Pilonidal sinus treatment: A new simplified technique; filling natal cleft with fasciofatty flap.

Pilonidal sinus treatment: A new simplified technique; filling natal cleft with fasciofatty flap.

Mokhtar Abd Elrahman A Bahbah,MD; Ehab  M Oraby,MD

Department of General Surgery, Benha University, Benha, Egypt.

Abstract

Background:  Karydakis and Bascom designed new lines of surgical treatment of pilonidal sinus. Both of them share the principles of off-midline scar and cleft lift. The objective of this randomized clinical trial was to evaluate prospectively the outcome of adding few modifications to both techniques ofKarydakis and Bascom.

Method: Sixty eight patients with pilonidal sinus were included in this study. After eradication

of pathological tissues; the skin flap was created, afasciofatty flap was everted to fill the natal cleft. On table removal of drain was done after sutureless collapse ofwound cavity.

Results: The depth of the natal cleft showed a clear reduction. Four cases (5.9%) developed

seroma which required simple needle aspiration. All patients attended the follow up period with no recurrences.

Conclusion: This technique carries the simplicity with promising results. It helps in pathology eradication and reduction of natal cleft depth through a reliable filling with fasciofatty flap.

Key words: Pilonidal sinus, Karydakis-modification, Bascom modification, fascia-fatty flap, cleft lift, sutureless collapse of wound cavity.

Introduction:

Pilonidal sinus is a chronic subcutaneous abscess in the natal cleft, which spontaneously drains through its openings. The first documented   case   of   pilonidal   sinus   was done by  A.W. Anderson in his letter to the editor that appeared in an issue of the Boston Medical Surgical Journal of 1847, entitled "Hair  Extracted from an Ulcer,".1

In  1880,  Hodges  coined  the  term "pilonidal sinus" (pilus, meaning hair, and nidus, meaning nest) to describe the chronic sinus  containing   hair  and  found   between the buttocks. He believed the condition  was congenital in origin, representing an imperfect union ofthe lateral halves ofthe body.2

Buie  called  it  "jeep  disease" because

of the frequent complaint among military personnel under stresses of driving trucks, tanks, and jeeps.3

During  World  War  II  seventy-nine thousand U.S. servicemen were hospitalized, each for an average 55 days, because of pilonidal disease and its treatment. 4

Etiology and pathogenesis

The origin of the pilonidal sinus has been a subject of interest for many years. The congenital theory was popular. 5 Even in the modem  era,  the  congenital  theory  still  has its  proponents.  Lord reasoned  that  hairs  in the pilonidal sinuses are identical in length, diameter, color, and orientation. He said, "It is hard to conceive any other theories that explain  how  hair can get  into the pilonidal sinus from outside, which could possibly explain  how  23  hairs  should  follow  each other into a pilonidal sinus and each hair be identical in every respect to the last. "6

The  acquired  theory  is now  widely accepted.    Its    mechanism,     however,    1s

speculative and varied. Bascom believes the affected hair follicles become distended with keratin and subsequently  infected, leading to folliculitis  and the formation  of an abscess that extends down into the subcutaneous fat. Once the abscess cavity is formed, hairs can enter through the tiny pit and lodge in the abscess cavity from the suction created by movement ofthe gluteal area.7

Karydakis,  on  the  other  hand,  believes the shaft of loose hair, because of its scales with  chisel-like  root  ends,  inserts  into  the depth of the natal cleft in the midline of sacrococcygeal area. Friction forces and skin vulnerability help this step of hair insertion. Once  one  hair  inserts   successfully,   other hairs can insert more easily. Foreign body tissue reaction and infection follow, and the primary sinus of pilonidal disease forms. Secondary  openings  often occur  because of the self-propelling ability of hair to burrow through the skin, or spontaneous  rupture of the  abscess.  The  secondary  openings  have a  different   appearance   from   the   primary midline ones in that they are marked by elevations of granulation tissue and discharge of seropurulent  material.  Hairs, if seen, sticking out of the secondary opening are in the abscess cavity that the body tries to spit out.8

Unusual locations of pilonidal sinus, such as the umbilicus, a healed amputation stump, and  interdigital   clefts,  and  the  recurrence of the disease in an adequately excised area support the acquired theory of this disease particularly    Karydakis 's   concept   of   hair insertion.

Most sinus tracts (93%) run cephalad; the

rest  (7%) run caudad  and may be confused with a fistula-in-ano  or with hidradenitis suppurativa.9

Treatment   of   pilonidal    sinus   can   be done in one of several ways: non operative treatment,  lateral  incision  and  excision  of midline  pits, incision  and  marsupialization, wide local excision with or without  primary closure, excision and Z-plasty, or advancing flap operation (Karydakis procedure). Karydakis procedure:

Karydakis designed an operative technique

to abolish risk factors. A "semi  lateral" excision is made over the sinuses all the way down to the presacral fascia. Mobilization is carried to the opposite side so that the entire thick flap can be advanced toward the other side on closure. A closed suction drain is placed. This technique avoids the midline wound.lO

Ina series of7471 patients who received the advancing  flap  procedure,  the complication rate was 8.5%, mainly infection and fluid collection. The mean hospital stay was three days, with many patients requiring one day hospitalization  or  the  procedure  performed on  an outpatient  basis.  The  recurrence  rate was 1%, with follow up ranging from 2 to 20 years. In each recurrence, reinsertion of hairs was observed. The Karydakis flap procedure has proved to be effective,8,11,12 but it is a moderately extensive procedure.

Bascom's flap (cleft lift):

This unique method for treating the unhealed  wound  was devised  by Bascom.13

The basic concept  is to excise the unhealed skin and the underlying subcutaneous tissue. The natal cleft is eliminated by replacing the defect at the depth of the cleft with a skin flap over the wound. This operation is easier than it  appears  and  is  less extensive  than  other types of flaps. The subcutaneous fat is not mobilized.  The flap  is a full thickness  skin flap. The procedure is performed with the patient  under  general  or  spinal  anesthesia. A broad-spectrum  antibiotic  is administered when  the  patient  is  called  to the  operating room and continued until the drain is removed four to five days later. The patient is placed in the prone jack knife position. With the patient's buttocks  pressed together, the lines of contact of the cheeks of the buttocks are marked with a felt-tipped pen. The cheeks of the buttocks are then taped apart, and the skin is prepared and draped.

The skin in this region is infiltrated with

0.25%   bupivacaine   (Marcaine)   containing

1:200,000  epinephrine to decrease bleeding. A triangle-shaped section  of skin  overlying the  unhealed  wound  is  excised,  extending above and lateral to the apex ofthe cleft. The lower end of the incision  is curved medially

toward the anus to avoid a "dog-ear" upon closure. The granulation tissue and hairs are removed. No fat or muscle is mobilized. After the skin flap (dissected only into the dermis) is raised out to the previously marked line on the left side, he scrubbed out abscess cavities with gauze. He slices scar and abscess walls to release tense contractures but leaves scar fragments  in place, attached to fat, to ensure blood supply.l4

Then  the  tapes   are  released.  The  skin flap is positioned to overlap the edges of the wound on the right side. The excess skin is excised. A closed suction drain is placed in the subcutaneous tissue. The subcutaneous tissue is closed  with 3-0  chromic  catgut,  and  the skin is closed with subcuticular 3-0 synthetic monofilament absorbable suture. The suture line can be reinforced with a running suture, or Steristrips can be applied.

The key to this operation  is to create the skin flap so that the suture line is off the midline.   It should  be  noted  that  Bascom described this technique to treat unhealed wound  or  recurrent  pilonidal  sinuses, although it is possible to use it for a complex primary disease.

Patients and methods:

Sixty eight  consecutive  patients  with chronic natal cleft pilonidal sinuses seen over a period of 15 months (January 2012 to March

2013)   were   included   in  this   prospective study. The ages of the patients ranged from

16 to 38 with a mean age of24.4 years. There were 44 males and 24 females with a male I female  ratio of 1.8:1.   Sixty patients had de novo sinuses with no previous attempt of surgical treatment, and 8 patients (11.8%) had recurrent sinuses following previous surgical treatment with excision and primary midline closure.  All  recurrences  occurred  within  2 years after the first surgery.

Surgical technique:

In this study, operations in 24 cases were done under spinal anesthesia and the other 10 cases under general anesthesia. With induction of anesthesia;  I.V. dose of  Augmentine  1.2 gm vial was given. Patient was positioned in prone jack knife position.  The pelvic girdle

was supported and raised with a soft pillow. While pressing both buttocks against each other; a marking pen was used to delineate the line of contact between both buttocks from above the natal cleft, down to a level opposite anal verge. Then both buttocks were tapped apart  to  expose  the  natal  cleft.   Povidone iodine 10% was used as skin antiseptic.

In this study we preferred to inject adrenaline    1/200,000    into    subcutaneous plane  to  facilitate   bloodless  dissection   of sinus tracts. Also, we preferred not to use methylene blue injection into sinus tracts.

The  previous  marking  lines  were considered the guide for incision and the limiting border for operative dissection. The incision was carried down on the line on left side. Incision was about 5-7cm in length "usually  upper point 2cm above the level of upper sinus pit passing downward to a point

1cm  below the  level of lower  sinus  pit". It

was advisable not to go beyond the coccygeal tip. A curved incision starting from the upper point to the  lower point passing  0.5-1cm to the right side of the pilonidal sinus pits was made.

The  inclSlon  was  deepened   about  1cm into the subcutaneous fat then started to go medially to dissect directly around the fibrotic tract. In the circumstances of bloodless field; a clear view of the whitish fibrotic tract was obtained.

The  aim  of  dissection  here  was to minimize  excision of healthy nearby tissues to a minimal degree. In all cases we did not reach  the  presacral  fascia.   The  dissection was limited around fibrous tract of pilonidal sinus. This dissection was carried out by coagulating diathermy.

In branched pilonidal sinus or laterally placed external opening, the incision was modified by adding extension limb or V-cut in the direction of this sinus opening or branch.

After  completing  the  elliptical  excision of pilonidal sinus tract; we started to create an advancement  flap  from  the  right  border of the wound. Undermining  of skin flap was done creating a flap thickness 0.7-1cm "skin and subcutaneous  fat".  The  limiting  border of dissection was the marking line. Opposite

this limiting border, a deep cut was done through gluteal fat to reach and divide the fascia covering the gluteus maximus muscle. Then  we  started  to  dissect  the  fascia  back from  its  muscle  towards  the  midline  to  a degree that allowed a tension free eversion of this fascio-fatty flap. Suturing ofthe everted fascia to the fibro-fatty tissues of the left side was done. This last step allowed filling ofthe natal cleft "cleft  lift" and also exposed area of muscle surface and subfascial plain with a rich lymphatic drainage "internal  drainage".

Hemostasis was checked for any bleeding points  and  dealt  with  by  coagulation diathermy. Subcutaneous tube drain was inserted in the wound bed through a different stab away from midline. A purse string suture was placesd around the point of drain exit and held withouttie. The plaster tape was released then  the  wound  was  closed  in two  layers. First layer was inverted deep dermal stitches using  Vicryl 3-0  sutures.  The second  layer was interrupted vertical mattress suture by Prolene 3-0 sutures. The suture line was sited over previous left marking line. The new cleft became obviously shallow cleft. The wound was totally placed in exposed area away from deep moist cleft.

After complete  closure  of skin; the tube

drain was connected to suction machine to induce  sutureless  collapse  of  cavity.  Then, a firm  dressing  was applied  over  operative area with on table removal of drain and simultaneously tightening the purse string suture.

All patients  were  allowed  for  overnight stay and were discharged after 24 hours. Postoperative  pain control  was achieved  by oral Paracetamol and NSAID.

Patients were scheduled for postoperative follow  up visits  at  outpatient  clinic  on  5th and 12th days. Stitches were removed on 12th postoperative  day. Further  follow  up visits are scheduled after 3 and 6 months later.

Results:

The  main  complaint  of  all  the  patients was mild pain and discomfort in the sacral region, with a chronically  discharging  sinus or  sinuses.  A  single  sinus  was  present  in

34 patients, multiple midline sinuses were present in 26 patients, and lateral sinuses in 8 patients. In the 8 cases with lateral sinuses, all were recurrent cases and the eighth case with lateral sinus was type I DM.   The operative time  ranged from  40 to 80 minutes,  with  a mean operative time of 56.5±3.3 minutes.

All  cases  were  admitted  for  24  hours and discharged  safely  without  delay  in the

1st   postoperative   day.  No   cases   required

readmission for any reason.

Only  4 patients (5.9%)  developed wound seroma  detected  on the  5th day at the  first wound inspection, which required simple aspiration through wide bore needle.

Postoperative     pain     control    with     oral

Paracetamol  and  NSAIDs  was  satisfactory and sufficient for all patients. All patients with recurrent diseases reported less postoperative pain compared to the previous surgery.

All    cases    attended    outpatient    clinic on  the   12th  postoperative   day   with   nice wound healing and stitches were removed successfully.   All   patients   attended   the   3 months and 6 months follow up period with no recurrences.

In one case known as type I DM; the pilonidal  sinus  tract  was  Y-shaped.  Right limb ended with skin sinus while left limb ended  as  blind  track  in  the  subcutaneous tissue. The common stem contained multiple midline  sinuses.  The  incision  in  this  case was  modified  by  adding  a  V- cut  incision to involve the right limb while the  left limb was easily excised after extension of incision towards the right side. This case experienced post-operative wound seroma which required simple needle aspiration every other day for

4 times.

Discussion:

In 1992, Dr. George Karydakis published the largest personal series in the world.l o He excised the sinus with a simple biconvex elliptical   incision,   only   just  crossing   the midline to excise the sinus down to the sacrum. A thick flap of skin and subcutaneous tissue was then created. This flap was advanced across the midline to meet the other side of the wound with two layers of catgut sutures

f

Figure (1): Drawing natal cleft border.

Drawing done by my clinic Filipino nurse: Gian C. Victoria.

Figure (3): Incision line "blue line",  done toward left side.

Figure (5): After excision of pilonidal sinus track.

Figure (7): Exposure of gluteus maximus muscle.

Figure (2): Limiting border of natal cleft.

Figure (4): Incision line done toward right side due to right sided pilonidal sinus opening.

Figure (6): Creatingfasciofatty flap.

Figure (8): Eversion and fixation of fasciofatty flap "filling of natal cleft".

Figure (9): Excised specimen skin view and undersurface view showing fibrous tract contain blackish content "hair".

Figure (11): On table drain removal. Off midline wound, toward right side.

Figure (13): Branched pilonidal sinus with lateral opening.

Figure (15): Excised Y-shaped sinus tract.

Figure (10): Drain insertion and wound closure. Notice purse string suture around drain exit.

Figure (12): Off midline wound toward left side.

Figure (14): Modified incision for branched pilonidal sinus.

Figure (16): Modified incision after skin closure.

Figure (17): 6 months post operative follow up; complete healing and no recurrence.

Table shows comparative points between the three different techniques for operative treatment of pilonidal  sinus.

to the  fat.  The wound  was then  closed  with skin sutures  with suction  drainage.l4,15 Using this technique he reported a recurrence rate of less than  1%. He attributed those  recurrences to hair reinsertion.!o The same  results of Karydakis  were reproduced by others, with a hospital stay ranging from 4 to 16 days.l6-19

In spite of his good results,  Karydakis has described the following difficulties during his procedure:

1- Difficulty in fixing  the flap  was found  to be due to stitch cutting out of the loose fat on the side ofthe flap.l0,16

2-   The   complication  rate   has    remained high (8.5%). These were mainly due to infection  and fluid collection.l0,16

3-  It was  observed  that   as  young   people developed   adult   body  form,   there   was a change in the skin of the mid-line, following   Karydakis     operation.    The skin   in  the   depth   of  the  "new"  natal cleft developed  the characteristics of a vulnerable raphe,  with wide pores and maceration.l0,16

Bascom's technique is a day case surgery, which  can  be  done  under  local  anesthesia, which similarly places the main wound  away from   the  midline.   He  reported   an  average time  of healing  of 4 weeks  and a recurrence rate   of  8%.17,7,20  Another   modification reported also  by Bascom  is the  cleft closure technique.l 7,21,22   A   thinner   subcutaneous flap  is used  to shift the scar  off the  midline. Bascom technique is to scrub out abscess cavities with gauze. He slices scar and abscess walls to release tense  contractures but leaves scar  fragments in  place,  attached  to  fat,  to ensure blood supply.22

The procedure  is simpler  than the original Karydakis  technique, and may be done under local   anesthesia  as  a  day   case   procedure but  with  a high  incidence of  wound  failure and only in 33% of cases the wound healed primarily.17

In  our   study;  the  planned   incision   line puts  the  final  skin  wound   over  the  top  of gluteal  region  away  from  moist  natal  cleft. This  offered   a  good   dry   environment for wound healing without wound maceration, anaerobic infection  and finally  wound failure

and disruption.

The  created  flap  (7-10  mm)  was  not  as thick as Karydakis flap and this gave the flap more  strechability. On  the  other  hand;  also it was not very thin  as Bascom  flap  and this made  the  flap  stronger  and  of more  reliable blood supply.

Dissection was limited  to around the wall of the fibrous track of pilonidal sinus. This limited dissection made less tissue  loss and resulted   in less wound  cavity and subsequent less seroma  formation.

The   creation   of  fasciofatty  flap   opens the subfascial plane  with  its high  lymphatic drainage,   this   is  suspected  to   abolish   the need for wound drainage with decreased incidence of seroma  complication and wound disruption.

The  created fasciofatty flap  also gives mechanical filling  of the natal  cleft with subsequent obvious  reduction in natal cleft depth.

Eversion  of fasciofatty flap  allows the stitches  to be taken  in the fascia  rather  than the   fat.   The   fascia   holds   stitches    better and  therefore holds  the  flap  better  and  this leads to reliable filling of natal cleft. This technique takes a middle  pathway  between Karydakis   and  Bascom   flap  techniques. It carries  advantage of  Karydakis technique in complete   excision  of  pathological tissues. Also,  it  is  equal  to  Bascom   technique  in the simplicity of flap  dissection and  limited tissue  excision  with preservation of non­ pathological tissues.  But I think that this new technique provides a further step in advantage of  simplicity,   pathology  eradication,  natal cleft  lift and minimal  tissue  excision.  In this technique; the  external  drainage  is replaced by internal  drainage  through muscle  surface and subfascial plane.

A longer  period  of follow-up is needed  to confirm  the  previously mentioned  benefits; the new technique is still a simple  one which is suitable  for  de-novo  as well  as  recurrent and complex cases after  addition  of suitable modification of skin incision.

It is also suitable for day case surgery since no drainage  is needed  and the pain was easily controlled with oral non-steroidal drugs.