Vulvar-Vaginal Reconstruction

Trauma to the female perineum can occur from many different circumstances. The most common setting, of course, is vaginal delivery secondary to acute distention of the vaginal canal during passage of the fetus or to instrumentation during operative delivery. Non-obstetric trauma can result from "straddle injuries" resulting from abrupt contact with a structure such as a bicycle crossbar, "penetration injuries" resulting from impalement by the end of a hard rod-like instrument, or "complex injuries" resulting from blunt trauma. The focus of this article is evaluation and management of injury to the female perineum resulting from nonobstetric trauma.

United States statistics

The incidence of trauma to the female perineum sufficiently damaging enough to require active medical intervention is unknown. One series from the University of North Carolina Hospitals reported 29 cases admitted for treatment between 1975 and 1991.[1]

Perineal trauma, in general terms, occurs by one of the following mechanisms:

• During parturition, as the fetal head passes through the birth canal and vaginal introitus

• As the result of impact caused by acute deceleration injury (eg, straddle injury associated with falling on the crossbar of a bicycle)

• Insertion injury (eg, from forceful coitus, insertion of foreign body during sexual assault, impaling injury secondary to a fall)

• Penetrating injury, such as knife or gunshot

• Complex injury from blunt trauma

Blunt trauma to the perineum (eg, straddle injury, deceleration injury) results in rapid stretching of involved tissues at such a rate and to such a degree that tissue elasticity is insufficient to accommodate expansion, and the tissue tears. The depth and extent of laceration are determined by the rate of stretching, the nature of the trauma incurred, the location of the trauma, and the inherent elasticity of the affected tissue. By and large, the depth of the injury is limited to the superfical tissue of the perineum, as the soft tissues of the perineum and bony structures of the pelvis offer protection to deeper structures.

The female perineum is highly vascular.[2] Arterial blood supply is derived primarily from the terminal branches of the internal pudendal artery, which enters the perineum laterally near the ischial tuberosity, then divides into branches supplying the perianal and perivaginal tissue and the vestibular bulb. There are rich anastomoses with external arteries such as the posterior labial artery and the external pudendal artery. The perineum is drained by an extensive venous network, especially the erectile tissue of the labia majora and glans clitorus. These veins, which are not protected by valves, have multiple interconnections with the internal pelvic venous system. Even in the absence of epithelial laceration, blunt trauma to the perineum can result in significant tissue damage, such as hematoma formation, tissue crushing, and, possibly, devascularization because of compromise of local perfusion.[3]

When evaluating a patient who presents with lower abdominal trauma or pelvic trauma (eg, vehicle accident injuries, penetrating trauma to the lower abdomen) consideration must be given to the possiblity of perineal or internal genitalia injury. Being alert to such a possibililty is especially true of children. Because of the nature of their activites, it is not uncommon for them to sustain complex perineal injuries resulting from forceful contact with toys, etc., but they may be reticent to report this because of embarrassment.  

The possibility of remote trauma should be considered in the evaluation of a patient who presents with some form of perineal dysfunction, especially if there is some evidence of  a remote history of trauma. For example, a woman who has sustained damage during forceful coitus may be too embarrassed to seek evaluation until she is compelled to by her perineal pain. Other presenting complaints may relate to competence of the structures that pass through the perineum (eg, anus, urethra) or to discomfort with coitus.

When confronted with a patient who may have sustained traumatic injury, attempt to ascertain the nature and degree of the trauma to identify the extent of collateral damage that may have occurred. Otherwise, occult injury may pass unnoticed and remain uncorrected. Adequate evaluation of the extent of the injury and appropriate reconstruction is not possible without a comprehensive knowledge of perineal structural and vascular anatomy.

The objective of the evaluation is to determine expeditiously the nature and extent of injuries so that appropriate restorative therapy can be instituted as promptly as possible.

History and physical examination are the most useful diagnostic tools for evaluating a patient who has sustained perineal trauma. A detailed history, if obtainable, provides information regarding the location and probable extent of the injury. This enables the examiner to direct special attention to aspects of the perineum and vagina that are at increased risk because of the nature of the trauma. For example, a history of a straddle injury should direct attention toward disruption of the perineal body, anus, and distal urethra, whereas penetration injury should prompt consideration of possible damage to the vaginal canal and pelvic viscera.

The first objective of the physical examination is to ensure that the patient is hemodynamically stable. As noted previously, the pelvis is richly perfused. Extensive occult hemorrhage can occur in the large potential spaces of the pelvis, such as the ischiorectal fossa. Moreover, as is true of obstetric trauma, intravaginal penetrating injuries can disrupt the retroperitoneal vasculature, with resultant retroperitoneal and intraperitoneal hemorrhage.

For women who sustain significant perineal trauma in association with more general injuries, for example, from motor vehicle accidents, the possibility of cervical spine instability must be evaluated prior to any definitive evaluation or management of non–life-threatening injuries.

Once the patient is deemed stable, a thorough visual examination is made of the vulva and vagina for lacerations, ecchymosis, and fluctuance, followed by a bimanual evaluation for intrapelvic masses. In the special case of a woman who has experienced a severe deceleration injury (eg, straddle injury), the bony pelvic girdle must be palpated for tenderness or crepitation. The symphysis pubis, particularly, must be evaluated for stability.

The importance of a meticulous examination, under anesthesia if necessary, cannot be overemphasized. The full extent of injuries can only be assessed by a comprehensive survey. Implicit in this statement is the realization that the surface disruption may signal the possibility of damage to deeper structures; therefore, the success of such an evaluation depends on an intimate and detailed understanding of pelvic anatomy.

Surgical repair of the vulva or vagina following trauma should be undertaken to obtain control of hemorrhage or to restore structural and functional integrity of lower genital tract structures.

The surface anatomy of the perineum and vulva is shown in the image below. Pertinent features are labeled. Surface features serve as useful landmarks for important deep structures. For example, the lateral segments of the hymeneal ring overlie the medial borders of the levator ani muscles. The labia majora are elevated by the bulbocavernosus muscles and vestibular bulbs. Surrounding the anus are radially directed superficial skin folds created by subcutaneous attachments of the extrinsic anal sphincter fibers. In the nulliparous female, the sagittal dimension of both the vaginal introitus and the perineum is approximately 2 cm. An increase introitus:perineum ration may indicate perineal body disruption, especially in the nulliparous patient.

The following image illustrates pertinent vulvar structures deep to the skin.

Take special note of the following features:

The perineum can be conveniently conceptualized as being composed of anterior and posterior triangles divided by a line connecting the 2 ischial tuberosities. Posterior to this line, which parallels the posterior borders of the transverse perineal muscles, are the ischiorectal fossae, which are fatty, tissue-filled spaces that communicate with the subcutaneous fat-pad of the back. Anterior to this line is the perineal membrane.[4] This layer, which is pierced by the genital hiatus and the urethra, separates the anterior triangles into deep and superficial compartments.

On either side of the vaginal vestibule, immediately under the skin of the labium major, is a fingerlike extension of the superficial fatty layer (Camper fascia) of the lower abdominal wall. Through the medial aspect of this process passes a projection of the round ligament, which is surrounded by extensions of layers of the abdominal aponeurosis as it emerges from the external inguinal ring. Terminal processes of the round ligament insert in the fibers of the bulbocavernosus muscles.

The superficial anterior perineal compartment lies under the perineal fat pad on either side of the vaginal hiatus. This triangular compartment is bounded (1) medially by the bulbocavernosus (bulbospongiosus) muscles, which border the vaginal introitus; (2) laterally by the ischiocavernosus muscles, which lie along the ischiopubic rami; and (3) dorsally by transverse fibromuscular structures (the transverse perineal muscles), which span the gap between the ischial tuberosity and the central tendon of the perineum.

The anterior surface of the compartment is composed of condensation of areolar and adipose tissue, (ie, Colles fascia). This layer, which is a continuation of the Scarpa fascia of the anterior abdominal wall, extends from the lateral aspect of the bulbocavernosus muscle to the ischiopubic ramus. Anteriorly it inserts in the connective tissue of the inguinal ligament, and posteriorly it terminates as the fascia of the posterior margin of the anterior perineal triangle. The deep surface of the compartment is the perineal membrane.

The bulbocavernosus muscles originate at the deep surface of the inferior margin of the pubic arch, then course posteriorly along the lateral surfaces of the vaginal introitus to insert in the central tendon of the perineum (perineal body) between the posterior vaginal fourchette and the anus. Contraction of these muscles serves to close the distal portion of the vaginal hiatus.[5] Each of these muscles overlies one of the paired vestibular bulbs, which are composed of highly vascular erectile tissue and venous plexus enmeshed in loose connective tissue. The vestibular bulbs become engorged during sexual arousal.

Midline perineal structures important to this topic include the clitoris, urethra, vagina, central tendon of the perineum, anal canal, and anal sphincter complex.[6]

The urethral meatus penetrates the perineal membrane (urogenital diaphragm) immediately anterior to the vagina. At this level, the perineal membrane, compressor urethrae, and urethrovaginal sphincter muscle of the distal urethra intermingle to form a dense 3-diminsional mass of tissue.[7] Anterior to the urethral meatus is the clitoris, which is suspended from the inferior arch of the pubic body by a suspensory ligament through which passes the clitoral vasculature.

The vagina is a hollow, muscle-walled viscous organ lined by nonkeratinizing squamous epithelium. Distal to the hymeneal ring, the vagina opens into the vestibule, which is bordered by the paired labia minora. The distal third of the vagina is densely adherent to the perineal membrane anteriorly and laterally, the medial borders of the levator ani laterally, and the perineal body posteriorly.

Above the levator ani, the muscular tube of the vagina is encased in loose connective tissue. The vagina is suspended in its position by the attachment of lateral condensations of this connective tissue (the paracolpos or fibers of Luschka) to the internal fascia of the levator ani and obturator internus muscles. Apical support of the vagina, together with the cervix and uterus, is provided by the cardinal and uterosacral ligaments.

The cardinal ligaments consist of condensations of loose areolar tissue, nerves, and blood vessels. These bundles sweep from the anterolateral aspects of the proximal anterior vagina and cervix to invest in the fascia of the ipsilateral coccygeus muscle proximal and medial to the ischial spines.

The uterosacral ligaments are similar complexes extending from the cervix and proximal posterior vaginal wall to invest along the lateral surfaces of the bodies of the second through fourth sacral vertebrae.

At the level of the perineal diaphragm, the urethra is so intimately related to the distal vagina that there is no natural cleavage plane between the two. Proximal to the levator fascia, the previously described vaginal adventitia separates the urethra and bladder from the vaginal muscularis.

 

Immediately posterior to the vaginal vestibule is the perineal body. From a functional standpoint, referring to the connective tissue elements of this structure as the central tendon of the perineum is more appropriate. Into this structure is inserted the paired bulbocavernosus muscles described above, the paired transverse perineal muscles, which originate at the ischial tuberosities, and fibers from the external anal sphincter. Into the deep portion of the perineal body, the fibers of the levator raphe and the rectovaginal fascia are inserted.[8] This relationship is discussed in more detail later.

The importance of the central tendon of the perineum is evident from evaluation of the distribution and orientation of the fibers of the contributing muscle groups. If the perineal body is intact, coordinated contraction of these muscles, including the anal sphincter, results in cephalad motion of the central tendon and, consequently, elevation of the perineum.

 

Posterior to the perineal body is the anal canal. This, the terminus of the gastrointestinal tract, is composed of the same tissue layers as the more proximal components, ie, mucosa and submucosa surrounded by a lamina propria, an internal, circularly oriented smooth muscle layer, and an external longitudinal smooth muscle layer. The thickened circular smooth muscle layer of the proximal anal canal forms the internal anal sphincter, which provides 75-85% of the resting tone of the anal wall.

Caudad to the levator ani, the striated muscle fibers of the external anal sphincter surround the anal canal. This muscle is typically thought of as being composed of 3 components: the distal (subcutaneous) segment, the intermediate segment, and the proximal (deep) segment. The superficial segment is attached posteriorly to the tip of the coccyx, whereas the deep segment is intimately related to the puborectalis fibers that sweep posterior to the anal canal.

Anteriorly, fibers from the external sphincter insert into the central tendon of the perineum. The anal sphincter complex, composed of both internal and external anal sphincter components, averages almost 2 cm in thickness and extends for a distance of almost 3 cm caudad to the levator border. The internal anal sphincter, composed of smooth muscle, is innervated by the intrinsic autonomic system of the gastrointestinal system. The external anal sphincter receives innervation from the pudendal nerve.

Above the puborectalis raphe, the vagina is separated from the underlying distal rectum by a thin layer of connective tissue, the rectovaginal fascia or fascia of Denonvilliers, which is generally rudimentary in the female. Each lateral border of this sheet of tissue is fused with the inner fascia of the ipsilateral levator ani complex. This tissue sheet overlies the rectum, spanning the posterior pelvis from the level of the ischial spines distally to the levator raphe, into which it inserts.

Note that the most inferior recess of the peritoneal cavity (pouch of Douglas) is adjacent to that portion of the proximal posterior vaginal wall between the rectosigmoid junction and the posterior lip of the cervix.

Deep to the perineal membrane anteriorly, and forming the deep margin of the posterior compartment, are the levator ani muscles. These striated muscle groups originate along the posterior aspect of the pubic bone and the inferior margin of the obturator muscles (ie, arcus tendentious levator ani), and sweep posteriorly and medially to insert into the levator plate, a band of connective tissue extending from the coccyx to the posterior aspect of the rectum as it passes through the levator hiatus.

Fibers of the most medial of these bundles are intertwined with the deep portion of the perineal body between the vagina and the anal canal. The distal margin of the rectovaginal fascia is also fused with this complex. This layer of connective tissue, which separates the muscular walls of the vagina from the distal rectum, inserts into the anterior fascia of the levator ani on either side of the pelvis, along a line that extends from the ischial spine distally to the central perineal tendon between the anal canal and the vaginal fourchette.

The image below illustrates the vascular supply of the perineum.

The principal arterial supply to the perineum are the internal pudendal arteries. Each of these terminal branches of the internal iliac arteries passes medial to its ipsilateral ischial spine, then divides into a medially directed branch to the distal rectum (the inferior hemorrhoidal arteries) and a branch that courses anteromedially along the ischiopubic ramus to the pubic arch. Superficial and deep tributaries of this branch, in turn, course medially to supply the superficial structures, the central tendon of the perineum, the vestibular bulb, the distal urethra, and the clitoris. As is generally true of the pelvic region, there is an extensive anastomotic network of this vasculature with superficial branches of the ipsilateral femoral artery, most notably the external pudendal artery.

Arterial supply to the proximal vagina derives from several sources. Tributaries from the internal pudendal artery enter the superior aspect of the vagina via the uterosacral ligaments, then divide into lateral and medial branches along the posterior aspect of the vagina. Branches of the internal iliac and uterine arteries supply the anterior and anterolateral aspects of the vagina via the cardinal ligaments.

Innervation of the deep pelvis is provided by branches of the pudendal nerve. The superficial perineum derives sensory innervation primarily from the genital-femoral and ilioinguinal nerves, which originate in the upper lumbar portion of the spinal cord and pass through the inguinal canal to reach the perineum. The lateral femoral cutaneous and iliohypogastric nerves also provide sensory information.[9]

For more information about the relevant anatomy, see Vaginal Anatomy and Female Reproductive Organ Anatomy.

Do not undertake restorative surgical management of a patient who has sustained perineal trauma, except as necessary to achieve control of hemorrhage, until the patient is sufficiently stable to tolerate general or regional anesthesia.

In general, assessment of vulvovaginal trauma does not require extensive laboratory testing.

Hemoglobin and hematocrit: If the injury is associated with significant overt hemorrhage (eg, as during parturition) or if extensive occult bleeding is suspected, hemoglobin and hematocrit levels may be significantly decreased. These values take time to equilibrate following acute blood loss, so the acute values may not reflect ultimate levels.

Urinalysis: Should deep organ injury be suspected, a urinalysis should be obtained to determine whether the patient has developed hematuria.

Sexually transmitted disease screening: A woman who has been the victim of sexual assault should be tested for sexually transmitted diseases (STDs), including serologic testing for syphilis. Recombinant hybridization techniques are available to permit evaluation for gonorrhea and chlamydia. She should also be offered the option of testing for exposure to HIV.[10]

Packed red blood cells: Used in patients found to be or are at risk of becoming hemodynamically unstable.

The decision to obtain imaging studies, as well as the specific studies chosen, should be guided by the nature of the injury, as indicated by history and physical examination findings. Further evaluation is certainly indicated if lower urinary tract (eg, urethral, bladder, ureteral) injury or occult hemorrhage is suspected. Severe perineal trauma may raise the question of skeletal damage, which should be evaluated appropriately.

Transvaginal ultrasonography: If the patient is able to tolerate it, transvaginal ultrasonography is the most specific imaging study to detect free fluid in the pelvis and abnormalities of the internal genitalia. A transabdominal study is a second choice.

Abdominal plain film radiography: If preliminary evaluation of vaginal trauma raises the possibility of intraperitoneal extension, addressing this concern definitively is important. The presence of free air in the peritoneal cavity can result either from penetrating injury to the proximal posterior vaginal wall, which extends through the peritoneum, or from gastrointestinal perforation. A radiograph of the patient's abdomen while she is erect or, alternatively, a lateral radiograph while she is lying on her side, reveals the presence of free air under the superior aspect of the peritoneal cavity (eg, the diaphragm in the case of an upright radiograph).

A note of caution: In the setting of perineal or vaginal trauma, should intraperitoneal pathology be suspected, imaging may prove helpful. The objective of such an evaluation is not to construct a detailed analysis of the intraperitoneal anatomy, but rather to rapidly determine the presence of intraperitoneal free air or fluid. Such findings, especially in the setting of hemodynamic instablity, should prompt a decision for operative exploration.

If disruption of the bony pelvis is suspected, a CT scan of the pelvis and lower abdomen can provide detailed information regarding not only the skeletal integrity, but also the existence of large retroperitoneal fluid collections such as hematomata. Use of intravenous contrast material during such a study, provided the patient is not sensitive to the contrast, adds additional information regarding the integrity and position of the ureters.

Voiding cystourethrography: Urethral injury can usually be detected during physical examination. The finding of urethral trauma should prompt further evaluation of possible bladder insult. One very useful imaging study in this situation is the voiding cystourethrogram, in which contrast fluid is instilled into the bladder via transurethral catheter. Subsequent lateral and anteroposterior images allow for excellent visualization of the bladder lumen. Fluoroscopic images of the urethra during subsequent voiding provide further information regarding urethral integrity.

Transurethral cystoscopy: Another option for lower urinary tract evaluation is transurethral cystoscopy, which permits direct visualization of the urethral and bladder lumen, urethrovesical junction, and ureteral orifices.

Retrograde urograms: Performed under fluoroscopic guidance, these provide information regarding ureteral integrity. This alternative is especially appropriate if the patient otherwise requires anesthesia for evaluation or therapy.

 

 

Management of a patient who has sustained perineal trauma must address the following objectives:

• Minimization of blood loss
• Minimization of risk for infection
• Detection and correction of injury to pelvic organs and support structures
• Restoration of function
• Relief of pain

Cosmetic restoration, while an important goal, must be considered a secondary objective.

 

The following discussion is limited to management of perineal, vulvar, and vaginal injuries. As noted previously, the possibility of intraperitoneal pathology must be considered. If present, such pathology must be corrected; however, such a discussion is beyond the scope of this article.

Ensure that tetanus prophylaxis is current. 

Superficial perineal trauma, in the absence of significant bleeding, generally resolves with conservative management. Address injuries associated with hemorrhage or disruption of deep structures with surgery. In the case of soft tissue trauma, palliative therapy, such as ice packs applied to the site for the first 24 hours, is useful.

Should operative reconstruction be indicated, site preparation, adequate anesthesia, and unfettered access to the surgical field are of paramount importance. Note the following considerations:

• Positioning: For most procedures involving the female perineum, the dorsal lithotomy position, with legs abducted and slightly hyperextended, is preferable. Take care to avoid applying undue pressure against the soft tissues of the upper legs or lower abdomen in order to prevent subsequent neuropathy.

• Site of surgery: Except for superficial lacerations, surgical therapy for most perineal trauma is of sufficient complexity that an operating room with sufficient light, technical assistance, and equipment is recommended.

• Anesthesia: For superficial lacerations of the vulva, local anesthesia may be sufficient. However, if extensive dissection, prolonged operating time, or manipulation of normally tender tissues is anticipated, administration of regional or general anesthesia is warranted. Maintain a very low threshold for regional or general anesthesia for pediatric patients.

• Preoperative medications: Consider antibiotic prophylaxis, especially in the case of a patient with trauma involving the urinary tract. A first- or second-generation cephalosporin administered in the preoperative holding area is appropriate. In patients at elevated risk for thromboembolic phenomena, perioperative antithrombosis prophylaxis is advisable.

• Site preparation: Standard surgical preparation should be performed on the operative site.

Intraoperative details depend on the location of the injury.

Straddle injury - perineum

This injury results from blunt impact trauma to the perineum. The classic example is that of a young child who falls straddling a bar of a jungle gym. The impact results in such rapid distention of the perineal epithelium that the elastic limit is exceeded and the epithelium tears. Commonly, only superficial tissues are involved. Examine the perineum, proximal vagina, and anus to ensure that deeper structures are not involved. Examination under anesthesia may be appropriate for very young children in order to avoid additional psychological trauma.[11, 12]

If only superficial epithelium is involved and bleeding is minimal, thorough cleansing and oral analgesia are often all that is required because the forces acting on the perineal skin keep the edges of such lacerations apposed. If bleeding is a concern, 1 or 2 simple subcutaneous sutures of fine delayed absorbable braided suture are generally sufficient.

The patient should be observed for perineal hematoma formation. As noted, the perineal tissues are quite elastic and provide minimal resistance to hematoma expansion. Nonetheless, as most vulvar hematomata are of venous origin, conservative management with rest, external pressure, and ice packs is usually sufficient. Should serial observation reveal continued expansion of the hematoma despite such measures, or if the patient develops hemodynamic instability, surgical management should be instituted. This would involve incision and drainage of the hematoma and exploration of the cavity to identify a bleeding arterial source. Care should be taken to minimize further venous trauma, especially in the area of the vestibular bulb. Antibiotic prophylaxis should be considered.[3]

Following initial therapy, advise the patient to avoid activities involving abduction of the thighs for several days. 

Deep perineal laceration - perineum

This section is devoted to management of deep perineal lacerations. Management of other vaginal sites is discussed in other sections.

Repair of perineal trauma in the non-pregnant patient is very similar to that required for a parturient who has sustained obstetrical trauma. As noted in the discussion of perineal anatomy, the perineum is richly perfused. The venous network, both because of the absence of valves to reduce backflow from the proximal system, and (in the case of the post-partum patient) of increased pressure during the second stage of labor, can undergo extensive distention. Laceration of the perineum can thus be associated with impressive blood loss.

Achieving temporary hemostasis must therefore be a principal initial objective. Fortunately, venous bleeding generally is easily controlled with appropriately applied pressure. One simple, rapid, and minimally uncomfortable technique is to grasp the region around the bleeding vessel with a ring forceps, which is then closed only to the first ratchet setting. This provides an opportunity to conduct a complete assessment of the extent of damage.

In an attempt to minimize repetition, the remainder of this discussion describes a single effective technique for repair of a complete perineal laceration (one that extends cephalad of the hymen and the anal verge, disrupting the entire perineal body and anal sphincter complex). The principles discussed are also generally applicable to less extensive tissue disruption. Note that the intent of the following description is to illustrate only one of several methods of achieving the goals of repair, especially the ultimate objective of restoring tissue integrity and function.

Remember that repair of a perineal laceration, especially an extensive one, is a true surgical endeavor. Generally accepted surgical principles are thus very much in order. Essential to a successful outcome are appropriate surgical setting, sufficient lighting, appropriate assistance, and adequate anesthesia. Unfortunately, in many instances, these requirements are not met, increasing the risk of poor results.

The steps involved in this procedure are the same as for any surgical procedure: to identify, restore, and repair anatomy. Meticulous attention to hemostasis is essential, and every attempt should be made to minimize tension. Techniques relying on bulk closure of a perineal defect are inferior to site-specific methods in which care is taken to restore the original anatomic tissue relationships. This observation is especially true of postmenopausal women, in whom the perineum is less resilient.

The initial step in the repair is identification of the proximal extent of both vaginal epithelial and rectal epithelial laceration. Unfortunately, although rectal lacerations are usually linear, vaginal tears are frequently branched, often extending along both posterolateral gutters. In addition to the anterior and posterior apices, identifying the medial ends of the posterior portion of the hymeneal ring is useful. These surface features, as discussed previously, overlie the medial borders of the levator ani muscles.

Once the extent of the laceration has been determined, the repair proceeds in a stepwise fashion, as follows:

1. Repair of the rectal mucosa and submucosa

2. Repair of internal and external anal sphincter

3. Repair of the rectovaginal fascia and proximal perineal body

4. Repair of the vaginal epithelium and subepithelial tissue

5. Repair of the distal perineal body

6. Repair of the epithelium of the perineum and fourchette

Repair of the rectal mucosa and submucosa is best accomplished in 2 layers to satisfy the objective of minimizing tension across the wound. One means of achieving a watertight epithelial closure is to place an initial submucosal running course of fine delayed absorbable braided suture, reinforced with a second imbricating layer closed with simple interrupted sutures of the same suture. Successful anatomic reconstruction requires good delineation of the anal canal, which is best accomplished by placing the middle finger of the nondominant hand in the anal canal and advancing the fingertip above the superior apex of the anal mucosa laceration. It is important to ensure that the most superior loop of the first suture layer is proximal to the upper apex of the laceration to minimize nonunion of the epithelium and subsequent rectovaginal fistula formation. The internal layer extends from the apex to the level of the anal verge.  The imbricating layer extends from the apex to the levator borders. This technique effectively reapposes the rectovaginal fascia to the superior aspect of the puborectalis raphe, reconstituting the proximal aspect of the perineal body.

The next step is repair of the internal and external sphincter. As noted in the discussion of perineal anatomy, the internal anal sphincter is a physiologic thickening of the circular muscle layer of the distal rectum and proximal anus, extending approximately 3 cm along the anal axis. The external anal sphincter overlaps (for approximately 1.5 cm) the distal internal anal sphincter. Restoration of these relationships improves the probability of restored function.

 The internal sphincter is smooth muscle, which has no fascia capsule. However, this layer is surrounded by the structures of the perineal body, which are partially comprised of connective tissue. Using the finger as a guide, it is possible to reapproximate the internal sphincter layer, together with surrounding connective tissue, anterior to the anal canal with a series of moderate-gauge (eg, 2-0) delayed absorbable polyfilament sutures from the upper extent of the rectal laceration distally to the capsule of the external anal sphincter.

Although end-to-end reapproximation of the external anal sphincter capsule is the technique typically described in obstetric and gynecology textbooks, this closure method is associated with a lower long-term success rate than the overlapping closure technique favored in the colorectal surgery literature.[13] In the latter method, a far-near/near-far, full-thickness suture placement scheme is used from the superior aspect of the external sphincter to its inferior border, thereby overlapping the separated ends of the disrupted sphincter and its capsule. Generally, placing as many as 4 such sutures in the sphincter is possible. Note that the external sphincter, by its nature, is under tension. Given this constraint, using multiple simple loops of larger caliber absorbable suture for this aspect of the repair to permit sufficient time for tissue healing is prudent.

Repair of the vaginal epithelium and subepithelial tissues is next. The vaginal epithelium is generally very resilient, and heals rapidly; therefore, this portion of the procedure can be accomplished successfully with a single-layer closure. Specific attention to the paired midline arterial supply of the posterior vaginal wall is prudent. The initial pass of the needle must be superior to the apex of the laceration in order to achieve hemostasis of these arteries. Care must also be taken to avoid incorporating the rectal mucosa into this vaginal suture. As noted previously, the medial ends of the disrupted hymen serve as the inferior landmarks for this portion of the procedure. This layer can be closed effectively with a single, running, moderate-gauge, polyfilament delayed absorbable suture that incorporates both the epithelial and subepithelial tissues from the initial pass distally to the hymeneal ring. 

At this juncture, it is convenient to continue this layer as a running subcuticular closure from the level of the puborectalis raphe, as marked by the hymeneal ring, out to the distal end of the fourchette, thereby closing the epithelium of the fourchette.

Accomplish repair of the distal perineal body in layers with simple interrupted sutures of moderate-gauge delayed absorbable suture.

For repair of the perineal epithelium, the suture penetration of the skin increases postprocedure pain. As noted earlier, adduction of the legs results in compression of the perineum, enhancing closure. A running subcutaneous suture of fine delayed absorbable polyfilament suture is therefore appropriate for this layer.

Ensure good hemostasis at each step of this repair.

Blunt trauma or foreign body injury - urethra

Lacerations of the tissues surrounding the external urethral meatus are generally limited to epithelium or superficial subepithelial tissue. This is also true of shallow lacerations of the distal urethra itself. In the absence of bleeding, adequate healing can occur with only conservative management. If a superficial bleeding source does not respond to brief pressure, 1 or 2 simple sutures of fine delayed absorbable suture generally suffice. Management of lacerations extending deeper into the urethral canal or penetrating into the urogenital diaphragm is discussed below.

Penetrating injury - urethra

As discussed previously, support of the distal urethra is provided by the relatively dense and nondistendible tissue of the urogenital diaphragm. Significant shear force is required to disrupt this tissue layer. The urethral wall, on the other hand, has much less strength, so that injuries resulting in disruption of the urogenital diaphragm frequently also involve the full thickness of the adjacent urethral wall.[14] If such an injury is detected, complete evaluation of the urethra and bladder, as discussed in the section on evaluation, is appropriate.

Repair of injuries of the distal urethral and urogenital urethral supports is accomplished by a layered approach. After the proximal urethra and bladder have been evaluated, the vaginal epithelium is carefully and sharply dissected off the underlying tissue to mobilize the lacerated tissue. The urethral mucosa is closed with a running suture of fine delayed absorbable polyfilament suture. A second imbricating layer of interrupted fine delayed absorbable polyfilament sutures is placed to reapproximate the submucosal layer. Another layer of simple interrupted sutures of the same material is then placed to repair the tissues of the perineal diaphragm. The epithelium can be closed with simple interrupted subcutaneous sutures.

Foreign body penetrating injury - vagina

Any patient who has sustained foreign body penetrating injury of the proximal vagina must be evaluated for associated broad ligament and intraperitoneal damage, as described earlier. Once these possibilities have been reliably excluded, planning the surgical approach to repair must include consideration of the close approximation of the ureters to the anterolateral vaginal fornices. If damage to the vaginal epithelium is detected in this vicinity, undertake measures to evaluate the possibility of ureteral compromise and consider the option of cystoscopic placement of ureteral stents to minimize the risk of ureteral incorporation into the repair.

When closing a vaginal wall laceration, remember that the blood vessels of the vagina are located between the outer muscular layer of the vaginal wall and the surrounding loose connective tissue; therefore, ensure that the full thickness of the vaginal wall, including the connective tissue layer, is incorporated in the closure sutures in order to obtain hemostasis. Also, remember that the layer between the lateral aspect of the super-levator vagina and the levator ani is a potential space, easily distended by an expanding hematoma. If hemostasis is questionable following vaginal wall repair, consider placement of a closed suction drain in the paravaginal space.

Distention laceration - proximal vagina (including obstetric injury)

For treatment of a lateral fornix (sulcus tear), see the earlier discussion regarding repair of penetrating injuries to the vagina.

For posterolateral tears, when closing a vaginal wall laceration, remember that the blood vessels of the vagina are located between the outer muscular layer of the vaginal wall and the surrounding loose connective tissue. Therefore, ensure that the full thickness of the vaginal wall, including the connective tissue layer, is incorporated in the closure sutures to obtain hemostasis. Remember that the separation between the lateral aspect of the vagina and the levator ani is a potential space, easily distended by an expanding hematoma. If hemostasis is questionable following vaginal wall repair, consider placement of a closed suction drain in the paravaginal space.

A 2016 ACOG Practice Bulletin on the Prevention and Management of Obstetric Lacerations at Vaginal Delivery estimated that 53% to 79% of women will experience some type of laceration during vaginal delivery, most commonly in the perineal body, however most lacerations do not result in adverse functional outcomes. The bulletin also stated that the more severe third- and fourth-degree lacerations that result in obstetric anal sphincter injuries (OASIS) may occur in up to 11% of women giving birth vaginally. The bulletin recommended that perineal massage, either antepartum or during the second stage of labor, can decrease muscular resistance and reduce the likelihood of laceration and the use of warm compresses on the perineum during pushing can reduce third-degree and fourth-degree lacerations.[15, 16]

Hematoma - vulva

As noted in the discussion of pelvic anatomy, the superficial compartment of the anterior perineal triangle communicates with the subfascial space of the lower abdomen below the inguinal ligament. Little tissue is available to tamponade bleeding into this space, even from the low-pressure venous system; thus, a hematoma can extend from the posterior margin of the anterior triangle (at the level of the transverse perineal muscle), anteriorly over the mons to the fusion of fascia at the inguinal ligament.

A hematoma resulting from venous bleeding, although it can form rapidly, stabilizes at the above margins because of the low-pressure nature of the bleeding, and therefore may be managed expectantly. On the other hand, a rapidly expanding hematoma that does not stabilize is more likely to be the result of arterial bleeding. In such an instance, an incision medial to the labium majus permits evacuation of the hematoma. If possible, identify and ligate the source of bleeding.

Laceration - vulva

A superficial laceration of the vulva can be managed in a fashion similar to any other skin laceration. If the laceration extends into the superficial triangle and involves the vestibular bulb, it can be associated with significant blood loss. As noted previously, blood supply to this region is derived from both lateral and medial sources. Additionally, the tissue involved is erectile tissue, which is quite friable. Hemostasis in this region is best achieved by wide lateral and medial sutures that incorporate both the superficial and deep fascial borders of the space, thereby sandwiching the erectile tissue between 2 dense connective tissue layers.

Appropriate post-operative analgesia is important to minimize inhibition of patient ambulation. A multi-agent regimen is preferred. Narcotic therapy should be kept to a minimum to avoid constipation. Stool softeners and increased oral fluids should be considered. Ice packs to the perineum for the first 24 hours are useful analgesia supplements.

Meticulous perineal hygiene is essential to minimize infection. Sitz baths in clear warm water two or three times/day are useful adjunctive therapy. Although preoperative antibiotic prophylaxis may, in selected instances, be considered, continuing such measures postoperatively in the absence of overt preexisting infection is of no value.

Adequate bladder drainage must be confirmed. Vulvar trauma can result in periurethral soft tissue edema or pain sufficient to prohibit normal micturition. Although indwelling transurethral catheters are associated with increased risk of urinary tract infections, urinary obstruction or urethral surgery may require indwelling transurethral or suprapubic bladder drainage.

Question all patients who sustain nonobstetric perineal trauma about the status of tetanus immunization.

Maintain appropriate anti-thrombotic measures.

 

Patients who require significant surgical therapy for perineal trauma are at significant risk for infection. Encourage the patient to maintain good hygiene of the area. This can be problematic, given the discomfort that commonly accompanies perineal trauma and its repair.

Instruct the patient regarding early signs of infection, and see her often enough in the immediate postoperative period to ensure early detection of incipient infection.

Encourage the patient to increase progressively her level of ambulation and resumption of normal activites. Prolonged sitting or standing should be avoided. Advise against sexual activity until healing is completed. 

Patients who require surgical therapy for perineal trauma are at risk of complications from both the trauma and its management.

Infection, as noted earlier, must be watched for closely. The patient must be instructed regarding signs of early infection and must be monitored often enough during the immediate postoperative period to permit early identification.

Repair dehiscence

Patients with traumatized tissues have suffered, to a greater or lesser extent, devascularization and initiation of tissue necrosis and are at risk of postrepair wound disruption. This is especially true of patients whose tissues were repaired under tension.

Cosmesis

Other sequelae of tissue trauma, devascularization, and necrosis are poor tissue healing and scar retraction, which may result in altered cosmetic appearance. At some point early in the management process, the patient should be counseled regarding this possibility in order to minimize disappointment and recriminations.

Abscesses

Abscesses involving the greater vestibular gland complex result from occlusion of the common duct draining the complex, not the actual glands. Recurrent abscess formation occurs when previous drainage attempts have failed to establish a patent meatus and warrant more aggressive measures to disrupt internal loculations and to create a satisfactory sinus tract. The glands are embedded in the vascular complex of the vestibular bulb. Excision can be associated with significant bleeding because this tissue obtains its blood supply from both lateral and medial sources.

Pain

Chronic pain is not uncommon following perineal trauma, especially that of nonobstetric etiology. Adequate perioperative analgesia is of great importance.

Long-term counseling should be offered, especially for patients who have been victims of sexual assault.

In the absence of early infection and wound breakdown, perineal trauma generally responds favorably to surgical therapy. Posttraumatic chronic pain is possible.

Two sites are at increased risk of long-term functional deficit: the urethra and the rectal sphincter. A progressive decrement in function of both of these structures occurs with aging. Many women experience additional decrement associated with sphincter repair, especially of the external anal sphincter, even following appropriate vulvar reconstruction.

As noted, the ultimate cosmetic result following acute management of perineal trauma may be suboptimal. Plastic revision may be considered after completion of the healing process but generally should be delayed 3-6 months.