Third degree perineal lacerations-How, why and when? A review analysis

doi:10.4236/ojog.2012.23064

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Open Journal of Obstetrics and Gynecology, 2012, 2, 304-310 OJOG

http://dx.doi.org/10.4236/ojog.2012.23064 Published Online September 2012 (http://www.SciRP.org/journal/ojog/)

Third degree perineal lacerations—How, why and when?

A review analysis

Angelos Daniilidis1, Vasilis Markis1, Menelaos Tzafetas1, Panagiotis Loufopoulos1, Pan agiotis Hatz is 1,

Nikolaos Vrachnis2, Konstantinos Dinas1

1Department of Obstetrics and Gynecology, Hippokratio General Hospital, Aristotle University of Thessaloniki, T hessaloniki, Gre ece

2Department of Ob s tetrics and Gynaec ology, Ateraieio Hospital, Athens, Greece

Email: [email protected]

Received 28 March 2012; revised 30 April 2012; accepted 13 May 2012

ABSTRACT

Aim: The aim of this article is to present the know-

ledge of current literature regarding epidemiology

and predisposing factors, classification and surgical

treatment of third degree perineal tears. Materials

and Methods: We reviewed current articles in Eng-

lish language from medline and Pub-Med using as

key words “vaginal repair, third degree tear, episi-

otomy and vaginal delivery”. We summarized litera-

ture regarding predisposing factors, epidemiology,

prevention and surgical treatment of third degree

perineal tears. Results: it is demonstrated today by

several studies that widespread episiotomy is respon-

sible for the increasing frequency of 3rd degree la-

cerations of the perineum which are significantly as-

sociated with forceps and the use of gynecological

chair (boom) for vaginal delivery. Primipa rou s wo m e n

with babies weighting > 4 kgr, are at greater risk.

Two types of surgical repair: end-to-end approxima-

tion and overlapping of torn ends of the anal sphinc-

ter, are both related to the functional outcome of the

repair. Conclusion: Episiotomy is an important risk

factor for severe lacerations after vaginal delivery.

Midline episiotomy and assisted vaginal delivery should

be avoided whenever possible, especially in the pre-

sence of a large baby. Recent evidence suggests that

there is no significant advantage between overlap re-

pair and approximation technique, with regard to

fecal incontinence.

Keywords: Vaginal Repair; Third Degree Tear;

Episiotomy; Vaginal Delivery

1. INTRODUCTION

Third degree perineal lacerations are known since the

time of Hippocrates. They involve a tear in the vagina,

skin, muscles between the vagina and anus (perineal skin

& perineal muscles) and anal sphincter. Directly under-

neath the layer of squamous epithelium and vaginal mu-

cosa lies the perineal body which is triangular in shape

and is the join connection between bulbospongiosus,

superficial transverse perineal and anal sphincter muscles.

The anal sphincter consists of two separate muscles: the

internal and the external anal sphincter. A tear can be

through one or both of these muscle s (Figure 1).

The classification system establishes a framework for

evaluation, discussion of the degree of injury, appropriate

treatment and rehabilitation research. In the USA, a clas-

sification system of four levels is used, in contract to a

three level system used in Europe (Europe’s third level

corresponds to the fourth level of America) (Table 1).

Perineal tears occur more frequently in the presence of

median episiotomy or in operative vaginal deliveries. In

developed countries the incidence of third-degree peri-

neal tears ranges between 0.5% and 1% of all vaginal de-

liveries [1]. Proper assessment and rehabilitation is neces-

sary to prevent complications. The degree of laceration is

Figure 1. Third degree lacer ation.

OPEN ACCESS

A. Daniilidis et al. / Open Journal of Obstetrics and Gynecology 2 (2012) 304-310 305

Table 1. Classification of perineal tears.

Degree of laceration

First degree Superficial laceration of the vaginal mucosa or perineal body.

Second degree Laceration of the vaginal mucosa and/or perineal skin and deeper subcutaneous tissues.

Third degree incomplete Second degree laceration with la ce ration of the capsule and pa rt (but not all) of the a n a l sp h i n c t er muscle.

Third degree complete As above with comple t e laceration of the anal sphincter muscle.

Fourth degree Complete third degree laceration with laceration of the rectal mucosa.

graded and determines the method of repair, the tech-

nique of which has changed little over the past 50 years.

Episiotomy is the overriding determinant of third-degree

lacerations [2].

The aim of this article is to review the current litera-

ture regarding epidemiology, predisposing factors, clas-

sification and surgical treatment of third degree perineal

tears.

1.1. Predisposing

Factors-Epidemiology-Prevention

The first proposal for episiotomy was made by Ould in

1742 to facilitate the 2nd stage of labour. It was not until

1920 when Delle and Pomeroy publish ed several articles

suggesting that the wide use of routine episiotomy to

primiparous women, provide protection from the 3rd de-

gree perineal lacerations. In 1948 the Kaltreider and

Dixon [3] noted the high incidence of rectal lacerations

with median episiotomy and created the question of the

effectiveness in practice [3]. The widespread episiotomy

today is demonstrated through studies to be responsible

for the increasing frequency of 3rd degree lacerations.

The medio-lateral episiotomy seems to have an advan-

tage in comparison to median episiotomy. The trend is

that it should be used only when necessary [1,3-5]. A

conservative approach to the use of mediolateral episi-

otomy consists a reasonable solution in order to prevent

third-degree lacerations [6]. Reduction in episiotomy

results in less posterior perineal trauma, less aggregation

and fewer complications, but there is no difference in the

degree of pain and severe vaginal and perineal trauma.

On the contrary there seems to be an increased risk of

anterior wall trauma.

The use of gynecological chair (boom) for vaginal de-

livery, increases the risk of third degree perineal tears.

In cases of spontaneous births the use of episiotomy is

limited to 1 in 5 spontaneous deliveries There is a sig-

nificant association between third degree perineal lacera-

tions and the use of forceps [1,6]. Evidence shows that in

operative delivery methods, vacuum extractor has an

advantage over the use of metallic forceps regarding the

risk for third degree tears. The same applies for the pre-

vention of faecal incontin ence [7,8]. Following this com-

plication about 44% of the patients remain symptomatic

[8].

Third-degree tears are significantly more common in

primigravidae and mothers with high birth-weight babies

[9]. Primiparous women who have delivered babies with

weight > 4 kgr, have a greater risk for third degree per-

ineal lacerations. There are also reports and studies ac-

cording to which multiparous women following opera-

tive delivery and episiotomy are at increased risk com-

pared to wom e n wh o del i ver spontane o usl y (Table 2).

Gestational age, marital status, weight before preg-

nancy, weight gain during pregnancy, height, education,

labour or physical condition are factors which don’t seem

to be associated with this type of injuries. Factors that

could increase perineal integrity are: spontaneous or va-

cuum assisted delivery, rather than forceps, also avoiding

episiotomy, allowing time for perineal thinning and per-

ineal massage during the weeks before childbirth in nul-

liparous women.

Before treatment we have to focus on contradictory

preventive strategies. It might seem that restrictive episi-

otomy has been shown to result in less posterior perineal

trauma, less suturing and fewer complications, but there

is no difference for severe vaginal or anterior wall

trauma [1,3,5].

1.2. Surgical Techniques for Repairing Third

Degree Perineal Tear

A cooperative patient is of very high importance for good

exposure and adequate repair. Anesthesia should be al-

ways used and epidural anesthesia is considered to be the

Table 2. Risk factors associated with third-degree

perineal tears [1].

Routine episiotomy (midline > mediolatera l)

Delivery with stirrups (delivery table, lithotomy)

Operative delivery (metal forceps > vacuum extractor)

Experience of delivering provider

Prolonged second stage of labor

Nulliparity

Occipital posterior or occipital transverse position

Anesthesia (local or epidural)

Age of pregnant women (less than 21 years)

Use of oxytocin

A. Daniilidis et al. / Open Journal of Obstetrics and Gynecology 2 (2012) 304-310

306

gold standard type. When regional anaesthesia, epidural

or spinal are not available, an adequate pudendal block

and inhalation anaesthetic or general anesthesia remain

the option. Ten milliliters of a local anesth etic (lidocaine,

chloroprocaine, bupivacaine) should be injected below

the ischial spines bilaterally and at least ten more to the

laceration area. Enough care should be taken to make

sure that the rectal sphincter is anesthetized prior to the

repair.

It is essential that the full extent of the laceration is

discerned, including extension of the laceration and

“button holes” defecting into the rectal mucosa. A careful

rectal examination should be performed with the use of

index finger by elevating the anterior rectal wall into the

vagina. The rectal glove should be changed before con-

tinuing with the repair. It is often useful to place a pad

(usually a long pack of gauze pad) high into the vagina to

prevent blood from the uterus of obscuring the view.

Sometimes the anatomy is not clear and it becomes more

apparent as the wound is being repaired. If the tear is

complex, a more experienced operator may be required.

In order to decrease dead space and strengthen the

rectovaginal septum, three to four interrupted or running

00-polyglycolic acid sutures should be placed into the

internal anal sphincter and rectovaginal fascia. Of course

care should be taken to prevent entry into the rectal lu-

men [1,10].

Where the internal anal sphincter can be identified, it

is advisable to be repaired separately with interrupted

sutures. The size of suture must be such as 3-0 PDS and

2-0 Vicryl which may cause less irritation and discomfort

[11].

Regarding repair of the external anal sphincter there

are two surgical techniques, the overlapping and the end

to end (approximation) method. The ends of the sphinc-

ter must be clearly identified and grasped with Alis

clamps.

The end-to-end technique is used to bring the ends of

the sphincter together at each quadrant (12, 3, 6, and 9

o’clock) using interrupted sutures placed through the

capsule and muscle (Figure 2) [12,13].

Allis Clamps are placed on each end of the external

anal sphincter. Monofilament sutures such as polydiaxa-

none (PDS) or modern braided interrupted sutures such

as polyglactin (Vicryl) are placed at “posterior, inferior,

superior and anterior” side of sphincter. Recent evidence

suggests that end-to-end repairs have poorer anatomic

and functional outcomes than was previously believed

[1,14].

An alternative technique is overlapping repair of the

external anal sphincter. It brings together the ends of the

sphincter with mattress sutures (Figure 2) and results in

a larger surface area of tissue contact between the two

torn ends. Dissection of the external anal sphincter from

(a)

(b)

Figure 2. Over lap (a) and end to end technique (b).

the surrounding tissue with Metzenbaum scissors may be

required to achieve adequate length for the overlapping

of the muscles. The suture is passed from top to bottom

through the superior and inferior flaps, then from bottom

to top through the inferior and superior flaps. The proxi-

mal end of the superior flap overlies the distal portion of

the inferior flap. Two more sutures are placed in the

same manner. After all three sutures are placed, they are

each tied snugly, but without strangulation. When tied,

the knots are on the top of the overlapped sphincter ends.

Care must be taken to incorporate the muscle capsule in

the closure [15- 17].

A recent randomized controlled study of one hundred

and twenty-eight patients with grade three tears, included

119 (end-to-end 60, overlap 59) which received the allo-

cated treatment. The obtained information concerning

fecal incontinence from 101 (85%) patients shows that

one patient in the end-to-end group and none in the

overlap group reported leakage of solid stool once a

week or more. Fourteen patients in the end-to-end group

and 10 in the overlap group reported flatus incontinence

(p = 0.48). Defect of external sphincter was found in

2/46 in the end-to-end group compared to 0/41 in the

overlap group (NS). There was no difference in anal

manometry findings in both groups. Compendiously

A. Daniilidis et al. / Open Journal of Obstetrics and Gynecology 2 (2012) 304-310 307

there was no significant advantage between overlap re-

pair and approximation technique with regard to fecal

incontinence at 1 year [18].

Current RCOG (Royal College of Obstetricians and

Gynecologists) classification of obstetrics perineal trauma

pintpoints that the anatomic structures together with the

physiological functions of tissue involved in ano-rectal

continence should always be respected [11]. Experience

of the surgeon, operating theatre and its equipment,

asepsis, lighting, operating instruments, anesthesia, ma-

terial and type of suture as well as medication, are related

with the effectiveness of the repair. A delay up to 8 - 12

hours in primary repair does not seem to be detrimental

to the functional outcome of the procedure [19].

1.3. Complications of Third Degree Tears and

Treatment Methods

Several studies give an estimation of 15% of complica-

tions of third degree laceration repairs. The most com-

mon complications are: wound dehiscence, hematoma,

rectovaginal fistula, rectocutaneus fistula, perineal ab-

scess, anal incontinence, dyspareunia. The most common

et i ol o gies for these k inds of complications are summar i ze d

in Table 3. These complications occur in patients with

insulin-dependent diabetes, cancer, or an immunosup-

pressive disorder. Multiple bacterial pathogens are re-

sponsible for necrotizing fasciitis and the wound should

be recognized of the cyanotic discoloration and the loss

of sensation. This situations should be usually managed

with surgical debridement and allowance of broad spec-

trum antibiotics [1,16,20]. In a retrospective study of 27

women with 140 days follow up the feasibility of an

overlapping anal sphincter repair instead of end to end

repair was evaluated [21]. The study includes women

who delivered vaginally between June 1995-November

1996 complicated by a third degree perineal tear (Table

4). The internal sph incter was repaired separately and the

torn ends of the external sphincter were overlapped and

sutured with 3/0 PDS sutures (Ethicon, Edinburgh, UK).

Table 3. Etiology of complications.

 Infection

 Hematoma

 Poor tissue approximation (poor surgical technique)

 Obesity

 Poor perineal hygiene

 Malnutrition

 Anemia

 Constipation

 Blunt or penetrating tra uma

 Forceful coitus

 Cigarette smoking

 Inflammatory bo wel disease

 Connective tissue disease

 Prior pelvic radiation

 Hematologic disease

 Endometriosis

Table 4. Bowel symptoms, anal manometry and endosonogra-

phy in women with overlap sphincter repair (n = 27). Values are

given as n (%) [21].

Symptoms Percent

Incontinence of flatus 8%

Anal endosonography

External sphincter 15%

Internal sphincter 44%

Bowel symptoms

Faecal ur gency 15%

The conclusion of this study was that there are reserva-

tions regarding the feasibility of the overlap versus end

to end repair technique. Another retrospective cohort

study included 626 primiparous women with three and

six months follow up, after vaginal delivery [22]. 209 of

them received an episiotomy, 206 did not but experi-

enced a second, third, or fourth degree spontaneous per-

ineal laceration and 211 had no laceration or a first de-

gree perineal laceration. This study concluded that mid-

line episiotomy is not effective in protecting the per-

ineum and sphincters during childbirth and may impair

anal continence (Table 5). A new study [23] was per-

formed to evaluate the prevalence of anal incontinence

(AI) in primiparous women five years after their first

delivery. It included 242 primiparous women in order to

evaluate the prevalence of anal incontinence (AI) in five

years after their first delivery. Women with sphincter tear

(n = 36) at their first delivery were compared to women

without such injury (n = 206). Anal incontinence in-

creased significantly after the 5-year follow-up. Among

women with sphincter tears, 44% reported anal inconti-

nence at nine months and 53% at five years (p = 0.002).

Risk factors for anal incontinence at five years were age

(OR 2.2, 95% CI 1.0; 4.6), sphincter tear (OR 2.3, 1.1;

5.0) and subsequent childbirth (OR 2.4, 1.1; 5.6) (Table

6). In this cohort study thirty-six (15%) of the women

had a sphincter tear. After 9 months, 68/242 women

(28%) reported anal incontinence symptoms and after 5

years 85/242 women (35%) reported symptoms of anal

incontinence (p < 0.0001) (Ta b l e 7 , Figure 3). Another

systematic review on the method of repair of third-de-

gree tears [24] included three trials of 279 women. This

review reported that there was no significant difference

in perineal pain (RR0.08, 95% CI 0.00 - 1.45), dyspare-

unia (RR 0.62, 95% CI 0.11 - 3.39), flatus incontinence

(RR 0.93, 95% CI 0.2 - 3.31) and faecal incontinence

(RR 0.07, 95% CI 0.00 - 1.21), between the two repair

techniques at 1 year, but there was a significantly lower

incidence in faecal urgency (RR 0.12, 95% CI 0.02 -

0.86). Some studies report anal incontinence symptoms

A. Daniilidis et al. / Open Journal of Obstetrics and Gynecology 2 (2012) 304-310

308

OPEN ACCESS

Table 5. Risk of anal incontinence three and six months after childbirth for varying degrees of perineal injury. Figures are numbers

(percentage) of women [22].

Outcome Intact/1st degree tear

(intact grou p) 2nd

degree tea r3rd/4th

degree tea r2nd/3rd/4th degree

tear (tear group)Episiotomy

(episiotomy g roup) Episiotom y with

no extension

Faecal incontinence

At 3 months 5/205 (2.4) 5/154 (3.3) 2/50 (4.0) 7/204 (3.4) 20/203 (9.9) 13/147 (8.8)

At 6 months 3/201 (1.5) 3/152 (2.0) 0/49 (0) 3/201 (1.5) 8/195 (4.1) 6/141 (4.3)

Flatus incontinence:

At 3 months 40/192 (20.8) 27/144 (18.8)9/48 (18.8) 36/192 (18.8) 63/187 (33.7) 39/137 (28.5)

At 6 months 20/188 (10.6) 18/142 (12.7)5/47 (10.6) 23/189 (12.2) 42/181 (23.2) 26/133 (19.6)

Table 6. Type of delivery and sphincter tear [23].

Number and type of delivery No sphincter tear (n = 206) Sphincter tear (n = 36)

No subsequent childbirth 44 9

One subsequent vaginal delivery 134 20

Two subsequent vaginal deliveries 20 3

Three subsequent vaginal deliveries 1 0

One subsequent c-section 8* 1

Two subsequent c-sections 0 3

*One woman had both a c - section and a v aginal deli very.

Table 7. Degree of fecal incontinence and involuntary flatus [23].

Symptoms Sphincter tear No sphincter tear

9 mo after delivery 5 yrs after delivery 9 mo after delivery 5 yrs after delivery

No incontinence 56% (20/36) 47% (17/36) 75% (154/206) 68% (140/206)

Fecal incontinence

<1/week 0 11% (4/36)** 1% (3/206)* 4% (9/206)***

>1/week 0 0 0 0.5% (1/206)****

Daily 0 0 0 0

Involuntary flatus

<1/week 33% (12/ 3 6 ) 25% (9/36) 16% (33/206) 22% (45/206)

>1/week 11% (4/36) 22% (8/36) 7% (14/206) 7% (15/206)

Daily 0 6% (2/36) 1% (3/206) 2% (5/206)

*One woman also had incontinence to flatus; **All women were also incontinent to flatus; ***All but one woman were also incontinent to flatus; ****The women

also were incontinent to flatus.

in 20% - 67% of women with primary third-degree tear

repair. The type of incontinence is mainly flatus (up to

59%) with leakage of liquid and solid stool in up to 11%,

while faecal urgency occurred in 26% of these women.

In one study, there were symptoms of anal incontinence

after four years of follow-up (17% - 42%) [11,25]. These

studies used different questionnaires to assess anal incon-

tinence symptoms and it is not easy to compare studies’

outcomes [11]. Several randomised controlled studies

since 2000 comparing overlap and end-to-end techniques

of EAS repair, report low incidences of anal incontinence

symptoms in both sides, describing as asymptomatic

60% - 80% of women at 1 year 11. A randomized con-

trolled trial study investigates the association between

endoanal ultrasonography and anorectal manometry in

relation to anal incontinence after primary repair of ob

A. Daniilidis et al. / Open Journal of Obstetrics and Gynecology 2 (2012) 304-310 309

Figure 3. Anal incontinence at 9 months and 5 years in relation to subsequent childbirth [26]. Sphincter refers to

tear or no tear at the index delivery.

stetric sphincter injury in primiparous, premenopausal

women. It included 108 women who had previously been

part of a delayed primary repair of obstetric sphincter

injuries, and 12 months after the repair, they had been

evaluated by anorectal manometry and endoanal ultra-

sound. Impaired rectal sensation at anorectal manometry

and a scar at endoanal ultrasonography are associated

with anal incontinence 12 months after primary sphincter

repair in primiparous women [26].

Studies using endoanal ultrasound as follow-up show

persistent defects in 54% - 88% of women after primary

repair of third-degree tears. More recently, randomised

controlled trials have reported fewer residual defects

(about 19% - 36% overall). The clinical relevance of

asymptomatic defects demonstrated by ultrasound is cur-

rently unclear [11,26].

2. CONCLUSION

Although episiotomy is an important risk factor for se-

vere lacerations after vaginal delivery, there are other

significant independent risk factors, such as maternal age,

birth weight, and assisted vaginal delivery, which should

be considered in counseling and making decisions re-

garding delivery modality. Older patients who deliver

their first child are at higher risk for severe laceration.

Midline episiotomy and assisted vaginal delivery should

be avoided in this population whenever possible, espe-

cially in the presence of a large baby. Recent evidence

suggests that no significant advantage between overlap

repair and approximation technique exists with regard to

fecal incontinence.

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