EP774 - Gluteal Fold Antisymmetrization with Cleft Flattening and Off-Midline Limberg Flap, Without architectural concordance, For Recurrent lateral Pilonidal Disease– Retrospective Study.

Purpose/Background: Recurrent lateral pilonidal disease (RLPD) is a concern with best reported results of 'off-midline' Limberg flaps (LF). Coccygo-cutaneous fascial disconnection with unlocking of gluteal fold symmetry, achieved by Gluteal Fold antisymmetrization with Cleft Flattening added to 'Off-Midline Limberg Flap' (GACO), can address the concern. We report our experience with GACO.

Methods/Interventions: From 2012 Jan to 2024 July, 91 RLPD cases underwent GACO without using surgical energy, with standard protocols for informed consent, daycare/ ambulatory surgery (Hospital Stay < 1 Day), anaesthesia, per-operative antibiotic prophylaxis, perioperative medication & ABCDEF discharge (A-Activity, B-Bath, C-Commitment, D-Diet, F-Family Life, resumption within 72 hrs.). Data (minimum 1 year follow-up) was retrieved from the Hospital Information System for the following end point-

1. Any technical difficulty in tension free closure (TFC)

2. Unusual drainage

3. Flap Ischaemia

4. Recurrence

Technique- Marking of 10 &20 openings was done in buttocks apart prone position in General/ Regional anaesthesia (Fig 1/1). Craniocaudal extent of RLPD (marked x) in midline marked (Fig 1/2_8cms indicative here). Similar transverse line centred at 1st line (Fig 1/3). Horizontal line drawn laterally till beyond the level of lateral most opening (from the caudal end of midline-2cms indicative & at least 1.5cms indicative from the cranial end (Fig 1/4). Ends of the vertical & transverse line joined to mark the Rhombus-indicative each arm length (AL) being 5.5-6cms (Fig 1/5). The LF was marked with AL=AL of the Rhombus (Fig 1/6). Cranial & caudal horizontal lines were joined to the left lateral angle of the Rhombus (Fig 1/7). The boundary of the marked area for excision was infiltrated (30-40 ml of 0.2 ml adrenaline in 100 ml saline). The marked area was excised irrespective of shape/size concordance with the shape of LF (Fig 1/8). Coccyx-Skin fascial density was divided by knife to be mobile & freely lift the natal cleft skin on finger. The medial point of the caudal horizontal line was sutured to lower 2 cms of the left inferolateral excision margin (Fig 1/9). The LF with gluteal fascia was raised, rotated/ transpositioned & sutured (interrupted 2-0 Vicryl) over a closed suction drain, to fill the cavity by approximating recipient & donor margins by 'divide the wound in halves' wound closure principle (Fig 1/10).

The patients were followed on Day3/5, Day 7, Day10, Day 15/16, & monthly for a year, for flap integrity or drain removal, suture removal & recurrence respectively.

Results/Outcomes: No difficulty in TFC. The Flap could cover > 1.5x area excised. All discharges as 'daycare surgery'. No post-operative bleeding or abnormal drainage. All resumed ABCDEF within 72 hrs. One patient each had superficial gangrene at the apex of the flap & 'segmental margin dehiscence' delaying healing by 3 weeks. Rest of results are shown in Figure 2.

Conclusion/Discussion: The 'Gluteal Fold Antisymmetrization with Cleft Flattening and Off-Midline Limberg Flap' is feasible as daycare procedure with outcomes better than the reported outcomes of 'off-midline Limberg flap'. It reduces recurrence further by achieving -

1. Flattening of the natal cleft & abolishing potential intertrigo.

2. Removing the friction + suction + electrostatic trap for hair, by abolishing the symmetry and kissing of the gluteal folds, achieved by elevation & contralateral positioning of one gluteal lip of the natal cleft.

A longer follow-up & prospective multi-centric studies will help in studying the robustness of technique.

Figure 1
Fig 2