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Functional anatomy of the groin area as related to the classification and treatment of groin hernias
Functional
Anatomy
Related
of the Groin
Area
to the Classification
Treatment
of Groin
as
and
Hernias
DANIEL F. CASTEN, M.D., NOW York, New York
From the Departments of Surgery, Sydenham St. Clare’s Hospital, and Hospital for Joint New York, New York.
The transversalis is a broad sheet of endoabdominal fascia investing the peritoneal cavity. Superiorly, it protects the esophageal hiatus as the phrenoesophageal ligament. Inferiorly, it is reflected from the iliopsoas fascia, is attached firmly to Cooper’s ligament (but not to the inguinal ligament), and forms the floor of the inguinal canal. The internal ring is an aperture in the transversalis fascia and this fascia lends a covering to the cord structures as they pass through the internal ring on descent to the scrotum. There are two condensations of transversalis fascia in the inguinal area: Thomson’s ligament or the iliopubic tract which is the firm lateral border of the internal ring extending to Cooper’s ligament, and Hesselbach’s ligament which strengthens the medial margin of the internal ring. Of these, the iliopubic tract is invariably found in the inguinal canal at operation but Hesselbach’s ligament is somewhat more tenuous and, in fact, may be completely absent as the medial border of the internal ring. The transversalis fascia is the key structure in hernia repair since it provides the essential protection for the floor of the inguinal canal and the internal ring. The aponeurosis of the transversus abdominis reinforces the floor of the inguinal canal and may be fused with the transversalis fascia in this area. It inserts laterally by way of the lacunar ligament into Cooper’s ligament and medially into the rectus sheath. Rarely, it fuses with the aponeurosis of the internal oblique to form the conjoined tendon. However, in over 90 per cent of the specimens investigated a true conjoined tendon was absent and
Hospital, Diseases,
HE INGUINAL CANAL in its fUnCtiOn aS a conduit for the passage of the cord structures is the weakest portion of the abdominal wall. Either through congenital defect or by work atrophy, weakness in this area results in herniation of abdominal contents. This weakness is the result of functional dystrophy, and logical therapy is based on awareness of the functional structures which compose the groin area. The purpose of this report is to present a concept of the functional anatomy of the inguinal area in relation to the develqpment and treatment of groin hernias. A classification of groin hernias is proposed and appropriate surgical treatment for the repair of each type of hernia is described. The present data are reported on the basis of the operative findings and results in the repair of 854 groin hernias and upon numerous cadaver dissections.
T protective
FUNCTIONAL ANATOMY OF THE GROIN AREA The three principal functional structures in the inguinal area are the transversalis fascia, the transversus abdominis aponeurosis, and the iliopectineal or Cooper’s ligament. Other structures commonly employed in the repair of groin hernias, the internal oblique muscle and aponeurosis, the cremaster muscle, and the inguinal ligament, are not considered in the present context as functional structural units. 894
American
Journal
of
Surgery
Groin Hernias the insertion of transversus abdominis aponeurosis was independent of that of the internal oblique muscle. Transversus abdominis aponeurosis, when fused with transversalis fascia, forms a strong fascial layer which reinforces the floor of the inguinal canal. Therefore, in repair of inguinal hernias the transversus abdominis aponeurosis may be sutured to Cooper’s ligament but not to inguinal ligament since it has no normal attachments to inguinal ligament. Henle’s ligament arises from the aponeurotic insertion of transversus abdominis and strengthens the medial portion of the inguinal canal. However, this structure, too, may be tenuous and in many specimens is completely absent. The pectineal or Cooper’s ligament is a broad, thick, and strong fascial structure covering the superior pubic ramus from the pubic tubercle to the femoral vessels. To it is attached the iliopubic tract and transversus abdominis. The internal oblique is not inserted into Cooper’s ligament. This ligament is the posterior boundary of the femoral canal. Cooper’s ligament represents the site of fascial aponeurotic attachment and should be used in the repair of groin hernias in cases in which the floor of the inguinal canal has been destroyed by attenuation or work atrophy. There are several minor structures in the inguinal canal commonly used in the repair of groin hernia but which, according to the present concept, are not basic structural units and are not functional in the repair of these hernias. Of these, the internal oblique muscle is first considered. This arises from the lumbodorsal and iliopsoas fascia with the cremaster muscle and arches over and protects the internal ring, inserting into the rectus sheath as an aponeurotic sheet. Rarely it forms a conjoined tendon with the transversus abdominis. It overlies the internal ring and, in contracting, it protects this ring by sphincteric action. Fixation of this muscle by suture destroys this muscular sphincter and therefore has no place in the repair of inguinal hernias. The external oblique aponeurosis is the aponeurotic insertion of the external oblique and forms the roof and lateral boundary of the inguinal canal as well as the anterior border of the femoral ring. Split fibers of its insertion form the external ring. Neither the internal oblique nor the transversus abdominis muscle is attached to this ligament and should not be Vol. 114, December
1967
895
sutured to it in inguinal hernia repair. The external oblique aponeurosis is functionally indifferent and presents no barrier to the formation or progress of inguinal hernias since complete excision of this structure, as in radical groin dissection, does not result in hernia if the transversus abdominis and transversalis fascia are sutured to Cooper’s ligament. The present concept emphasizes the absence of structural or functional capacity of the external oblique aponeurosis and therefore eliminates this structure as a structural unit in hernia repair. The conjoined tendon is largely an ephemeral structure which is occasionally formed by fusion of the aponeurosis of the internal oblique and transversus abdominis as they insert into the pubic tubercle. When present (in approximately 10 per cent of the patients), it is rarely more than a few centimeters long and has no clinical significance in the repair of groin hernias. Internal oblique aponeurosis may reach the pubic tubercle but inserts primarily into the rectus sheath. The insertion of the transversus abdominis and Henle’s ligament may be mistakenly called the conjoined tendon. The cremaster muscle arises from the internal oblique at the iliopsoas fascia and separates from this muscle to form a covering for the cord structures. It is in no way functional and serves no purpose in the repair of inguinal hernias. It may be excised completely to present a clearer definition of the internal ring for purposes of closure of this structure during the repair of indirect inguinal hernia. The treatment of the hernial sac requires some elaboration. There is considerable variation in the pathogenesis of the indirect and the direct sac. The indirect sac is a congenital anomaly due to persistence of the processus vaginalis. As this structure enlarges, it weakens the internal ring. It presents as a structural defect and should be radically excised in the repair of indirect hernias. On the other hand, the direct sac is the result and not the cause of direct inguinal hernias. It results from weakness and attenuation of the transversalis fascia which forms the floor of the inguinal canal at Hesselbach’s triangle. The sac then presents as a secondary manifestation of this weakness. During the repair of direct hernias the sac must be completely liberated and reduced but need not be opened. It is our present
Casten
896
IOHYPOGASTRIC N.
TRANS. FASCIA
2
1 FIG. 1. Stage I hernia repair.
FIG. 2. Stage I hernia repair. Exposure of the inguinal canal. FIG. 3. Stage I hernia repair. Excision of the cremaster muscle and retraction
practice to reduce the direct sac without ‘excision of this structure. CLASSIFICATION
AND TREATMENT
OF
GROIN HERNIAS
On the basis of the preceeding brief anatomic considerations, a classification of groin hernias is presented which forms the basis for the surgical treatment of the various types of hernias presenting in this area. In presenting this classification, stress is placed on correction of the underlying functional deficit resulting in the development of each type of groin hernia. Although no mention has been made of femoral hernias, it is believed that the simple attenuation of transversalis fascia covering the femoral ring is responsible for the development of femoral hernias. Careful exploration of the femoral canal during the repair of inguinal hernias has indicated that in the absence of femoral hernias this ring is protected by a thin layer of transversalis fascia which adequately prevents the protrusion of the abdominal contents through this opening. Stage I hernias are defined as indirect inguinal hernias in patients (usually infants and children) in whom the internal ring is perfectly normal in size, configuration, and structure. The boundaries are well marked and in most instances both Hesselbach and Thomson’s ligaments are well defined. The simple anatomic defect is the presence of an indirect hernial sac. This is usually congenital, but it is possible
of the ilioinguinal nerve.
that in some patients a small unobliterated processus vaginalis may provide the nidus for the subsequent development of a larger indirect hernia without distortion of the internal ring. Treatment is based on correction of the simple anatomic defect, namely, the presence of a sac. In children it is usually not necessary to open the entire inguinal canal. The usual skin incision is made (which may be either transversely or obliquely placed) and the two or three constant vessels in the subcutaneous fat between skin and superficial fascia are exposed. These are the superficial epigastric vessels, the superficial external pudendal vessels, and occasionally superficial circumflex iliac vessels. These are doubly ligated and divided. The external oblique is then exposed and a 3 cm. incision is made through this structure directly over the internal ring. (Fig. 1.) The edges of this incision are retracted and the hernial sac is readily exposed lying anterior and medial to the cord structures. The sac is grasped with a fine forceps and dissected free from the cord structures. The cord structures are not disturbed or lifted from their normal position. As dissection is continued cephalad, the filmy attachments of the sac to the cremaster are divided by sharp dissection. The internal ring is clearly exposed by retraction of the internal oblique muscle cephalad. The sac is dissected down to its intra-abdominal portion. It is .then transfixed with No. 4-O silk suture and the American Journal
of Surgery
Groin Hernias
897
I IT. OBLIQUE Y.
.i 4
5
6
FIG. 4. Stage I hernia repair. High ligation of the sac.
FIG. 5. Stage internal ring.
II
hernia repair. High ligation of the sac, ligation of the external spermatic vessel, and exposure of the
FIG. 6. Stage
II
hernia repair. Closure of the internal ring.
excess sac is removed. The internal ring is inspected and is found to be normal. The cut edges of the external oblique are approximated with two or three sutures of No. 4-O silk. The skin may be closed with a subcuticular suture of fine silk. In older patients and particularly in those with somewhat larger hernias the external oblique is opened to the external ring. The ilioinguinal and iliohypogastric nerves are exposed and preserved. (Fig. 2.) The joined origin of internal oblique muscle and cremaster muscle is readily demonstrated. The cremaster may be excised if necessary. (Fig. 3.) The sac is then mobilized and dissected free from the cord structures. At the internal ring it is freed completely from its attachments. At this point it may be opened and inspected or may be twisted and transfixed with a No. 4-O silk suture high at the intra-abdominal portion. High ligation of the sac above the internal ring is mandatory. (Fig. 4.) The excess portion of the sac is removed. The internal ring is now inspected and in these patients it is found to be normal. The external oblique is approximated over the cord structures with interrupted sutures of No. 3-O silk. Skin closure is in the usual fashion. In the present series eighty-six operations were performed for stage I hernias. In no patient was the internal ring sutured. There were no recurrences in the group, Vol. 114
December
1967
Stage 1I hernias are defined as indirect inguinal hernias in patients in whom the internal ring is enlarged and distorted. The sac may be congenital or acquired. The edges are not as well formed as in stage I hernias but may be clearly observed. Commonly, a firm iliopubic tract can be demonstrated but Hesselbach’s ligament may be indistinct or absent. Sliding hernias of sigmoid or cecum are usually classified as stage II hernias since these are commonly indirect inguinal hernias. Although the treatment of the sac may be modified in the treatment of sliding hernias of the indirect variety, the basic principles of repair are unvarying. The technic of repair in stage II hernias is based on the recognition of the disability related to the enlarged and distorted internal ring. As an aid in exposure, the cremaster muscle is frequently excised. The cord structures are lifted and retracted and the sac is readily exposed in its medial and anterior portion. The external spermatic vessels arising from the inferior epigastric vessles are exposed and divided between suture ligatures of No. 4-O silk. After excision of the cremaster muscle the sac is readily dissected to its exit from the internal ring. At this point the sac is opened and the contents are reduced. High ligation of the sac is accomplished as in the preceding technic. A transfixion suture of No. 3-O silk or interrupted sutures of No. 3-O or
Casten
898
INTERNAL RING
~RANS.FASW 7 FIG. 7. Stage III hernia repair. Mobilization
COOPER'S LIG. 8 of the sac.
FIG. 8. Stage III hernia repair. Suture of the medial aponeurotic FIG. 9. Sage
III hernia repair. Transitional
COOPER'S LIG. 9 structure of Cooper’s ligament.
suture and repair of the internal ring.
4-O may be used for closure of the sac. (Fig. 5.) The internal ring is now exposed by retraction of the cord structures. The sac has retracted within the abdominal cavity. The internal oblique muscle may be retracted medially and cephalad for better exposure of the internal ring. The edges of the ring are now approximated with interrupted sutures of No. 3-O or 4-O silk. (Fig. 6.) The aponeurosis of the internal oblique and the shelving edge of the inguinal ligament are never utilized in this repair. The insertion of transversalis fascia as Thomson’s ligament into Cooper’s ligament can be readily demonstrated at this stage of the exposure. From three to six sutures are placed in the edges of the internal ring leaving the resulting aperture adequate for the exit of the cord structures. The veins of the spermatic cord are not excised. The cord is then dropped back into its normal position and the external oblique approximated over the cord structures with interrupted sutures of No. 3-O silk. The skin is closed in the usual fashion. Four hundred eighty-four operations of this type were carried out in this series for stage II hernias. There were four recurrences or 0.8 per cent in this group of patients. Reoperation on these patients disclosed that in three patients a direct sac had been overlooked and in one patient there was a recurrence as an indirect hernia. Stage III hernias are defined as all direct and femoral hernias. The inclusion of femoral
hernias in this stage is related to the fact that the proposed repair for femoral hernias is identical to that of all stage III or direct hernias. These hernias are always acquired and represent work atrophy or attenuation of the transveralis fascia which normally protects the floor of the inguinal canal in the area of Hesselbach’s triangle. Operative repair of stage III hernias is performed through the usual exposure of the inguinal canal. Careful inspection of the internal ring is made to exclude the presence of a coexistent indirect hernia. If none is found, the cord structures are mobilized and retracted laterally. The large bulge in Hesselbach’s area now delineates the presence of a direct hernia. A circumferential incision is made through the attenuated transversalis fascia which covers the sac. (Fig. 7.) This attenuated transversalis fascia which has been circumscribed is now removed exposing the preperitoneal fat covering the hernial sac. After removal of this circumscribed fascia the sac is readily reduced within the abdominal cavity. Careful inspection now reveals a sharp medial edge of transversalis fascia bounding the defect. Occasionally the aponeurosis of the transversus abdominis is fused with transversalis fascia. Tracing this edge medially and inferiorly leads to the lacunar ligament which can now be readily demonstrated as the insertion of transversus abdominis aponeurosis into Cooper’s ligament. Cooper’s ligament is readily exposed by retracting the reduced sac medially and cephalad. The femoral American
Journal
of Swgery
Groin vessels are now clearly seen at the lateral margin of Cooper’s ligament. Repair is effected by suturing transversalis fascia or fused transversalis and transversus abdominis aponeurosis to Cooper’s ligament. (Fig. 8.) The first suture is placed through the lacunar ligament to close securely the lower innermost portion of the canal. Sutures are then placed serially between the fused medial structures and Cooper’s ligament until the area of the retracted femoral vessels is reached. Approximately four to seven sutures are usually required; No. 2-O silk is used for these sutures. At this point it is necessary to reduce the size of the internal ring. The medial edge of transversalis fascia at the internal ring which has been previously demonstrated is now sutured to the iliopubic tract. The first suture is placed between transversalis fascia, Cooper’s ligament, and the iliopubic tract or femoral sheath. This is called the transitional suture and closes effectively the area between the two diverging lines of sutures. (Fig. 9.) Sutures are then placed serially between the transversalis fascia and iliopubic tract until the internal ring is sufficiently narrowed. The importance of the transitional suture between transversalis fascia, Cooper’s ligament, and the iliopubic tract cannot be overstressed. It should be noted that in no patient in this series has it been necessary to incise transversus abdominis aponeurosis to effect a firm closure of the floor of the canal. It is believed that since transversalis fascia in this area is quite mobile, incision in the fused aponeurosis of insertion of internal oblique and transversus abdominis
Vol. 114. Decembev 1967
Hernias
899
in no way releases transversalis fascia, nor is it necessary to release it. In those patients in whom transversus abdominis at its insertion is fused with transversalis fascia it has been the author’s experience that a snug repair can invariably be accomplished without the necessity of a relaxing incision. Two hundred eighty-five operations have been performed for stage III hernias. There were four recurrences or 1.4 per cent in this group of patients. Femoral hernias are repaired in a fashion identical to that described herein for direct inguinal hernias. Since the fusion of transversalis fascia and transversus aponeurosis to Cooper’s ligament by suture repair completely protects the femoral ring of which Cooper’s ligament is the posterior boundary, this repair is quite effective in curing femoral hernias. The sac is treated in a fashion similar to that described for direct hernia. CONCLUSION
Based on the analysis of the functional anatomy of the inguinal canal, a classification of groin hernias is proposed which forms the basis for treatment. The functional anatomy is described and the appropriate treatment described and depicted. It is believed that a higher cure rate may be anticipated by the exclusive use of functional structures in the repair of groin hernias and it has been found that these structures are readily available, may be sutured without tension and result in a high percentage of cures.
Anatomy
Related
of the Groin
Area
to the Classification
Treatment
of Groin
as
and
Hernias
DANIEL F. CASTEN, M.D., NOW York, New York
From the Departments of Surgery, Sydenham St. Clare’s Hospital, and Hospital for Joint New York, New York.
The transversalis is a broad sheet of endoabdominal fascia investing the peritoneal cavity. Superiorly, it protects the esophageal hiatus as the phrenoesophageal ligament. Inferiorly, it is reflected from the iliopsoas fascia, is attached firmly to Cooper’s ligament (but not to the inguinal ligament), and forms the floor of the inguinal canal. The internal ring is an aperture in the transversalis fascia and this fascia lends a covering to the cord structures as they pass through the internal ring on descent to the scrotum. There are two condensations of transversalis fascia in the inguinal area: Thomson’s ligament or the iliopubic tract which is the firm lateral border of the internal ring extending to Cooper’s ligament, and Hesselbach’s ligament which strengthens the medial margin of the internal ring. Of these, the iliopubic tract is invariably found in the inguinal canal at operation but Hesselbach’s ligament is somewhat more tenuous and, in fact, may be completely absent as the medial border of the internal ring. The transversalis fascia is the key structure in hernia repair since it provides the essential protection for the floor of the inguinal canal and the internal ring. The aponeurosis of the transversus abdominis reinforces the floor of the inguinal canal and may be fused with the transversalis fascia in this area. It inserts laterally by way of the lacunar ligament into Cooper’s ligament and medially into the rectus sheath. Rarely, it fuses with the aponeurosis of the internal oblique to form the conjoined tendon. However, in over 90 per cent of the specimens investigated a true conjoined tendon was absent and
Hospital, Diseases,
HE INGUINAL CANAL in its fUnCtiOn aS a conduit for the passage of the cord structures is the weakest portion of the abdominal wall. Either through congenital defect or by work atrophy, weakness in this area results in herniation of abdominal contents. This weakness is the result of functional dystrophy, and logical therapy is based on awareness of the functional structures which compose the groin area. The purpose of this report is to present a concept of the functional anatomy of the inguinal area in relation to the develqpment and treatment of groin hernias. A classification of groin hernias is proposed and appropriate surgical treatment for the repair of each type of hernia is described. The present data are reported on the basis of the operative findings and results in the repair of 854 groin hernias and upon numerous cadaver dissections.
T protective
FUNCTIONAL ANATOMY OF THE GROIN AREA The three principal functional structures in the inguinal area are the transversalis fascia, the transversus abdominis aponeurosis, and the iliopectineal or Cooper’s ligament. Other structures commonly employed in the repair of groin hernias, the internal oblique muscle and aponeurosis, the cremaster muscle, and the inguinal ligament, are not considered in the present context as functional structural units. 894
American
Journal
of
Surgery
Groin Hernias the insertion of transversus abdominis aponeurosis was independent of that of the internal oblique muscle. Transversus abdominis aponeurosis, when fused with transversalis fascia, forms a strong fascial layer which reinforces the floor of the inguinal canal. Therefore, in repair of inguinal hernias the transversus abdominis aponeurosis may be sutured to Cooper’s ligament but not to inguinal ligament since it has no normal attachments to inguinal ligament. Henle’s ligament arises from the aponeurotic insertion of transversus abdominis and strengthens the medial portion of the inguinal canal. However, this structure, too, may be tenuous and in many specimens is completely absent. The pectineal or Cooper’s ligament is a broad, thick, and strong fascial structure covering the superior pubic ramus from the pubic tubercle to the femoral vessels. To it is attached the iliopubic tract and transversus abdominis. The internal oblique is not inserted into Cooper’s ligament. This ligament is the posterior boundary of the femoral canal. Cooper’s ligament represents the site of fascial aponeurotic attachment and should be used in the repair of groin hernias in cases in which the floor of the inguinal canal has been destroyed by attenuation or work atrophy. There are several minor structures in the inguinal canal commonly used in the repair of groin hernia but which, according to the present concept, are not basic structural units and are not functional in the repair of these hernias. Of these, the internal oblique muscle is first considered. This arises from the lumbodorsal and iliopsoas fascia with the cremaster muscle and arches over and protects the internal ring, inserting into the rectus sheath as an aponeurotic sheet. Rarely it forms a conjoined tendon with the transversus abdominis. It overlies the internal ring and, in contracting, it protects this ring by sphincteric action. Fixation of this muscle by suture destroys this muscular sphincter and therefore has no place in the repair of inguinal hernias. The external oblique aponeurosis is the aponeurotic insertion of the external oblique and forms the roof and lateral boundary of the inguinal canal as well as the anterior border of the femoral ring. Split fibers of its insertion form the external ring. Neither the internal oblique nor the transversus abdominis muscle is attached to this ligament and should not be Vol. 114, December
1967
895
sutured to it in inguinal hernia repair. The external oblique aponeurosis is functionally indifferent and presents no barrier to the formation or progress of inguinal hernias since complete excision of this structure, as in radical groin dissection, does not result in hernia if the transversus abdominis and transversalis fascia are sutured to Cooper’s ligament. The present concept emphasizes the absence of structural or functional capacity of the external oblique aponeurosis and therefore eliminates this structure as a structural unit in hernia repair. The conjoined tendon is largely an ephemeral structure which is occasionally formed by fusion of the aponeurosis of the internal oblique and transversus abdominis as they insert into the pubic tubercle. When present (in approximately 10 per cent of the patients), it is rarely more than a few centimeters long and has no clinical significance in the repair of groin hernias. Internal oblique aponeurosis may reach the pubic tubercle but inserts primarily into the rectus sheath. The insertion of the transversus abdominis and Henle’s ligament may be mistakenly called the conjoined tendon. The cremaster muscle arises from the internal oblique at the iliopsoas fascia and separates from this muscle to form a covering for the cord structures. It is in no way functional and serves no purpose in the repair of inguinal hernias. It may be excised completely to present a clearer definition of the internal ring for purposes of closure of this structure during the repair of indirect inguinal hernia. The treatment of the hernial sac requires some elaboration. There is considerable variation in the pathogenesis of the indirect and the direct sac. The indirect sac is a congenital anomaly due to persistence of the processus vaginalis. As this structure enlarges, it weakens the internal ring. It presents as a structural defect and should be radically excised in the repair of indirect hernias. On the other hand, the direct sac is the result and not the cause of direct inguinal hernias. It results from weakness and attenuation of the transversalis fascia which forms the floor of the inguinal canal at Hesselbach’s triangle. The sac then presents as a secondary manifestation of this weakness. During the repair of direct hernias the sac must be completely liberated and reduced but need not be opened. It is our present
Casten
896
IOHYPOGASTRIC N.
TRANS. FASCIA
2
1 FIG. 1. Stage I hernia repair.
FIG. 2. Stage I hernia repair. Exposure of the inguinal canal. FIG. 3. Stage I hernia repair. Excision of the cremaster muscle and retraction
practice to reduce the direct sac without ‘excision of this structure. CLASSIFICATION
AND TREATMENT
OF
GROIN HERNIAS
On the basis of the preceeding brief anatomic considerations, a classification of groin hernias is presented which forms the basis for the surgical treatment of the various types of hernias presenting in this area. In presenting this classification, stress is placed on correction of the underlying functional deficit resulting in the development of each type of groin hernia. Although no mention has been made of femoral hernias, it is believed that the simple attenuation of transversalis fascia covering the femoral ring is responsible for the development of femoral hernias. Careful exploration of the femoral canal during the repair of inguinal hernias has indicated that in the absence of femoral hernias this ring is protected by a thin layer of transversalis fascia which adequately prevents the protrusion of the abdominal contents through this opening. Stage I hernias are defined as indirect inguinal hernias in patients (usually infants and children) in whom the internal ring is perfectly normal in size, configuration, and structure. The boundaries are well marked and in most instances both Hesselbach and Thomson’s ligaments are well defined. The simple anatomic defect is the presence of an indirect hernial sac. This is usually congenital, but it is possible
of the ilioinguinal nerve.
that in some patients a small unobliterated processus vaginalis may provide the nidus for the subsequent development of a larger indirect hernia without distortion of the internal ring. Treatment is based on correction of the simple anatomic defect, namely, the presence of a sac. In children it is usually not necessary to open the entire inguinal canal. The usual skin incision is made (which may be either transversely or obliquely placed) and the two or three constant vessels in the subcutaneous fat between skin and superficial fascia are exposed. These are the superficial epigastric vessels, the superficial external pudendal vessels, and occasionally superficial circumflex iliac vessels. These are doubly ligated and divided. The external oblique is then exposed and a 3 cm. incision is made through this structure directly over the internal ring. (Fig. 1.) The edges of this incision are retracted and the hernial sac is readily exposed lying anterior and medial to the cord structures. The sac is grasped with a fine forceps and dissected free from the cord structures. The cord structures are not disturbed or lifted from their normal position. As dissection is continued cephalad, the filmy attachments of the sac to the cremaster are divided by sharp dissection. The internal ring is clearly exposed by retraction of the internal oblique muscle cephalad. The sac is dissected down to its intra-abdominal portion. It is .then transfixed with No. 4-O silk suture and the American Journal
of Surgery
Groin Hernias
897
I IT. OBLIQUE Y.
.i 4
5
6
FIG. 4. Stage I hernia repair. High ligation of the sac.
FIG. 5. Stage internal ring.
II
hernia repair. High ligation of the sac, ligation of the external spermatic vessel, and exposure of the
FIG. 6. Stage
II
hernia repair. Closure of the internal ring.
excess sac is removed. The internal ring is inspected and is found to be normal. The cut edges of the external oblique are approximated with two or three sutures of No. 4-O silk. The skin may be closed with a subcuticular suture of fine silk. In older patients and particularly in those with somewhat larger hernias the external oblique is opened to the external ring. The ilioinguinal and iliohypogastric nerves are exposed and preserved. (Fig. 2.) The joined origin of internal oblique muscle and cremaster muscle is readily demonstrated. The cremaster may be excised if necessary. (Fig. 3.) The sac is then mobilized and dissected free from the cord structures. At the internal ring it is freed completely from its attachments. At this point it may be opened and inspected or may be twisted and transfixed with a No. 4-O silk suture high at the intra-abdominal portion. High ligation of the sac above the internal ring is mandatory. (Fig. 4.) The excess portion of the sac is removed. The internal ring is now inspected and in these patients it is found to be normal. The external oblique is approximated over the cord structures with interrupted sutures of No. 3-O silk. Skin closure is in the usual fashion. In the present series eighty-six operations were performed for stage I hernias. In no patient was the internal ring sutured. There were no recurrences in the group, Vol. 114
December
1967
Stage 1I hernias are defined as indirect inguinal hernias in patients in whom the internal ring is enlarged and distorted. The sac may be congenital or acquired. The edges are not as well formed as in stage I hernias but may be clearly observed. Commonly, a firm iliopubic tract can be demonstrated but Hesselbach’s ligament may be indistinct or absent. Sliding hernias of sigmoid or cecum are usually classified as stage II hernias since these are commonly indirect inguinal hernias. Although the treatment of the sac may be modified in the treatment of sliding hernias of the indirect variety, the basic principles of repair are unvarying. The technic of repair in stage II hernias is based on the recognition of the disability related to the enlarged and distorted internal ring. As an aid in exposure, the cremaster muscle is frequently excised. The cord structures are lifted and retracted and the sac is readily exposed in its medial and anterior portion. The external spermatic vessels arising from the inferior epigastric vessles are exposed and divided between suture ligatures of No. 4-O silk. After excision of the cremaster muscle the sac is readily dissected to its exit from the internal ring. At this point the sac is opened and the contents are reduced. High ligation of the sac is accomplished as in the preceding technic. A transfixion suture of No. 3-O silk or interrupted sutures of No. 3-O or
Casten
898
INTERNAL RING
~RANS.FASW 7 FIG. 7. Stage III hernia repair. Mobilization
COOPER'S LIG. 8 of the sac.
FIG. 8. Stage III hernia repair. Suture of the medial aponeurotic FIG. 9. Sage
III hernia repair. Transitional
COOPER'S LIG. 9 structure of Cooper’s ligament.
suture and repair of the internal ring.
4-O may be used for closure of the sac. (Fig. 5.) The internal ring is now exposed by retraction of the cord structures. The sac has retracted within the abdominal cavity. The internal oblique muscle may be retracted medially and cephalad for better exposure of the internal ring. The edges of the ring are now approximated with interrupted sutures of No. 3-O or 4-O silk. (Fig. 6.) The aponeurosis of the internal oblique and the shelving edge of the inguinal ligament are never utilized in this repair. The insertion of transversalis fascia as Thomson’s ligament into Cooper’s ligament can be readily demonstrated at this stage of the exposure. From three to six sutures are placed in the edges of the internal ring leaving the resulting aperture adequate for the exit of the cord structures. The veins of the spermatic cord are not excised. The cord is then dropped back into its normal position and the external oblique approximated over the cord structures with interrupted sutures of No. 3-O silk. The skin is closed in the usual fashion. Four hundred eighty-four operations of this type were carried out in this series for stage II hernias. There were four recurrences or 0.8 per cent in this group of patients. Reoperation on these patients disclosed that in three patients a direct sac had been overlooked and in one patient there was a recurrence as an indirect hernia. Stage III hernias are defined as all direct and femoral hernias. The inclusion of femoral
hernias in this stage is related to the fact that the proposed repair for femoral hernias is identical to that of all stage III or direct hernias. These hernias are always acquired and represent work atrophy or attenuation of the transveralis fascia which normally protects the floor of the inguinal canal in the area of Hesselbach’s triangle. Operative repair of stage III hernias is performed through the usual exposure of the inguinal canal. Careful inspection of the internal ring is made to exclude the presence of a coexistent indirect hernia. If none is found, the cord structures are mobilized and retracted laterally. The large bulge in Hesselbach’s area now delineates the presence of a direct hernia. A circumferential incision is made through the attenuated transversalis fascia which covers the sac. (Fig. 7.) This attenuated transversalis fascia which has been circumscribed is now removed exposing the preperitoneal fat covering the hernial sac. After removal of this circumscribed fascia the sac is readily reduced within the abdominal cavity. Careful inspection now reveals a sharp medial edge of transversalis fascia bounding the defect. Occasionally the aponeurosis of the transversus abdominis is fused with transversalis fascia. Tracing this edge medially and inferiorly leads to the lacunar ligament which can now be readily demonstrated as the insertion of transversus abdominis aponeurosis into Cooper’s ligament. Cooper’s ligament is readily exposed by retracting the reduced sac medially and cephalad. The femoral American
Journal
of Swgery
Groin vessels are now clearly seen at the lateral margin of Cooper’s ligament. Repair is effected by suturing transversalis fascia or fused transversalis and transversus abdominis aponeurosis to Cooper’s ligament. (Fig. 8.) The first suture is placed through the lacunar ligament to close securely the lower innermost portion of the canal. Sutures are then placed serially between the fused medial structures and Cooper’s ligament until the area of the retracted femoral vessels is reached. Approximately four to seven sutures are usually required; No. 2-O silk is used for these sutures. At this point it is necessary to reduce the size of the internal ring. The medial edge of transversalis fascia at the internal ring which has been previously demonstrated is now sutured to the iliopubic tract. The first suture is placed between transversalis fascia, Cooper’s ligament, and the iliopubic tract or femoral sheath. This is called the transitional suture and closes effectively the area between the two diverging lines of sutures. (Fig. 9.) Sutures are then placed serially between the transversalis fascia and iliopubic tract until the internal ring is sufficiently narrowed. The importance of the transitional suture between transversalis fascia, Cooper’s ligament, and the iliopubic tract cannot be overstressed. It should be noted that in no patient in this series has it been necessary to incise transversus abdominis aponeurosis to effect a firm closure of the floor of the canal. It is believed that since transversalis fascia in this area is quite mobile, incision in the fused aponeurosis of insertion of internal oblique and transversus abdominis
Vol. 114. Decembev 1967
Hernias
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in no way releases transversalis fascia, nor is it necessary to release it. In those patients in whom transversus abdominis at its insertion is fused with transversalis fascia it has been the author’s experience that a snug repair can invariably be accomplished without the necessity of a relaxing incision. Two hundred eighty-five operations have been performed for stage III hernias. There were four recurrences or 1.4 per cent in this group of patients. Femoral hernias are repaired in a fashion identical to that described herein for direct inguinal hernias. Since the fusion of transversalis fascia and transversus aponeurosis to Cooper’s ligament by suture repair completely protects the femoral ring of which Cooper’s ligament is the posterior boundary, this repair is quite effective in curing femoral hernias. The sac is treated in a fashion similar to that described for direct hernia. CONCLUSION
Based on the analysis of the functional anatomy of the inguinal canal, a classification of groin hernias is proposed which forms the basis for treatment. The functional anatomy is described and the appropriate treatment described and depicted. It is believed that a higher cure rate may be anticipated by the exclusive use of functional structures in the repair of groin hernias and it has been found that these structures are readily available, may be sutured without tension and result in a high percentage of cures.