (polypropylene mesh) is recommended.
Additional
lipectomy. In patients with a paraumbilical hernia associated with a large,
pendulous, fat-laden abdominal wall the operation can, with great advantage, be
combined with panniculectomy by fashioning the incisions to embrace a larger
area of the fat-laden superficial layers of the abdominal wall.
Strangulation
is a frequent complication of a large
paraumbilical hernia in adults. Owing to the narrow neck and the fibrous edge of
the linea alba, gangrene is liable to supervene unless early operation is
carried out. It should also be remembered that in large hernias the presence of
loculi may result in a strangulated knuckle of the bowel in one part of an
otherwise soft and nontender hernia.
Operation.
In early cases, the operation does not differ from that for nonstrangulated
cases. Gangrenous contents are dealt with as in other situations. If a portion
of the transverse colon is gangrenous, it should be exteriorised by the Paul—Mikulicz
method and the gangrenous portion excised. If the ring is large enough to
transmit the colon unhampered, it is left alone; otherwise it is enlarged. It is
important that the small intestine be thoroughly scrutinised as a small loop may
have been trapped and slipped back when the constriction was relieved. If
nonviable gut is overlooked, peritonitis quickly supervenes and the symptoms are
ascribed to postoperative discomfort. The condition of the patient steadily
deteriorates until they succumb after a few days.
Epigastric
hernia (syn. fatty hernia of the linea alba)
An epigastric hernia occurs through the linea alba anywhere between the
xiphoid process and the umbilicus, usually midway between these structures. Such a hernia commences as a
protrusion of extraperitoneal fat through the linea alba, and it was
hypothesised that this protrusion occurs at the site where small blood vessels
pierced the linea alba. However, only a minority of epigastric hernias is
accompanied by blood vessels, and it is more likely that the defect occurs as a
result of a weakened linea alba due to abnormal decussation of the fibres of the
aponeurosis. More than one hernia may be present and the commonest cause of
‘recurrence’ is failure to identify a second defect at the time of original
repair.
A
swelling the size of a pea consists of a protrusion of extraperitoneal fat only
(fatty hernia of the linea alba). If the protrusion enlarges, it drags a pouch
of peritoneum after it and so becomes a true epigastric hernia. The mouth of the
hernia is rarely large enough to permit a portion of hollow viscus to enter it;
consequently, either the sac is empty or it contains a small portion of greater
omentum.
It
is probable that an epigastric hernia is the direct result of
a sudden strain tearing the interlacing fibres of the linea alba.
The patients are often manual workers between 30 and
Clinical
features
• Symptomless —
a small fatty hernia of the linea alba can be felt better than it can be seen
and may be symptomless, being discovered only in the course of routine abdominal
palpation.
• Painful — sometimes
such a hernia gives rise to attacks of local pain, worse on physical exertion,
and tenderness to touch and light clothing. This may be because the fatty
contents become nipped sufficiently to produce partial strangulation.
• Referred pain — it is not uncommon to find that the patient, who may not have noticed the hernia, complains of pain suggestive of a peptic ulcer. However, as the majority of these hernias is asymptomatic, symptoms should not be ascribed to the hernia until any gastrointestinal pathology has been excluded.
Treatment
If the hernia is giving rise to symptoms, operation should be
undertaken.
Rare
external hernias
Interparietal
hernia (syn. interstitial hernia). An
interparietal hernia has a hernial sac which passes between the layers of the
anterior abdominal wall. The sac may be associated with, or communicate with,
the sac of a concomitant inguinal or femoral hernia. Lack of knowledge of this
condition is the cause of misdiagnosis and mismanagement.
Other
varieties.
• Preperitoneal (20
per cent) — usually the sac takes the form of a diverticulum from a femoral or
inguinal hernia.
• Intermuscular (60
per cent) — the sac passes between the muscular layers of the anterior
abdominal wall, usually between the external oblique and internal oblique
muscles. The sac is nearly always bilocular and is associated with an inguinal
hernia.
• Inguinosuperficial (20
per cent) — the sac expands beneath the superficial fascia of the abdominal
wall or the thigh. This type is commonly associated with an incompletely
descended testis.
Clinical
features. The patients (mostly
male) present with intestinal obstruction, due to obstruction or strangulation
of the hernia. In the preperitoneal variety, as no swelling is likely to be
apparent, delays in diagnosis occur and consequently the mortality in this
variety is high.
Treatment.
Operation is imperative because of
intestinal obstruction.
Spigelian
hernia. This is a variety of interparietal hernia occurring at the level of the
arcuate line. It is very rare with only 1000 cases reported in the literature.
The fundus of the sac, clothed by extraperitoneal fat, may lie beneath the
internal oblique muscle where it is virtually impalpable. More often it advances
through that muscle and spreads out like a mushroom between the internal and
external oblique muscles, and gives rise to a more evident swelling. The patient
is often corpulent and usually over 50 years of age, men and women being equally
affected. Typically, a soft, reducible mass will be encountered lateral to the
rectus muscle and below the umbilicus. Diagnosis is confirmed by computerised
tomography (CT) or ultrasound scanning, the latter having the advantage of being
able to stand the patient upright if no defect is visible in the reclining
position. Owing to the rigid fascia surrounding the neck, strangulation may
occur.
Treatment.
Operation. If a defect is
palpable, a muscle-splitting approach is used. After isolating the sac, dealing
with any contents, and ligating and excising it, the transversus, internal
oblique and external oblique muscles are repaired by direct apposition. If no
sac is palpable, a paramedian approach is used and the sac sought in the
extraperitoneal space. The repair then proceeds as described above.
Lumbar
hernia. Most primary lumbar hernias occur through the inferior lumbar triangle
of Petit (Fig. 62.19), bounded below by the crest of the ilium, laterally by the
external oblique and medially by the latissimus dorsi. Less commonly, the sac
comes through the superior lumbar triangle which is bounded by the twelfth rib
above, medially by the sacrospinalis and laterally by the posterior border of
the internal oblique. Primary lumbar hernias are very rare with only 300 cases
reported. More commonly lumbar hernias are secondary to renal operations, when
extensive incisional sacs may be present.
Differential diagnosis. A lumbar hernia must be distinguished from
• lipoma;
• a cold abscess pointing to this position;
• phantom hernia due to local muscular paralysis. Lumbar phantom hernia
can result from any interference with the nerve supply of the affected muscles
(e.g. poliomyelitis).
Treatment.
A primary lumbar hernia, being
small, is easily repaired. As the natural history is for these hernias to
increase in size with time, any primary lumbar hernia should be repaired at
presentation. Incisional lumbar hernias may be large and the defect is
impossible to repair unless fascial flaps are used. The repair can be reinforced with a
sheet of polypropylene mesh.
Perineal
hernia. This type of hernia is very rare. Varieties include:
• postoperative hernia through a
perineal scar may occur after excision
of the rectum;
• median sliding perineal hernia is a complete prolapse of the rectum (Chapter 60);
• anterolateral perineal hernia occurs
in women and presents as a swelling of the labum majus;
• posterolateral perineal hernia, which
passes through the levator ani to enter the ischiorectal fossa.
Treatment.
A combined operation is generally
the most satisfactory for the last two types of hernia. The hernia is exposed by
an incision directly over it. The sac is opened and its contents are reduced.
The sac is cleared from surrounding structures and the wound closed. With the
patients in semi-Trendelenburg position, the abdomen is opened and the mouth of
the sac is exposed. The sac is inverted, ligated and excised and the pelvic
floor repaired by muscle apposition and, if indicated, buttressing of the repair
with prosthetic mesh.
Obturator
hernia. The hernia, which passes through the obturator canal, occurs six times
more frequently in women than in men. Most of the patients are over 60 years of
age. The swelling is liable to be overlooked because it is covered by the
pectineus. It seldom causes a definite swelling in Scarpa’s triangle, but if
the limb is flexed, abducted and rotated outwards, sometimes the hernia becomes
more apparent. The leg is usually kept in a semiflexed position and movement
increases the pain. In more than 50 per cent of cases of strangulated obturator
hernia, pain is referred along the obturator nerve by its geniculate branch to
the knee. On vaginal or rectal examination the hernia sometimes can be felt as a
tender swelling in the region of the obturator foramen.
Cases
of obturator hernia which present themselves have usually undergone
strangulation, which is frequently of the Richter type.
Treatment.
Treatment consists of the
following:
• perform lower laparotomy (on the side of the lesion, if known).
Confirm the diagnosis and then adopt full Trendelenburg’s position;
•
the constricting agent is the obturator fascia. Taking every precaution
to avoid spilling infected fluid from the hernial sac into the peritoneal
cavity, this fascia can be stretched to allow reduction by inserting suitable
forceps through the gap in the fascia and opening the blades with care. If
incision of the fascia is required, it should be made parallel to the obturator
vessels and nerve;
•
the contents of the sac are dealt with;
•
the broad ligament is stitched over the opening to prevent recurrence.
Gluteal
and sciatic hernias. A gluteal hernia passes
through the greater sciatic foramen, either above or below the piriformis. A sciatic
hernia passes through the lesser sciatic foramen. Differential diagnosis
must be made between these conditions and:
•
a lipoma or fibrosarcoma beneath the gluteus maximus;
•
a tuberculous abscess;
•
a gluteal aneurysm.
All doubtful swellings in this situation
should be explored by operation.