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Inguinal Herniorrhaphy in the Adult
~nguinal
Herniorrhaphy in the Adult ROBERT G. RAVDIN, M.D.*
THE operation of inguinal herniorrhaphy in the adult occupies a unique position among surgical procedures. Developed at the onset of the modem surgical era, it has been refined but in essential respects remains unaltered. Designed to repair a purely structural defect, it has never been seriously threatened by any alternative form of management, nor do preventative measures seem likely to supplant it. Carrying an almost negligible mortality and low morbidity, it is a commonplace procedure among surgeons of all degrees of training and experience, and its performance entails no particular distinction. Yet the fact that the surgical literature contains a steady component of contributions on the subject indicates that no entirely satisfactory solution has been effected. Relatively few of these contributions represent original concepts; writing for the most part has concerned itself with emphasizing anatomical variants, or proposing minor modifications, most of which have not been supported by convincing evidence of their superiority. Nevertheless, the operation is in the main a successful one, and there is general agreement as to the principles involved. The present articl~ proposes to discuss these, without attempting to champion any technical idiosyncrasy whose choice must be considered essentially arbitrary on the basis of objective evidence. In order to clear the air as to the prejudices of the writer among the more contentious aspects of the subject, the following pomts of view are expressed explicitly and will be followed throughout. 1. Many failures can be traced to the surgeon's misdiagnosis of the nature of defect at operation, rather than to an inadequate repair. 2. The use of foreign substances, homografts, and autografts instead of the tissues normally present is in general unneccessary and in fact undesirable, with the few exceptions to be enumerated. The reader is referred to specific articles for techniques of this nature. 3. The preservation of normal structural relationships, in particular the inguinal "shutter," is desirable, especially when dealing with
* Assistant Professor of Surgery, School of Medicine, University of Pennsylvania; Surgical Staff, University of Pennsylvania Hospital; Consultant, Veterans Administration Hospital, Philadelphia, Pennsylvania. 16G3
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"congenital" herniation, i.e., herniation into the cord at the internal ring. But herniation through the floor of the inguinal canal (direct) has demonstrated the inadequacy of this mechanism, and strengthening the defect takes priority over other considerations; the writer thus describes the Halsted type of repair, with subcutaneous transplantation of the cord, as the procedure of choice for most direct hernias. Anesthesia constitutes a minor problem in herniorrhaphy; local, spinal or general can be used satisfactorily, the choice being based on the patient's other medical problems, or, when these afford no clear indications, on the surgeon's taste. Spinal has the advantage of giving better relaxation, but thereby makes the gauging of tension more difficult. EXPOSURE
Access to the inguinal region is attained through a skin incision either paralleling the inguinal ligament and one to two fingerbreadths above it, or placed more transversely so as to conform to Langer's lines, crossing the ligament at about its midpoint. The former has the merit of directly overlying the succeeding incision in the external oblique muscle, so that it may be slightly shorter, but it is less likely to result in a neat scar. In either event the incisions need not be extended farther medially than the pubic tubercle; to do so incurs more bleeding from the veins of the mons veneris than is necessary, and occasionally to troublesome phlebitis in this region. Laterally some three fingerbreadths will be needed, beyond the internal ring. After ligating superficial veins, the wound is draped and skin instruments discarded. Infection in this wound should be zealously avoided; it is inexcusable to jeopardize the outcome by suppuration. A strip of external oblique aponeurosis two fingerbreadths wide is exposed from the attachments of the pillars of the external ring laterally to the full extent of the skin incision. With the ring thus delineated, a point is selected in its lateral margin slightly cephalad of the midpoint, and a slit made a short distance away in the parallel aponeurotic fibers which lead to the selected area. This will leave an adequate margin of the inferior (shelving) edge of the inguinal ligament for the subsequent repair. A blunt instrument or finger introduced through the slit frees the underside of the aponeurosis from areolar tissue up to the margin of the ring. The slit is then extended medially to open the external ring and laterally well beyond the internal. The respective borders of the incised aponeurosis are grasped at several points with toothed clamps and separated widely with further blunt dissection of areolar tissue. This maneuver serves to bring into view the internal oblique muscle with its aponeurotic insertion into the rectus sheath, the cord lying in the unroofed inguinal canal, though still covered in part with cremaster muscle, and the branches of T -12, which should be identified. Neither of
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these is in much danger at this stage; the ileohypogastric clings to the internal oblique until it rises to pierce the external aponeurosis, usually a short distance cephalad to the external ring; the ilioinguinal is loosely attached to the cord and emerges with it through the ring. The latter, therefore, is best retracted with the cord; the former should be freed if it is lying near the lower margin of the internal oblique and retracted with the external aponeurosis. Both these nerves are far more likely to be injured by sutures during the repair than during exposure. The spermatic cord is now raised from the canal by incision of the cremasteric fibers between the ilioinguinal nerve and the inguinal ligament and passing a finger medially along the inner surface of the inguinal ligament to its insertion to the pubic tubercle. The entire cord can be lifted at this point, whereas an attempt to encompass it completely in the canal itself may fail because of the difficulty in delineating the posterior wall of the canal. Having elevated the cord at the tubercle, it is freed laterally to the internal ring by brushing the cremasteric fibers from its superior surface and dividing the areolar bindings to the transversalis fascia behind. A retractor placed beneath the inferior edge of the internal oblique at the internal ring, and drawn laterally and upward, and a tape around the cord drawing it downward and medially, complete the exposure. The deep epigastric vessels should now be readily seen; a small arterial branch is likely to be cut as the cord is separated at the internal ring. ASSESSMENT OF THE DEFECT
Although the site of herniation may now be obvious, it is clear that at least a considerable proportion of failures is due to lack of recognition of either the primary or an associated weakness. It is important, therefore, that all the possible sites of herniation be thoroughly explored. These are: (1) The internal ring, emerging in the cord itself (indirect); (2) the base of Hesselbach's triangle (direct); (3) the femoral canal; (4) the medif1l border of Hesselbach's triangle, or the lateral border of the rectus sheath (usually classified with direct, sometimes as supravesical or spigelian). Hernias in these areas comprise the vast majority, other lesions (lateral to the cord, or along the femoral vessels) being far less common. Herniation through the internal ring produces a sac which lies within the spermatic cord. To identify it, the cord should be formally opened by incision of cremasteric and internal spermatic fascial fibers in a longitudinal direction along the superior medial margin of the cord, where the sac may be expected to lie. These structures generally form a distinct layer whose margins may be retracted; beneath lies properitoneal fat which signals underlying peritoneum, when a sac is present. Since the internal spermatic fascia is continuous with the transversalis fascia, the incision will be closed subsequently to tighten the internal
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ring. With the cord opened in this fashion down to the internal ring, the absence of a sac can be demonstrated by placing a finger behind the cord, pushing the posterior wall forward, and displaying each of its various contents in turn as it is spread sheetlike over the finger. A direct hernia presents as a weakness in the floor of the canal caudad to the retracted lower edge of the inferior oblique. The retaining structure here is transversalis fascia, which must be disrupted to permit herniation. A defect allows the finger to be introduced at will retroperitoneally on the abdominal side of the superior ramus of the pubis. The margins of the defect in the transversalis fascia can usually be clearly identified, its fibers paralleling those of the inguinal ligament. Frequently these fibers run out over the neck of a direct sac, from which they can be readily separated because of intervening fat. A large direct sac is likely to fuse with the posterior surface of the spermatic cord, but separation can be achieved easily, and the fact that the cord need not be opened to get at the sac, as well as the position of the sac's neck with reference to the deep epigastric vessels, makes the nature of the hernia clear. To find a femoral sac, the interval between the inferior edge of the inguinal ligament and the superior ramus of the pubis is explored. In the presence of a direct hernia this region is entered without difficulty; a finger cannot then be passed from the pubic tubercle to the femoral vessels if there is an intervening sac. When the floor of the inguinal canal is intact, the attachment of transversalis fascia to the inguinal ligament may have to be separated to obtain the space (vide infra transversalis fascia), in which instance it should be subsequently repaired, or attached to Cooper's ligament. When a femoral sac is present, it is extremely unlikely to be reduced out of the canal inadvertently during the exposure, being adherent below almost always; in this event, the patulence of the femoral canal will be obvious if looked for. Herniation along the margin of the rectus sheath is not uncommon, and should be sought in the aponeurosis of the internal oblique by retracting the overlying external oblique aponeurosis which does not fuse until well across the rectus muscle. The border of the ring here will be sharp, and well defined, since it is tendinous (vide, infra, conjoined tendon). MANAGEMENT OF THE SAC
Having ascertained what defect or defects are involved, the operator now disposes of the redundant peritoneum. An indirect sac is opened, its cut edge is grasped with clamps and pulled over one or two fingers inserted into the cavity, and the adherent cord structures dissected free by sharp and blunt dissection. Veins of the pampiniform plexus are particularly prone to cling tightly and are less likely to be injured if they are first freed by a feathering motion of the knife before being brushed away. The distal portion of the sac is freed
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first: traction of this in one direction while gently drawing the cord in another greatly facilitates the dissection. The position of the vas should be constantly in mind. When the hernia is complete, or extends well into the scrotum, it is unnecessary to excise the entire sac: it may be transected leaving the distal part in situ, but this should not be closed. The dissection should continue to within the internal ring, often better identified by feel than sight, further opening the sac if necessary. Peritoneum should be pulled down from the parietes, to assure high ligation. The interior of the sac is inspected, and any adherent contents released and reduced. The opportunity is taken to introduce a finger into the peritoneal cavity to further assess any possible additional herniation, especially in the direct area, as a direct sac can now be pulled beneath the deep epigastric vessels and excised with the indirect. Then, under direct vision, a transfixion suture is passed through the sac below the neck. It is convenient to tie this down over the inserted finger, which is gradually withdrawn to prevent catching bowel or omentum in the ligature. A second transfixion ligature is placed distal to the first, and the excess sac excised. Alternatively, a purse-string may be used first, especially if the neck of the sac is wide. Many surgeons leave the ends of the second transfixion suture long, rethread them on large needles, and pass them individually from below upwards through the internal oblique in a cephalad and lateral direction, so that when they are tied down they draw the neck of the sac away from the inguinal canal. This procedure is logical only when the sutures can also be passed below the transversalis fascia; otherwise the stump will be drawn through the internal ring which cannot then be tightened. It is very desirable to close transversalis fascia over the stump snugly about the spermatic cord. If when on opening the sac of an indirect hernia, large bowel is seen to form one of its walls (sliding hernia), obviously no attempt should be made to free the serosa of the bowel; the colon must be dissected from the cord intact, along with its blood supply. This bowel is retroperitoneal, so that it will lie in the posterior aspect of the sac. It may be reduced from this approach, and some redundant peritoneum excised, but the results are notoriously poor with repair by this means alone. Entering the abdomen offers three advantages: the peritoneum is raised away from the inguinal region and the redundant portion more satisfactorily excised; the mesentery of the bowel is reconstituted, so that the bowel no longer lies retroperitoneally; the internal ring can be repaired more adequately with the assurance that bowel has been well removed from its vicinity. To accomplish this, the incision in the external oblique is extended laterally into the fleshy fibers of the muscle, allowing it to be retracted enough to expose the internal oblique for a distance of three or four fingerbreadths above the inguinal region. At this point the abdomen is entered through a muscle-splitting incision in internal
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oblique and transversalis. The colon, right or left, is drawn out of the wound; the herniated portion, if previously difficult of dissection, can be readily freed by combined approach through both exposures. With the colon exteriorized, the original opening in the sac will now appear as a slit in the lateral leaf of the mesentery of the herniated portion, i.e., that part of the serosa of the mesocolon which is continuous with the parietal peritoneum. Traction on the caudal margin of this slit pulls the peritoneum away from the hernial orifice and elevates the peritoneal floor; redundant serosa is now excised, if necessary to the extent of joining the mesenteric slit to the incision in the parietal peritoneum. The rent in the mesentery is closed with a running suture which also passes through to the medial leaf of serosa so as to reconstitute the mesentery and restore the colon from its retroperitoneal position to an intraperitoneal structure. The internal ring is best closed at this point, snugly about the cord by approximation of transversalis fascia, before closing the abdomen in the usual fashion for a McBurney incision. A direct sac need not be excised when it is not large, and when the neck is not narrow and sharply defined. When the weakness is diffuse and the sac essentially a bulge, it is convenient simply to invert it with the finger or a tape, and close the transversalis facia with a running suture over it, the stitches running at right angles to the fibers which parallel the inguinal ligament. This will serve to maintain the reduction before any further strengthening of the posterior wall of the canal is done. As previously noted, if any indirect sac is found concurrently, the direct sac can be drawn beneath the deep epigastric vessels and excised with the indirect. When the direct sac is large, descending into the scrotum or fusing with the cord, and when the hernial defect is sharply defined, it is generally preferable to excise the sac. The transversalis fascia should be dissected from the neck of the sac onto which it commonly spreads, and the sac with its liberal covering of properitoneal fat drawn forward to pull down parietal peritoneum. It is then opened, its contents freed if necessary, and cut away, grasping parietal peritoneum with clamps, and commencing the excision on the lateral surface so as to be able to define the position of the bladder as the medial surface is approached. The bladder may slide into a direct sac and care must be taken to avoid injuring it. Several bleeding points in the enveloping fat will require ligation. The rather large defect in the peritoneum is closed in the fashion of an abdominal incision, rather than by a transfixion ligature. The sac of a femoral hernia should be excised with care to include its neck where reaction has often led to fibrosis and sharp contours. It is withdrawn from the femoral canal by traction and sharp dissection, though some surgeons have suggested simply transection, leaving the distal sac to plug the canal. In the absence of active inflammation this plan would seem to have no disadvantages. When the contents are incarcerated, as is commonly the case, the contents should be released
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by cutting the ring at the canal medially, i.e., through Gimbernat's ligament, rather than laterally, where the femoral vein will be endangered. If this fails, one need not hesitate to cut the inguinal ligament. It may also facilitate the release of incarcerated bowel to undermine the lower skin margin in the plane of the deep fascia of the thigh and approach the sac also from the fossa ovalis. It may be added that to use the lower approach only in dealing with femoral hernia prevents the operator from searching for other herniation, leads to a less secure repair, and makes it exceedingly difficult if not impossible to manage compromised bowel. Herniation along the rectus sheath, high in Hesselbach's triangle, results in a well defined sac which presents no particular problems, being simply excised below the level of the fascia after transfixion. EVALUATION OF THE STRUCTURES AVAILABLE FOR RECONSTRUCTION
To this stage the operation has proceeded along well defined lines, but the point of divergence has now been reached, when discrepancies in the approaches to herniorrhaphy become apparent. The operator must decide what structures are available for the repair of the hernial defects he has encountered, and whether additional material will have to be introduced into the wound to support the repair. This writer feels that the use of foreign substances, either of autogenous origin, such as cutis or fascia, or of extraneous nature, such as tantalum mesh or silk floss, is justified only under unusual circumstances, and will present the issue from this point of view. Unless (1) the defect is exceedingly large, (2) the anatomy has been distorted and structures destroyed by previous repair or (3) the tissues are greatly attenuated by age or debilitation, the risk of infection and its consequences outweigh any extra security offered by prosthetic devices. It is fair to say that by no means all surgeons are in agreement with this thesis; but the fact that none of the numerous plans for the use of prostheses has gained wide currency in this country would suggest that the results of their proponents cannot be duplicated by others. The basis for successful repair is the transversalis fascia, which forms the internal ring and invests the properitoneal fat in the area of direct weakness. This structure is identified first. As noted before, it is usually apparent around the neck of a direct sac, from which it can be dissected and used for inversion of the sac itself. At the internal ring it will be found continuous with the internal spermatic fascia on opening the cord to find an indirect sac. The assertion of Anson and McVey that this fascia inserts into Cooper's ligament seems to this writer confusing; it is apparent, for instance, in exploring the area on a young patient with a simple indirect hernia, that there is a firm fascial layer in the floor of the inguinal canal, and that to expose the interval between the
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inguinal ligament and the superior ramus of the pubis this fascia in many instances must be deliberately opened. Some fascial continuity clearly exists between the inguinal ligament and the investing fascia. Many small direct defects also exhibit the fusion of fascia at their inferior margins with the inguinal ligament. On the other hand, the existence of fascia in the femoral area, where its fusion with the peritoneum forms the sharp margin characteristic of the neck of the femoral hernia, is also obvious. Whatever the actual situation may be, the important thing is to identify, whenever possible, an inferior fascial layer to which the transversalis from above can be anchored. The floor of the canal may need additional support from fascial layers, the next of which is obviously the "conjoined tendon," a structure which has also been subjected to considerable critical scrutiny. The essential point here would seem to be the extent to which the transversus abdominus and the internal oblique become aponeurotic. At times these muscles reach the rectus sheath as fleshy fibers, whereas they may become aponeurotic well before they reach the lateral edge of this muscle. In the latter case the use of the term "conjoined tendon" is ligitimate. In either event, however, a fibrous layer will be apparent which can usually be attached below to cover the floor of the canal. As is generally the case in the McBurney incision, where the transversus will be found to be aponeurotic beneath the more medial fleshly fibers of the internus, so white tissue may be found beneath the internus muscle in the inguinal region when its lower edge is lifted. Whatever name is given to the aponeurotic development of these two muscles, it is obviously advantageous to use this in repair rather than the muscle itself. The importance of the "shutter mechanism" for containing the inguinal region is speculative, but the likelihood of sutures pulling out of muscle is not. It is when the fibrous tissue available is inadequate to fill the defect that repairs using other substances must be considered. Certainly the most difficult factor to estimate is the tension the proposed repair will be under; spinal anesthesia will facilitate the apposition, but render the evaluation of tension after anesthesia has worn off more difficult. Experience only can guide this decision. The choice of attachment below must be made between the inguinal and Cooper's ligaments. Cooper's ligament, which may be considered a proliferation of the periosteum of the superior ramus of the pubis, offers the advantages of security, due to its strength, of leading to a simultaneous repair of the femoral area, and, according to McVey, of resulting in a more anatomical anchorage by following the attachment of the transversalis fascia (see above). Its disadvantages are mainly those of inaccessibility: it may be difficult of exposure in an obese patient, and its use requires careful avoidance of the femoral vein. The inguinal ligament affords simplicity and slightly less tension, and can be sutured in such a fashion as to result in a broader fascia-to-fascia ap-
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proximation. When the inguinal ligament has been destroyed or frayed by previous repair, when it is poorly developed, when there is a femoral defect, or when sturdy transversalis fascia cannot be found, Cooper's ligament is preferable. For simple indirect hernia in young individuals, where repair of the canal is arbitrary, the inguinal ligament should be used. In other instances, at the risk of offending enthusiasts, the writer considers the choice a matter of taste. REPAIR
Repair of an indirect hernia requires that after the excision of the sac, the internal ring be tightened snugly about the emerging cord. The difficulties involved depend on the extent of the defect: a simple hernia of short duration finds the ring small and .its investing fascia sound; a large or complete hernia of longer standing generally results in a diffuse defect with alternated and ill-defined fascial margins. In the former situation a few sutures effectively close the ring securely; it is tightened about the cord to admit only the tip of the little finger. The suture may be run out along the cord to close internal spermatic fascia; the opening in the cord serves as an effective guide to the margins of the ring, the fascia being continuous. The internal oblique and the transversus muscles are brought to lie more directly over the emerging cord by sewing their aponeurotic development to the inferior edge of the inguinal ligament laterally from the pubic tubercle for a distance of two or three fingerbreadths, which brings the muscle bellies to lie somewhat more obliquely. The cord is replaced in the canal, with care to reduce the testicle into the scrotum if it has been displaced during retraction of the cord. The external oblique aponeurosis is now closed with reconstruction of the external ring. This ring should also be closed to admit only the cord and the tip of the finger, not because the repair would otherwise be jeopardized, but because the presence of a patulous ring may be misconstrued as recurrence, especially during an examination for employment. This simple repair unfortunately may not suffice when the internal ring has been widely dilated, because the transversalis fascia may not of itself support the internal ring. Whatever exists of this structure should be closed about the cord. Additional support must be obtained from aponeurosis, which is approximated to the shelving edge of the inguinal ligament as far laterally as the ring itself. It is only when fibrous tissue is not available for this purpose that the use of fascial strips, tantalum mesh, silk lattice, or similar devices should be considered (and this is, in the writer's mind, very uncommonly). But to use muscle here, as noted above, is inviting failure, since it is likely to pull away. For this reason, the attachment of internal oblique to the shelving edse lateral to the cord, though sanctified by long usage, seems to the writer ill-advised; the lateral margin of the ring is usually intact, and
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strong, and if the muscle becomes torn, the strength of its medial continuation, essential to the repair, is weakened. Thus is described the classic Bassini repair. Choice of suture material has been deliberately avoided, since this is believed arbitrary. Silk and cotton should clearly be avoided in the presence of inflammation, i.e., strangulation; otherwise there is no evidence that these materials, gut, and wire are not interchangeable. The customary precepts of using the lightest appropriate material and closely spaced interrupted sutures are of course applicable. It is important to avoid fraying aponeurotic structures by staggering the needle bites, so that the same parallel bundles are not used for each suture. Precautions must be taken to identify the branches of the twelfth dorsal nerve during the repair, as including them in a suture at this stage will lead to more morbidity than dividing them during the exposure. Repair of a direct hernia depends on reinforcement of the floor of Hesselbach's triangle. Although, as noted above, the defect can be immediately contained by closing the transversalis fascia, this structure may be presumed inadequate to maintain the repair under stress by virtue of the previous herniation. Additional fascia must be drawn across the defect and anchored either to the inguinal or to Cooper's ligaments; the choice is guided by the considerations already discussed. When Cooper's ligament is used, the femoral vein must be clearly identified as it passes ventrally and protected by drawing it slightly laterally with the finger of the left hand. The femoral vein should not, however, be displaced so far that the subsequent sutures will result in encroachment on its lumen. The aponeurosis of the internal oblique and transversus is then sutured firmly down beginning medially and progressing laterally. In cramped exposures the placement of the last sutures is greatly facilitated by holding the more medial sutures untied until the entire row is placed. Then, since the internal ring is lateral to the vein, the aponeurosis is secured to the inferior border of the inguinal ligament in the remaining interval. The inferior margin of the original incision in the external oblique aponeurosis is now grasped with a toothed clamp, such as a Kocher, and pulled beneath the cord, so that it may also be used to support Hesselbach's triangle. The aponeurosis is then closed from the tubercle to the internal ring by sutures serving to imbricate it. (Particularly with imbrication, the sutures in the region of the tubercle, or the now obliterated external ring, are likely to catch the ileohypogastric nerve if it is not kept in view.) This closure is continued lateral to the cord, leaving just enough room to avoid venous compromise. This Halstead type of repair provides three fascial layers to fill the defect, and leaves the cord subcutaneous. Without question this type of repair produces more anatomical distortion than other forms; in the author's mind, this is justified by the additional strength obtained, and preservation of relationships demonstrably incompetent should not be
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the guiding principle. Again it must be emphasized that the maintenance of this repair depends primarily on the selection of structures which can be expected to hold it, as far more important consideration than minor technical modifications. The patient's permission to remove the testicle will enable the surgeon to close some of the more diffuse defects more efficiently by ligating the cord at the retroperitoneal level and avoiding the problem of leaving space at the internal ring. Direct defects toward the apex or along the medial border of Hesselbach's triangle pose little problem in closure: the ring is composed of aponeurosis and generally small, and the situation more comparable to ventral herniation through the linear or semicircularis (which, in effect, is the case). Excellent closure with imbrication is easily obtained, and recurrence uncommon. Femoral hernias call for closure of the femoral canal. This can be done by approximating the inguinal ligament to the pubic ramus, which is undoubtedly satisfactory when the transversalis fascia has been closed and the inguinal region is otherwise intact. The writer prefers McVey's procedure as described above, bringing the deep aponeurotic structures of the abdominal wall to Cooper's ligament, but leaving the cord in situ and reconstructing the external ring in the male. This protects against subsequent direct herniation, and provides more contiguous support for the herniated transversalis. The writer believes that a repair strong enough to permit ambulation should be accomplished, and that it is desirable to mobilij'le patients rapidly. When the repair is under some tension, hyperextension can be avoided by teaching the patient to get in and out of bed while lying on his face. Arching a patient over a bedpan is very undesirable. Support for the testes affords considerable comfort, as does support for the abdomen in the obese. 36th and Spruce Streets Philadelphia 4, Pennsylvania
Herniorrhaphy in the Adult ROBERT G. RAVDIN, M.D.*
THE operation of inguinal herniorrhaphy in the adult occupies a unique position among surgical procedures. Developed at the onset of the modem surgical era, it has been refined but in essential respects remains unaltered. Designed to repair a purely structural defect, it has never been seriously threatened by any alternative form of management, nor do preventative measures seem likely to supplant it. Carrying an almost negligible mortality and low morbidity, it is a commonplace procedure among surgeons of all degrees of training and experience, and its performance entails no particular distinction. Yet the fact that the surgical literature contains a steady component of contributions on the subject indicates that no entirely satisfactory solution has been effected. Relatively few of these contributions represent original concepts; writing for the most part has concerned itself with emphasizing anatomical variants, or proposing minor modifications, most of which have not been supported by convincing evidence of their superiority. Nevertheless, the operation is in the main a successful one, and there is general agreement as to the principles involved. The present articl~ proposes to discuss these, without attempting to champion any technical idiosyncrasy whose choice must be considered essentially arbitrary on the basis of objective evidence. In order to clear the air as to the prejudices of the writer among the more contentious aspects of the subject, the following pomts of view are expressed explicitly and will be followed throughout. 1. Many failures can be traced to the surgeon's misdiagnosis of the nature of defect at operation, rather than to an inadequate repair. 2. The use of foreign substances, homografts, and autografts instead of the tissues normally present is in general unneccessary and in fact undesirable, with the few exceptions to be enumerated. The reader is referred to specific articles for techniques of this nature. 3. The preservation of normal structural relationships, in particular the inguinal "shutter," is desirable, especially when dealing with
* Assistant Professor of Surgery, School of Medicine, University of Pennsylvania; Surgical Staff, University of Pennsylvania Hospital; Consultant, Veterans Administration Hospital, Philadelphia, Pennsylvania. 16G3
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"congenital" herniation, i.e., herniation into the cord at the internal ring. But herniation through the floor of the inguinal canal (direct) has demonstrated the inadequacy of this mechanism, and strengthening the defect takes priority over other considerations; the writer thus describes the Halsted type of repair, with subcutaneous transplantation of the cord, as the procedure of choice for most direct hernias. Anesthesia constitutes a minor problem in herniorrhaphy; local, spinal or general can be used satisfactorily, the choice being based on the patient's other medical problems, or, when these afford no clear indications, on the surgeon's taste. Spinal has the advantage of giving better relaxation, but thereby makes the gauging of tension more difficult. EXPOSURE
Access to the inguinal region is attained through a skin incision either paralleling the inguinal ligament and one to two fingerbreadths above it, or placed more transversely so as to conform to Langer's lines, crossing the ligament at about its midpoint. The former has the merit of directly overlying the succeeding incision in the external oblique muscle, so that it may be slightly shorter, but it is less likely to result in a neat scar. In either event the incisions need not be extended farther medially than the pubic tubercle; to do so incurs more bleeding from the veins of the mons veneris than is necessary, and occasionally to troublesome phlebitis in this region. Laterally some three fingerbreadths will be needed, beyond the internal ring. After ligating superficial veins, the wound is draped and skin instruments discarded. Infection in this wound should be zealously avoided; it is inexcusable to jeopardize the outcome by suppuration. A strip of external oblique aponeurosis two fingerbreadths wide is exposed from the attachments of the pillars of the external ring laterally to the full extent of the skin incision. With the ring thus delineated, a point is selected in its lateral margin slightly cephalad of the midpoint, and a slit made a short distance away in the parallel aponeurotic fibers which lead to the selected area. This will leave an adequate margin of the inferior (shelving) edge of the inguinal ligament for the subsequent repair. A blunt instrument or finger introduced through the slit frees the underside of the aponeurosis from areolar tissue up to the margin of the ring. The slit is then extended medially to open the external ring and laterally well beyond the internal. The respective borders of the incised aponeurosis are grasped at several points with toothed clamps and separated widely with further blunt dissection of areolar tissue. This maneuver serves to bring into view the internal oblique muscle with its aponeurotic insertion into the rectus sheath, the cord lying in the unroofed inguinal canal, though still covered in part with cremaster muscle, and the branches of T -12, which should be identified. Neither of
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these is in much danger at this stage; the ileohypogastric clings to the internal oblique until it rises to pierce the external aponeurosis, usually a short distance cephalad to the external ring; the ilioinguinal is loosely attached to the cord and emerges with it through the ring. The latter, therefore, is best retracted with the cord; the former should be freed if it is lying near the lower margin of the internal oblique and retracted with the external aponeurosis. Both these nerves are far more likely to be injured by sutures during the repair than during exposure. The spermatic cord is now raised from the canal by incision of the cremasteric fibers between the ilioinguinal nerve and the inguinal ligament and passing a finger medially along the inner surface of the inguinal ligament to its insertion to the pubic tubercle. The entire cord can be lifted at this point, whereas an attempt to encompass it completely in the canal itself may fail because of the difficulty in delineating the posterior wall of the canal. Having elevated the cord at the tubercle, it is freed laterally to the internal ring by brushing the cremasteric fibers from its superior surface and dividing the areolar bindings to the transversalis fascia behind. A retractor placed beneath the inferior edge of the internal oblique at the internal ring, and drawn laterally and upward, and a tape around the cord drawing it downward and medially, complete the exposure. The deep epigastric vessels should now be readily seen; a small arterial branch is likely to be cut as the cord is separated at the internal ring. ASSESSMENT OF THE DEFECT
Although the site of herniation may now be obvious, it is clear that at least a considerable proportion of failures is due to lack of recognition of either the primary or an associated weakness. It is important, therefore, that all the possible sites of herniation be thoroughly explored. These are: (1) The internal ring, emerging in the cord itself (indirect); (2) the base of Hesselbach's triangle (direct); (3) the femoral canal; (4) the medif1l border of Hesselbach's triangle, or the lateral border of the rectus sheath (usually classified with direct, sometimes as supravesical or spigelian). Hernias in these areas comprise the vast majority, other lesions (lateral to the cord, or along the femoral vessels) being far less common. Herniation through the internal ring produces a sac which lies within the spermatic cord. To identify it, the cord should be formally opened by incision of cremasteric and internal spermatic fascial fibers in a longitudinal direction along the superior medial margin of the cord, where the sac may be expected to lie. These structures generally form a distinct layer whose margins may be retracted; beneath lies properitoneal fat which signals underlying peritoneum, when a sac is present. Since the internal spermatic fascia is continuous with the transversalis fascia, the incision will be closed subsequently to tighten the internal
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ring. With the cord opened in this fashion down to the internal ring, the absence of a sac can be demonstrated by placing a finger behind the cord, pushing the posterior wall forward, and displaying each of its various contents in turn as it is spread sheetlike over the finger. A direct hernia presents as a weakness in the floor of the canal caudad to the retracted lower edge of the inferior oblique. The retaining structure here is transversalis fascia, which must be disrupted to permit herniation. A defect allows the finger to be introduced at will retroperitoneally on the abdominal side of the superior ramus of the pubis. The margins of the defect in the transversalis fascia can usually be clearly identified, its fibers paralleling those of the inguinal ligament. Frequently these fibers run out over the neck of a direct sac, from which they can be readily separated because of intervening fat. A large direct sac is likely to fuse with the posterior surface of the spermatic cord, but separation can be achieved easily, and the fact that the cord need not be opened to get at the sac, as well as the position of the sac's neck with reference to the deep epigastric vessels, makes the nature of the hernia clear. To find a femoral sac, the interval between the inferior edge of the inguinal ligament and the superior ramus of the pubis is explored. In the presence of a direct hernia this region is entered without difficulty; a finger cannot then be passed from the pubic tubercle to the femoral vessels if there is an intervening sac. When the floor of the inguinal canal is intact, the attachment of transversalis fascia to the inguinal ligament may have to be separated to obtain the space (vide infra transversalis fascia), in which instance it should be subsequently repaired, or attached to Cooper's ligament. When a femoral sac is present, it is extremely unlikely to be reduced out of the canal inadvertently during the exposure, being adherent below almost always; in this event, the patulence of the femoral canal will be obvious if looked for. Herniation along the margin of the rectus sheath is not uncommon, and should be sought in the aponeurosis of the internal oblique by retracting the overlying external oblique aponeurosis which does not fuse until well across the rectus muscle. The border of the ring here will be sharp, and well defined, since it is tendinous (vide, infra, conjoined tendon). MANAGEMENT OF THE SAC
Having ascertained what defect or defects are involved, the operator now disposes of the redundant peritoneum. An indirect sac is opened, its cut edge is grasped with clamps and pulled over one or two fingers inserted into the cavity, and the adherent cord structures dissected free by sharp and blunt dissection. Veins of the pampiniform plexus are particularly prone to cling tightly and are less likely to be injured if they are first freed by a feathering motion of the knife before being brushed away. The distal portion of the sac is freed
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first: traction of this in one direction while gently drawing the cord in another greatly facilitates the dissection. The position of the vas should be constantly in mind. When the hernia is complete, or extends well into the scrotum, it is unnecessary to excise the entire sac: it may be transected leaving the distal part in situ, but this should not be closed. The dissection should continue to within the internal ring, often better identified by feel than sight, further opening the sac if necessary. Peritoneum should be pulled down from the parietes, to assure high ligation. The interior of the sac is inspected, and any adherent contents released and reduced. The opportunity is taken to introduce a finger into the peritoneal cavity to further assess any possible additional herniation, especially in the direct area, as a direct sac can now be pulled beneath the deep epigastric vessels and excised with the indirect. Then, under direct vision, a transfixion suture is passed through the sac below the neck. It is convenient to tie this down over the inserted finger, which is gradually withdrawn to prevent catching bowel or omentum in the ligature. A second transfixion ligature is placed distal to the first, and the excess sac excised. Alternatively, a purse-string may be used first, especially if the neck of the sac is wide. Many surgeons leave the ends of the second transfixion suture long, rethread them on large needles, and pass them individually from below upwards through the internal oblique in a cephalad and lateral direction, so that when they are tied down they draw the neck of the sac away from the inguinal canal. This procedure is logical only when the sutures can also be passed below the transversalis fascia; otherwise the stump will be drawn through the internal ring which cannot then be tightened. It is very desirable to close transversalis fascia over the stump snugly about the spermatic cord. If when on opening the sac of an indirect hernia, large bowel is seen to form one of its walls (sliding hernia), obviously no attempt should be made to free the serosa of the bowel; the colon must be dissected from the cord intact, along with its blood supply. This bowel is retroperitoneal, so that it will lie in the posterior aspect of the sac. It may be reduced from this approach, and some redundant peritoneum excised, but the results are notoriously poor with repair by this means alone. Entering the abdomen offers three advantages: the peritoneum is raised away from the inguinal region and the redundant portion more satisfactorily excised; the mesentery of the bowel is reconstituted, so that the bowel no longer lies retroperitoneally; the internal ring can be repaired more adequately with the assurance that bowel has been well removed from its vicinity. To accomplish this, the incision in the external oblique is extended laterally into the fleshy fibers of the muscle, allowing it to be retracted enough to expose the internal oblique for a distance of three or four fingerbreadths above the inguinal region. At this point the abdomen is entered through a muscle-splitting incision in internal
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oblique and transversalis. The colon, right or left, is drawn out of the wound; the herniated portion, if previously difficult of dissection, can be readily freed by combined approach through both exposures. With the colon exteriorized, the original opening in the sac will now appear as a slit in the lateral leaf of the mesentery of the herniated portion, i.e., that part of the serosa of the mesocolon which is continuous with the parietal peritoneum. Traction on the caudal margin of this slit pulls the peritoneum away from the hernial orifice and elevates the peritoneal floor; redundant serosa is now excised, if necessary to the extent of joining the mesenteric slit to the incision in the parietal peritoneum. The rent in the mesentery is closed with a running suture which also passes through to the medial leaf of serosa so as to reconstitute the mesentery and restore the colon from its retroperitoneal position to an intraperitoneal structure. The internal ring is best closed at this point, snugly about the cord by approximation of transversalis fascia, before closing the abdomen in the usual fashion for a McBurney incision. A direct sac need not be excised when it is not large, and when the neck is not narrow and sharply defined. When the weakness is diffuse and the sac essentially a bulge, it is convenient simply to invert it with the finger or a tape, and close the transversalis facia with a running suture over it, the stitches running at right angles to the fibers which parallel the inguinal ligament. This will serve to maintain the reduction before any further strengthening of the posterior wall of the canal is done. As previously noted, if any indirect sac is found concurrently, the direct sac can be drawn beneath the deep epigastric vessels and excised with the indirect. When the direct sac is large, descending into the scrotum or fusing with the cord, and when the hernial defect is sharply defined, it is generally preferable to excise the sac. The transversalis fascia should be dissected from the neck of the sac onto which it commonly spreads, and the sac with its liberal covering of properitoneal fat drawn forward to pull down parietal peritoneum. It is then opened, its contents freed if necessary, and cut away, grasping parietal peritoneum with clamps, and commencing the excision on the lateral surface so as to be able to define the position of the bladder as the medial surface is approached. The bladder may slide into a direct sac and care must be taken to avoid injuring it. Several bleeding points in the enveloping fat will require ligation. The rather large defect in the peritoneum is closed in the fashion of an abdominal incision, rather than by a transfixion ligature. The sac of a femoral hernia should be excised with care to include its neck where reaction has often led to fibrosis and sharp contours. It is withdrawn from the femoral canal by traction and sharp dissection, though some surgeons have suggested simply transection, leaving the distal sac to plug the canal. In the absence of active inflammation this plan would seem to have no disadvantages. When the contents are incarcerated, as is commonly the case, the contents should be released
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by cutting the ring at the canal medially, i.e., through Gimbernat's ligament, rather than laterally, where the femoral vein will be endangered. If this fails, one need not hesitate to cut the inguinal ligament. It may also facilitate the release of incarcerated bowel to undermine the lower skin margin in the plane of the deep fascia of the thigh and approach the sac also from the fossa ovalis. It may be added that to use the lower approach only in dealing with femoral hernia prevents the operator from searching for other herniation, leads to a less secure repair, and makes it exceedingly difficult if not impossible to manage compromised bowel. Herniation along the rectus sheath, high in Hesselbach's triangle, results in a well defined sac which presents no particular problems, being simply excised below the level of the fascia after transfixion. EVALUATION OF THE STRUCTURES AVAILABLE FOR RECONSTRUCTION
To this stage the operation has proceeded along well defined lines, but the point of divergence has now been reached, when discrepancies in the approaches to herniorrhaphy become apparent. The operator must decide what structures are available for the repair of the hernial defects he has encountered, and whether additional material will have to be introduced into the wound to support the repair. This writer feels that the use of foreign substances, either of autogenous origin, such as cutis or fascia, or of extraneous nature, such as tantalum mesh or silk floss, is justified only under unusual circumstances, and will present the issue from this point of view. Unless (1) the defect is exceedingly large, (2) the anatomy has been distorted and structures destroyed by previous repair or (3) the tissues are greatly attenuated by age or debilitation, the risk of infection and its consequences outweigh any extra security offered by prosthetic devices. It is fair to say that by no means all surgeons are in agreement with this thesis; but the fact that none of the numerous plans for the use of prostheses has gained wide currency in this country would suggest that the results of their proponents cannot be duplicated by others. The basis for successful repair is the transversalis fascia, which forms the internal ring and invests the properitoneal fat in the area of direct weakness. This structure is identified first. As noted before, it is usually apparent around the neck of a direct sac, from which it can be dissected and used for inversion of the sac itself. At the internal ring it will be found continuous with the internal spermatic fascia on opening the cord to find an indirect sac. The assertion of Anson and McVey that this fascia inserts into Cooper's ligament seems to this writer confusing; it is apparent, for instance, in exploring the area on a young patient with a simple indirect hernia, that there is a firm fascial layer in the floor of the inguinal canal, and that to expose the interval between the
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inguinal ligament and the superior ramus of the pubis this fascia in many instances must be deliberately opened. Some fascial continuity clearly exists between the inguinal ligament and the investing fascia. Many small direct defects also exhibit the fusion of fascia at their inferior margins with the inguinal ligament. On the other hand, the existence of fascia in the femoral area, where its fusion with the peritoneum forms the sharp margin characteristic of the neck of the femoral hernia, is also obvious. Whatever the actual situation may be, the important thing is to identify, whenever possible, an inferior fascial layer to which the transversalis from above can be anchored. The floor of the canal may need additional support from fascial layers, the next of which is obviously the "conjoined tendon," a structure which has also been subjected to considerable critical scrutiny. The essential point here would seem to be the extent to which the transversus abdominus and the internal oblique become aponeurotic. At times these muscles reach the rectus sheath as fleshy fibers, whereas they may become aponeurotic well before they reach the lateral edge of this muscle. In the latter case the use of the term "conjoined tendon" is ligitimate. In either event, however, a fibrous layer will be apparent which can usually be attached below to cover the floor of the canal. As is generally the case in the McBurney incision, where the transversus will be found to be aponeurotic beneath the more medial fleshly fibers of the internus, so white tissue may be found beneath the internus muscle in the inguinal region when its lower edge is lifted. Whatever name is given to the aponeurotic development of these two muscles, it is obviously advantageous to use this in repair rather than the muscle itself. The importance of the "shutter mechanism" for containing the inguinal region is speculative, but the likelihood of sutures pulling out of muscle is not. It is when the fibrous tissue available is inadequate to fill the defect that repairs using other substances must be considered. Certainly the most difficult factor to estimate is the tension the proposed repair will be under; spinal anesthesia will facilitate the apposition, but render the evaluation of tension after anesthesia has worn off more difficult. Experience only can guide this decision. The choice of attachment below must be made between the inguinal and Cooper's ligaments. Cooper's ligament, which may be considered a proliferation of the periosteum of the superior ramus of the pubis, offers the advantages of security, due to its strength, of leading to a simultaneous repair of the femoral area, and, according to McVey, of resulting in a more anatomical anchorage by following the attachment of the transversalis fascia (see above). Its disadvantages are mainly those of inaccessibility: it may be difficult of exposure in an obese patient, and its use requires careful avoidance of the femoral vein. The inguinal ligament affords simplicity and slightly less tension, and can be sutured in such a fashion as to result in a broader fascia-to-fascia ap-
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proximation. When the inguinal ligament has been destroyed or frayed by previous repair, when it is poorly developed, when there is a femoral defect, or when sturdy transversalis fascia cannot be found, Cooper's ligament is preferable. For simple indirect hernia in young individuals, where repair of the canal is arbitrary, the inguinal ligament should be used. In other instances, at the risk of offending enthusiasts, the writer considers the choice a matter of taste. REPAIR
Repair of an indirect hernia requires that after the excision of the sac, the internal ring be tightened snugly about the emerging cord. The difficulties involved depend on the extent of the defect: a simple hernia of short duration finds the ring small and .its investing fascia sound; a large or complete hernia of longer standing generally results in a diffuse defect with alternated and ill-defined fascial margins. In the former situation a few sutures effectively close the ring securely; it is tightened about the cord to admit only the tip of the little finger. The suture may be run out along the cord to close internal spermatic fascia; the opening in the cord serves as an effective guide to the margins of the ring, the fascia being continuous. The internal oblique and the transversus muscles are brought to lie more directly over the emerging cord by sewing their aponeurotic development to the inferior edge of the inguinal ligament laterally from the pubic tubercle for a distance of two or three fingerbreadths, which brings the muscle bellies to lie somewhat more obliquely. The cord is replaced in the canal, with care to reduce the testicle into the scrotum if it has been displaced during retraction of the cord. The external oblique aponeurosis is now closed with reconstruction of the external ring. This ring should also be closed to admit only the cord and the tip of the finger, not because the repair would otherwise be jeopardized, but because the presence of a patulous ring may be misconstrued as recurrence, especially during an examination for employment. This simple repair unfortunately may not suffice when the internal ring has been widely dilated, because the transversalis fascia may not of itself support the internal ring. Whatever exists of this structure should be closed about the cord. Additional support must be obtained from aponeurosis, which is approximated to the shelving edge of the inguinal ligament as far laterally as the ring itself. It is only when fibrous tissue is not available for this purpose that the use of fascial strips, tantalum mesh, silk lattice, or similar devices should be considered (and this is, in the writer's mind, very uncommonly). But to use muscle here, as noted above, is inviting failure, since it is likely to pull away. For this reason, the attachment of internal oblique to the shelving edse lateral to the cord, though sanctified by long usage, seems to the writer ill-advised; the lateral margin of the ring is usually intact, and
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strong, and if the muscle becomes torn, the strength of its medial continuation, essential to the repair, is weakened. Thus is described the classic Bassini repair. Choice of suture material has been deliberately avoided, since this is believed arbitrary. Silk and cotton should clearly be avoided in the presence of inflammation, i.e., strangulation; otherwise there is no evidence that these materials, gut, and wire are not interchangeable. The customary precepts of using the lightest appropriate material and closely spaced interrupted sutures are of course applicable. It is important to avoid fraying aponeurotic structures by staggering the needle bites, so that the same parallel bundles are not used for each suture. Precautions must be taken to identify the branches of the twelfth dorsal nerve during the repair, as including them in a suture at this stage will lead to more morbidity than dividing them during the exposure. Repair of a direct hernia depends on reinforcement of the floor of Hesselbach's triangle. Although, as noted above, the defect can be immediately contained by closing the transversalis fascia, this structure may be presumed inadequate to maintain the repair under stress by virtue of the previous herniation. Additional fascia must be drawn across the defect and anchored either to the inguinal or to Cooper's ligaments; the choice is guided by the considerations already discussed. When Cooper's ligament is used, the femoral vein must be clearly identified as it passes ventrally and protected by drawing it slightly laterally with the finger of the left hand. The femoral vein should not, however, be displaced so far that the subsequent sutures will result in encroachment on its lumen. The aponeurosis of the internal oblique and transversus is then sutured firmly down beginning medially and progressing laterally. In cramped exposures the placement of the last sutures is greatly facilitated by holding the more medial sutures untied until the entire row is placed. Then, since the internal ring is lateral to the vein, the aponeurosis is secured to the inferior border of the inguinal ligament in the remaining interval. The inferior margin of the original incision in the external oblique aponeurosis is now grasped with a toothed clamp, such as a Kocher, and pulled beneath the cord, so that it may also be used to support Hesselbach's triangle. The aponeurosis is then closed from the tubercle to the internal ring by sutures serving to imbricate it. (Particularly with imbrication, the sutures in the region of the tubercle, or the now obliterated external ring, are likely to catch the ileohypogastric nerve if it is not kept in view.) This closure is continued lateral to the cord, leaving just enough room to avoid venous compromise. This Halstead type of repair provides three fascial layers to fill the defect, and leaves the cord subcutaneous. Without question this type of repair produces more anatomical distortion than other forms; in the author's mind, this is justified by the additional strength obtained, and preservation of relationships demonstrably incompetent should not be
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the guiding principle. Again it must be emphasized that the maintenance of this repair depends primarily on the selection of structures which can be expected to hold it, as far more important consideration than minor technical modifications. The patient's permission to remove the testicle will enable the surgeon to close some of the more diffuse defects more efficiently by ligating the cord at the retroperitoneal level and avoiding the problem of leaving space at the internal ring. Direct defects toward the apex or along the medial border of Hesselbach's triangle pose little problem in closure: the ring is composed of aponeurosis and generally small, and the situation more comparable to ventral herniation through the linear or semicircularis (which, in effect, is the case). Excellent closure with imbrication is easily obtained, and recurrence uncommon. Femoral hernias call for closure of the femoral canal. This can be done by approximating the inguinal ligament to the pubic ramus, which is undoubtedly satisfactory when the transversalis fascia has been closed and the inguinal region is otherwise intact. The writer prefers McVey's procedure as described above, bringing the deep aponeurotic structures of the abdominal wall to Cooper's ligament, but leaving the cord in situ and reconstructing the external ring in the male. This protects against subsequent direct herniation, and provides more contiguous support for the herniated transversalis. The writer believes that a repair strong enough to permit ambulation should be accomplished, and that it is desirable to mobilij'le patients rapidly. When the repair is under some tension, hyperextension can be avoided by teaching the patient to get in and out of bed while lying on his face. Arching a patient over a bedpan is very undesirable. Support for the testes affords considerable comfort, as does support for the abdomen in the obese. 36th and Spruce Streets Philadelphia 4, Pennsylvania