An interventional study of Negative Pressure Wound Therapy and Standard wound care in Pilonidal Sinus and Wound Healing, sponsored by Royal College of Surgeons, Ireland. Recruiting at 10 sites in Ireland. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-24.
Sponsored by Royal College of Surgeons, Ireland · Not applicable, Interventional, and Treatment
This is a single-blinded, multicentre, prospective randomised controlled trial (RCT) comparing post-operative and patient-reported outcomes for patients undergoing application of negative-pressure wound therapy (NPWT) after sinus tract excision as compared to excision and standard open wound care in chronic pilonidal sinus disease (PSD).
Pilonidal sinus disease (PSD) is a chronic inflammatory condition of the skin and subcutaneous tissues arising from hair follicles in the natal cleft. The definitive aetiology of the condition is unknown, however, it is theorised that it is the result of either the obstruction and subsequent inflammation of hair follicles or secondary to hair penetrating through the skin into the subcutaneous tissue. This results in infection, abscess formation, chronic discharge and pain. PSD is a common condition affecting 26 per 10,000 population, with the prevalence reaching 1.1% in young adult males.
PSD causes a significant burden on healthcare services due to high rates of recurrence and readmission following surgery, together with negative impacts on patients' quality of life and self-image. An effective management strategy for the disease is necessary to ensure that post-operative outcomes are optimised and patient-reported outcomes are satisfactory in those whose PSD requires surgery.
The objective of this multicentre, national RCT is to prospectively investigate the effect of negative pressure wound therapy compared to leaving open with standard wound care on time to wound healing following surgical excision of chronic PSD.
109 studies on the registry are indexed under Pilonidal Sinus; 32 are open to participants now.
This study's planned enrollment of 200 is above the median of 80 across 72 interventional studies indexed under Pilonidal Sinus.
Browse Pilonidal Sinus studies →Royal College of Surgeons, Ireland is the lead sponsor of 93 studies on the registry; 44 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
i) They are aged 18 years or older
ii) They are undergoing elective pilonidal sinus excision without primary closure
Exclusion Criteria:
i) They are unable to adhere to protocol requirements e.g. questionnaire completion
ii) They are undergoing emergency drainage for a pilonidal abscess
iii) They are undergoing surgery for pilonidal sinus disease in locations other than the natal cleft
iv) They have underlying osteomyelitis
v) They have underlying fistulating disease e.g. Crohn's
The wound is dressed using negative pressure wound therapy.
Device: Negative Pressure Wound Therapy
Following excision, the wound is left open (no primary closure) and managed with standard dressings according to local protocol, with wound healing by secondary intention.
Other: Standard wound care
Following elective excision of chronic pilonidal sinus disease with the wound left open, NPWT is applied in theatre using a polyurethane foam-based system (e.g. VAC, Renasys-GO, Prevena or equivalent) cut to fit the wound cavity, sealed with an adhesive drape and connected to a portable pump at -125 mmHg continuous pressure. Dressings are changed every 48-72 hours in clinic until granulation reaches skin level, followed by standard dressings until epithelialisation.
Standard wound care
Time to complete wound healing
Number of days to complete epithelialisation or closure of the wound without any discharge, drainage, scab, and/or the requirement for further dressing.
Time frame: Up to 6 months post surgery
Measure of post operative pain
Pain measured by visual analogue pain scale (0 = no pain, 10 = worst pain) at rest, on walking and on sitting
Time frame: Day of surgery, 28 days post surgery & 3 months post surgery
Measure of post operative complications
Post-operative complications, including surgical site infection (CDC criteria), seroma, abscess, readmission and return to theatre.
Time frame: 6 months post surgery
To compare recurrence rates
To compare the 6-month recurrence rates (recurrence being defined as the development of a new sinus or abscess within the natal cleft occurring after wound healing had been achieved) between the NPWT and SWC Groups
Time frame: 6 months post surgery
Cost-effectiveness
Within-trial cost-utility analysis from health-system and patient perspectives, expressed as incremental cost per QALY gained (QALYs from EQ-5D-5L, area under the curve). Resource use includes hospital and community contacts, dressing changes, complications, readmissions and returns to theatre, valued at Irish unit costs; patient costs and productivity losses via CoPaQ.
Time frame: 6 months post surgery
Health-related quality of life with the EuroQol-5 dimensions five level index questionnaire (EQ-5D-5L)
The questionnaire covers five dimensions of health: mobility, self-care, usual activities, pain or discomfort, and anxiety or depression. Each dimension has 5 levels: no problems (1), slight problems (2), moderate problems (3), severe problems (4) and extreme problems (5). The patient is asked to indicate his/her health state by ticking the box next to the most appropriate statement in each of the five dimensions. Index values derived using the EQ-5D-5L value set specified in the Statistical Analysis Plan (Irish value set where available).
Time frame: Baseline, 1 month, 3 months & 6 months
Scar assessment - using the Patient and Observer Scar Assessment Scale (POSAS)
The POSAS is made up of two scales: the patient and observer scales each comprise six items scored 1 to 10; each scale is summed (6 = normal, 60 = worst) and reported separately.
Time frame: 28 days, 3 months, 6 months
Health-related out-of- Pocket Costs assessed using the Costs for Patients Questionnaire (CoPaQ)
The CoPaQ measures patient and caregivers out-of-pocket expenses (direct and indirect) associated with a health condition
Time frame: 28 days, 3 months, 6 months
Plan to share: No
No publications or documents are linked to this record.
Started Oct 2024 (actual). Primary completion is estimated for Dec 2026, 26 months after the start.
Of 35 interventional studies with no phase under Pilonidal Sinus, half reached primary completion within 24 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 35. This study's planned 26 months is close to that.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Royal College of Surgeons, Ireland