Pilonidal sinus
Meaning of pilonidal sinus: For the purposes of this Statement of Principles, pilonidal sinus: (a) means an inflammatory tissue reaction of the skin to an embedded hair which is manifested by the development of a sinus or fistula; and (b) includes pilonidal cyst and pilonidal fistula; and (c) excludes ingrown hair.
Reasonable Hypothesis (RH) — Statement of Principles No. 27 of 2019
At least one of the following factors must as a minimum exist before it can be said that a reasonable hypothesis has been raised connecting pilonidal sinus or death from pilonidal sinus with the circumstances of a person's relevant service:
- (1)for pilonidal sinus of the hand or foot only: (a) working as a hairdresser or barber within the six months before the clinical onset of pilonidal sinus; or (b) having cutaneous exposure to animal hair within the six months before the clinical onset of pilonidal sinus;
Note: having cutaneous exposure to animal hair is defined in the Schedule 1 - Dictionary.
- (2)for pilonidal sinus of the sacrococcygeal region only: (a) driving or being a seated passenger in a motorised vehicle for an average of at least 20 hours per week for a period of at least three months, within the six months before the clinical onset of pilonidal sinus; or (aa) sitting on a hard or vibrating surface for an average of at least 20 hours per week for a period of at least three months, within the six months before the clinical onset of pilonidal sinus; or Compilation No. 1 Compilation date: 20/12/2021 Authorised Version F2021C01296 registered 20/12/2021 (b) being overweight or obese within the six months before the clinical onset of pilonidal sinus;
Note: being overweight or obese is defined in the Schedule 1 - Dictionary.
- (3)for pilonidal sinus of the sacrococcygeal and umbilical regions only, inability to shower or bathe more than two times per week for a period of at least four weeks, within the six months before the clinical onset of pilonidal sinus;
- (4)for pilonidal sinus of the hand or foot only: (a) working as a hairdresser or barber within the six months before the clinical worsening of pilonidal sinus; or (b) having cutaneous exposure to animal hair within the six months before the clinical worsening of pilonidal sinus;
Note: having cutaneous exposure to animal hair is defined in the Schedule 1 - Dictionary.
- (5)for pilonidal sinus of the sacrococcygeal region only: (a) driving or being a seated passenger in a motorised vehicle for an average of at least 20 hours per week for a period of at least three months, within the six months before the clinical worsening of pilonidal sinus; or (aa) sitting on a hard or vibrating surface for an average of at least 20 hours per week for a period of at least three months, within the six months before the clinical worsening of pilonidal sinus; or (b) being overweight or obese within the six months before the clinical worsening of pilonidal sinus;
Note: being overweight or obese is defined in the Schedule 1 - Dictionary.
- (6)for pilonidal sinus of the sacrococcygeal and umbilical regions only, inability to shower or bathe more than two times per week for a period of at least four weeks, within the six months before the clinical worsening of pilonidal sinus;
- (7)inability to obtain appropriate clinical management for pilonidal sinus;
Aggravation-only factors: the factors in subsections 9(4) to 9(7) apply only to material contribution to, or aggravation of, the condition where it was suffered or contracted before or during (but did not arise out of) the person’s relevant service.
Balance of Probabilities (BoP) — Statement of Principles No. 28 of 2019
7 factors
At least one of the following factors must exist before it can be said that, on the balance of probabilities, pilonidal sinus or death from pilonidal sinus is connected with the circumstances of a person's relevant service:
- (1)for pilonidal sinus of the hand or foot only: (a) working as a hairdresser or barber within the six months before the clinical onset of pilonidal sinus; or (b) having cutaneous exposure to animal hair within the six months before the clinical onset of pilonidal sinus;
Note: having cutaneous exposure to animal hair is defined in the Schedule 1 - Dictionary.
- (2)for pilonidal sinus of the sacrococcygeal region only: (a) driving or being a seated passenger in a motorised vehicle for an average of at least 20 hours per week for a period of at least three months, within the six months before the clinical onset of pilonidal sinus; or (b) being overweight or obese within the six months before the clinical onset of pilonidal sinus;
Note: being overweight or obese is defined in the Schedule 1 - Dictionary.
- (3)for pilonidal sinus of the sacrococcygeal and umbilical regions only, inability to shower or bathe more than two times per week for a period of at least four weeks, within the six months before the clinical onset of pilonidal sinus;
- (4)for pilonidal sinus of the hand or foot only: (a) working as a hairdresser or barber within the six months before the clinical worsening of pilonidal sinus; or (b) having cutaneous exposure to animal hair within the six months before the clinical worsening of pilonidal sinus;
Note: having cutaneous exposure to animal hair is defined in the Schedule 1 - Dictionary.
- (5)for pilonidal sinus of the sacrococcygeal region only: (a) driving or being a seated passenger in a motorised vehicle for an average of at least 20 hours per week for a period of at least three months, within the six months before the clinical worsening of pilonidal sinus; or (b) being overweight or obese within the six months before the clinical worsening of pilonidal sinus;
Note: being overweight or obese is defined in the Schedule 1 - Dictionary.
- (6)for pilonidal sinus of the sacrococcygeal and umbilical regions only, inability to shower or bathe more than two times per week for a period of at least four weeks, within the six months before the clinical worsening of pilonidal sinus;
- (7)inability to obtain appropriate clinical management for pilonidal sinus;
Aggravation-only factors: the factors in subsections 9(4) to 9(7) apply only to material contribution to, or aggravation of, the condition where it was suffered or contracted before or during (but did not arise out of) the person’s relevant service.








